Aaron S. Heller

When Is an Adolescent an Adult? Assessing Cognitive Control in Emotional and Nonemotional Contexts

An individual is typically considered an adult at age 18, although the age of adulthood varies for different legal and social policies. A key question is how cognitive capacities relevant to these policies change with development. The current study used an emotional go/no-go paradigm and functional neuroimaging to assess cognitive control under sustained states of negative and positive arousal in a community sample of one hundred ten 13- to 25-year-olds from New York City and Los Angeles. The results showed diminished cognitive performance under brief and prolonged negative emotional arousal in 18- to 21-year-olds relative to adults over 21. This reduction in performance was paralleled by decreased activity in fronto-parietal circuitry, implicated in cognitive control, and increased sustained activity in the ventromedial prefrontal cortex, involved in emotional processes. The findings suggest a developmental shift in cognitive capacity in emotional situations that coincides with dynamic changes in prefrontal circuitry. These findings may inform age-related social policies.

Neural Mechanisms of Emotion Regulation in Autism Spectrum Disorder

Autism spectrum disorder (ASD) is characterized by high rates of comorbid internalizing and externalizing disorders. One mechanistic account of these comorbidities is that ASD is characterized by impaired emotion regulation (ER) that results in deficits modulating emotional responses. We assessed neural activation during cognitive reappraisal of faces in high functioning adults with ASD. Groups did not differ in looking time, pupilometry, or subjective ratings of faces during reappraisal. However, instructions to increase positive and negative emotional responses resulted in less increase in nucleus accumbens and amygdala activations (respectively) in the ASD group, and both regulation instructions resulted in less change in dorsolateral prefrontal cortex activation in the ASD group. Results suggest a potential mechanistic account of impaired ER in ASD.

The neurodynamics of emotion: delineating typical and atypical emotional processes during adolescence

The study of development is, in and of itself, the study of change over time, but emotions, particularly emotional reactivity and emotional regulation, also unfold over time, albeit over briefer time-scales. Adolescence is a period of development characterized by marked changes in emotional processes and rewiring of the underlying neural circuitry, making this time of life formative. Yet this period is also a time of increased risk for anxiety and mood disorders. Changes in the temporal dynamics of emotional processes (e.g. magnitude, time-to-peak and duration) occur during this developmental period and have been associated with risk for mood and anxiety disorders. In this article, we describe how the temporal dynamics of emotions change during adolescence and how they may increase risk for these psychopathologies. We highlight studies that illustrate how formalizing temporal neurodynamics of emotion may enhance links among levels of analyses from neurobiological to real-world, moment-to-moment experiences.

Purposeful Engagement, Healthy Aging, and the Brain

Purpose of ReviewResearch on psychological well-being in later life has identified strengths and vulnerabilities that occur with aging. We review the conceptual and philosophical foundations of a eudaimonic model of well-being and its empirical translation into six key dimensions of positive functioning. We also consider its implications for health, broadly defined.Recent FindingsNumerous findings from national longitudinal samples of US adults are described. They show declining scores on purpose in life and personal growth with aging, but also underscore the notable variability among older persons in these patterns. Recently, health benefits have been identified among older adults who maintain high levels of a particular aspect of well-being, namely, purposeful life engagement. These benefits include extended longevity, reduced risk for various disease outcomes, reduced physiological dysregulation, and gene expression linked to better inflammatory profiles. The brain mechanisms that underlie such outcomes are also examined via a focus on affective style. Adults with higher levels of purpose in life show more rapid recovery from negative stimulus provocation, whereas those with higher well-being overall show sustained activation of reward circuitry in response to positive stimuli, and this pattern is associated with lower diurnal cortisol output. Volumetric findings (right insular gray matter volume) have also been linked with eudaimonic well-being.SummaryEudaimonic well-being predicts better health and longer lives, and thus constitutes an important direction for future research and practice. Intervention studies designed to promote well-being, including among those suffering from psychological disorders, are briefly described.

Cortical-Subcortical Interactions in Depression: From Animal Models to Human Psychopathology

Depression is a debilitating disorder causing significant societal and personal suffering. Improvements in identification of major depressive disorder (MDD) and its treatment are essential to reduce its toll. Recent developments in rodent models of MDD and neuroimaging of humans suffering from the disorder provide avenues through which gains can be made towards reducing its burden. In this review, new findings, integrating across rodent models and human imaging are highlighted that have yielded new insights towards a basic understanding of the disorder. In particular, this review focuses on cortical-subcortical interactions underlying the pathophysiology of MDD. In particular, evidence is accruing that dysfunction in prefrontal-subcortical circuits including the amygdala, ventral striatum (VS), hippocampus and dorsal raphe nucleus (DRN) are associated with MDD status.

