Research demonstrates a negative impact of sleep disturbance on mood and affect; however, the biological mechanisms mediating these links are poorly understood. Amygdala reactivity to negative stimuli has emerged as one potential pathway. Here, we investigate the influence of self-reported sleep quality on associations between threat-related amygdala reactivity and measures of negative affect and perceived stress.
Analyses on data from 299 participants (125 men, 50.5% white, mean [standard deviation] age = 19.6 [1.3] years) who completed the Duke Neurogenetics Study were conducted. Participants completed several self-report measures of negative affect and perceived stress. Threat-related (i.e., angry and fearful facial expressions) amygdala reactivity was assayed using blood oxygen level–dependent functional magnetic resonance imaging. Global sleep quality was assessed using the Pittsburgh Sleep Quality Index.
Amygdala reactivity to fearful facial expressions predicted greater depressive symptoms and higher perceived stress in poor (β values = 0.18–1.86, p values < .05) but not good sleepers (β values = −0.13 to −0.01, p values > .05). In sex-specific analyses, men reporting poorer global sleep quality showed a significant association between amygdala reactivity and levels of depression and perceived stress (β values = 0.29–0.44, p values < .05). In contrast, no significant associations were observed in men reporting good global sleep quality or in women, irrespective of sleep quality.
This study provides novel evidence that self-reported sleep quality moderates the relationships between amygdala reactivity, negative affect, and perceived stress, particularly among men.
From the Department of Psychiatry (A.A.P.) and The Robert Wood Johnson Foundation Health and Society Scholars Program (A.A.P.), University of California, San Francisco, and University of California, Berkeley, California; BRAIN Lab, Department of Psychology (R.B.), Washington University in St. Louis, St. Louis, Missouri; and Laboratory of NeuroGenetics, Department of Psychology and Neuroscience, Institute for Genome Sciences and Policy (R.B., A.R.H.), Duke University, Durham, North Carolina.
Address correspondence and reprint requests to Aric A. Prather, PhD, Center for Health and Community, University of California, San Francisco, 3333 California St., Suite 465, San Francisco, CA 94118. E-mail: firstname.lastname@example.org
A podcast discussion of this article is available online with this issue.
Received for publication August 20, 2012; revision received December 10, 2012.