Individual differences in accumbofrontal tract integrity relate to risky decisions under stress in adolescents and adults

Abstract

Psychosocial stress increases risky decision-making (DM). It is widely accepted that individual variation in neural phenotypes underlie variability in this behavioral tendency in adults, but is less examined in adolescents. Our goal was to test the hypothesis that the relation between neural phenotypes and stress-related risky DM is better characterized by individual variation than by age. Using diffusion tensor imaging (DTI) tractography to characterize the accumbofrontal tract, we determined if it uniquely moderated how stress affects risky DM, over and above age. A daily diary design monitored participants’ daily stress for two weeks. Participants completed a DTI scan and performed a task in which decisions varied by expected value, once each on a day when they endorsed feeling higher (and lower) than usual levels of stress. Multilevel logistic regression analyses revealed that all participants were more likely to take risks as expected reward value increased; this behavior was greater under high versus low stress for individuals with low accumbofrontal tract integrity, whereas DM was less influenced by stress for individuals with high accumbofrontal tract integrity, regardless of age. Results suggest that individual differences in brain structure may be more germane to characterizing risky decisions in adolescents, rather than ontogeny.

Adolescent decision making: A decade in review

“…It is also notable that not all teens engage in problematic risk taking. Such behavioral differences likely stem from individual differences in the underlying drivers of risk taking including psychological and neurobiological factors (e.g., Uy & Galvan, 2020), in addition to differences in opportunity. As Khurana et al.…”

Adolescent Brain Development and Contextual Influences: A Decade in Review

“…They found that neural connectivity exhibited less mature brain states under high‐emotions states, which was associated with greater risk preference in adolescents and young adults (Rudolph et al., 2017). In a study examining risk‐taking under self‐reported high‐stress conditions (as indexed with daily diary), multilevel logistic regression analyses revealed that although all participants were more likely to take risks as expected reward value increased, this behavior was greater under high versus low stress for individuals with low accumbofrontal tract integrity (i.e., less connectivity between the ventral striatum and frontal cortex; Uy & Galván, 2010). Results suggest that individual differences in brain structure and function are just as germane to characterizing risky decisions in adolescents as ontogeny.…”

Integrating dynamic interactionism into the brain–stress–psychopathology relationship.

“…Amygdala reactivity to or functional connectivity with other brain regions while viewing negative stimuli, assessed either prior to a traumatic event or shortly therafter, prospectively predicts the onset of PTSD symptoms (e.g., Belleau et al, 2020;Fani et al, 2019;Lin et al, 2017; Stevens et al, 2017). van Rooij et al (2018) also demonstrated that blunted hippocampal responses to a response inhibition task within 24 hr of a traumatic event predicted worsened PTSD symptoms one month later. Some EEG research has similarly found that neural responses to reappraisals of negative emotions predict symptom reductions 1 year later in those with PTSD (Fitzgerald et al, 2018).…”

“…For men with low amygdala reactivity, however, socioeconomic resources at age 20 did not predict later antisocial behavior. In a recent experimental DTI study (Uy & Galván, 2020), in which participants had to make decisions that varied in terms of risk and reward, high accumbofrontal tract integrity moderated effects of daily levels of stress on decision making, such that elevated stress was linked to increased risk taking, but only if accumbofrontal integrity was low.…”