Poster #189 - Sleep-Related Neural Activation is Associated with Threat Detection in Adolescents

• In Event: 3-159 - Poster Session 12
  In Poster Session: PS 12 Section - Social Cognition

Integrative Statement

Adolescence is characterized by significant biological, neural, and social changes. Biologically, adolescence undergo puberty which has influences on the regulation of their circadian system resulting in insufficient sleep durations (Carskadon, 2011). Concurrently, adolescents experience neural maturation important for a variety of cognitive abilities, including face perception (Golarai et al., 2009). This development is particularly relevant as adolescents expand their social milieu, which requires attending to the environment in order to make inferences about unknown social counterparts (Kilford et al., 2016). Little is known about the way these systems integrate to affect adolescent behavior. In this study, we investigated whether sleep duration related to neural activation during a face evaluation task and subsequently, how individual differences in activation were associated with task performance.

Forty healthy adolescents ages 14-18 years old (22 female, Mage =15.950 years, SD =1.061) participated in the study. For 14 days, participants wore an actigraphy watch to track objective indices of sleep. At the end of the two-week period, participants performed a threat discrimination task while undergoing functional magnetic resonance imaging (fMRI). During the task, participants evaluated a series of computer-generated faces that morphed along a pre-established threat continuum (1=not threatening to 7=threatening) (Figure 1) (Oosterhof & Todorov, 2008). Participants rated each face as either “threatening” or “not threatening” (binary responses, 1 and 0 respectively). Behavioral data for the task were analyzed using a multi-level modeling framework because our data consisted of repeated measures (trials) nested within individuals.

On average, participants attained 433.433 minutes (7.224 hours) of sleep per night (SD=59.463). Whole brain analyses revealed sleep duration was associated with neural activation during the faces task for the contrast of face judgments versus baseline, cluster-forming threshold Z>2.3, extent threshold p<.05, familywise error corrected. Adolescents with longer average sleep durations evinced greater activation in the left fusiform face area (FFA) and occipital cortex, regions associated with face processing abilities. This activation was significantly associated with face ratings such that adolescents with greater activation rated more faces as threatening than not threatening during the task (estimate=.008, SE=.004, z=2.364, p=.018) (Figure 2). Valence rankings (1 to 7 on the pre-established threat continuum) were also significantly associated with judgments such that participants rated a greater number of faces as threatening at the higher end of the continuum compared to faces at the lower end of the continuum (estimate=.515, SE=.072, z=7.203, p<.001).

Our results demonstrated adolescents who attained more sleep showed greater neural activation in key face processing regions when evaluating faces during the threat discrimination task. Greater activation was associated with more sensitivity to judge faces as threatening across the task (e.g., a higher proportion of faces rated as threatening). Findings held controlling for age, sex, and objective face valence, which was highly related to threat ratings (activation estimate from covariate model=.007, SE=.004, z=2.126, p=.034). Adolescence is characterized by biological and psychosocial changes that may affect neural and behavioral functioning. Our results demonstrate sleep is important for optimal neural functioning that facilitates attending to an increasingly complex social environment.

Authors

• Sarah Marie Tashjian, University of California, Los Angeles
  Presenting Author

• Adriana Galván, University of California, Los Angeles
  Non-Presenting Author