Context Generalized social phobia (GSP) is characterized by fear/avoidance of social situations. Previous studies have examined the neural responses in GSP to one class of social stimuli, facial expressions. However, studies have not examined the neural response in GSP to another equally important class of social stimuli, the communication of praise or criticism. Objective To examine the neural response to receipt of praise or criticism in GSP; specifically, to determine whether patients with GSP show an increased response to the receipt of both praise and criticism and whether self-relevance modulates this relationship. Design Case-control study. Setting Government clinical research institute. Participants Unmedicated individuals with GSP (n=17) and age-, IQ-, and sex-matched healthy comparison individuals (n=17). Main Outcome Measure Blood oxygenation level–dependent signal, as measured via functional magnetic resonance imaging. During functional magnetic resonance imaging scans, individuals read positive (eg, You are beautiful), negative (eg, You are ugly), and neutral (eg, You are human) comments that could be either about the self or about somebody else (eg, He is beautiful). Results Hypothesized significant group×valence×referent interactions were observed within regions of the medial prefrontal cortex and bilateral amygdala. In these regions, the patients with GSP showed significantly increased blood oxygenation level–dependent responses, relative to comparison individuals, to negative comments (criticism) referring to themselves. However, in contrast, there were no significant group differences with respect to negative comments referring to others or neutral or positive comments referring to self or others. Conclusions These results implicate the medial prefrontal cortex, involved in the representation of the self, together with the amygdala, in the pathophysiology of GSP. Further, findings demonstrate a meaningful effect of psychological context on neural-circuitry hyperactivity in GSP.

The automated volumetric output of FreeSurfer and Individual Brain Atlases using Statistical Parametric Mapping (IBASPM), two widely used and well published software packages, was examined for accuracy and consistency relative to auto-assisted manual (AAM) tracings (i.e., manual correction of automated output) when measuring the caudate, putamen, amygdala, and hippocampus in the baseline scans of 120 HIV-infected patients (86.7% male, 47.3±6.3 y.o., mean HIV duration 12.0±6.3 years) from the NIH-funded HIV Neuroimaging Consortium (HIVNC) cohort. The data was examined for accuracy and consistency relative to auto-assisted manual tracing, and construct validity was assessed by correlating automated and AAM volumetric measures with relevant clinical measures of HIV progression. When results were averaged across all patients in the eight structures examined, FreeSurfer achieved lower absolute volume difference in five, higher sensitivity in seven, and higher spatial overlap in all eight structures. Additionally, FreeSurfer results exhibited less variability in all measures. Output from both methods identified discrepant correlations with clinical measures of HIV progression relative to AAM segmented data. Overall, FreeSurfer proved more effective in the context of subcortical volumetry in HIV-patients, particularly in a multi-site cohort study such as this. These findings emphasize that regardless of the automated method used, visual inspection of segmentation output, along with manual correction if necessary, remains critical to ensuring the validity of reported results.

What makes us become aware? A popular hypothesis is that if cortical neurons fire in synchrony at a certain frequency band (gamma), we become aware of what they are representing. We tested this hypothesis adopting brain-imaging techniques with good spatiotemporal resolution and frequency-specific information. Specifically, we examined the degree to which increases in event-related synchronization (ERS) in the gamma band were associated with awareness of a stimulus (its detectability) and/or the emotional content of the stimulus. We observed increases in gamma band ERS within prefrontal–anterior cingulate, visual, parietal, posterior cingulate, and superior temporal cortices to stimuli available to conscious awareness. However, we also observed increases in gamma band ERS within the amygdala, visual, prefrontal, parietal, and posterior cingulate cortices to emotional relative to neutral stimuli, irrespective of their availability to conscious access. This suggests that increased gamma band ERS is related to, but not sufficient for, consciousness.

Background This study aimed to determine whether patients with post-traumatic stress disorder (PTSD) show difficulty in recruitment of the regions of the frontal and parietal cortex implicated in top-down attentional control in the presence and absence of emotional distracters. Method Unmedicated individuals with PTSD (n=14), and age-, IQ- and gender-matched individuals exposed to trauma (n=15) and healthy controls (n=19) were tested on the affective number Stroop task. In addition, blood oxygen level-dependent responses, as measured via functional magnetic resonance imaging, were recorded. Results Patients with PTSD showed disrupted recruitment of lateral regions of the superior and inferior frontal cortex as well as the parietal cortex in the presence of negative distracters. Trauma-comparison individuals showed indications of a heightened ability to recruit fronto-parietal regions implicated in top-down attentional control across distracter conditions. Conclusions These results are consistent with suggestions that emotional responsiveness can interfere with the recruitment of regions implicated in top-down attentional control ; the heightened emotional responding of patients with PTSD may lead to the heightened interference in the recruitment of these regions.