***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: The amygdala is known to play an important role in conscious and unconscious processing of emotional and highly arousing stimuli . Neuroanatomical evidence suggests that the amygdala participates in the control of autonomic responses , such as skin conductance responses ( SCRs ) , elicited by emotionally salient stimuli , but little is known regarding its functional role in such control . We investigated this issue by showing emotional visual stimuli of varying arousal to patients with left ( n = 12 ) , right ( n = 8) , and bilateral ( n = 3 ) amygdala damage and compared their results with those from 38 normal controls .  Stimuli were presented both subliminally ( using backward masking ) and supraliminally under lateralized presentation to one visual hemifield . We collected SCRs as a physiological index of emotional responses . Subjects subsequently rated each stimulus on valence and arousal under free viewing conditions . There were two key findings : ( 1 ) impaired overall SCR after right amygdala damage ; and ( 2 ) impaired correlation of SCR with the rated arousal of the stimuli after left amygdala damage . The second finding was strengthened further by finding a positive correlation between the evoked SCR magnitude and postsurgery amygdala volume , indicating impaired autonomic responses with larger tissue damage . Bilateral amygdala damage result ed in severe impairments on both of the above measures . Our results provide support for the hypothesis that the left and right amygdalae subserve different functions in emotion processing : the left may decode the arousal signaled by the specific stimulus , whereas the right may provide a global level of autonomic activation triggered automatically by any arousing stimulus Individuals with Williams syndrome ( WS ) are well known for their friendly behaviour and tendency to approach strangers indiscriminately as if everybody were their friend . This tendency to approach strangers is mirrored in their ratings of unfamiliar  face stimuli .  Here we examined their perception of unfamiliar expressive faces and found that individuals with WS do not always see faces as being highly approachable . Happy faces were rated as more approachable by individuals with WS than by controls . In contrast , the other less approachable face stimuli were rated lower on approachability by individuals with WS than by controls . Thus , it appears that although individuals with WS will discriminate people in terms of approachability , they have difficulty inhibiting their strong compulsion towards social interaction . The form of this strong pro-social compulsion is discussed both in terms of friendliness and in terms of the heightened salience of social stimuli ( social stimulus attraction ) In this study we investigated whether event-related near-infrared spectroscopy ( NIRS ) is suitable to measure changes in brain activation of the occipital cortex modulated by the emotional content of the visual stimuli . As we found in a previous pilot study that only positive but not negative stimuli differ from neutral stimuli ( with respect to oxygenated haemoglobin ) , we now measured the event-related EEG potentials and NIRS simultaneously during the same session . Thereby , we could evaluate whether the subjects ( n = 16 ) processed the positive as well as the negative emotional stimuli in a similar way . During the task , the subjects passively viewed positive , negative , and neutral emotional pictures ( 40 presentations were shown in each category , and pictures were taken from the International Affective Picture System , IAPS ) . The stimuli were presented for 3 s in a r and omized order ( with a mean of 3 s interstimulus interval ) . During the task , we measured the  event-related EEG potentials  over the electrode positions O1 , Oz , O2 , and Pz and the changes of oxygenated and deoxygenated haemoglobin by multichannel NIRS over the occipital cortex . The EEG results clearly show an increased early posterior negativity over the occipital cortex for both positive as well as negative stimuli compared to neutral . The results for the NIRS measurement were less clear . Although positive as well as negative stimuli lead to significantly higher decrease in deoxygenated haemoglobin than neutral stimuli , this was not found for the oxygenated haemoglobin Neuroimaging studies using angry or contemptuous human facial photographic stimuli have suggested amygdala hyper-responsivity in social anxiety disorder ( SAD ) . We sought to determine if an angry " schematic face " ( simple line drawing ) would evoke exaggerated amygdalar responses in SAD patients compared with healthy control ( HC ) subjects .  Angry , happy , and neutral schematic faces were overtly presented to matched cohorts of 11 SAD and 11 HC subjects for passive viewing , whereas brain functional magnetic resonance imaging signal was measured at 1.5 Tesla . Voxel-wise analyses were performed using a r and om effects model in SPM99 . Compared with HC subjects , SAD patients exhibited exaggerated responses in the right amygdala for the Angry versus Neutral contrast . The findings of exaggerated amygdala responses to angry schematic faces in SAD converge with results from earlier neuroimaging studies and illustrate the potential utility of schematic faces for probing amygdala function in psychiatric disorders . One prospect i ve advantage of schematic faces is that they may minimize confounds related to gender , age , or race effects . However , extending earlier findings in healthy subjects , schematic faces appear more effective for probing amygdala responses to arousal-based ( Angry versus Neutral ) as opposed to valence-based ( Angry versus Happy ) contrasts Williams syndrome ( WMS ) , a rare disorder with a distinctive profile of medical , psychological , neurophysiological and neuroanatomical characteristics , results from hemizygous deletion of about 20 genes . The phenotype exhibits specific dissociations in higher cognitive functions : general cognitive deficits but spared linguistic abilities ; extreme spatial cognitive deficits , but intact face processing . Of special interest is an unusual social phenotype in WMS : an overly friendly , engaging personality and excessive sociability with strangers . In this first experimental study of social behavior in WMS , we report that  WMS subjects show an abnormal positive bias in their social judgments of unfamiliar individuals , consistent with their behavior in real life . Our findings contribute to an underst and ing of the neural and genetic bases of human social  behavior 
    Output:
    
We found evidence for both common and distinct patterns of neural activation .
Limbic engagement was common to SAD and WS during facial emotion processing , although we observed opposite patterns of activation for each disorder .
Compared to HC , SAD cases showed hyperactivation of the amygdala , the parahippocampal gyrus and the globus pallidus .
Compared to controls , participants with WS showed hypoactivation of these regions .
Differential activation in a number of regions specific to either condition was also identified : SAD cases exhibited greater activation of the insula , putamen , the superior temporal gyrus , medial frontal regions and the cuneus , while WS subjects showed decreased activation in the inferior region of the parietal lobule .
The identification of limbic structures as a shared correlate and the patterns of activation observed for each condition may reflect the aberrant patterns of facial emotion processing that the two conditions share , and may contribute to explaining part of the underlying neural substrate of exaggerated/diminished fear responses to social cues that characterize SAD and WS respectively .
We believe that insights from WS and the inclusion of this syndrome as a control group in future experimental studies may improve our underst and ing of the neural correlates of social fear in general , and of SAD in particular