Associations Between Sleep Health, Negative Reinforcement Learning,and Alcohol Use in College Students with Elevated Internalizing Symptoms

Background

Negative reinforcement has been proposed to mediate associations between sleep and alcohol use, especially among people with internalizing symptoms (depression, anxiety). Worse sleep (shorter duration, less efficiency, more irregular timing) exacerbates negative emotions, which alcohol may temporarily relieve. Not yet examined, we propose differences in how individuals learn from negative reinforcement may mediate associations between sleep and alcohol use, since sleep impacts emotion, reward response, and learning.

The current study aimed to replicate associations between sleep and alcohol use; test whether each was associated with negative reinforcement learning (NRL); and test whether NRL mediates associations between sleep health and alcohol use. If so, worse sleep may predict greater likelihood of using alcohol to relieve negative emotions, increasing risk for alcohol use disorder.

Methods

Seventy-five college students varying in internalizing symptoms (ages 18-20 years, n = 58 female) wore Fitbit smartwatches and completed daily diaries measuring sleep and substance use for ~14 days before completing two computer tasks where they learned which of two options (Left/Right) had a greater chance of negative stimulus removal. The three pathways comprising the proposed mediational model were separately tested via robust generalized linear models.

Results

Sleep timing variability was positively associated with alcohol use, but neither were associated with NRL. Post-hoc exploratory models examining moderation by anxiety and depression indicated positive associations between sleep timing variability and alcohol use were weaker at higher levels of anxiety severity and stronger at high levels of depression symptom severity.

Conclusions

Sleep timing variability is associated with alcohol use, unrelated to NRL. This association is weaker at high levels of anxiety and stronger at high levels of depression. Future research is needed to replicate findings, confirm causality of observed interactions, and examine sleep regularity as a target for improving alcohol-related outcomes among college students with depressive symptoms.

Major Professors: Dr. Dana McMakin and Dr. Aaron Mattfeld