Roxann Roberson-Nay

A developmental examination of amygdala response to facial expressions

Several lines of evidence implicate the amygdala in face-emotion processing, particularly for fearful facial expressions. Related findings suggest that face-emotion processing engages the amygdala within an interconnected circuitry that can be studied using a functional-connectivity approach. Past work also underscores important functional changes in the amygdala during development. Taken together, prior research on amygdala function and development reveals a need for more work examining developmental changes in the amygdalas response to fearful faces and in amygdala functional connectivity during face processing. The present study used event-related functional magnetic resonance imaging to compare 31 adolescents (917 years old) and 30 adults (2140 years old) on activation to fearful faces in the amygdala and other regions implicated in face processing. Moreover, these data were used to compare patterns of amygdala functional connectivity in adolescents and adults. During passive viewing, adolescents demonstrated greater amygdala and fusiform activation to fearful faces than did adults. Functional connectivity analysis revealed stronger connectivity between the amygdala and the hippocampus in adults than in adolescents. Within each group, variability in age did not correlate with amygdala response, and sex-related developmental differences in amygdala response were not found. Eye movement data collected outside of the magnetic resonance imaging scanner using the same task suggested that developmental differences in amygdala activation were not attributable to differences in eye-gaze patterns. Amygdala hyperactivation in response to fearful faces may explain increased vulnerability to affective disorders in adolescence; stronger amygdala-hippocampus connectivity in adults than adolescents may reflect maturation in learning or habituation to facial expressions.

Attention Alters Neural Responses to Evocative Faces in Behaviorally Inhibited Adolescents

Behavioral inhibition (BI) is a risk factor for anxiety disorders. While the two constructs bear behavioral similarities, previous work has not extended these parallels to the neural level. This study examined amygdala reactivity during a task previously used with clinically anxious adolescents. Adolescents were selected for enduring patterns of BI or non-inhibition (BN). We examined amygdala response to evocative emotion faces in BI (N=10, mean 12.8 years) and BN (N=17, mean 12.5 years) adolescents while systematically manipulating attention. Analyses focused on amygdala response during subjective ratings of internal fear (constrained attention) and passive viewing (unconstrained attention) during the presentation of emotion faces (Happy, Angry, Fearful, and Neutral). BI adolescents, relative to BN adolescents, showed exaggerated amygdala response during subjective fear ratings and deactivation during passive viewing, across all emotion faces. In addition, the BI group showed an abnormally high amygdala response to a task condition marked by novelty and uncertainty (i.e., rating fear state to a Happy face). Perturbations in amygdala function are evident in adolescents temperamentally at risk for anxiety. Attention state alters the underlying pattern of neural processing, potentially mediating the observed behavioral patterns across development. BI adolescents also show a heightened sensitivity to novelty and uncertainty, which has been linked to anxiety. These patterns of reactivity may help sustain early temperamental biases over time and contribute to the observed relation between BI and anxiety.

Striatal Functional Alteration in Adolescents Characterized by Early Childhood Behavioral Inhibition

The temperamental style of behavioral inhibition has been characterized by exaggerated behavioral and neural responses to cues signaling threat. Virtually no work, however, has addressed whether behavioral inhibition may also confer heightened brain activation in response to positively valenced incentives. We used event-related functional MRI (fMRI) and a monetary incentive delay task to examine whether the neural response to incentives is also greater in adolescents characterized as behaviorally inhibited early in life compared with those characterized as non-inhibited. Whereas task performance did not differ between groups, fMRI revealed greater striatal activation to incentives in behaviorally inhibited adolescents than in non-inhibited adolescents. This was regardless of whether the incentive was an anticipated gain or loss. Alteration in neural systems underlying behavior modulated by both negative and positive contingencies may represent a correlate of behavioral inhibition that also underlies vulnerability to various forms of developmental psychopathology.

