An interventional study of Sleep Pressure Manipulation in Suicidal Ideation, Circadian Rhythm Disorders and Sleep Deprivation, sponsored by University of Arizona. Recruiting at 1 site in United States. Open to participants aged 18 Years to 55 Years. Per ClinicalTrials.gov, last updated 2026-10-01.
Sponsored by University of Arizona · Not applicable, Interventional, and Basic science
This study examines whether wakefulness during the biological night (2:00-4:00 AM) is associated with increased negative mood, impaired decision-making, and suicidal thoughts. Adults with a history of suicidal ideation in the past six months will complete laboratory and home-based assessments under varying levels of sleep pressure. Participants will be evaluated during late-night wakefulness and under conditions of both higher and lower sleep pressure. The goal of the study is to better understand the biological and behavioral mechanisms that may contribute to elevated suicide risk during nocturnal wakefulness.
Suicide risk is elevated during the biological night, particularly between 2:00 and 4:00 AM. Observational and epidemiologic data suggest that nocturnal wakefulness is associated with increased negative affect, impaired decision-making, and greater suicidal ideation. The "Mind After Midnight" hypothesis proposes that wakefulness during the biological night exposes individuals to a combination of circadian vulnerability and homeostatic sleep pressure that contributes to emotional and cognitive dysregulation.
This study will recruit approximately 90 adults with a history of suicidal ideation in the past six months. Participants will complete both home-based and laboratory-based procedures. Laboratory assessments will evaluate mood, hopelessness, suicidal ideation, impulsivity, and decision-making at different times of day, including 2:00-4:00 AM. To examine the role of homeostatic sleep pressure, participants will complete late-night assessments under two conditions: (1) high sleep pressure (remaining awake until 2:00 AM) and (2) low sleep pressure (sleeping and being awakened at 2:00 AM). Circadian factors will be assessed using behavioral measures and physiologic markers, including melatonin.
The goal of the study is to experimentally test whether nocturnal wakefulness contributes to suicide-associated cognitive and affective processes and to identify underlying chronobiological mechanisms.
569 studies on the registry are indexed under Suicidal Ideation; 203 are open to participants now.
This study's planned enrollment of 90 is above the median of 80 across 469 interventional studies indexed under Suicidal Ideation.
Browse Suicidal Ideation studies →University of Arizona is the lead sponsor of 476 studies on the registry; 88 are open to participants now.
Of its 51 completed or terminated interventional studies of FDA-regulated products, 30 (59%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will remain awake until 2:00 AM to induce high homeostatic sleep pressure. During the biological night (2:00-4:00 AM), participants will complete assessments of mood, suicidal ideation, impulsivity, and decision-making under conditions of sustained wakefulness.
Behavioral: Sleep Pressure Manipulation
Participants will be allowed to sleep and will be awakened at 2:00 AM to induce lower homeostatic sleep pressure. During the biological night (2:00-4:00 AM), participants will complete assessments of mood, suicidal ideation, impulsivity, and decision-making following sleep and acute awakening.
Behavioral: Sleep Pressure Manipulation
Participants undergo an experimental manipulation of homeostatic sleep pressure involving controlled wakefulness or scheduled awakening during the biological night. Mood, suicidal ideation, impulsivity, and decision-making are assessed during overnight laboratory sessions.
Feelings of Hopelessness
Total score on the BECK Hopelessness scale (BHS)
Time frame: Visit 1(day 2, night 2), Visit 2 (day 2, night 2)
Impaired Executive Function
BART total score
Time frame: Visit 1(day 2, night 2), Visit 2 (day 2, night 2)
Negative Mood
PANAS negative affect score
Time frame: Visit 1(day 2, night 2), Visit 2 (day 2, night 2)
Plan to share: No
No publications or documents are linked to this record.
Started Mar 2026 (actual). Primary completion is estimated for Feb 2029, 35 months after the start.
Of 281 non-industry interventional studies with no phase under Suicidal Ideation, half reached primary completion within 30 months of starting (the median), counting those still running; a quarter within 13 and three quarters within 54. This study's planned 35 months is above that.
Counting every sponsor, half of 290 studies reached it within 29 months; a quarter within 13 and three quarters within 53.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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