Lateralization of function in auditory cortex has remained a persistent puzzle. Previous studies using signals with differing spectrotemporal characteristics support a model in which the left hemisphere is more sensitive to temporal and the right more sensitive to spectral stimulus attributes. Here we use single-trial sparse-acquisition fMRI and a stimulus with parametrically varying segmental structure affecting primarily temporal properties. We show that both left and right auditory cortices are remarkably sensitive to temporal structure. Crucially, beyond bilateral sensitivity to timing information, we uncover two functionally significant interactions. First, local spectrotemporal signal structure is differentially processed in the superior temporal gyrus. Second, lateralized responses emerge in the higher-order superior temporal sulcus, where more slowly modulated signals preferentially drive the right hemisphere. The data support a model in which sounds are analyzed on two distinct timescales, 25-50 ms and 200-300 ms.

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.

Context Major depressive disorder (MDD) is associated with behavioral and neurophysiological evidence for mood-congruent processing biases toward explicitly presented, emotionally-valenced stimuli. However, few studies have investigated such biases toward implicitly presented stimuli. Objective To investigate differential amygdala responses to sad, happy and neutral faces presented below the level of explicit conscious awareness using a backward masking task in unmedicated subjects with MDD and healthy controls. Design Initial cross-sectional design followed by a longitudinal treatment trial using functional magnetic resonance imaging. Setting Psychiatric outpatient clinic at the National Institute of Mental Health. Participants Twenty-two unmedicated, currently-depressed subjects with MDD (dMDD), 16 unmedicated subjects with MDD in full remission (rMDD), and 25 healthy controls (HC). Interventions Ten dMDD subjects underwent 8 weeks of antidepressant treatment with the selective serotonin reuptake inhibitor, sertraline. Main Outcome Measures Amygdala region-of-interest and whole brain analyses evaluated the hemodynamic response during exposure to masked-sad versus masked-happy faces, to masked-sad versus neutral faces, and to masked-happy versus neutral faces. Results dMDD subjects showed greater amygdala responses than HC to masked-sad faces, while HC subjects showed greater amygdala responses to masked-happy faces. The bias toward sad faces also was evident in the rMDD relative to HC subjects and did not differ between the dMDD and rMDD subjects. This processing bias reversed toward the normative pattern in the dMDD subjects following sertraline treatment. Conclusions Emotional processing biases occur in the amygdala to sad faces presented below conscious awareness in currently-depressed or remitted-MDD subjects and to happy faces in controls. By influencing the salience of social stimuli, mood-congruent processing biases in the amygdala may contribute to dysfunction in conscious perceptions and social interactions in MDD. Our data suggest, however, that the negative bias resolves and a positive bias develops in MDD subjects during selective serotonin reuptake inhibitor treatment.

Reflecting a paradigm shift in clinical neuroscience, many chronic psychiatric illnesses are now hypothesized to result from perturbed neural development. However, most work in this area focuses on schizophrenia. Here, we extend this paradigm to pediatric bipolar disorder (BD), thus demonstrating traction in the developmental psychobiology perspective. To study amygdala dysfunction, we examined neural mechanisms mediating face processing in 22 youths (mean age 14.21 ؎ 3.11 yr) with BD and 21 controls of comparable age, gender, and IQ. Event-related functional MRI compared neural activation when attention was directed to emotional aspects of faces (hostility, subjects' fearfulness) vs. nonemotional aspects (nose width). Compared with controls, patients perceived greater hostility in neutral faces and reported more fear when viewing them. Also, compared with controls, patients had greater activation in the left amygdala, accumbens, putamen, and ventral prefrontal cortex when rating face hostility, and greater activation in the left amygdala and bilateral accumbens when rating their fear of the face. There were no between-group behavioral or neural differences in the nonemotional conditions. Results implicate deficient emotion-attention interactions in the pathophysiology of BD in youth and suggest that developmental psychobiology approaches to chronic mental illness have broad applicability.amygdala ͉ faces ͉ functional MRI R ecently, psychology and psychiatry have witnessed a major paradigm shift: virtually all chronic adult mental illnesses are now thought to result from long-term perturbations in neural development. Two lines of research support this perspective: family-based͞longitudinal studies and neurobiological studies. Family-based and longitudinal studies implicate developmental perturbations in a range of conditions, including behavior disorders, substance abuse, mood disorders, and psychoses (1-3). However, virtually all research on developmental neurobiology focuses on schizophrenia, where data implicate a neural circuit connecting the dorsolateral prefrontal cortex, striatum, and hippocampus (4, 5). Neurocognitive correlates of schizophrenia, such as deficient working memory, are thought to result from dysfunction in this circuit (6). An important next step is the extension of the developmental neurobiological approach to other mental illnesses and other neural systems associated with information processing and emotion regulation.For several reasons, bipolar disorder (BD) is an ideal illness in which to expand the emerging developmental paradigm by conducting neurobiologically oriented developmental research. BD causes marked disruption in social, academic, and family function. Major questions persist concerning the boundaries of the condition in children; neurobiological data might ultimately resolve them. Most importantly, research in adult patients and animals implicates a circuit encompassing the amygdala, striatum, and ventral prefrontal cortex (VPFC) in the pathophysiology of BD (7). This circu...