Fear Conditioning in Adolescents With Anxiety Disorders: Results From a Novel Experimental Paradigm

OBJECTIVE Considerable research examines fear conditioning in adult anxiety disorders but few studies examine youths. Adult data suggest that anxiety disorders involve elevated fear but intact differential conditioning. We used a novel paradigm to assess fear conditioning in pediatric anxiety patients. METHOD Sixteen individuals with anxiety disorders and 38 healthy comparisons viewed two photographs of actresses displaying neutral expressions. One picture served as the conditioned stimulus (CS), paired with a fearful expression and a shrieking scream (CS+), whereas the other picture served as a CS unpaired with the aversive outcome (CS-). Conditioning was indexed by self-reported fear. Subjects participated in two visits involving conditioning and extinction trials. RESULTS Both groups developed greater fear of the CS+ relative to CS-. Higher fear levels collapsed across each CS characterized anxious relative to healthy subjects, but no significant interaction between group and stimulus type emerged. Fear levels at visit 1 predicted avoidance of visit 2. Fear levels to both CS types showed stability even after extinction. CONCLUSIONS Consistent with adult data, pediatric anxiety involves higher fear levels following conditioning but not greater differential conditioning. Extending these methods to neuroimaging studies may elucidate neural correlates of fear conditioning. Implications for exposure therapies are discussed.

Increased Amygdala Activity During Successful Memory Encoding in Adolescent Major Depressive Disorder: An fMRI Study

BACKGROUND Although major depressive disorder (MDD) represents one of the most serious psychiatric problems afflicting adolescents, efforts to understand the neural circuitry of adolescent MDD have lagged behind those of adult MDD. This study tests the hypothesis that adolescent MDD is associated with abnormal amygdala activity during evocative-face viewing. METHODS Using functional magnetic resonance imaging (fMRI), between-group differences among MDD (n = 10), anxious (n = 11), and non-psychiatric comparisons (n = 23) were examined during successful vs. unsuccessful face encoding, with encoding success measured post-scan. RESULTS Compared to healthy adolescents, MDD patients exhibited poorer memory for faces. fMRI analyses accounted for this performance difference through event-related methods. In an analysis comparing successful vs. unsuccessful face encoding, MDD patients exhibited greater left amygdala activation relative to healthy and anxious youth. CONCLUSIONS Given prior findings among adults, this study suggests that adolescent and adult MDD may involve similar underlying abnormalities in amygdala functioning.

CHILDHOOD SEPARATION ANXIETY DISORDER AND ADULT ONSET PANIC ATTACKS SHARE A COMMON GENETIC DIATHESIS

Childhood separation anxiety disorder (SAD) is hypothesized to share etiologic roots with panic disorder. The aim of this study was to estimate the genetic and environmental sources of covariance between childhood SAD and adult onset panic attacks (AOPA), with the primary goal to determine whether these two phenotypes share a common genetic diathesis.

Panic disorder and its subtypes: a comprehensive analysis of panic symptom heterogeneity using epidemiological and treatment seeking samples.

BACKGROUND Panic disorder (PD) is a heterogeneous syndrome that can present with a variety of symptom profiles that potentially reflect distinct etiologic pathways. The present study represents the most comprehensive examination of phenotypic variance in PD with and without agoraphobia for the purpose of identifying clinically relevant and etiologically meaningful subtypes. METHOD Latent class (LC) and factor mixture analysis were used to examine panic symptom data ascertained from three national epidemiologic surveys [Epidemiological Catchment Area (ECA), National Comorbidity Study (NCS), National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), Wave 1], a twin study [Virginia Adult Twin Study of Psychiatric and Substance Use Disorders (VATSPSUD)] and a clinical trial (Cross-National Collaborative Panic Study [CNCPS]). RESULTS Factor mixture models (versus LC) generally provided better fit to panic symptom data and suggested two panic classes for the ECA, VATSPSUD and CNCPS, with one class typified by prominent respiratory symptoms. The NCS yielded two classes, but suggested both qualitative and quantitative differences. The more contemporary NESARC sample supported a two and three class model, with the three class model suggesting two variants of respiratory panic. The NESARCs three class model continued to provide the best fit when the model was restricted to a more severe form of PD/panic disorder with agoraphobia. CONCLUSIONS Results from epidemiologic and clinical samples suggest two panic subtypes, with one subtype characterized by a respiratory component and a second class typified by general somatic symptoms. Results are discussed in light of their relevance to the etiopathogenesis of PD.

