Mechanisms of Risky Alcohol Use in Young Adults: Linking Sleep Duration and Timing to Reward- and Stress-Related Brain Function

This research will use biobehavioral approaches to generate understanding about the linkages between stressful life events, sleep duration and timing, and alcohol use in young adults, with a long-term aim of developing effective preventative interventions for alcohol use disorders.

Inclusion Criteria:18-24 years of age;NIAAA criteria for past-month high-risk drinking (i.e., ≥ 4 drinks/day or ≥ 8/week for women, ≥ 5 drinks/day or ≥ 15/week for men);short and late sleep (weekday sleep duration ≤ 6 h & midpoint ≥ 4 am; n=60) or long and early sleep (weekday sleep duration ≥ 8h & midpoint ≤2:30 am; n=30), which will be determined with the Munich Chronotype Questionnaire;at least moderate lifetime exposure to stressors (>6 events on the 20-item Adult Stress and Adversity Inventory-Screener);not currently in high school; andEnglish language fluency.Exclusion Criteria:Severe alcohol use disorder (AUD) and/or substance use disorder (SUD), defined as ≥6 AUD/SUD criteria in the Diagnostic and Statistical Manual-5;acute alcohol intoxication on the days of the laboratory post-intensive visits, operationalized as a blood alcohol concentration of .02 or higher during Breathalyzer saliva screen;current sleep disorders other than insomnia and delayed sleep phase disorder;lifetime diagnosis of bipolar or schizophrenia spectrum disorder;moderate to high suicide risk;certain medical conditions (e.g., neurological disorder, heart failure or trouble, high blood pressure, history of head injury with unconsciousness > 5 minutes);conditions that are contraindicated for MRI (e.g., ferrous metal in the body);positive screen for participant-reported eye disease, epilepsy, or photosensitizing medications that are contraindicated during the manipulation condition when bright light is administered (e.g., psychiatric neuroleptic drugs [e.g., phenothiazine], psoralen drugs, antiarrhythmic drugs [e.g., amiodarone], antimalarial and antirheumatic drugs, porphyrin drugs used in photodynamic treatment of skin diseases);travel across two or more time zones within the month prior to the overnight study visits.begin/end a prescribed medication within 2 months of the observational study;medication dose changes within the timeframe calculated as 5x the drug's half-life [the time to reach pharmacokinetic steady-state] before the initiation of the observational or experimental studies;participant-anticipated changes in prescribed medications or medication dosing during the observational or experimental studies;self-reported use of opioids, benzodiazepines, hallucinogens, or stimulants (other than caffeine and nicotine) within 24 hours of study visits;self-reported symptoms of withdrawal from depressants or stimulants on days of study visits; anduse of melatonin if participant is not willing to discontinue use for the duration of the study.