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I work with Tsimane hunter-horticulturalists in Bolivia and San hunter-gatherers in Namibia. I have recently started training in health sciences and neuroscience to complement my training in anthropological sleep science.<br /><span class="u-fw700">Supervisors: </span>Jerome Siegel<br /><div class="js-profile-less-about u-linkUnstyled u-tcGrayDarker u-textDecorationUnderline u-displayNone">less</div></div></div><div class="suggested-academics-container"><div class="suggested-academics--header"><h3 class="ds2-5-heading-sans-serif-xs">Related Authors</h3></div><ul class="suggested-user-card-list" data-nosnippet="true"><div class="suggested-user-card"><div class="suggested-user-card__avatar social-profile-avatar-container"><a data-nosnippet="" href="https://utoronto.academia.edu/DavidSamson"><img class="profile-avatar u-positionAbsolute" alt="David Samson related author profile picture" border="0" onerror="if (this.src != '//a.academia-assets.com/images/s200_no_pic.png') this.src = '//a.academia-assets.com/images/s200_no_pic.png';" width="200" height="200" 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id="social-redesign-work-container"><div class="upload-header"><h2 class="ds2-5-heading-sans-serif-xs">Uploads</h2></div><div class="documents-container backbone-social-profile-documents" style="width: 100%;"><div class="u-taCenter"></div><div class="profile--tab_content_container js-tab-pane tab-pane active" id="all"><div class="profile--tab_heading_container js-section-heading" data-section="Papers" id="Papers"><h3 class="profile--tab_heading_container">Papers by Gandhi Yetish</h3></div><div class="js-work-strip profile--work_container" data-work-id="30242563"><div class="profile--work_thumbnail hidden-xs"><a class="js-work-strip-work-link" data-click-track="profile-work-strip-thumbnail" href="https://www.academia.edu/30242563/What_is_segmented_sleep_Actigraphy_field_validation_for_daytime_sleep_and_nighttime_wake"><img alt="Research paper thumbnail of What is segmented sleep? Actigraphy field validation for daytime sleep and nighttime wake" class="work-thumbnail" src="https://a.academia-assets.com/images/blank-paper.jpg" /></a></div><div class="wp-workCard wp-workCard_itemContainer"><div class="wp-workCard_item wp-workCard--title"><a class="js-work-strip-work-link text-gray-darker" data-click-track="profile-work-strip-title" href="https://www.academia.edu/30242563/What_is_segmented_sleep_Actigraphy_field_validation_for_daytime_sleep_and_nighttime_wake">What is segmented sleep? Actigraphy field validation for daytime sleep and nighttime wake</a></div><div class="wp-workCard_item wp-workCard--coauthors"><span>by </span><span><a class="" data-click-track="profile-work-strip-authors" href="https://utoronto.academia.edu/DavidSamson">David Samson</a> and <a class="" data-click-track="profile-work-strip-authors" href="https://ucla.academia.edu/GandhiYetish">Gandhi Yetish</a></span></div><div class="wp-workCard_item"><span class="js-work-more-abstract-truncated">Objective: To compare different scoring parameter settings in actigraphy software for inferring s...</span><a class="js-work-more-abstract" data-broccoli-component="work_strip.more_abstract" data-click-track="profile-work-strip-more-abstract" href="javascript:;"><span> more </span><span><i class="fa fa-caret-down"></i></span></a><span class="js-work-more-abstract-untruncated hidden">Objective: To compare different scoring parameter settings in actigraphy software for inferring sleep and<br />wake bouts for validating analytical techniques outside of laboratory environments.<br />Design: To identify parameter settings that best identify napping during periods of wakefulness, we<br />analyzed 137 days on which participants reported daytime napping, as compared with a random subset<br />of 30 days when no naps were reported. To identify settings that identify periods of wakefulness during<br />sleep,we used data from a subsample of women who reported discrete wake bouts while nursing at night.<br />Setting: Equatorial Tanzania in January to February 2016.<br />Participants: The Hadza—a non-industrial foraging population.<br />Measurements: Thirty-three subjects participated in the study for 393 observation days. Using the Bland-<br />Altman technique to determine concordance, we analyzed reported events of daytime napping and nighttime<br />wake bouts.<br />Results: Only 1 parameter setting could reliably detect reported naps (15-minute nap length, ≤50 counts).<br />Moreover, of the 6 tested parameter settings to detect wake bouts, the setting where the sleep-wake<br />algorithm was parameterized to detect 20 consecutive minutes throughout the designated sleep period<br />did not overestimate or underestimate wake bouts, had the lowest mean difference, and did not<br />significantly differ from reported wake-bout events.<br />Conclusion: We propose operational definitions for multiple dimensions of segmented sleep and conclude<br />that actigraphy is an effective method for detecting segmented sleep in future cross-site comparative<br />research. The implications of such work are far reaching, as sleep research in preindustrial and developing<br />societies is documenting natural sleep-wake patterns in previously inaccessible environments.</span></div><div class="wp-workCard_item wp-workCard--actions"><span class="work-strip-bookmark-button-container"></span><a id="df41c0aa4012caf96ca8582a9c511f31" class="wp-workCard--action" rel="nofollow" data-click-track="profile-work-strip-download" data-download="{"attachment_id":50707569,"asset_id":30242563,"asset_type":"Work","button_location":"profile"}" href="https://www.academia.edu/attachments/50707569/download_file?s=profile"><span><i class="fa fa-arrow-down"></i></span><span>Download</span></a><span class="wp-workCard--action visible-if-viewed-by-owner inline-block" style="display: none;"><span class="js-profile-work-strip-edit-button-wrapper profile-work-strip-edit-button-wrapper" data-work-id="30242563"><a class="js-profile-work-strip-edit-button" tabindex="0"><span><i class="fa fa-pencil"></i></span><span>Edit</span></a></span></span></div><div class="wp-workCard_item wp-workCard--stats"><span><span><span class="js-view-count view-count u-mr2x" data-work-id="30242563"><i class="fa fa-spinner fa-spin"></i></span><script>$(function () { var workId = 30242563; window.Academia.workViewCountsFetcher.queue(workId, function (count) { var description = window.$h.commaizeInt(count) + " " + window.$h.pluralize(count, 'View'); $(".js-view-count[data-work-id=30242563]").text(description); $(".js-view-count[data-work-id=30242563]").attr('title', description).tooltip(); }); });</script></span></span><span><span class="percentile-widget hidden"><span class="u-mr2x work-percentile"></span></span><script>$(function () { var workId = 30242563; window.Academia.workPercentilesFetcher.queue(workId, function (percentileText) { var container = $(".js-work-strip[data-work-id='30242563']"); container.find('.work-percentile').text(percentileText.charAt(0).toUpperCase() + percentileText.slice(1)); container.find('.percentile-widget').show(); container.find('.percentile-widget').removeClass('hidden'); }); });</script></span></div><div id="work-strip-premium-row-container"></div></div></div><script> require.config({ waitSeconds: 90 })(["https://a.academia-assets.com/assets/wow_profile-a9bf3a2bc8c89fa2a77156577594264ee8a0f214d74241bc0fcd3f69f8d107ac.js","https://a.academia-assets.com/assets/work_edit-ad038b8c047c1a8d4fa01b402d530ff93c45fee2137a149a4a5398bc8ad67560.js"], function() { // from javascript_helper.rb var dispatcherData = {} if (true){ window.WowProfile.dispatcher = window.WowProfile.dispatcher || _.clone(Backbone.Events); dispatcherData = { dispatcher: window.WowProfile.dispatcher, downloadLinkId: "df41c0aa4012caf96ca8582a9c511f31" } } $('.js-work-strip[data-work-id=30242563]').each(function() { if (!$(this).data('initialized')) { new WowProfile.WorkStripView({ el: this, workJSON: {"id":30242563,"title":"What is segmented sleep? Actigraphy field validation for daytime sleep and nighttime wake","translated_title":"","metadata":{"abstract":"Objective: To compare different scoring parameter settings in actigraphy software for inferring sleep and\nwake bouts for validating analytical techniques outside of laboratory environments.\nDesign: To identify parameter settings that best identify napping during periods of wakefulness, we\nanalyzed 137 days on which participants reported daytime napping, as compared with a random subset\nof 30 days when no naps were reported. To identify settings that identify periods of wakefulness during\nsleep,we used data from a subsample of women who reported discrete wake bouts while nursing at night.\nSetting: Equatorial Tanzania in January to February 2016.\nParticipants: The Hadza—a non-industrial foraging population.\nMeasurements: Thirty-three subjects participated in the study for 393 observation days. Using the Bland-\nAltman technique to determine concordance, we analyzed reported events of daytime napping and nighttime\nwake bouts.\nResults: Only 1 parameter setting could reliably detect reported naps (15-minute nap length, ≤50 counts).\nMoreover, of the 6 tested parameter settings to detect wake bouts, the setting where the sleep-wake\nalgorithm was parameterized to detect 20 consecutive minutes throughout the designated sleep period\ndid not overestimate or underestimate wake bouts, had the lowest mean difference, and did not\nsignificantly differ from reported wake-bout events.\nConclusion: We propose operational definitions for multiple dimensions of segmented sleep and conclude\nthat actigraphy is an effective method for detecting segmented sleep in future cross-site comparative\nresearch. The implications of such work are far reaching, as sleep research in preindustrial and developing\nsocieties is documenting natural sleep-wake patterns in previously inaccessible environments.\n"},"translated_abstract":"Objective: To compare different scoring parameter settings in actigraphy software for inferring sleep and\nwake bouts for validating analytical techniques outside of laboratory environments.\nDesign: To identify parameter settings that best identify napping during periods of wakefulness, we\nanalyzed 137 days on which participants reported daytime napping, as compared with a random subset\nof 30 days when no naps were reported. To identify settings that identify periods of wakefulness during\nsleep,we used data from a subsample of women who reported discrete wake bouts while nursing at night.\nSetting: Equatorial Tanzania in January to February 2016.\nParticipants: The Hadza—a non-industrial foraging population.\nMeasurements: Thirty-three subjects participated in the study for 393 observation days. Using the Bland-\nAltman technique to determine concordance, we analyzed reported events of daytime napping and nighttime\nwake bouts.\nResults: Only 1 parameter setting could reliably detect reported naps (15-minute nap length, ≤50 counts).\nMoreover, of the 6 tested parameter settings to detect wake bouts, the setting where the sleep-wake\nalgorithm was parameterized to detect 20 consecutive minutes throughout the designated sleep period\ndid not overestimate or underestimate wake bouts, had the lowest mean difference, and did not\nsignificantly differ from reported wake-bout events.