Delayed Sleep Timing in Teens Study

Study Overview
=================
Brief Summary
-----------------
This study will (1) comprehensively characterize the substance use disorder (SUD) risk profile associated with adolescent Delayed Sleep Phase (DSP), and (2) probe whether SUD risk is diminished by altering sleep/circadian timing.

Detailed Description
-----------------
Mounting evidence indicates that delayed sleep phase (DSP) may confer risk for adolescent substance use (SU) and SUDs. However, the exact nature of this link and the mechanisms underlying it remain unclear. Circadian misalignment, a mismatch between late sleep hours and early school start times, is a compelling potential contributor to elevated SU in adolescent DSP with plausible neurobehavioral mechanisms. The investigators hypothesize that DSP-associated circadian misalignment decreases impulse control and increases reward sensitivity, thereby increasing SUD risk. This study will, for the first time, (1) comprehensively characterize the SUD risk profile associated with adolescent DSP, and (2) probe whether SUD risk is diminished by altering sleep/circadian timing. The study will assess both established markers of SUD risk and putative neurobehavioral mechanisms (impulsivity and reward sensitivity). Specifically, the investigators will employ a comprehensive, multi-method approach to examining DSP's role in SUD risk, combining laboratory, experimental, and longitudinal studies. The investigators will recruit a sample of 150 eleventh and twelfth graders (16-19 y/o), divided between 100 DSP and 50 normal phase teens. The investigators will focus on cannabis and alcohol use given their prevalent use in adolescents and evident links to DSP. In the experimental study, the investigators will probe whether stabilizing circadian phase in the DSP group (n=100) by using sleep scheduling and chronotherapeutic approaches (i.e., dim light in the evening and bright light in the morning) improves sleep and neurobehavioral function relevant to SUD risk.

Official Title
-----------------
Delayed Sleep Phase and Risk for Adolescent Substance Use

Conditions
-----------------
Delayed Sleep Phase

Intervention / Treatment
-----------------
* Other: Increase morning bright light
* Other: Decrease evening blue light
* Behavioral: Sleep scheduling
* Behavioral: Monitor sleep, mood, and substance use


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Age 16-19 years Currently in 11th or 12th grade and enrolled in a traditional high-school; or cyber school with synchronous classes (not home-schooled) Physically and psychiatrically healthy, as determined by instruments described below Provision of written informed consent and assent Additional inclusion criterion for Experimental protocol Meets operational definition of delayed sleep phase (DSP; weekend bedtime ≥1 AM) Exclusion Criteria: Significant or unstable acute or chronic medical conditions Past or current bipolar disorder or psychotic disorder Past or current substance use disorder other than alcohol use disorder or cannabis use disorder Past month recreational drug use other than alcohol, cannabis, and nicotine Current syndromal sleep disorders other than insomnia and delayed sleep phase disorder Medications that interfere with sleep and/or reward function (antidepressants, and stimulants prescribed for ADHD are permitted) Conditions that would interfere with the MRI procedures (e.g., non-removal ferromagnetic devices)

Ages Eligible for Study
-----------------
Minimum Age: 16 Years
Maximum Age: 19 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Manipulation<br>For  2 weeks, participants will be asked to adhere to the following: Sleep scheduling--advance bedtime by 1.5 hours ( + sleep duration) Decrease evening blue light exposure via blue blocker goggles (2 h before bed) Increase morning bright light exposure via bright light goggles (30 m after rise) Monitor sleep, mood, and substance use via smartphone-based platform and wrist actigraph | Other: Increase morning bright light<br>* Participants will wear Re-Timer bright glasses for 30 minutes each morning<br>Other: Decrease evening blue light<br>* Participants will wear tinted glasses that block blue wavelength light for 2 hours before bed<br>Behavioral: Sleep scheduling<br>* Participants will advance their weekday bedtime and maintain their weekday risetime on weekends<br>Behavioral: Monitor sleep, mood, and substance use<br>* Participants will monitor sleep, mood, and substance use via smartphone-based platform and wrist actigraphy<br>|
| Active Comparator: Control<br>For  2 weeks, participants will asked to adhere to the following: - Monitor sleep, mood, and substance use via smartphone-based platform and wrist actigraph | Behavioral: Monitor sleep, mood, and substance use<br>* Participants will monitor sleep, mood, and substance use via smartphone-based platform and wrist actigraphy<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Circadian alignment | Interval between dim light melatonin onset and midsleep | Post-manipulation (comparing assessment after  2-week sleep manipulation to the assessment at baseline) | 
| Behavioral inhibition | Accuracy on Cued Go/No-Go Task, specifically correct response (withholding response) on go trials with no/go target | Post-manipulation (comparing assessment after  2-week sleep manipulation to the assessment at baseline) | 
| Reward motivation (behavioral) | Adjusted average pumps on Balloon Analogue Risk Task, a computerized measure of risk taking behavior in participants are presented with a series of balloons and offered the chance to earn money by pumping each balloon up by clicking a button. | Post-manipulation (comparing assessment after  2-week sleep manipulation to the assessment at baseline) | 
| Neural correlates of impulse control | Activation within the Executive Control Network during the Stop Signal Task. Specifically, activation is defined as bold signal in regions of the Executive Control Network (particularly the inferior frontal gyrus) on correct Stop trials versus correct Go trials. | Post-manipulation (comparing assessment after  2-week sleep manipulation to the assessment at baseline) | 
| Neural correlates of reward anticipation | Activation within the reward network during the Monetary Incentive Delay task. Specifically, activation is defined as bold signals in regions of the reward network (particularly the ventral striatum) on reward anticipation trials versus no money trials. | Post-manipulation (comparing assessment after  2-week sleep manipulation to the assessment at baseline) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cannabis use | Cannabis use on Time Line Follow Back interview. Specifically, the frequency (# of days) of cannabis use (yes/no) in the past 2 months. | During follow-ups after the manipulation through study completion, up to 5 years | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
sleep, circadian, adolescence, substance use, reward, impulse control