Adolescent novelty seeking is associated with greater ventral striatal and prefrontal brain response during evaluation of risk and reward.

Adolescence is a period during which reward sensitivity is heightened. Studies suggest that there are individual differences in adolescent reward-seeking behavior, attributable to a variety of factors, including temperament. This study investigated the neurobiological underpinnings of risk and reward evaluation as they relate to self-reported pleasure derived from novel experiences on the revised Early Adolescent Temperament Questionnaire (EATQ-R). Healthy participants (N = 265, ~50% male), aged 12-17 years, underwent functional magnetic resonance imaging during a modified Wheel of Fortune task, where they evaluated choices with varying probability of winning different monetary rewards. Across all participants, there was increased brain response in salience, reward, and cognitive control circuitry when evaluating choices with larger (compared with moderate) difference in risk/reward. Whole brain and a priori region-of-interest regression analyses revealed that individuals reporting higher novelty seeking had greater activation in bilateral ventral striatum, left middle frontal gyrus, and bilateral posterior cingulate cortex when evaluating the choices for largest difference in risk/reward. These novelty seeking associations with brain response were seen in the absence of temperament-related differences in decision-making behavior. Thus, while heightened novelty seeking in adolescents might be associated with greater neural sensitivity to risk/reward, accompanying increased activation in cognitive control regions might regulate reward-driven risk-taking behavior. More research is needed to determine whether individual differences in brain activation associated with novelty seeking are related to decision making in more ecologically valid settings.

Bottom-up processing of curvilinear visual features is sufficient for animate/inanimate object categorization.

Animate and inanimate objects differ in their intermediate visual features. For instance, animate objects tend to be more curvilinear compared to inanimate objects (e.g., Levin, Takarae, Miner, & Keil, 2001). Recently, it has been demonstrated that these differences in the intermediate visual features of animate and inanimate objects are sufficient for categorization: Human participants viewing synthesized images of animate and inanimate objects that differ largely in the amount of these visual features classify objects as animate/inanimate significantly above chance (Long, Stormer, & Alvarez, 2017). A remaining question, however, is whether the observed categorization is a consequence of top-down cognitive strategies (e.g., rectangular shapes are less likely to be animals) or a consequence of bottom-up processing of their intermediate visual features, per se, in the absence of top-down cognitive strategies. To address this issue, we repeated the classification experiment of Long et al. (2017) but, unlike Long et al. (2017), matched the synthesized images, on average, in the amount of image-based and perceived curvilinear and rectilinear information. Additionally, in our synthesized images, global shape information was not preserved, and the images appeared as texture patterns. These changes prevented participants from using top-down cognitive strategies to perform the task. During the experiment, participants were presented with these synthesized, texture-like animate and inanimate images and, on each trial, were required to classify them as either animate or inanimate with no feedback given. Participants were told that these synthesized images depicted abstract art patterns. We found that participants still classified the synthesized stimuli significantly above chance even though they were unaware of their classification performance. For both object categories, participants depended more on the curvilinear and less on the rectilinear, image-based information present in the stimuli for classification. Surprisingly, the stimuli most consistently classified as animate were the most dangerous animals in our sample of images. We conclude that bottom-up processing of intermediate features present in the visual input is sufficient for animate/inanimate object categorization and that these features may convey information associated with the affective content of the visual stimuli.

Ventral striatal-cingulate resting-state functional connectivity in healthy adolescents relates to later depression symptoms in adulthood.