\nConclusion: We propose operational definitions for multiple dimensions of segmented sleep and conclude\nthat actigraphy is an effective method for detecting segmented sleep in future cross-site comparative\nresearch. The implications of such work are far reaching, as sleep research in preindustrial and developing\nsocieties is documenting natural sleep-wake patterns in previously inaccessible environments.\n","internal_url":"https://www.academia.edu/30242563/What_is_segmented_sleep_Actigraphy_field_validation_for_daytime_sleep_and_nighttime_wake","translated_internal_url":"","created_at":"2016-12-04T08:01:02.434-08:00","preview_url":null,"current_user_can_edit":null,"current_user_is_owner":null,"owner_id":671632,"coauthors_can_edit":true,"document_type":"paper","co_author_tags":[{"id":26371539,"work_id":30242563,"tagging_user_id":671632,"tagged_user_id":5641726,"co_author_invite_id":null,"email":"g***i@yetish.com","affiliation":"University of California, Los Angeles","display_order":1,"name":"Gandhi Yetish","title":"What is segmented sleep? 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To identify settings that identify periods of wakefulness during\nsleep,we used data from a subsample of women who reported discrete wake bouts while nursing at night.\nSetting: Equatorial Tanzania in January to February 2016.\nParticipants: The Hadza—a non-industrial foraging population.\nMeasurements: Thirty-three subjects participated in the study for 393 observation days. Using the Bland-\nAltman technique to determine concordance, we analyzed reported events of daytime napping and nighttime\nwake bouts.\nResults: Only 1 parameter setting could reliably detect reported naps (15-minute nap length, ≤50 counts).\nMoreover, of the 6 tested parameter settings to detect wake bouts, the setting where the sleep-wake\nalgorithm was parameterized to detect 20 consecutive minutes throughout the designated sleep period\ndid not overestimate or underestimate wake bouts, had the lowest mean difference, and did not\nsignificantly differ from reported wake-bout events.\nConclusion: We propose operational definitions for multiple dimensions of segmented sleep and conclude\nthat actigraphy is an effective method for detecting segmented sleep in future cross-site comparative\nresearch. The implications of such work are far reaching, as sleep research in preindustrial and developing\nsocieties is documenting natural sleep-wake patterns in previously inaccessible environments.\n","owner":{"id":671632,"first_name":"David","middle_initials":null,"last_name":"Samson","page_name":"DavidSamson","domain_name":"utoronto","created_at":"2011-08-17T03:13:26.908-07:00","display_name":"David Samson","url":"https://utoronto.academia.edu/DavidSamson"},"attachments":[{"id":50707569,"title":"","file_type":"pdf","scribd_thumbnail_url":"https://a.academia-assets.com/images/blank-paper.jpg","file_name":"Samson_et_al._2016_What_is_segmented_sleep_Actigraphy_field_validation_for_daytime_sleep_and_nighttime_wake.pdf","download_url":"https://www.academia.edu/attachments/50707569/download_file","bulk_download_file_name":"What_is_segmented_sleep_Actigraphy_field.pdf","bulk_download_url":"https://d1wqtxts1xzle7.cloudfront.net/50707569/Samson_et_al._2016_What_is_segmented_sleep_Actigraphy_field_validation_for_daytime_sleep_and_nighttime_wake-libre.pdf?1480867378=\u0026response-content-disposition=attachment%3B+filename%3DWhat_is_segmented_sleep_Actigraphy_field.pdf\u0026Expires=1743222881\u0026Signature=VIfvFiCUqFP~k~Cbmarw6GDHcHtTYIGfbBhAWinZifGfga~e7Ni1Fqadz5O4tdSqg6tB1E1vlT0AnMYqx9kPmI32uNk8QlwxBXME6mo4HPLujVapNxVssYR9UM69b2xth~T~-tw1iad3aYkXYWCLBf0Ziuvlt-0Xq57b4fr5KXrh5-zDin-TShC8I2ihWAmBvAxg74J7Kuje3qUrSj1neyHFMDpX~q4UkBMmxiHgY1mvq8UACC5dYMzXVrlk7GnBAsICd8khukuoo62EwpoQy2X6kX5G3xcDHbVcnaVSFnzOxy1J26zb20jXQVDgSyfA4qB1w3W5lSOPTrEseQmwKQ__\u0026Key-Pair-Id=APKAJLOHF5GGSLRBV4ZA"}],"research_interests":[{"id":32948,"name":"Hunter-Gatherers (Anthropology)","url":"https://www.academia.edu/Documents/in/Hunter-Gatherers_Anthropology_"},{"id":61109,"name":"Validation","url":"https://www.academia.edu/Documents/in/Validation"},{"id":133324,"name":"Sleep","url":"https://www.academia.edu/Documents/in/Sleep"},{"id":276765,"name":"Actigraphy","url":"https://www.academia.edu/Documents/in/Actigraphy"},{"id":330336,"name":"Research in the field of IT Engineering/ Electronics Engineering","url":"https://www.academia.edu/Documents/in/Research_in_the_field_of_IT_Engineering_Electronics_Engineering"}],"urls":[]}, dispatcherData: dispatcherData }); $(this).data('initialized', true); } }); $a.trackClickSource(".js-work-strip-work-link", "profile_work_strip") if (false) { Aedu.setUpFigureCarousel('profile-work-30242563-figures'); } }); </script> <div class="js-work-strip profile--work_container" data-work-id="16943541"><div class="profile--work_thumbnail hidden-xs"><a class="js-work-strip-work-link" data-click-track="profile-work-strip-thumbnail" href="https://www.academia.edu/16943541/Patterns_of_senescence_in_human_cardiovascular_fitness_VO_2_max_in_subsistence_and_industrialized_populations"><img alt="Research paper thumbnail of Patterns of senescence in human cardiovascular fitness: VO 2 max in subsistence and industrialized populations" class="work-thumbnail" src="https://attachments.academia-assets.com/39269714/thumbnails/1.jpg" /></a></div><div class="wp-workCard wp-workCard_itemContainer"><div class="wp-workCard_item wp-workCard--title"><a class="js-work-strip-work-link text-gray-darker" data-click-track="profile-work-strip-title" href="https://www.academia.edu/16943541/Patterns_of_senescence_in_human_cardiovascular_fitness_VO_2_max_in_subsistence_and_industrialized_populations">Patterns of senescence in human cardiovascular fitness: VO 2 max in subsistence and industrialized populations</a></div><div class="wp-workCard_item"><span>American Journal of Human Biology</span><span>, 2013</span></div><div class="wp-workCard_item"><span class="js-work-more-abstract-truncated">Objectives: This study explores whether cardiovascular fitness levels and senescent decline are s...</span><a class="js-work-more-abstract" data-broccoli-component="work_strip.more_abstract" data-click-track="profile-work-strip-more-abstract" href="javascript:;"><span> more </span><span><i class="fa fa-caret-down"></i></span></a><span class="js-work-more-abstract-untruncated hidden">Objectives: This study explores whether cardiovascular fitness levels and senescent decline are similar in the Tsimane of Bolivia and Canadians, as well as other subsistence and industrialized populations. Among Tsimane, we examine whether morbidity predicts lower levels and faster decline of cardiovascular fitness, or whether their lifestyle (e.g., high physical activity) promotes high levels and slow decline. Alternatively, high activity levels and morbidity might counterbalance such that Tsimane fitness levels and decline are similar to those in industrialized populations.</span></div><div class="wp-workCard_item wp-workCard--actions"><span class="work-strip-bookmark-button-container"></span><a id="e43c40f562e2c45da7e46a51bfa70e62" class="wp-workCard--action" rel="nofollow" data-click-track="profile-work-strip-download" data-download="{"attachment_id":39269714,"asset_id":16943541,"asset_type":"Work","button_location":"profile"}" href="https://www.academia.edu/attachments/39269714/download_file?s=profile"><span><i class="fa fa-arrow-down"></i></span><span>Download</span></a><span class="wp-workCard--action visible-if-viewed-by-owner inline-block" style="display: none;"><span class="js-profile-work-strip-edit-button-wrapper profile-work-strip-edit-button-wrapper" data-work-id="16943541"><a class="js-profile-work-strip-edit-button" tabindex="0"><span><i class="fa fa-pencil"></i></span><span>Edit</span></a></span></span></div><div class="wp-workCard_item wp-workCard--stats"><span><span><span class="js-view-count view-count u-mr2x" data-work-id="16943541"><i class="fa fa-spinner fa-spin"></i></span><script>$(function () { var workId = 16943541; window.Academia.workViewCountsFetcher.queue(workId, function (count) { var description = window.$h.commaizeInt(count) + " " + window.$h.pluralize(count, 'View'); $(".js-view-count[data-work-id=16943541]").text(description); $(".js-view-count[data-work-id=16943541]").attr('title', description).tooltip(); }); });</script></span></span><span><span class="percentile-widget hidden"><span class="u-mr2x work-percentile"></span></span><script>$(function () { var workId = 16943541; window.Academia.workPercentilesFetcher.queue(workId, function (percentileText) { var container = $(".js-work-strip[data-work-id='16943541']"); container.find('.work-percentile').text(percentileText.charAt(0).toUpperCase() + percentileText.slice(1)); container.find('.percentile-widget').show(); container.find('.percentile-widget').removeClass('hidden'); }); });</script></span></div><div id="work-strip-premium-row-container"></div></div></div><script> require.config({ waitSeconds: 90 })(["https://a.academia-assets.com/assets/wow_profile-a9bf3a2bc8c89fa2a77156577594264ee8a0f214d74241bc0fcd3f69f8d107ac.js","https://a.academia-assets.com/assets/work_edit-ad038b8c047c1a8d4fa01b402d530ff93c45fee2137a149a4a5398bc8ad67560.js"], function() { // from javascript_helper.rb var dispatcherData = {} if (true){ window.WowProfile.dispatcher = window.WowProfile.dispatcher || _.clone(Backbone.Events); dispatcherData = { dispatcher: window.WowProfile.dispatcher, downloadLinkId: "e43c40f562e2c45da7e46a51bfa70e62" } } $('.js-work-strip[data-work-id=16943541]').each(function() { if (!