Poster A39, Saturday, March 24, 1:30–3:30 pm, Exhibit Hall C
IMAGING STRESS EFFECTS ON WORKING MEMORY CAPACITY IN ADOLESCENTS AT-RISK
Ashley Williams1,2, Jessica Graham1,2, Candace Killian-Farrell1, Josh Bizzell1, Hannah Waltz1, Erin King3, Alana Campbell1, Aysenil Belger1,2; 1University of North Carolina at Chapel Hill, Department of Psychiatry, 2Duke University-UNC Brain and Imaging Analysis Center, 3Emory University
Psychosocial stress has been identified as a key trigger for numerous neuropsychiatric disorders, many of which emerge in adolescence. The late maturation of prefrontal neural networks that regulate the stress response creates a unique target for stress-induced modulation of adolescent brain and cognition. The present study examined the impact of acute stress on neural networks responsible for working memory (WM) in adolescents at risk for complex neuropsychiatric disorders. We hypothesized that as WM load increased, participants would have difficulty recruiting frontal areas to support successful WM. Fifty-four adolescent participants (aged 9-16 years) were imaged during a 0-, 1-, and 2-back before and after an imaging stress task (MIST). Results revealed (1) Stress effects: a significant (p<.01 corrected) reduction in prefrontal activation during WM post-stress, coupled with a significant (p<.01) increase in posterior occipital activation. (2) Load effects: prefrontal region activation was smaller in the 2-back relative to 1-back condition post-stress. (3) Group effects: adolescents at high-risk (ADHD/ANXIETY/or familial-high risk) showed significantly more sensitivity to this stress effect (p<.01), such that low-risk adolescents preserved frontal activation, while those at high-risk rely on sensory areas after stress. (4) Sex effects: Females only showed prefrontal suppression and increased sensory and limbic activation as working memory load increased. These results suggest that patterns of stress response and recovery may procure unique vulnerabilities to cognitive domains, highlighting the importance of controlling or modeling these effects when investigating individual differences in brain and cognition in adolescents.
Topic Area: EXECUTIVE PROCESSES: Working memory