This study aims to to test effects of sleep loss on perceived discrimination and cardiovascular functioning as well as identify moderators of the racial discrimination and objective sleep link in a sample of 80 African Americans.

African Americans (AAs) are disproportionately burdened by clinical and subclinical cardiovascular disease (CVD) when compared to European Americans (EAs), and while experiences of racial discrimination have been associated with CVD morbidity among AAs, including high daytime and nighttime blood pressure, the mechanisms underlying these associations are unclear. Poor sleep, such as short sleep duration and poor sleep continuity, may serve as a novel pathway; however, this possibility has not been rigorously tested. Evidence linking racial discrimination and poor sleep is mounting, however, largely derived from cross-sectional studies. Further, researchers have largely ignored the possibility of reciprocal effects. In a separate study (CHR#:18-24889) the investigators are testing the effects of perceived discrimination on sleep and nocturnal physiology. In this study, however, the investigators aim to test whether the other direction- whether experimental sleep loss affects one's perception and reaction to social interaction tasks with an outgroup member (White participant). To this end, the investigators will randomize 80 healthy AAs to one night of total sleep restriction or normal sleep in the sleep laboratory and then expose them to several standardized social experience tasks. These tasks include a digit span task, social evaluative speech task and cooperative task (i.e., playing Taboo), all of which will occur in the context of subtle negative evaluative feedback from the White confederate. Cardiovascular functioning as well as self-reported affect will be measured throughout the tasks and potential moderators, including socioeconomic status and race-based rejection sensitivity, will be tested. This study will fill fundamental gap in the scientific literature and provide the critical causal and mechanistic evidence necessary to address racial disparities in sleep and cardiovascular risk.

Inclusion Criteria:

• Age: 18 to old 64 years old
• Self-identified African American/Black
• English speaking, able to provide informed consent
• Self-reported bedtime between 10 PM and 12 AM for 5/7 nights for the past 3-months (stability to be confirmed by actigraphy and sleep diary)
• Self-reported sleep duration of between 6.5 and 8.5 hours for 5/7 nights for the last month (duration to be confirmed by actigraphy and sleep diary)

Exclusion Criteria:

• Aged greater than 64 years (to minimize age-related differences in sleep quantity and architecture).
• Body mass index of 40 or above (to exclude for obesity, which can impair physiologic recording and confound study outcomes).
• Presence of any clinical sleep disorder, including insomnia and obstructive sleep apnea (OSA), as assessed by validated screening measure. OSA will also be assessed objectively during the Sleep Screening period.
• Medical or psychiatric condition, as assessed by self-report and clinical interview, that is likely to affect sleep/wake function or cardiovascular functioning, including doctor diagnosed arrhythmia, hypertension, congestive heart failure, major depression, bipolar disorder, post-traumatic stress disorder.
• Medication use that is likely to affect sleep/wake function or cardiovascular functioning, including antidepressants, anxiolytic or soporific medication, and beta-blockers.

Our plan is to make all processed data available at the conclusion of the study in line with NIH guidelines.

All processed data should be available within 5 years of completion of the study

Consistent with NIH guidelines

Participants will be blind to their condition up until right before they begin their night of normal sleep or total restriction. Participants will also be blind to the nature of the social-rejection task until the debriefing.