$(this).data('initialized')) { new WowProfile.WorkStripView({ el: this, workJSON: {"id":16943541,"title":"Patterns of senescence in human cardiovascular fitness: VO 2 max in subsistence and industrialized populations","translated_title":"","metadata":{"ai_title_tag":"Cardiovascular Fitness in Aging Populations","grobid_abstract":"Objectives: This study explores whether cardiovascular fitness levels and senescent decline are similar in the Tsimane of Bolivia and Canadians, as well as other subsistence and industrialized populations. Among Tsimane, we examine whether morbidity predicts lower levels and faster decline of cardiovascular fitness, or whether their lifestyle (e.g., high physical activity) promotes high levels and slow decline. Alternatively, high activity levels and morbidity might counterbalance such that Tsimane fitness levels and decline are similar to those in industrialized populations.","publication_date":{"day":null,"month":null,"year":2013,"errors":{}},"publication_name":"American Journal of Human Biology","grobid_abstract_attachment_id":39269714},"translated_abstract":null,"internal_url":"https://www.academia.edu/16943541/Patterns_of_senescence_in_human_cardiovascular_fitness_VO_2_max_in_subsistence_and_industrialized_populations","translated_internal_url":"","created_at":"2015-10-18T05:22:42.942-07:00","preview_url":null,"current_user_can_edit":null,"current_user_is_owner":null,"owner_id":5641726,"coauthors_can_edit":true,"document_type":"paper","co_author_tags":[],"downloadable_attachments":[{"id":39269714,"title":"","file_type":"pdf","scribd_thumbnail_url":"https://attachments.academia-assets.com/39269714/thumbnails/1.jpg","file_name":"00b7d52332edb5e718000000.pdf","download_url":"https://www.academia.edu/attachments/39269714/download_file","bulk_download_file_name":"Patterns_of_senescence_in_human_cardiova.pdf","bulk_download_url":"https://d1wqtxts1xzle7.cloudfront.net/39269714/00b7d52332edb5e718000000-libre.pdf?1445170985=\u0026response-content-disposition=attachment%3B+filename%3DPatterns_of_senescence_in_human_cardiova.pdf\u0026Expires=1743222881\u0026Signature=Py7TGrKy37CZZPPVWOTcoOwutVMfGf6i8Fhlc~mQSC3BLYha6mMeqEhCs~tVjoaLJc-S2bz77OIOX45vKdv7ji-9EEkxe6faFSAronPLlMxhcXRddtQVpN9WX1~ky7w58L-ZT8MgrN2nrGnbPfa8YcXsesRMSXdncrMQOC-gozsKNuWXKBaSVQoyMzdLZ491oz-sKbSbFB2QNSsFM07lH5rvZDWA-Dcun5b8GcgR7Rm6w8qJMzI91BZWusJH~uA~Jg3CmqjxS9BS4E0fsfC3iQBoOmOJV6qHLEEpshBcQD7sCXhL9UcScQ~qqgNPl-2la6LvDnq~NS1-6Ez7H4uvug__\u0026Key-Pair-Id=APKAJLOHF5GGSLRBV4ZA"}],"slug":"Patterns_of_senescence_in_human_cardiovascular_fitness_VO_2_max_in_subsistence_and_industrialized_populations","translated_slug":"","page_count":14,"language":"en","content_type":"Work","summary":"Objectives: This study explores whether cardiovascular fitness levels and senescent decline are similar in the Tsimane of Bolivia and Canadians, as well as other subsistence and industrialized populations. Among Tsimane, we examine whether morbidity predicts lower levels and faster decline of cardiovascular fitness, or whether their lifestyle (e.g., high physical activity) promotes high levels and slow decline. Alternatively, high activity levels and morbidity might counterbalance such that Tsimane fitness levels and decline are similar to those in industrialized populations.","owner":{"id":5641726,"first_name":"Gandhi","middle_initials":null,"last_name":"Yetish","page_name":"GandhiYetish","domain_name":"ucla","created_at":"2013-09-19T08:22:04.517-07:00","display_name":"Gandhi Yetish","url":"https://ucla.academia.edu/GandhiYetish"},"attachments":[{"id":39269714,"title":"","file_type":"pdf","scribd_thumbnail_url":"https://attachments.academia-assets.com/39269714/thumbnails/1.jpg","file_name":"00b7d52332edb5e718000000.pdf","download_url":"https://www.academia.edu/attachments/39269714/download_file","bulk_download_file_name":"Patterns_of_senescence_in_human_cardiova.pdf","bulk_download_url":"https://d1wqtxts1xzle7.cloudfront.net/39269714/00b7d52332edb5e718000000-libre.pdf?1445170985=\u0026response-content-disposition=attachment%3B+filename%3DPatterns_of_senescence_in_human_cardiova.pdf\u0026Expires=1743222881\u0026Signature=Py7TGrKy37CZZPPVWOTcoOwutVMfGf6i8Fhlc~mQSC3BLYha6mMeqEhCs~tVjoaLJc-S2bz77OIOX45vKdv7ji-9EEkxe6faFSAronPLlMxhcXRddtQVpN9WX1~ky7w58L-ZT8MgrN2nrGnbPfa8YcXsesRMSXdncrMQOC-gozsKNuWXKBaSVQoyMzdLZ491oz-sKbSbFB2QNSsFM07lH5rvZDWA-Dcun5b8GcgR7Rm6w8qJMzI91BZWusJH~uA~Jg3CmqjxS9BS4E0fsfC3iQBoOmOJV6qHLEEpshBcQD7sCXhL9UcScQ~qqgNPl-2la6LvDnq~NS1-6Ez7H4uvug__\u0026Key-Pair-Id=APKAJLOHF5GGSLRBV4ZA"}],"research_interests":[{"id":155,"name":"Evolutionary Biology","url":"https://www.academia.edu/Documents/in/Evolutionary_Biology"},{"id":591,"name":"Nutrition and Dietetics","url":"https://www.academia.edu/Documents/in/Nutrition_and_Dietetics"},{"id":767,"name":"Anthropology","url":"https://www.academia.edu/Documents/in/Anthropology"},{"id":6791,"name":"Aging","url":"https://www.academia.edu/Documents/in/Aging"},{"id":7471,"name":"Life Style","url":"https://www.academia.edu/Documents/in/Life_Style"},{"id":9815,"name":"Developing Countries","url":"https://www.academia.edu/Documents/in/Developing_Countries"},{"id":11552,"name":"Bolivia","url":"https://www.academia.edu/Documents/in/Bolivia"},{"id":22506,"name":"Adolescent","url":"https://www.academia.edu/Documents/in/Adolescent"},{"id":54114,"name":"Canada","url":"https://www.academia.edu/Documents/in/Canada"},{"id":91707,"name":"American Journal of Human Biology","url":"https://www.academia.edu/Documents/in/American_Journal_of_Human_Biology"},{"id":131298,"name":"Heart rate","url":"https://www.academia.edu/Documents/in/Heart_rate"},{"id":133057,"name":"Young Adult","url":"https://www.academia.edu/Documents/in/Young_Adult"},{"id":268784,"name":"Physical Fitness","url":"https://www.academia.edu/Documents/in/Physical_Fitness"},{"id":289271,"name":"Aged","url":"https://www.academia.edu/Documents/in/Aged"},{"id":311522,"name":"Developed Countries","url":"https://www.academia.edu/Documents/in/Developed_Countries"},{"id":559242,"name":"Cardiovascular Diseases","url":"https://www.academia.edu/Documents/in/Cardiovascular_Diseases"},{"id":1034181,"name":"Cross Sectional Studies","url":"https://www.academia.edu/Documents/in/Cross_Sectional_Studies"},{"id":1146831,"name":"Exercise Test","url":"https://www.academia.edu/Documents/in/Exercise_Test"},{"id":1193624,"name":"Oxygen Consumption","url":"https://www.academia.edu/Documents/in/Oxygen_Consumption"}],"urls":[]}, dispatcherData: dispatcherData }); $(this).data('initialized', true); } }); $a.trackClickSource(".js-work-strip-work-link", "profile_work_strip") if (false) { Aedu.setUpFigureCarousel('profile-work-16943541-figures'); } }); </script> <div class="js-work-strip profile--work_container" data-work-id="16877852"><div class="profile--work_thumbnail hidden-xs"><a class="js-work-strip-work-link" data-click-track="profile-work-strip-thumbnail" href="https://www.academia.edu/16877852/Natural_sleep_and_its_seasonal_variants_in_three_pre_industrial_societies"><img alt="Research paper thumbnail of Natural sleep and its seasonal variants in three pre-industrial societies" class="work-thumbnail" src="https://attachments.academia-assets.com/39233258/thumbnails/1.jpg" /></a></div><div class="wp-workCard wp-workCard_itemContainer"><div class="wp-workCard_item wp-workCard--title"><a class="js-work-strip-work-link text-gray-darker" data-click-track="profile-work-strip-title" href="https://www.academia.edu/16877852/Natural_sleep_and_its_seasonal_variants_in_three_pre_industrial_societies">Natural sleep and its seasonal variants in three pre-industrial societies</a></div><div class="wp-workCard_item wp-workCard--coauthors"><span>by </span><span><a class="" data-click-track="profile-work-strip-authors" href="https://ucla.academia.edu/GandhiYetish">Gandhi Yetish</a>, <a class="" data-click-track="profile-work-strip-authors" href="https://independent.academia.edu/HillardKaplan">Hillard Kaplan</a>, <a class="" data-click-track="profile-work-strip-authors" href="https://independent.academia.edu/CharlesWilson26">Charles Wilson</a>, and <a class="" data-click-track="profile-work-strip-authors" href="https://independent.academia.edu/ronaldmcgregor">ronald mcgregor</a></span></div><div class="wp-workCard_item"><span class="js-work-more-abstract-truncated">How did humans sleep before the modern era? Because the tools to measure sleep under natural cond...</span><a class="js-work-more-abstract" data-broccoli-component="work_strip.more_abstract" data-click-track="profile-work-strip-more-abstract" href="javascript:;"><span> more </span><span><i class="fa fa-caret-down"></i></span></a><span class="js-work-more-abstract-untruncated hidden">How did humans sleep before the modern era?<br />Because the tools to measure sleep under natural<br />conditions were developed long after the invention<br />of the electric devices suspected of delaying and<br />reducing sleep, we investigated sleep in three preindustrial<br />societies [1–3]. We find that all three show<br />similar sleep organization, suggesting that they<br />express core human sleep patterns, most likely characteristic<br />of pre-modern era Homo sapiens. Sleep<br />periods, the times from onset to offset, averaged<br />6.9–8.5 hr, with sleep durations of 5.7–7.1 hr,<br />amounts near the low end of those industrial societies<br />[4–7]. There was a difference of nearly 1 hr between<br />summer and winter sleep. Daily variation in<br />sleep duration was strongly linked to time of onset,<br />rather than offset. None of these groups began sleep<br />near sunset, onset occurring, on average, 3.3 hr after<br />sunset. Awakening was usually before sunrise. The<br />sleep period consistently occurred during the nighttime<br />period of falling environmental temperature,<br />was not interrupted by extended periods of waking,<br />and terminated, with vasoconstriction, near the nadir<br />of daily ambient temperature. The daily cycle of temperature<br />change, largely eliminated from modern<br />sleep environments, may be a potent natural regulator<br />of sleep. Light exposure was maximal in the<br />morning and greatly decreased at noon, indicating<br />that all three groups seek shade at midday and that<br />light activation of the suprachiasmatic nucleus<br />is maximal in the morning. Napping occurred<br />on <7% of days in winter and <22% of days in summer.<br />Mimicking aspects of the natural environment<br />might be effective in treating certain modern sleep<br />disorders.</span></div><div class="wp-workCard_item wp-workCard--actions"><span class="work-strip-bookmark-button-container"></span><a id="fac6b4dbac3bd04ad0916b9081f4c952" class="wp-workCard--action" rel="nofollow" data-click-track="profile-work-strip-download" data-download="{"attachment_id":39233258,"asset_id":16877852,"asset_type":"Work","button_location":"profile"}" href="https://www.academia.edu/attachments/39233258/download_file?s=profile"><span><i class="fa fa-arrow-down"></i></span><span>Download</span></a><span class="wp-workCard--action visible-if-viewed-by-owner inline-block" style="display: none;"><span class="js-profile-work-strip-edit-button-wrapper profile-work-strip-edit-button-wrapper" data-work-id="16877852"><a class="js-profile-work-strip-edit-button" tabindex="0"><span><i class="fa fa-pencil"></i></span><span>Edit</span></a></span></span></div><div class="wp-workCard_item wp-workCard--stats"><span><span><span class="js-view-count view-count u-mr2x" data-work-id="16877852"><i class="fa fa-spinner fa-spin"></i></span><script>$(function () { var workId = 16877852; window.Academia.workViewCountsFetcher.queue(workId, function (count) { var description = window.$h.commaizeInt(count) + " " + window.$h.pluralize(count, 'View'); $(".js-view-count[data-work-id=16877852]").text(description); $(".js-view-count[data-work-id=16877852]").attr('title', description).tooltip(); }); });</script></span></span><span><span class="percentile-widget hidden"><span class="u-mr2x work-percentile"></span></span><script>$(function () { var workId = 16877852; window.Academia.workPercentilesFetcher.queue(workId, function (percentileText) { var container = $(".js-work-strip[data-work-id='16877852']"); container.find('.work-percentile').text(percentileText.charAt(0).toUpperCase() + percentileText.slice(1)); container.find('.percentile-widget').show(); container.find('.percentile-widget').removeClass('hidden'); }); });</script></span></div><div id="work-strip-premium-row-container"></div></div></div><script> require.config({ waitSeconds: 90 })(["https://a.academia-assets.com/assets/wow_profile-a9bf3a2bc8c89fa2a77156577594264ee8a0f214d74241bc0fcd3f69f8d107ac.js","https://a.academia-assets.com/assets/work_edit-ad038b8c047c1a8d4fa01b402d530ff93c45fee2137a149a4a5398bc8ad67560.js"], function() { // from javascript_helper.rb var dispatcherData = {} if (true){ window.WowProfile.dispatcher = window.WowProfile.dispatcher || _.clone(Backbone.Events); dispatcherData = { dispatcher: window.WowProfile.dispatcher, downloadLinkId: "fac6b4dbac3bd04ad0916b9081f4c952" } } $('.js-work-strip[data-work-id=16877852]').each(function() { if (!