Moment-to-moment BOLD signal variability reflects regional changes in neural flexibility across the lifespan

Variability of neuronal responses is thought to underlie flexible and optimal brain function. Because previous work investigating BOLD signal variability has been conducted within task-based fMRI contexts on adults and older individuals, very little is currently known regarding regional changes in spontaneous BOLD signal variability in the human brain across the lifespan. The current study used resting-state fMRI data from a large sample of male and female human participants covering a wide age range (6–85 years) across two different fMRI acquisition parameters (TR = 0.645 and 1.4 s). Variability in brain regions including a key node of the salience network (anterior insula) increased linearly across the lifespan across datasets. In contrast, variability in most other large-scale networks decreased linearly over the lifespan. These results demonstrate unique lifespan trajectories of BOLD variability related to specific regions of the brain and add to a growing literature demonstrating the importance of identifying normative trajectories of functional brain maturation. SIGNIFICANCE STATEMENT Although brain signal variability has traditionally been considered a source of unwanted noise, recent work demonstrates that variability in brain signals during task performance is related to brain maturation in old age as well as individual differences in behavioral performance. The current results demonstrate that intrinsic fluctuations in resting-state variability exhibit unique maturation trajectories in specific brain regions and systems, particularly those supporting salience detection. These results have implications for investigations of brain development and aging, as well as interpretations of brain function underlying behavioral changes across the lifespan.

The impact of emotional states on cognitive control circuitry and function

Typically in the laboratory, cognitive and emotional processes are studied separately or as a stream of fleeting emotional stimuli embedded within a cognitive task. Yet in life, thoughts and actions often occur in more lasting emotional states of arousal. The current study examines the impact of emotions on actions using a novel behavioral paradigm and functional neuroimaging to assess cognitive control under sustained states of threat (anticipation of an aversive noise) and excitement (anticipation of winning money). Thirty-eight healthy adult participants were scanned while performing an emotional go/no-go task with positive (happy faces), negative (fearful faces), and neutral (calm faces) emotional cues, under threat or excitement. Cognitive control performance was enhanced during the excited state relative to a nonarousing control condition. This enhanced performance was paralleled by heightened activity of frontoparietal and frontostriatal circuitry. In contrast, under persistent threat, cognitive control was diminished when the valence of the emotional cue conflicted with the emotional state. Successful task performance in this conflicting emotional condition was associated with increased activity in the posterior cingulate cortex, a default mode network region implicated in complex processes such as processing emotions in the context of self and monitoring performance. This region showed positive coupling with frontoparietal circuitry implicated in cognitive control, providing support for a role of the posterior cingulate cortex in mobilizing cognitive resources to improve performance. These findings suggest that emotional states of arousal differentially modulate cognitive control and point to the potential utility of this paradigm for understanding effects of situational and pathological states of arousal on behavior.

Development of the emotional brain

In this article, we highlight the importance of dynamic reorganization of neural circuitry during adolescence, as it relates to the development of emotion reactivity and regulation. We offer a neurobiological account of hierarchical, circuit-based changes that coincide with emotional development during this time. Recent imaging studies suggest that the development of the emotional brain involves a cascade of changes in limbic and cognitive control circuitry. These changes are particularly pronounced during adolescence, when the demand for self regulation across a variety of emotional and social situations may be greatest. We propose that hierarchical changes in circuitry, from subcortico-subcortical to subcortico-cortical to cortico-subcortical and finally to cortico-cortical, may underlie the gradual changes in emotion reactivity and regulation throughout adolescence into young adulthood, with changes at each level being necessary for the instantiation of changes at the next level.

Resting-state brain signal variability in prefrontal cortex is associated with ADHD symptom severity in children

Atypical brain function in attention-deficit/hyperactivity disorder (ADHD) has been identified using both task-activation and functional connectivity fMRI approaches. Recent work highlights the potential for another measure derived from functional neuroimaging data, brain signal variability, to reveal insights into clinical conditions. Higher brain signal variability has previously been linked with optimal behavioral performance. At present, little is known regarding the relationship between resting-state brain signal variability and ADHD symptom severity. The current study examined the relationship between a measure of moment-to-moment brain signal variability called mean-square successive difference (MSSD) and ADHD symptomatology in a group of children (7–12 years old) with (n = 40) and without (n = 30) a formal diagnosis of ADHD. A categorical analysis comparing subjects with and without a clinical diagnosis of ADHD showed no differences in MSSD between groups. A dimensional analysis revealed a positive relationship between MSSD and overall ADHD symptom severity and inattention across children with and without an ADHD diagnosis. Specifically, this positive relationship was found in medial prefrontal areas comprising the default mode network. These results demonstrate a link between intrinsic brain signal variability and ADHD symptom severity that cuts across diagnostic categories, and point to a locus of dysfunction consistent with previous neuroimaging literature.

Model-based learning and individual differences in depression: The moderating role of stress

Inflexible decision-making has been proposed as a transdiagnostic risk factor for mood disorders. Evidence suggests that inflexible decision-making may emerge only when individuals are experiencing increased negative affect or stress. 151 participants completed symptom measures of depression and anxiety, followed by a two-stage decision-making task that distinguishes between habitual and goal-directed choice. An experimental manipulation to induce stress was introduced halfway through the task. Individuals with higher depression levels became less model-based after the manipulation than those with lower depression levels. There was no relationship between trait anxiety and the impact of the manipulation on decision-making. Controlling for main effects of anxiety did not attenuate the association between depression and impact of stress. Anhedonia was associated with the impact of the manipulation on model-based decision-making. These results suggest that risk for depression is associated with reflexive decision-making, but these effects may only emerge under conditions of stress.