A Genetically Informed Study of the Longitudinal Relation Between Irritability and Anxious/Depressed Symptoms

OBJECTIVE Little is known about the longitudinal genetic and environmental association between juvenile irritability and symptoms of anxiety and depression. This studys goal was to assess the relationship between these constructs across a critical developmental period spanning childhood to young adulthood. METHOD Parents (n = 1,348 twin pairs) from the Swedish Twin Study of Child and Adolescent Development completed the Child/Adult Behavior Checklist (CBCL/ABCL) about their twin children. Data were collected during a prospective, 4-wave study starting in childhood (ages 8-9 years) and ending in young adulthood (ages 19-20 years). An irritability score and an anxious/depressed score were computed from CBCL/ABCL item endorsements. Genetically informative cross-lagged models were used to estimate the genetic and environmental relationship between these 2 constructs across time. RESULTS Our models suggested that irritability more strongly predicted anxious/depressed symptoms than vice versa, consistent with a causal role of irritability on anxiety/depression at older ages. This relationship was significant only in late childhood/early adolescence. Additive genetic and unique environmental factors were significant contributors to both irritability and anxious/depressed symptoms and were both specific to and shared between these 2 constructs. The same common environmental factors influenced both constructs, although these factors accounted for a smaller amount of variance than genetic or unique environmental factors. CONCLUSION This study adds to our understanding of the developmental relationship between irritability and anxious/depressed symptoms and the contribution of genes and environmental factors to their association across development. Findings suggest the need to monitor for emergence of internalizing symptoms in irritable children and their potential need for therapeutic intervention.

Associations among trauma, posttraumatic stress disorder, cannabis use, and cannabis use disorder in a nationally representative epidemiologic sample.

Research in community and clinical samples has documented elevated rates of cannabis use and cannabis use disorders (CUDs) among individuals with trauma exposure and posttraumatic stress disorder (PTSD). However, there is a lack of research investigating relations between, and correlates of, trauma and cannabis phenotypes in epidemiologic samples. The current study examined associations between trauma (i.e., lifetime trauma exposure and PTSD) and cannabis phenotypes (i.e., lifetime cannabis use and CUD) in a nationally representative sample. Participants were individuals who participated in Waves 1 and 2 of the National Epidemiologic Survey on Alcohol and Related Conditions (n = 34,396; 52.4% women; age, M = 48.0 years, SD = 16.9). Lifetime DSM-IV Criterion A trauma exposure was significantly associated with lifetime cannabis use (OR = 1.215) but was only marginally associated with CUD (OR = 0.997). Within the trauma-exposed sample, lifetime PTSD showed a significant association with CUD (OR = 1.217) but was only marginally associated with lifetime cannabis use (OR = 0.992). Partially consistent with hypotheses, lifetime trauma was associated with greater odds of lifetime cannabis use, whereas PTSD was associated with greater odds of CUD. Longitudinal research investigating patterns of onset of these events/disorders is needed.

Measuring Social Anxiety in College Students: A Comprehensive Evaluation of the Psychometric Properties of the SPAI-23.

Social anxiety disorder (SAD) is 1 of the most prevalent psychological disorders, and among college students in particular, social anxiety has been associated with other problems such as substance use problems and increased vulnerability to other psychiatric disorders. The Social Phobia and Anxiety Inventory-23 (SPAI-23; Roberson-Nay, Strong, Nay, Beidel, & Turner, 2007) may be a useful, brief measure of problematic social anxiety in college students. Results from 4 studies (total n = 2,436) using the SPAI-23 with college student samples are presented. Scores on the SPAI-23 demonstrated strong convergent validity with other measures of social anxiety and discriminant validity as evidenced by lower correlations with measures of dissimilar constructs. Difference scores on the SPAI-23 also demonstrated adequate test-retest reliability over 5 ½ weeks (r = .72). Exploratory factor analysis suggested a two-factor structure: social anxiety and agoraphobia. Finally, differential item function analyses suggested that the items function similarly in men and women. In conclusion, the SPAI-23 demonstrated strong psychometric properties for use with college students.