$(this).data('initialized')) { new WowProfile.WorkStripView({ el: this, workJSON: {"id":16877852,"title":"Natural sleep and its seasonal variants in three pre-industrial societies","translated_title":"","metadata":{"abstract":"How did humans sleep before the modern era?\nBecause the tools to measure sleep under natural\nconditions were developed long after the invention\nof the electric devices suspected of delaying and\nreducing sleep, we investigated sleep in three preindustrial\nsocieties [1–3]. We find that all three show\nsimilar sleep organization, suggesting that they\nexpress core human sleep patterns, most likely characteristic\nof pre-modern era Homo sapiens. Sleep\nperiods, the times from onset to offset, averaged\n6.9–8.5 hr, with sleep durations of 5.7–7.1 hr,\namounts near the low end of those industrial societies\n[4–7]. There was a difference of nearly 1 hr between\nsummer and winter sleep. Daily variation in\nsleep duration was strongly linked to time of onset,\nrather than offset. None of these groups began sleep\nnear sunset, onset occurring, on average, 3.3 hr after\nsunset. Awakening was usually before sunrise. The\nsleep period consistently occurred during the nighttime\nperiod of falling environmental temperature,\nwas not interrupted by extended periods of waking,\nand terminated, with vasoconstriction, near the nadir\nof daily ambient temperature. The daily cycle of temperature\nchange, largely eliminated from modern\nsleep environments, may be a potent natural regulator\nof sleep. Light exposure was maximal in the\nmorning and greatly decreased at noon, indicating\nthat all three groups seek shade at midday and that\nlight activation of the suprachiasmatic nucleus\nis maximal in the morning. Napping occurred\non \u003c7% of days in winter and \u003c22% of days in summer.\nMimicking aspects of the natural environment\nmight be effective in treating certain modern sleep\ndisorders.","ai_title_tag":"Seasonal Sleep Patterns in Pre-Industrial Societies"},"translated_abstract":"How did humans sleep before the modern era?\nBecause the tools to measure sleep under natural\nconditions were developed long after the invention\nof the electric devices suspected of delaying and\nreducing sleep, we investigated sleep in three preindustrial\nsocieties [1–3]. We find that all three show\nsimilar sleep organization, suggesting that they\nexpress core human sleep patterns, most likely characteristic\nof pre-modern era Homo sapiens. Sleep\nperiods, the times from onset to offset, averaged\n6.9–8.5 hr, with sleep durations of 5.7–7.1 hr,\namounts near the low end of those industrial societies\n[4–7]. There was a difference of nearly 1 hr between\nsummer and winter sleep. Daily variation in\nsleep duration was strongly linked to time of onset,\nrather than offset. None of these groups began sleep\nnear sunset, onset occurring, on average, 3.3 hr after\nsunset. Awakening was usually before sunrise. The\nsleep period consistently occurred during the nighttime\nperiod of falling environmental temperature,\nwas not interrupted by extended periods of waking,\nand terminated, with vasoconstriction, near the nadir\nof daily ambient temperature. The daily cycle of temperature\nchange, largely eliminated from modern\nsleep environments, may be a potent natural regulator\nof sleep. Light exposure was maximal in the\nmorning and greatly decreased at noon, indicating\nthat all three groups seek shade at midday and that\nlight activation of the suprachiasmatic nucleus\nis maximal in the morning. Napping occurred\non \u003c7% of days in winter and \u003c22% of days in summer.\nMimicking aspects of the natural environment\nmight be effective in treating certain modern sleep\ndisorders.","internal_url":"https://www.academia.edu/16877852/Natural_sleep_and_its_seasonal_variants_in_three_pre_industrial_societies","translated_internal_url":"","created_at":"2015-10-16T07:49:40.632-07:00","preview_url":null,"current_user_can_edit":null,"current_user_is_owner":null,"owner_id":5641726,"coauthors_can_edit":true,"document_type":"paper","co_author_tags":[{"id":7367113,"work_id":16877852,"tagging_user_id":5641726,"tagged_user_id":40839284,"co_author_invite_id":1469068,"email":"j***l@ucla.edu","display_order":0,"name":"Jerome Siegel","title":"Natural sleep and its seasonal variants in three pre-industrial societies"},{"id":7367114,"work_id":16877852,"tagging_user_id":5641726,"tagged_user_id":28373658,"co_author_invite_id":null,"email":"h***n@gmail.com","display_order":4194304,"name":"Hillard Kaplan","title":"Natural sleep and its seasonal variants in three pre-industrial societies"},{"id":7367115,"work_id":16877852,"tagging_user_id":5641726,"tagged_user_id":37905717,"co_author_invite_id":128060,"email":"g***n@anth.ucsb.edu","affiliation":"University of California, Santa Barbara","display_order":6291456,"name":"Michael Gurven","title":"Natural sleep and its seasonal variants in three pre-industrial societies"},{"id":7367116,"work_id":16877852,"tagging_user_id":5641726,"tagged_user_id":573491,"co_author_invite_id":null,"email":"b***n@e-flux.com","display_order":7340032,"name":"Brian K Wood","title":"Natural sleep and its seasonal variants in three pre-industrial societies"},{"id":7367117,"work_id":16877852,"tagging_user_id":5641726,"tagged_user_id":104679,"co_author_invite_id":null,"email":"h***r@artsci.wustl.edu","affiliation":"Washington University in St. Louis","display_order":7864320,"name":"Herman Pontzer","title":"Natural sleep and its seasonal variants in three pre-industrial societies"},{"id":7367118,"work_id":16877852,"tagging_user_id":5641726,"tagged_user_id":49633380,"co_author_invite_id":535200,"email":"p***r@wits.ac.za","display_order":8126464,"name":"Paul Manger","title":"Natural sleep and its seasonal variants in three pre-industrial societies"},{"id":7367119,"work_id":16877852,"tagging_user_id":5641726,"tagged_user_id":36419400,"co_author_invite_id":1645709,"email":"c***n@mednet.ucla.edu","display_order":8257536,"name":"Charles Wilson","title":"Natural sleep and its seasonal variants in three pre-industrial societies"},{"id":7367120,"work_id":16877852,"tagging_user_id":5641726,"tagged_user_id":36417770,"co_author_invite_id":1645710,"email":"i***3@gmail.com","display_order":8323072,"name":"ronald mcgregor","title":"Natural sleep and its seasonal variants in three pre-industrial societies"}],"downloadable_attachments":[{"id":39233258,"title":"","file_type":"pdf","scribd_thumbnail_url":"https://attachments.academia-assets.com/39233258/thumbnails/1.jpg","file_name":"15_preindustrial_current_biology.pdf","download_url":"https://www.academia.edu/attachments/39233258/download_file","bulk_download_file_name":"Natural_sleep_and_its_seasonal_variants.pdf","bulk_download_url":"https://d1wqtxts1xzle7.cloudfront.net/39233258/15_preindustrial_current_biology-libre.pdf?1445006645=\u0026response-content-disposition=attachment%3B+filename%3DNatural_sleep_and_its_seasonal_variants.pdf\u0026Expires=1743049091\u0026Signature=GOV6TxvbxbZuWn0MsKzXXx2xsiDHuAlrgtbckMKyICgYaouyze-s7sLVSEll7ixji~8ofFVr43yiAr9DxJG9nPzRsThyOK2HD8-zfSR7y-ypCjbmpGLWy8SLIGwpFLrOxKXv~Z6kz1kKQQHrpvLRFAsPuVAtuf4dD4hpWeVVrDW-vwge-Ivz69vK-pxwXoCTCKtPNndwvKaMKHxw6tglhG~p4dxM3Qb0qy~uFqjqOwiasFrzkse8txG1TQL7xPJUrIoEI5I9fN0jONfzXC2yacGuoRyzbvsQ2x3qJbipHOIj-4oaEJEjwAZZMK2sbxioj1EQuIc9S7yFxritwqufbg__\u0026Key-Pair-Id=APKAJLOHF5GGSLRBV4ZA"}],"slug":"Natural_sleep_and_its_seasonal_variants_in_three_pre_industrial_societies","translated_slug":"","page_count":22,"language":"en","content_type":"Work","summary":"How did humans sleep before the modern era?\nBecause the tools to measure sleep under natural\nconditions were developed long after the invention\nof the electric devices suspected of delaying and\nreducing sleep, we investigated sleep in three preindustrial\nsocieties [1–3]. We find that all three show\nsimilar sleep organization, suggesting that they\nexpress core human sleep patterns, most likely characteristic\nof pre-modern era Homo sapiens. Sleep\nperiods, the times from onset to offset, averaged\n6.9–8.5 hr, with sleep durations of 5.7–7.1 hr,\namounts near the low end of those industrial societies\n[4–7]. There was a difference of nearly 1 hr between\nsummer and winter sleep. Daily variation in\nsleep duration was strongly linked to time of onset,\nrather than offset. None of these groups began sleep\nnear sunset, onset occurring, on average, 3.3 hr after\nsunset. Awakening was usually before sunrise. The\nsleep period consistently occurred during the nighttime\nperiod of falling environmental temperature,\nwas not interrupted by extended periods of waking,\nand terminated, with vasoconstriction, near the nadir\nof daily ambient temperature. The daily cycle of temperature\nchange, largely eliminated from modern\nsleep environments, may be a potent natural regulator\nof sleep. Light exposure was maximal in the\nmorning and greatly decreased at noon, indicating\nthat all three groups seek shade at midday and that\nlight activation of the suprachiasmatic nucleus\nis maximal in the morning. Napping occurred\non \u003c7% of days in winter and \u003c22% of days in summer.\nMimicking aspects of the natural environment\nmight be effective in treating certain modern sleep\ndisorders.","owner":{"id":5641726,"first_name":"Gandhi","middle_initials":null,"last_name":"Yetish","page_name":"GandhiYetish","domain_name":"ucla","created_at":"2013-09-19T08:22:04.517-07:00","display_name":"Gandhi Yetish","url":"https://ucla.academia.edu/GandhiYetish"},"attachments":[{"id":39233258,"title":"","file_type":"pdf","scribd_thumbnail_url":"https://attachments.academia-assets.com/39233258/thumbnails/1.jpg","file_name":"15_preindustrial_current_biology.pdf","download_url":"https://www.academia.edu/attachments/39233258/download_file","bulk_download_file_name":"Natural_sleep_and_its_seasonal_variants.pdf","bulk_download_url":"https://d1wqtxts1xzle7.cloudfront.net/39233258/15_preindustrial_current_biology-libre.pdf?1445006645=\u0026response-content-disposition=attachment%3B+filename%3DNatural_sleep_and_its_seasonal_variants.pdf\u0026Expires=1743049091\u0026Signature=GOV6TxvbxbZuWn0MsKzXXx2xsiDHuAlrgtbckMKyICgYaouyze-s7sLVSEll7ixji~8ofFVr43yiAr9DxJG9nPzRsThyOK2HD8-zfSR7y-ypCjbmpGLWy8SLIGwpFLrOxKXv~Z6kz1kKQQHrpvLRFAsPuVAtuf4dD4hpWeVVrDW-vwge-Ivz69vK-pxwXoCTCKtPNndwvKaMKHxw6tglhG~p4dxM3Qb0qy~uFqjqOwiasFrzkse8txG1TQL7xPJUrIoEI5I9fN0jONfzXC2yacGuoRyzbvsQ2x3qJbipHOIj-4oaEJEjwAZZMK2sbxioj1EQuIc9S7yFxritwqufbg__\u0026Key-Pair-Id=APKAJLOHF5GGSLRBV4ZA"}],"research_interests":[{"id":18594,"name":"Evolutionary Ecology","url":"https://www.academia.edu/Documents/in/Evolutionary_Ecology"},{"id":27315,"name":"Sleep \u0026 Circadian Rhythms","url":"https://www.academia.edu/Documents/in/Sleep_and_Circadian_Rhythms"},{"id":32948,"name":"Hunter-Gatherers (Anthropology)","url":"https://www.academia.edu/Documents/in/Hunter-Gatherers_Anthropology_"},{"id":133324,"name":"Sleep","url":"https://www.academia.edu/Documents/in/Sleep"},{"id":139554,"name":"Accelerometry","url":"https://www.academia.edu/Documents/in/Accelerometry"}],"urls":[]}, dispatcherData: dispatcherData }); $(this).data('initialized', true); } }); $a.trackClickSource(".js-work-strip-work-link", "profile_work_strip") }); </script> </div><div class="profile--tab_content_container js-tab-pane tab-pane" data-section-id="3766399" id="papers"><div class="js-work-strip profile--work_container" data-work-id="30242563"><div class="profile--work_thumbnail hidden-xs"><a class="js-work-strip-work-link" data-click-track="profile-work-strip-thumbnail" href="https://www.academia.edu/30242563/What_is_segmented_sleep_Actigraphy_field_validation_for_daytime_sleep_and_nighttime_wake"><img alt="Research paper thumbnail of What is segmented sleep? Actigraphy field validation for daytime sleep and nighttime wake" class="work-thumbnail" src="https://a.academia-assets.com/images/blank-paper.jpg" /></a></div><div class="wp-workCard wp-workCard_itemContainer"><div class="wp-workCard_item wp-workCard--title"><a class="js-work-strip-work-link text-gray-darker" data-click-track="profile-work-strip-title" href="https://www.academia.edu/30242563/What_is_segmented_sleep_Actigraphy_field_validation_for_daytime_sleep_and_nighttime_wake">What is segmented sleep? Actigraphy field validation for daytime sleep and nighttime wake</a></div><div class="wp-workCard_item wp-workCard--coauthors"><span>by </span><span><a class="" data-click-track="profile-work-strip-authors" href="https://utoronto.academia.edu/DavidSamson">David Samson</a> and <a class="" data-click-track="profile-work-strip-authors" href="https://ucla.academia.edu/GandhiYetish">Gandhi Yetish</a></span></div><div class="wp-workCard_item"><span class="js-work-more-abstract-truncated">Objective: To compare different scoring parameter settings in actigraphy software for inferring s...</span><a class="js-work-more-abstract" data-broccoli-component="work_strip.more_abstract" data-click-track="profile-work-strip-more-abstract" href="javascript:;"><span> more </span><span><i class="fa fa-caret-down"></i></span></a><span class="js-work-more-abstract-untruncated hidden">Objective: To compare different scoring parameter settings in actigraphy software for inferring sleep and<br />wake bouts for validating analytical techniques outside of laboratory environments.<br />Design: To identify parameter settings that best identify napping during periods of wakefulness, we<br />analyzed 137 days on which participants reported daytime napping, as compared with a random subset<br />of 30 days when no naps were reported. To identify settings that identify periods of wakefulness during<br />sleep,we used data from a subsample of women who reported discrete wake bouts while nursing at night.<br />Setting: Equatorial Tanzania in January to February 2016.<br />Participants: The Hadza—a non-industrial foraging population.<br />Measurements: Thirty-three subjects participated in the study for 393 observation days. Using the Bland-<br />Altman technique to determine concordance, we analyzed reported events of daytime napping and nighttime<br />wake bouts.<br />Results: Only 1 parameter setting could reliably detect reported naps (15-minute nap length, ≤50 counts).<br />Moreover, of the 6 tested parameter settings to detect wake bouts, the setting where the sleep-wake<br />algorithm was parameterized to detect 20 consecutive minutes throughout the designated sleep period<br />did not overestimate or underestimate wake bouts, had the lowest mean difference, and did not<br />significantly differ from reported wake-bout events.<br />Conclusion: We propose operational definitions for multiple dimensions of segmented sleep and conclude<br />that actigraphy is an effective method for detecting segmented sleep in future cross-site comparative<br />research. The implications of such work are far reaching, as sleep research in preindustrial and developing<br />societies is documenting natural sleep-wake patterns in previously inaccessible environments.</span></div><div class="wp-workCard_item wp-workCard--actions"><span class="work-strip-bookmark-button-container"></span><a id="df41c0aa4012caf96ca8582a9c511f31" class="wp-workCard--action" rel="nofollow" data-click-track="profile-work-strip-download" data-download="{"attachment_id":50707569,"asset_id":30242563,"asset_type":"Work","button_location":"profile"}" href="https://www.academia.edu/attachments/50707569/download_file?s=profile"><span><i class="fa fa-arrow-down"></i></span><span>Download</span></a><span class="wp-workCard--action visible-if-viewed-by-owner inline-block" style="display: none;"><span class="js-profile-work-strip-edit-button-wrapper profile-work-strip-edit-button-wrapper" data-work-id="30242563"><a class="js-profile-work-strip-edit-button" tabindex="0"><span><i class="fa fa-pencil"></i></span><span>Edit</span></a></span></span></div><div class="wp-workCard_item wp-workCard--stats"><span><span><span class="js-view-count view-count u-mr2x" data-work-id="30242563"><i class="fa fa-spinner fa-spin"></i></span><script>$(function () { var workId = 30242563; window.Academia.workViewCountsFetcher.queue(workId, function (count) { var description = window.$h.commaizeInt(count) + " " + window.$h.pluralize(count, 'View'); $(".js-view-count[data-work-id=30242563]").text(description); $(".js-view-count[data-work-id=30242563]").attr('title', description).tooltip(); }); });</script></span></span><span><span class="percentile-widget hidden"><span class="u-mr2x work-percentile"></span></span><script>$(function () { var workId = 30242563; window.Academia.workPercentilesFetcher.queue(workId, function (percentileText) { var container = $(".js-work-strip[data-work-id='30242563']"); container.find('.work-percentile').text(percentileText.charAt(0).toUpperCase() + percentileText.slice(1)); container.find('.percentile-widget').show(); container.find('.percentile-widget').removeClass('hidden'); }); });</script></span></div><div id="work-strip-premium-row-container"></div></div></div><script> require.config({ waitSeconds: 90 })(["https://a.academia-assets.com/assets/wow_profile-a9bf3a2bc8c89fa2a77156577594264ee8a0f214d74241bc0fcd3f69f8d107ac.js","https://a.academia-assets.com/assets/work_edit-ad038b8c047c1a8d4fa01b402d530ff93c45fee2137a149a4a5398bc8ad67560.js"], function() { // from javascript_helper.rb var dispatcherData = {} if (true){ window.WowProfile.dispatcher = window.WowProfile.dispatcher || _.clone(Backbone.Events); dispatcherData = { dispatcher: window.WowProfile.dispatcher, downloadLinkId: "df41c0aa4012caf96ca8582a9c511f31" } } $('.js-work-strip[data-work-id=30242563]').each(function() { if (!$(this).data('initialized')) { new WowProfile.WorkStripView({ el: this, workJSON: {"id":30242563,"title":"What is segmented sleep? Actigraphy field validation for daytime sleep and nighttime wake","translated_title":"","metadata":{"abstract":"Objective: To compare different scoring parameter settings in actigraphy software for inferring sleep and\nwake bouts for validating analytical techniques outside of laboratory environments.\nDesign: To identify parameter settings that best identify napping during periods of wakefulness, we\nanalyzed 137 days on which participants reported daytime napping, as compared with a random subset\nof 30 days when no naps were reported. To identify settings that identify periods of wakefulness during\nsleep,we used data from a subsample of women who reported discrete wake bouts while nursing at night.\nSetting: Equatorial Tanzania in January to February 2016.\nParticipants: The Hadza—a non-industrial foraging population.\nMeasurements: Thirty-three subjects participated in the study for 393 observation days. Using the Bland-\nAltman technique to determine concordance, we analyzed reported events of daytime napping and nighttime\nwake bouts.\nResults: Only 1 parameter setting could reliably detect reported naps (15-minute nap length, ≤50 counts).\nMoreover, of the 6 tested parameter settings to detect wake bouts, the setting where the sleep-wake\nalgorithm was parameterized to detect 20 consecutive minutes throughout the designated sleep period\ndid not overestimate or underestimate wake bouts, had the lowest mean difference, and did not\nsignificantly differ from reported wake-bout events.\nConclusion: We propose operational definitions for multiple dimensions of segmented sleep and conclude\nthat actigraphy is an effective method for detecting segmented sleep in future cross-site comparative\nresearch. The implications of such work are far reaching, as sleep research in preindustrial and developing\nsocieties is documenting natural sleep-wake patterns in previously inaccessible environments.\n"},"translated_abstract":"Objective: To compare different scoring parameter settings in actigraphy software for inferring sleep and\nwake bouts for validating analytical techniques outside of laboratory environments.\nDesign: To identify parameter settings that best identify napping during periods of wakefulness, we\nanalyzed 137 days on which participants reported daytime napping, as compared with a random subset\nof 30 days when no naps were reported. To identify settings that identify periods of wakefulness during\nsleep,we used data from a subsample of women who reported discrete wake bouts while nursing at night.\nSetting: Equatorial Tanzania in January to February 2016.\nParticipants: The Hadza—a non-industrial foraging population.\nMeasurements: Thirty-three subjects participated in the study for 393 observation days. Using the Bland-\nAltman technique to determine concordance, we analyzed reported events of daytime napping and nighttime\nwake bouts.\nResults: Only 1 parameter setting could reliably detect reported naps (15-minute nap length, ≤50 counts).\nMoreover, of the 6 tested parameter settings to detect wake bouts, the setting where the sleep-wake\nalgorithm was parameterized to detect 20 consecutive minutes throughout the designated sleep period\ndid not overestimate or underestimate wake bouts, had the lowest mean difference, and did not\nsignificantly differ from reported wake-bout events.\nConclusion: We propose operational definitions for multiple dimensions of segmented sleep and conclude\nthat actigraphy is an effective method for detecting segmented sleep in future cross-site comparative\nresearch. The implications of such work are far reaching, as sleep research in preindustrial and developing\nsocieties is documenting natural sleep-wake patterns in previously inaccessible environments.