[show abstract][hide abstract] ABSTRACT: 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 amygdala's 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 (9-17 years old) and 30 adults (21-40 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.
Journal of Cognitive Neuroscience 04/2008; 20(9):1565-82. · 4.49 Impact Factor
[show abstract][hide abstract] ABSTRACT: We examined whether face-emotion labeling deficits are illness-specific or an epiphenomenon of generalized impairment in pediatric psychiatric disorders involving mood and behavioral dysregulation.
Two hundred fifty-two youths (7-18 years old) completed child and adult facial expression recognition subtests from the Diagnostic Analysis of Nonverbal Accuracy (DANVA) instrument. Forty-two participants had bipolar disorder (BD), 39 had severe mood dysregulation (SMD; i.e., chronic irritability, hyperarousal without manic episodes), 44 had anxiety and/or major depressive disorders (ANX/MDD), 35 had attention-deficit/hyperactivity and/or conduct disorder (ADHD/CD), and 92 were controls. Dependent measures were number of errors labeling happy, angry, sad, or fearful emotions.
BD and SMD patients made more errors than ANX/MDD, ADHD/CD, or controls when labeling adult or child emotional expressions. BD and SMD patients did not differ in their emotion-labeling deficits.
Face-emotion labeling deficits differentiate BD and SMD patients from patients with ANX/MDD or ADHD/CD and controls. The extent to which such deficits cause vs. result from emotional dysregulation requires further study.
Journal of Child Psychology and Psychiatry 10/2007; 48(9):863-71. · 5.42 Impact Factor
[show abstract][hide abstract] ABSTRACT: A growing number of studies have found evidence that anxiety and depressive disorders are associated with atypical amygdala hyperactivation, which decreases with effective treatment. Interest has emerged in this phenomenon as a possible biological marker for individuals who are likely to benefit from tailored treatment approaches.
The present study was designed to examine relationships between pretreatment amygdala activity and treatment response in a sample of anxious children and adolescents.
Participants, who were diagnosed predominantly with generalized anxiety disorder (GAD), underwent functional magnetic resonance imaging (fMRI) scanning before treatment with fluoxetine or cognitive behavioral therapy (CBT).
Results indicated significant negative associations between degree of left amygdala activation and measures of posttreatment symptom improvement in the group, as a whole.
Taken together with research on associations between adult amygdala activation and treatment response, these findings suggest that patients whose pretreatment amygdala activity is the strongest may be particularly likely to respond well to such widely used treatments as selective serotonin reuptake inhibitor (SSRI) medications and CBT.
[show abstract][hide abstract] ABSTRACT: Considerable work implicates abnormal neural activation and disrupted attention to facial-threat cues in adult anxiety disorders. However, in pediatric anxiety, no research has examined attention modulation of neural response to threat cues.
To determine whether attention modulates amygdala and cortical responses to facial-threat cues differentially in adolescents with generalized anxiety disorder and in healthy adolescents.
Government clinical research institute.
Fifteen adolescents with generalized anxiety disorder and 20 controls.
Blood oxygenation level-dependent signal as measured via functional magnetic resonance imaging. During imaging, participants completed a face-emotion rating task that systematically manipulated attention.
While attending to their own subjective fear, patients, but not controls, showed greater activation to fearful faces than to happy faces in a distributed network including the amygdala, ventral prefrontal cortex, and anterior cingulate cortex (P<.05, small-volume corrected, for all). Right amygdala findings appeared particularly strong. Functional connectivity analyses demonstrated positive correlations among the amygdala, ventral prefrontal cortex, and anterior cingulate cortex.
This is the first evidence in juveniles that generalized anxiety disorder-associated patterns of pathologic fear circuit activation are particularly evident during certain attention states. Specifically, fear circuit hyperactivation occurred in an attention state involving focus on subjectively experienced fear. These findings underscore the importance of attention and its interaction with emotion in shaping the function of the adolescent human fear circuit.
Archives of General Psychiatry 02/2007; 64(1):97-106. · 13.77 Impact Factor