BACKGROUND: Depression is a significant public health concern. Identifying biopsychosocial risk factors for depression is important for developing targeted prevention. Studies have demonstrated that blunted striatal activation during reward processing is a risk factor for depression; however, few have prospectively examined whether adolescent reward-related resting-state functional connectivity (rsFC) predicts depression symptoms in adulthood and how this relates to known risk factors (e.g., childhood trauma). METHODS: At baseline, 66 adolescents (mean age = 14.7, SD = 1.4, 68 % female) underwent rsFC magnetic resonance imaging and completed the Children's Depression Inventory (CDI). At follow-up (mean time between adolescent scan and adult follow-up = 10.1 years, SD = 1.6, mean adult age = 24.8 years, SD = 1.7), participants completed the Childhood Trauma Questionnaire (CTQ) and Beck Depression Inventory- Second Edition (BDI-2). Average rsFC was calculated between nodes in mesocorticolimbic reward circuitry: ventral striatum (VS), rostral anterior cingulate cortex (rACC), medial orbitofrontal cortex, and ventral tegmental area. Linear regressions assessed associations between rsFC, BDI-2, and CTQ, controlling for adolescent CDI, sex assigned at birth, and scan age (Bonferroni corrected). RESULTS: Greater childhood trauma was associated with higher adulthood depression symptoms. Stronger VS-rACC rsFC during adolescence was associated with greater depression symptoms in adulthood and greater childhood trauma. LIMITATIONS: The small sample size, limited depression severity, and seed-based approach are limitations. CONCLUSIONS: The associations between adolescent striatal-cingulate rsFC and childhood trauma and adult depression symptoms suggest this connectivity may be an early neurobiological risk factor for depression and that early life experience plays an important role. Increased VS-rACC connectivity may represent an over-regulatory response on the striatum, commonly reported in depression, and warrants further investigation.

Adolescent Substance Use Is Associated With Altered Brain Response During Processing of Negative Emotional Stimuli.

OBJECTIVE: Substance misuse is often associated with emotional dysregulation. Understanding the neurobiology of emotional responsivity and regulation as it relates to substance use in adolescence may be beneficial for preventing future use. METHOD: The present study used a community sample, ages 11-21 years old (N = 130, Mage = 17), to investigate the effects of alcohol and marijuana use on emotional reactivity and regulation using an Emotional Go-NoGo task during functional magnetic resonance imaging. The task consisted of three conditions, where target (Go) stimuli were either happy, scared, or calm faces. Self-report lifetime (and past-90-day) drinking and marijuana use days were provided at all visits. RESULTS: Substance use was not differentially related to task performance based on condition. Whole-brain linear mixed-effects analyses (controlling for age and sex) found that more lifetime drinking occasions was associated with greater neural emotional processing (Go trials) in the right middle cingulate cortex during scared versus calm conditions. In addition, more marijuana use occasions were associated with less neural emotional processing during scared versus calm conditions in the right middle cingulate cortex and right middle and inferior frontal gyri. Substance use was not associated with brain activation during inhibition (NoGo trials). CONCLUSIONS: These findings demonstrate that substance use-related alterations in brain circuitry are important for attention allocation and the integration of emotional processing and motor response when viewing negative emotional stimuli.

Heightened adolescent emotional reactivity in the brain is associated with lower future distress tolerance and higher depressive symptoms.

Distress tolerance, the ability to persist while experiencing negative psychological states, is essential for regulating emotions and is a transdiagnostic risk/resiliency trait for multiple psychopathologies. Studying distress tolerance during adolescence, a period when emotion regulation is still developing, may help identify early risk and/or protective factors. This study included 40 participants (mean scan age = 17.5 years) and using an emotional Go-NoGo functional magnetic resonance imaging task and voxel-wise regression analysis, examined the association between brain response during emotional face processing and future distress tolerance (two ± 0.5 years), controlling for sex assigned at birth, age, and time between visits. Post-hoc analyses tested the mediating role of distress tolerance on the emotional reactivity and depressive symptom relationship. Whole-brain analysis showed greater inferior occipital gyrus activation was associated with less distress tolerance at follow-up. The mediating role of distress tolerance demonstrated a trend-level indirect effect. Findings suggest that individuals who allocate greater visual resources to emotionally salient information tend to exhibit greater challenges in tolerating distress. Distress tolerance may help to link emotional reactivity neurobiology to future depressive symptoms. Building distress tolerance through emotion regulation strategies may be an appropriate strategy for decreasing depressive symptoms.