\n","internal_url":"https://www.academia.edu/30242563/What_is_segmented_sleep_Actigraphy_field_validation_for_daytime_sleep_and_nighttime_wake","translated_internal_url":"","created_at":"2016-12-04T08:01:02.434-08:00","preview_url":null,"current_user_can_edit":null,"current_user_is_owner":null,"owner_id":671632,"coauthors_can_edit":true,"document_type":"paper","co_author_tags":[{"id":26371539,"work_id":30242563,"tagging_user_id":671632,"tagged_user_id":5641726,"co_author_invite_id":null,"email":"g***i@yetish.com","affiliation":"University of California, Los Angeles","display_order":1,"name":"Gandhi Yetish","title":"What is segmented sleep? Actigraphy field validation for daytime sleep and nighttime wake"},{"id":26371540,"work_id":30242563,"tagging_user_id":671632,"tagged_user_id":12240488,"co_author_invite_id":null,"email":"a***n@gmail.com","affiliation":"University of Nevada, Las Vegas","display_order":2,"name":"Alyssa N Crittenden","title":"What is segmented sleep? Actigraphy field validation for daytime sleep and nighttime wake"},{"id":26371541,"work_id":30242563,"tagging_user_id":671632,"tagged_user_id":41527569,"co_author_invite_id":null,"email":"c***n@gmail.com","display_order":3,"name":"Charles Nunn","title":"What is segmented sleep? Actigraphy field validation for daytime sleep and nighttime wake"},{"id":26371542,"work_id":30242563,"tagging_user_id":671632,"tagged_user_id":3356724,"co_author_invite_id":null,"email":"i***a@yahoo.com","display_order":4,"name":"Ibrahim A Mabulla","title":"What is segmented sleep? 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To identify settings that identify periods of wakefulness during\nsleep,we used data from a subsample of women who reported discrete wake bouts while nursing at night.\nSetting: Equatorial Tanzania in January to February 2016.\nParticipants: The Hadza—a non-industrial foraging population.\nMeasurements: Thirty-three subjects participated in the study for 393 observation days. Using the Bland-\nAltman technique to determine concordance, we analyzed reported events of daytime napping and nighttime\nwake bouts.\nResults: Only 1 parameter setting could reliably detect reported naps (15-minute nap length, ≤50 counts).\nMoreover, of the 6 tested parameter settings to detect wake bouts, the setting where the sleep-wake\nalgorithm was parameterized to detect 20 consecutive minutes throughout the designated sleep period\ndid not overestimate or underestimate wake bouts, had the lowest mean difference, and did not\nsignificantly differ from reported wake-bout events.\nConclusion: We propose operational definitions for multiple dimensions of segmented sleep and conclude\nthat actigraphy is an effective method for detecting segmented sleep in future cross-site comparative\nresearch. The implications of such work are far reaching, as sleep research in preindustrial and developing\nsocieties is documenting natural sleep-wake patterns in previously inaccessible environments.\n","owner":{"id":671632,"first_name":"David","middle_initials":null,"last_name":"Samson","page_name":"DavidSamson","domain_name":"utoronto","created_at":"2011-08-17T03:13:26.908-07:00","display_name":"David Samson","url":"https://utoronto.academia.edu/DavidSamson"},"attachments":[{"id":50707569,"title":"","file_type":"pdf","scribd_thumbnail_url":"https://a.academia-assets.com/images/blank-paper.jpg","file_name":"Samson_et_al._2016_What_is_segmented_sleep_Actigraphy_field_validation_for_daytime_sleep_and_nighttime_wake.pdf","download_url":"https://www.academia.edu/attachments/50707569/download_file","bulk_download_file_name":"What_is_segmented_sleep_Actigraphy_field.pdf","bulk_download_url":"https://d1wqtxts1xzle7.cloudfront.net/50707569/Samson_et_al._2016_What_is_segmented_sleep_Actigraphy_field_validation_for_daytime_sleep_and_nighttime_wake-libre.pdf?1480867378=\u0026response-content-disposition=attachment%3B+filename%3DWhat_is_segmented_sleep_Actigraphy_field.pdf\u0026Expires=1743222881\u0026Signature=VIfvFiCUqFP~k~Cbmarw6GDHcHtTYIGfbBhAWinZifGfga~e7Ni1Fqadz5O4tdSqg6tB1E1vlT0AnMYqx9kPmI32uNk8QlwxBXME6mo4HPLujVapNxVssYR9UM69b2xth~T~-tw1iad3aYkXYWCLBf0Ziuvlt-0Xq57b4fr5KXrh5-zDin-TShC8I2ihWAmBvAxg74J7Kuje3qUrSj1neyHFMDpX~q4UkBMmxiHgY1mvq8UACC5dYMzXVrlk7GnBAsICd8khukuoo62EwpoQy2X6kX5G3xcDHbVcnaVSFnzOxy1J26zb20jXQVDgSyfA4qB1w3W5lSOPTrEseQmwKQ__\u0026Key-Pair-Id=APKAJLOHF5GGSLRBV4ZA"}],"research_interests":[{"id":32948,"name":"Hunter-Gatherers (Anthropology)","url":"https://www.academia.edu/Documents/in/Hunter-Gatherers_Anthropology_"},{"id":61109,"name":"Validation","url":"https://www.academia.edu/Documents/in/Validation"},{"id":133324,"name":"Sleep","url":"https://www.academia.edu/Documents/in/Sleep"},{"id":276765,"name":"Actigraphy","url":"https://www.academia.edu/Documents/in/Actigraphy"},{"id":330336,"name":"Research in the field of IT Engineering/ Electronics Engineering","url":"https://www.academia.edu/Documents/in/Research_in_the_field_of_IT_Engineering_Electronics_Engineering"}],"urls":[]}, dispatcherData: dispatcherData }); $(this).data('initialized', true); } }); $a.trackClickSource(".js-work-strip-work-link", "profile_work_strip") if (false) { Aedu.setUpFigureCarousel('profile-work-30242563-figures'); } }); </script> <div class="js-work-strip profile--work_container" data-work-id="16943541"><div class="profile--work_thumbnail hidden-xs"><a class="js-work-strip-work-link" data-click-track="profile-work-strip-thumbnail" href="https://www.academia.edu/16943541/Patterns_of_senescence_in_human_cardiovascular_fitness_VO_2_max_in_subsistence_and_industrialized_populations"><img alt="Research paper thumbnail of Patterns of senescence in human cardiovascular fitness: VO 2 max in subsistence and industrialized populations" class="work-thumbnail" src="https://attachments.academia-assets.com/39269714/thumbnails/1.jpg" /></a></div><div class="wp-workCard wp-workCard_itemContainer"><div class="wp-workCard_item wp-workCard--title"><a class="js-work-strip-work-link text-gray-darker" data-click-track="profile-work-strip-title" href="https://www.academia.edu/16943541/Patterns_of_senescence_in_human_cardiovascular_fitness_VO_2_max_in_subsistence_and_industrialized_populations">Patterns of senescence in human cardiovascular fitness: VO 2 max in subsistence and industrialized populations</a></div><div class="wp-workCard_item"><span>American Journal of Human Biology</span><span>, 2013</span></div><div class="wp-workCard_item"><span class="js-work-more-abstract-truncated">Objectives: This study explores whether cardiovascular fitness levels and senescent decline are s...</span><a class="js-work-more-abstract" data-broccoli-component="work_strip.more_abstract" data-click-track="profile-work-strip-more-abstract" href="javascript:;"><span> more </span><span><i class="fa fa-caret-down"></i></span></a><span class="js-work-more-abstract-untruncated hidden">Objectives: This study explores whether cardiovascular fitness levels and senescent decline are similar in the Tsimane of Bolivia and Canadians, as well as other subsistence and industrialized populations. Among Tsimane, we examine whether morbidity predicts lower levels and faster decline of cardiovascular fitness, or whether their lifestyle (e.g., high physical activity) promotes high levels and slow decline. Alternatively, high activity levels and morbidity might counterbalance such that Tsimane fitness levels and decline are similar to those in industrialized populations.</span></div><div class="wp-workCard_item wp-workCard--actions"><span class="work-strip-bookmark-button-container"></span><a id="e43c40f562e2c45da7e46a51bfa70e62" class="wp-workCard--action" rel="nofollow" data-click-track="profile-work-strip-download" data-download="{"attachment_id":39269714,"asset_id":16943541,"asset_type":"Work","button_location":"profile"}" href="https://www.academia.edu/attachments/39269714/download_file?s=profile"><span><i class="fa fa-arrow-down"></i></span><span>Download</span></a><span class="wp-workCard--action visible-if-viewed-by-owner inline-block" style="display: none;"><span class="js-profile-work-strip-edit-button-wrapper profile-work-strip-edit-button-wrapper" data-work-id="16943541"><a class="js-profile-work-strip-edit-button" tabindex="0"><span><i class="fa fa-pencil"></i></span><span>Edit</span></a></span></span></div><div class="wp-workCard_item wp-workCard--stats"><span><span><span class="js-view-count view-count u-mr2x" data-work-id="16943541"><i class="fa fa-spinner fa-spin"></i></span><script>$(function () { var workId = 16943541; window.Academia.workViewCountsFetcher.queue(workId, function (count) { var description = window.$h.commaizeInt(count) + " " + window.$h.pluralize(count, 'View'); $(".js-view-count[data-work-id=16943541]").text(description); $(".js-view-count[data-work-id=16943541]").attr('title', description).tooltip(); }); });</script></span></span><span><span class="percentile-widget hidden"><span class="u-mr2x work-percentile"></span></span><script>$(function () { var workId = 16943541; window.Academia.workPercentilesFetcher.queue(workId, function (percentileText) { var container = $(".js-work-strip[data-work-id='16943541']"); container.find('.work-percentile').text(percentileText.charAt(0).toUpperCase() + percentileText.slice(1)); container.find('.percentile-widget').show(); container.find('.percentile-widget').removeClass('hidden'); }); });</script></span></div><div id="work-strip-premium-row-container"></div></div></div><script> require.config({ waitSeconds: 90 })(["https://a.academia-assets.com/assets/wow_profile-a9bf3a2bc8c89fa2a77156577594264ee8a0f214d74241bc0fcd3f69f8d107ac.js","https://a.academia-assets.com/assets/work_edit-ad038b8c047c1a8d4fa01b402d530ff93c45fee2137a149a4a5398bc8ad67560.js"], function() { // from javascript_helper.rb var dispatcherData = {} if (true){ window.WowProfile.dispatcher = window.WowProfile.dispatcher || _.clone(Backbone.Events); dispatcherData = { dispatcher: window.WowProfile.dispatcher, downloadLinkId: "e43c40f562e2c45da7e46a51bfa70e62" } } $('.js-work-strip[data-work-id=16943541]').each(function() { if (!$(this).data('initialized')) { new WowProfile.WorkStripView({ el: this, workJSON: {"id":16943541,"title":"Patterns of senescence in human cardiovascular fitness: VO 2 max in subsistence and industrialized populations","translated_title":"","metadata":{"ai_title_tag":"Cardiovascular Fitness in Aging Populations","grobid_abstract":"Objectives: This study explores whether cardiovascular fitness levels and senescent decline are similar in the Tsimane of Bolivia and Canadians, as well as other subsistence and industrialized populations. Among Tsimane, we examine whether morbidity predicts lower levels and faster decline of cardiovascular fitness, or whether their lifestyle (e.g., high physical activity) promotes high levels and slow decline. Alternatively, high activity levels and morbidity might counterbalance such that Tsimane fitness levels and decline are similar to those in industrialized populations.","publication_date":{"day":null,"month":null,"year":2013,"errors":{}},"publication_name":"American Journal of Human Biology","grobid_abstract_attachment_id":39269714},"translated_abstract":null,"internal_url":"https://www.academia.edu/16943541/Patterns_of_senescence_in_human_cardiovascular_fitness_VO_2_max_in_subsistence_and_industrialized_populations","translated_internal_url":"","created_at":"2015-10-18T05:22:42.942-07:00","preview_url":null,"current_user_can_edit":null,"current_user_is_owner":null,"owner_id":5641726,"coauthors_can_edit":true,"document_type":"paper","co_author_tags":[],"downloadable_attachments":[{"id":39269714,"title":"","file_type":"pdf","scribd_thumbnail_url":"https://attachments.academia-assets.com/39269714/thumbnails/1.jpg","file_name":"00b7d52332edb5e718000000.pdf","download_url":"https://www.academia.edu/attachments/39269714/download_file","bulk_download_file_name":"Patterns_of_senescence_in_human_cardiova.pdf","bulk_download_url":"https://d1wqtxts1xzle7.cloudfront.net/39269714/00b7d52332edb5e718000000-libre.pdf?1445170985=\u0026response-content-disposition=attachment%3B+filename%3DPatterns_of_senescence_in_human_cardiova.pdf\u0026Expires=1743222881\u0026Signature=Py7TGrKy37CZZPPVWOTcoOwutVMfGf6i8Fhlc~mQSC3BLYha6mMeqEhCs~tVjoaLJc-S2bz77OIOX45vKdv7ji-9EEkxe6faFSAronPLlMxhcXRddtQVpN9WX1~ky7w58L-ZT8MgrN2nrGnbPfa8YcXsesRMSXdncrMQOC-gozsKNuWXKBaSVQoyMzdLZ491oz-sKbSbFB2QNSsFM07lH5rvZDWA-Dcun5b8GcgR7Rm6w8qJMzI91BZWusJH~uA~Jg3CmqjxS9BS4E0fsfC3iQBoOmOJV6qHLEEpshBcQD7sCXhL9UcScQ~qqgNPl-2la6LvDnq~NS1-6Ez7H4uvug__\u0026Key-Pair-Id=APKAJLOHF5GGSLRBV4ZA"}],"slug":"Patterns_of_senescence_in_human_cardiovascular_fitness_VO_2_max_in_subsistence_and_industrialized_populations","translated_slug":"","page_count":14,"language":"en","content_type":"Work","summary":"Objectives: This study explores whether cardiovascular fitness levels and senescent decline are similar in the Tsimane of Bolivia and Canadians, as well as other subsistence and industrialized populations. Among Tsimane, we examine whether morbidity predicts lower levels and faster decline of cardiovascular fitness, or whether their lifestyle (e.g., high physical activity) promotes high levels and slow decline. Alternatively, high activity levels and morbidity might counterbalance such that Tsimane fitness levels and decline are similar to those in industrialized populations.","owner":{"id":5641726,"first_name":"Gandhi","middle_initials":null,"last_name":"Yetish","page_name":"GandhiYetish","domain_name":"ucla","created_at":"2013-09-19T08:22:04.517-07:00","display_name":"Gandhi Yetish","url":"https://ucla.academia.edu/GandhiYetish"},"attachments":[{"id":39269714,"title":"","file_type":"pdf","scribd_thumbnail_url":"https://attachments.academia-assets.com/39269714/thumbnails/1.jpg","file_name":"00b7d52332edb5e718000000.pdf","download_url":"https://www.academia.edu/attachments/39269714/download_file","bulk_download_file_name":"Patterns_of_senescence_in_human_cardiova.pdf","bulk_download_url":"https://d1wqtxts1xzle7.cloudfront.net/39269714/00b7d52332edb5e718000000-libre.pdf?1445170985=\u0026response-content-disposition=attachment%3B+filename%3DPatterns_of_senescence_in_human_cardiova.pdf\u0026Expires=1743222881\u0026Signature=Py7TGrKy37CZZPPVWOTcoOwutVMfGf6i8Fhlc~mQSC3BLYha6mMeqEhCs~tVjoaLJc-S2bz77OIOX45vKdv7ji-9EEkxe6faFSAronPLlMxhcXRddtQVpN9WX1~ky7w58L-ZT8MgrN2nrGnbPfa8YcXsesRMSXdncrMQOC-gozsKNuWXKBaSVQoyMzdLZ491oz-sKbSbFB2QNSsFM07lH5rvZDWA-Dcun5b8GcgR7Rm6w8qJMzI91BZWusJH~uA~Jg3CmqjxS9BS4E0fsfC3iQBoOmOJV6qHLEEpshBcQD7sCXhL9UcScQ~qqgNPl-2la6LvDnq~NS1-6Ez7H4uvug__\u0026Key-Pair-Id=APKAJLOHF5GGSLRBV4ZA"}],"research_interests":[{"id":155,"name":"Evolutionary Biology","url":"https://www.academia.edu/Documents/in/Evolutionary_Biology"},{"id":591,"name":"Nutrition and Dietetics","url":"https://www.academia.edu/Documents/in/Nutrition_and_Dietetics"},{"id":767,"name":"Anthropology","url":"https://www.academia.edu/Documents/in/Anthropology"},{"id":6791,"name":"Aging","url":"https://www.academia.edu/Documents/in/Aging"},{"id":7471,"name":"Life Style","url":"https://www.academia.edu/Documents/in/Life_Style"},{"id":9815,"name":"Developing Countries","url":"https://www.academia.edu/Documents/in/Developing_Countries"},{"id":11552,"name":"Bolivia","url":"https://www.academia.edu/Documents/in/Bolivia"},{"id":22506,"name":"Adolescent","url":"https://www.academia.edu/Documents/in/Adolescent"},{"id":54114,"name":"Canada","url":"https://www.academia.edu/Documents/in/Canada"},{"id":91707,"name":"American Journal of Human Biology","url":"https://www.academia.edu/Documents/in/American_Journal_of_Human_Biology"},{"id":131298,"name":"Heart rate","url":"https://www.academia.edu/Documents/in/Heart_rate"},{"id":133057,"name":"Young Adult","url":"https://www.academia.edu/Documents/in/Young_Adult"},{"id":268784,"name":"Physical Fitness","url":"https://www.academia.edu/Documents/in/Physical_Fitness"},{"id":289271,"name":"Aged","url":"https://www.academia.edu/Documents/in/Aged"},{"id":311522,"name":"Developed Countries","url":"https://www.academia.edu/Documents/in/Developed_Countries"},{"id":559242,"name":"Cardiovascular Diseases","url":"https://www.academia.edu/Documents/in/Cardiovascular_Diseases"},{"id":1034181,"name":"Cross Sectional Studies","url":"https://www.academia.edu/Documents/in/Cross_Sectional_Studies"},{"id":1146831,"name":"Exercise Test","url":"https://www.academia.edu/Documents/in/Exercise_Test"},{"id":1193624,"name":"Oxygen Consumption","url":"https://www.academia.edu/Documents/in/Oxygen_Consumption"}],"urls":[]}, dispatcherData: dispatcherData }); $(this).data('initialized', true); } }); $a.trackClickSource(".js-work-strip-work-link", "profile_work_strip") if (false) { Aedu.setUpFigureCarousel('profile-work-16943541-figures'); } }); </script> <div class="js-work-strip profile--work_container" data-work-id="16877852"><div class="profile--work_thumbnail hidden-xs"><a class="js-work-strip-work-link" data-click-track="profile-work-strip-thumbnail" href="https://www.academia.edu/16877852/Natural_sleep_and_its_seasonal_variants_in_three_pre_industrial_societies"><img alt="Research paper thumbnail of Natural sleep and its seasonal variants in three pre-industrial societies" class="work-thumbnail" src="https://attachments.academia-assets.com/39233258/thumbnails/1.jpg" /></a></div><div class="wp-workCard wp-workCard_itemContainer"><div class="wp-workCard_item wp-workCard--title"><a class="js-work-strip-work-link text-gray-darker" data-click-track="profile-work-strip-title" href="https://www.academia.edu/16877852/Natural_sleep_and_its_seasonal_variants_in_three_pre_industrial_societies">Natural sleep and its seasonal variants in three pre-industrial societies</a></div><div class="wp-workCard_item wp-workCard--coauthors"><span>by </span><span><a class="" data-click-track="profile-work-strip-authors" href="https://ucla.academia.edu/GandhiYetish">Gandhi Yetish</a>, <a class="" data-click-track="profile-work-strip-authors" href="https://independent.academia.edu/HillardKaplan">Hillard Kaplan</a>, <a class="" data-click-track="profile-work-strip-authors" href="https://independent.academia.edu/CharlesWilson26">Charles Wilson</a>, and <a class="" data-click-track="profile-work-strip-authors" href="https://independent.academia.edu/ronaldmcgregor">ronald mcgregor</a></span></div><div class="wp-workCard_item"><span class="js-work-more-abstract-truncated">How did humans sleep before the modern era? Because the tools to measure sleep under natural cond...</span><a class="js-work-more-abstract" data-broccoli-component="work_strip.more_abstract" data-click-track="profile-work-strip-more-abstract" href="javascript:;"><span> more </span><span><i class="fa fa-caret-down"></i></span></a><span class="js-work-more-abstract-untruncated hidden">How did humans sleep before the modern era?<br />Because the tools to measure sleep under natural<br />conditions were developed long after the invention<br />of the electric devices suspected of delaying and<br />reducing sleep, we investigated sleep in three preindustrial<br />societies [1–3]. We find that all three show<br />similar sleep organization, suggesting that they<br />express core human sleep patterns, most likely characteristic<br />of pre-modern era Homo sapiens. Sleep<br />periods, the times from onset to offset, averaged<br />6.9–8.5 hr, with sleep durations of 5.7–7.1 hr,<br />amounts near the low end of those industrial societies<br />[4–7]. There was a difference of nearly 1 hr between<br />summer and winter sleep. Daily variation in<br />sleep duration was strongly linked to time of onset,<br />rather than offset. None of these groups began sleep<br />near sunset, onset occurring, on average, 3.3 hr after<br />sunset. Awakening was usually before sunrise. The<br />sleep period consistently occurred during the nighttime<br />period of falling environmental temperature,<br />was not interrupted by extended periods of waking,<br />and terminated, with vasoconstriction, near the nadir<br />of daily ambient temperature. The daily cycle of temperature<br />change, largely eliminated from modern<br />sleep environments, may be a potent natural regulator<br />of sleep. Light exposure was maximal in the<br />morning and greatly decreased at noon, indicating<br />that all three groups seek shade at midday and that<br />light activation of the suprachiasmatic nucleus<br />is maximal in the morning. Napping occurred<br />on <7% of days in winter and <22% of days in summer.<br />Mimicking aspects of the natural environment<br />might be effective in treating certain modern sleep<br />disorders.</span></div><div class="wp-workCard_item wp-workCard--actions"><span class="work-strip-bookmark-button-container"></span><a id="fac6b4dbac3bd04ad0916b9081f4c952" class="wp-workCard--action" rel="nofollow" data-click-track="profile-work-strip-download" data-download="{"attachment_id":39233258,"asset_id":16877852,"asset_type":"Work","button_location":"profile"}" href="https://www.academia.edu/attachments/39233258/download_file?s=profile"><span><i class="fa fa-arrow-down"></i></span><span>Download</span></a><span class="wp-workCard--action visible-if-viewed-by-owner inline-block" style="display: none;"><span class="js-profile-work-strip-edit-button-wrapper profile-work-strip-edit-button-wrapper" data-work-id="16877852"><a class="js-profile-work-strip-edit-button" tabindex="0"><span><i class="fa fa-pencil"></i></span><span>Edit</span></a></span></span></div><div class="wp-workCard_item wp-workCard--stats"><span><span><span class="js-view-count view-count u-mr2x" data-work-id="16877852"><i class="fa fa-spinner fa-spin"></i></span><script>$(function () { var workId = 16877852; window.Academia.workViewCountsFetcher.queue(workId, function (count) { var description = window.$h.commaizeInt(count) + " " + window.$h.pluralize(count, 'View'); $(".js-view-count[data-work-id=16877852]").text(description); $(".js-view-count[data-work-id=16877852]").attr('title', description).tooltip(); }); });</script></span></span><span><span class="percentile-widget hidden"><span class="u-mr2x work-percentile"></span></span><script>$(function () { var workId = 16877852; window.Academia.workPercentilesFetcher.queue(workId, function (percentileText) { var container = $(".js-work-strip[data-work-id='16877852']"); container.find('.work-percentile').text(percentileText.charAt(0).toUpperCase() + percentileText.slice(1)); container.find('.percentile-widget').show(); container.find('.percentile-widget').removeClass('hidden'); }); });</script></span></div><div id="work-strip-premium-row-container"></div></div></div><script> require.config({ waitSeconds: 90 })(["https://a.academia-assets.com/assets/wow_profile-a9bf3a2bc8c89fa2a77156577594264ee8a0f214d74241bc0fcd3f69f8d107ac.js","https://a.academia-assets.com/assets/work_edit-ad038b8c047c1a8d4fa01b402d530ff93c45fee2137a149a4a5398bc8ad67560.js"], function() { // from javascript_helper.rb var dispatcherData = {} if (true){ window.WowProfile.dispatcher = window.WowProfile.dispatcher || _.clone(Backbone.Events); dispatcherData = { dispatcher: window.WowProfile.dispatcher, downloadLinkId: "fac6b4dbac3bd04ad0916b9081f4c952" } } $('.js-work-strip[data-work-id=16877852]').each(function() { if (!$(this).data('initialized')) { new WowProfile.WorkStripView({ el: this, workJSON: {"id":16877852,"title":"Natural sleep and its seasonal variants in three pre-industrial societies","translated_title":"","metadata":{"abstract":"How did humans sleep before the modern era?\nBecause the tools to measure sleep under natural\nconditions were developed long after the invention\nof the electric devices suspected of delaying and\nreducing sleep, we investigated sleep in three preindustrial\nsocieties [1–3]. We find that all three show\nsimilar sleep organization, suggesting that they\nexpress core human sleep patterns, most likely characteristic\nof pre-modern era Homo sapiens. Sleep\nperiods, the times from onset to offset, averaged\n6.9–8.5 hr, with sleep durations of 5.7–7.1 hr,\namounts near the low end of those industrial societies\n[4–7]. There was a difference of nearly 1 hr between\nsummer and winter sleep. Daily variation in\nsleep duration was strongly linked to time of onset,\nrather than offset. None of these groups began sleep\nnear sunset, onset occurring, on average, 3.3 hr after\nsunset. Awakening was usually before sunrise. The\nsleep period consistently occurred during the nighttime\nperiod of falling environmental temperature,\nwas not interrupted by extended periods of waking,\nand terminated, with vasoconstriction, near the nadir\nof daily ambient temperature. The daily cycle of temperature\nchange, largely eliminated from modern\nsleep environments, may be a potent natural regulator\nof sleep. Light exposure was maximal in the\nmorning and greatly decreased at noon, indicating\nthat all three groups seek shade at midday and that\nlight activation of the suprachiasmatic nucleus\nis maximal in the morning. Napping occurred\non \u003c7% of days in winter and \u003c22% of days in summer.\nMimicking aspects of the natural environment\nmight be effective in treating certain modern sleep\ndisorders.","ai_title_tag":"Seasonal Sleep Patterns in Pre-Industrial Societies"},"translated_abstract":"How did humans sleep before the modern era?\nBecause the tools to measure sleep under natural\nconditions were developed long after the invention\nof the electric devices suspected of delaying and\nreducing sleep, we investigated sleep in three preindustrial\nsocieties [1–3]. We find that all three show\nsimilar sleep organization, suggesting that they\nexpress core human sleep patterns, most likely characteristic\nof pre-modern era Homo sapiens. Sleep\nperiods, the times from onset to offset, averaged\n6.9–8.5 hr, with sleep durations of 5.7–7.1 hr,\namounts near the low end of those industrial societies\n[4–7]. There was a difference of nearly 1 hr between\nsummer and winter sleep. Daily variation in\nsleep duration was strongly linked to time of onset,\nrather than offset. None of these groups began sleep\nnear sunset, onset occurring, on average, 3.3 hr after\nsunset. Awakening was usually before sunrise. The\nsleep period consistently occurred during the nighttime\nperiod of falling environmental temperature,\nwas not interrupted by extended periods of waking,\nand terminated, with vasoconstriction, near the nadir\nof daily ambient temperature. The daily cycle of temperature\nchange, largely eliminated from modern\nsleep environments, may be a potent natural regulator\nof sleep. Light exposure was maximal in the\nmorning and greatly decreased at noon, indicating\nthat all three groups seek shade at midday and that\nlight activation of the suprachiasmatic nucleus\nis maximal in the morning. Napping occurred\non \u003c7% of days in winter and \u003c22% of days in summer.\nMimicking aspects of the natural environment\nmight be effective in treating certain modern sleep\ndisorders.","internal_url":"https://www.academia.edu/16877852/Natural_sleep_and_its_seasonal_variants_in_three_pre_industrial_societies","translated_internal_url":"","created_at":"2015-10-16T07:49:40.632-07:00","preview_url":null,"current_user_can_edit":null,"current_user_is_owner":null,"owner_id":5641726,"coauthors_can_edit":true,"document_type":"paper","co_author_tags":[{"id":7367113,"work_id":16877852,"tagging_user_id":5641726,"tagged_user_id":40839284,"co_author_invite_id":1469068,"email":"j***l@ucla.edu","display_order":0,"name":"Jerome Siegel","title":"Natural sleep and its seasonal variants in three pre-industrial societies"},{"id":7367114,"work_id":16877852,"tagging_user_id":5641726,"tagged_user_id":28373658,"co_author_invite_id":null,"email":"h***n@gmail.com","display_order":4194304,"name":"Hillard Kaplan","title":"Natural sleep and its seasonal variants in three pre-industrial societies"},{"id":7367115,"work_id":16877852,"tagging_user_id":5641726,"tagged_user_id":37905717,"co_author_invite_id":128060,"email":"g***n@anth.ucsb.edu","affiliation":"University of California, Santa Barbara","display_order":6291456,"name":"Michael Gurven","title":"Natural sleep and its seasonal variants in three pre-industrial societies"},{"id":7367116,"work_id":16877852,"tagging_user_id":5641726,"tagged_user_id":573491,"co_author_invite_id":null,"email":"b***n@e-flux.com","display_order":7340032,"name":"Brian K Wood","title":"Natural sleep and its seasonal variants in three pre-industrial societies"},{"id":7367117,"work_id":16877852,"tagging_user_id":5641726,"tagged_user_id":104679,"co_author_invite_id":null,"email":"h***r@artsci.wustl.edu","affiliation":"Washington University in St. Louis","display_order":7864320,"name":"Herman Pontzer","title":"Natural sleep and its seasonal variants in three pre-industrial societies"},{"id":7367118,"work_id":16877852,"tagging_user_id":5641726,"tagged_user_id":49633380,"co_author_invite_id":535200,"email":"p***r@wits.ac.za","display_order":8126464,"name":"Paul Manger","title":"Natural sleep and its seasonal variants in three pre-industrial societies"},{"id":7367119,"work_id":16877852,"tagging_user_id":5641726,"tagged_user_id":36419400,"co_author_invite_id":1645709,"email":"c***n@mednet.ucla.edu","display_order":8257536,"name":"Charles Wilson","title":"Natural sleep and its seasonal variants in three pre-industrial societies"},{"id":7367120,"work_id":16877852,"tagging_user_id":5641726,"tagged_user_id":36417770,"co_author_invite_id":1645710,"email":"i***3@gmail.com","display_order":8323072,"name":"ronald mcgregor","title":"Natural sleep and its seasonal variants in three pre-industrial societies"}],"downloadable_attachments":[{"id":39233258,"title":"","file_type":"pdf","scribd_thumbnail_url":"https://attachments.academia-assets.com/39233258/thumbnails/1.jpg","file_name":"15_preindustrial_current_biology.pdf","download_url":"https://www.academia.edu/attachments/39233258/download_file","bulk_download_file_name":"Natural_sleep_and_its_seasonal_variants.pdf","bulk_download_url":"https://d1wqtxts1xzle7.cloudfront.net/39233258/15_preindustrial_current_biology-libre.pdf?1445006645=\u0026response-content-disposition=attachment%3B+filename%3DNatural_sleep_and_its_seasonal_variants.pdf\u0026Expires=1743049091\u0026Signature=GOV6TxvbxbZuWn0MsKzXXx2xsiDHuAlrgtbckMKyICgYaouyze-s7sLVSEll7ixji~8ofFVr43yiAr9DxJG9nPzRsThyOK2HD8-zfSR7y-ypCjbmpGLWy8SLIGwpFLrOxKXv~Z6kz1kKQQHrpvLRFAsPuVAtuf4dD4hpWeVVrDW-vwge-Ivz69vK-pxwXoCTCKtPNndwvKaMKHxw6tglhG~p4dxM3Qb0qy~uFqjqOwiasFrzkse8txG1TQL7xPJUrIoEI5I9fN0jONfzXC2yacGuoRyzbvsQ2x3qJbipHOIj-4oaEJEjwAZZMK2sbxioj1EQuIc9S7yFxritwqufbg__\u0026Key-Pair-Id=APKAJLOHF5GGSLRBV4ZA"}],"slug":"Natural_sleep_and_its_seasonal_variants_in_three_pre_industrial_societies","translated_slug":"","page_count":22,"language":"en","content_type":"Work","summary":"How did humans sleep before the modern era?\nBecause the tools to measure sleep under natural\nconditions were developed long after the invention\nof the electric devices suspected of delaying and\nreducing sleep, we investigated sleep in three preindustrial\nsocieties [1–3]. We find that all three show\nsimilar sleep organization, suggesting that they\nexpress core human sleep patterns, most likely characteristic\nof pre-modern era Homo sapiens. Sleep\nperiods, the times from onset to offset, averaged\n6.9–8.5 hr, with sleep durations of 5.7–7.1 hr,\namounts near the low end of those industrial societies\n[4–7]. There was a difference of nearly 1 hr between\nsummer and winter sleep. Daily variation in\nsleep duration was strongly linked to time of onset,\nrather than offset. None of these groups began sleep\nnear sunset, onset occurring, on average, 3.3 hr after\nsunset. Awakening was usually before sunrise. The\nsleep period consistently occurred during the nighttime\nperiod of falling environmental temperature,\nwas not interrupted by extended periods of waking,\nand terminated, with vasoconstriction, near the nadir\nof daily ambient temperature. The daily cycle of temperature\nchange, largely eliminated from modern\nsleep environments, may be a potent natural regulator\nof sleep. Light exposure was maximal in the\nmorning and greatly decreased at noon, indicating\nthat all three groups seek shade at midday and that\nlight activation of the suprachiasmatic nucleus\nis maximal in the morning. Napping occurred\non \u003c7% of days in winter and \u003c22% of days in summer.\nMimicking aspects of the natural environment\nmight be effective in treating certain modern sleep\ndisorders.","owner":{"id":5641726,"first_name":"Gandhi","middle_initials":null,"last_name":"Yetish","page_name":"GandhiYetish","domain_name":"ucla","created_at":"2013-09-19T08:22:04.517-07:00","display_name":"Gandhi Yetish","url":"https://ucla.academia.edu/GandhiYetish"},"attachments":[{"id":39233258,"title":"","file_type":"pdf","scribd_thumbnail_url":"https://attachments.academia-assets.com/39233258/thumbnails/1.jpg","file_name":"15_preindustrial_current_biology.pdf","download_url":"https://www.academia.edu/attachments/39233258/download_file","bulk_download_file_name":"Natural_sleep_and_its_seasonal_variants.pdf","bulk_download_url":"https://d1wqtxts1xzle7.cloudfront.net/39233258/15_preindustrial_current_biology-libre.pdf?1445006645=\u0026response-content-disposition=attachment%3B+filename%3DNatural_sleep_and_its_seasonal_variants.pdf\u0026Expires=1743049091\u0026Signature=GOV6TxvbxbZuWn0MsKzXXx2xsiDHuAlrgtbckMKyICgYaouyze-s7sLVSEll7ixji~8ofFVr43yiAr9DxJG9nPzRsThyOK2HD8-zfSR7y-ypCjbmpGLWy8SLIGwpFLrOxKXv~Z6kz1kKQQHrpvLRFAsPuVAtuf4dD4hpWeVVrDW-vwge-Ivz69vK-pxwXoCTCKtPNndwvKaMKHxw6tglhG~p4dxM3Qb0qy~uFqjqOwiasFrzkse8txG1TQL7xPJUrIoEI5I9fN0jONfzXC2yacGuoRyzbvsQ2x3qJbipHOIj-4oaEJEjwAZZMK2sbxioj1EQuIc9S7yFxritwqufbg__\u0026Key-Pair-Id=APKAJLOHF5GGSLRBV4ZA"}],"research_interests":[{"id":18594,"name":"Evolutionary Ecology","url":"https://www.academia.edu/Documents/in/Evolutionary_Ecology"},{"id":27315,"name":"Sleep \u0026 Circadian Rhythms","url":"https://www.academia.edu/Documents/in/Sleep_and_Circadian_Rhythms"},{"id":32948,"name":"Hunter-Gatherers (Anthropology)","url":"https://www.academia.edu/Documents/in/Hunter-Gatherers_Anthropology_"},{"id":133324,"name":"Sleep","url":"https://www.academia.edu/Documents/in/Sleep"},{"id":139554,"name":"Accelerometry","url":"https://www.academia.edu/Documents/in/Accelerometry"}],"urls":[]}, dispatcherData: dispatcherData }); 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