***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: BACKGROUND We investigated the differential effects of serotonergic and noradrenergic antidepressants on brain activation in patients with major depressive disorder during a Stroop task . We predicted that pretreatment hyperactivity in the rostral anterior cingulate cortex would predict better treatment outcomes . METHODS In total , 20 patients underwent naturalistic open-label clinical treatment with citalopram ( n = 12 ) or reboxetine ( n = 8) . We performed functional magnetic resonance imaging at baseline and after 6 weeks of treatment . RESULTS There were no significant group differences in clinical characteristics , treatment outcomes or baseline fMRI activations . The group by time interaction revealed significant voxels in the right amygdala-hippocampus complex ( p < 0.05 , family-wise error corrected by use of the bilateral amygdala and hippocampus mask image as a small volume ) , indicating a posttreatment blood oxygen level- dependent signal decrease in the citalopram group . Pretreatment hyperactivity in the rostral anterior cingulate cortex was not related to symptom improvement . LIMITATIONS Our study was a nonr and omized clinical trial . CONCLUSION These results indicate that serotonergic and noradrenergic antidepressants have a differential effect on brain activity , especially in the amygdala and hippocampus BACKGROUND Previous studies have shown that major depression is frequently accompanied by hypercortisolemia . There is some evidence suggesting that an increase in the glucocorticoid levels may make hippocampal cells more vulnerable to insults caused by hypoxia , hypoglycemia , or excitatory neurotransmitters . Using magnetic resonance imaging ( MRI ) , the hippocampi of patients with major depression were measured and compared with values observed in control subjects . METHODS Thirty-eight patients with primary unipolar major depression were recruited . Twenty control subjects were matched for age , gender , and years of education . The hippocampal volume was measured from coronal MRI scans in all of the subjects . Patients were also grouped and compared as responders and nonresponders to treatment with fluoxetine of 20 mg/day , for 8 weeks .  Hamilton Depression Rating Scale ( HDRS ) was used to determine the severity of depression . RESULTS No significant differences were observed between the hippocampal volumes of patients with major depression and control subjects ; however , a significant correlation was observed between the left hippocampal volume of men and their HDRS baseline values . In addition , female responders had a statistically significant higher mean right hippocampal volume than nonresponders . CONCLUSIONS The results of our study indicate no reduction in the volume of the hippocampus in patients with major depression . Nonetheless , the results do suggest that the effects of disease severity , gender , and treatment response may influence hippocampal volume BACKGROUND Affective facial processing is an important component of interpersonal relationships . The neural substrate has been examined following treatment with antidepressant medication but not with psychological therapies . The present study investigated the neural correlates of implicit processing of sad facial expressions in depression pretreatment and posttreatment with cognitive behavioral therapy ( CBT ) . METHODS The patient group consisted of 16 medication-free subjects ( mean age 40 years ) with a DSM-IV diagnosis of acute unipolar major depression , and the comparison group were 16 matched healthy volunteers . Subjects participated in a prospect i ve study with functional magnetic resonance imaging ( fMRI ) at weeks 0 and 16 . During the fMRI scans , subjects performed an affect recognition task with facial stimuli morphed to display varying intensities of sadness . Patients received 16 sessions of CBT . Functional magnetic resonance imaging data were analyzed for the mean activation and differential response to variable intensity ( load-response ) of facial affect processing . RESULTS During an acute depressive episode , patients showed elevated amygdala-hippocampal activity relative to healthy individuals . Baseline dorsal anterior cingulate activity in patients showed a significant relationship with subsequent clinical response . CONCLUSIONS These data provide further support for elevated amygdala activity in depression and suggest that anterior cingulate activity may be a predictor of treatment response to both pharmacotherapy and CBT Major depressive disorder ( MDD ) is characterized by the presence of disturbances in emotional processing . However , the neural correlates of these alterations , and how they may be affected by therapeutic interventions , remain unclear . The present study addressed these issues in a preliminary investigation using functional magnetic resonance imaging ( fMRI ) to examine neural responses to positive , negative , and neutral pictures in unmedicated MDD patients ( N = 22 ) versus controls ( N = 14 ) . After this initial scan , MDD patients were treated with cognitive behavioral therapy ( CBT ) and scanned again after treatment . Within regions that showed pre-treatment differences between patients and controls , we tested the association between pre-treatment activity and subsequent treatment response as well as activity changes from pre- to post-treatment . This study yielded three main findings . First , prior to treatment and relative to controls , patients exhibited overall reduced activity in the ventromedial prefrontal cortex ( PFC ) , diminished discrimination between emotional and neutral items in the amygdala , cau date , and hippocampus , and enhanced responses to negative versus positive stimuli in the left anterior temporal lobe ( ATL ) and right dorsolateral PFC . Second , CBT-related symptom improvement in MDD patients was predicted by increased activity at baseline in ventromedial PFC as well as the valence effects in the ATL and dorsolateral PFC . Third , from pre- to post-treatment , MDD patients exhibited overall increases in ventromedial PFC activation , enhanced arousal responses in the amygdala , cau date , and hippocampus , and a reversal of valence effects in the ATL . The study was limited by the relatively small sample that was able to complete both scan sessions , as well as an inability to determine the influence of comorbid disorders within the current sample . Nevertheless , components of the neural networks corresponding to emotion processing disturbances in MDD appear to resolve following treatment and are predictive of treatment response , possibly reflecting improvements in emotion regulation processes in response to CBT OBJECTIVE Antidepressants with different mechanisms of action might have different effects on brain functions . The aim of the study was therefore to investigate effects of 2 antidepressants on brain activation and to identify predictors for therapy response . METHOD Twenty-four untreated patients with major depressive disorder ( according to Structured Clinical Interview for DSM-IV ) were enrolled in a prospect i ve , r and omized , 4-week trial with mirtazapine and venlafaxine . Functional magnetic resonance imaging ( fMRI ) was performed at baseline and after 4 weeks in the patients and in 15 healthy controls . The primary outcome measure was fMRI blood-oxygen-level dependence ( BOLD ) activation .  The patients were recruited in 2007 and 2008 . RESULTS Comparison between patients and controls revealed that emotional face matching elicited enhanced activation in the anterior cingulate cortex ( ACC ) , dorsomedial prefrontal cortex , dorsolateral prefrontal cortex , and basal ganglia in patients . During treatment , a significant decrease of BOLD responses was seen in the hippocampus , basal ganglia , thalamus , and cerebellum of venlafaxine-treated patients , and a significant increase in BOLD responses was seen in the middle cingulate gyrus and supplementary motor area of mirtazapine-treated patients ( P < .05 , family wise error [ FWE ] cluster-level corrected ) . Larger BOLD responses in the left fusiform gyrus at baseline predicted a better response to venlafaxine , and smaller BOLD responses in the right rol and ic operculum at baseline predicted a better response to mirtazapine ( P < .05 , FWE cluster-level corrected ) . CONCLUSIONS These fMRI results indicate that antidepressants with different mechanisms of action have different effects on brain function . It therefore seems that fMRI can be used for therapy evaluation and response prediction and can facilitate the development of new pharmaceuticals Behavioral studies suggest that emotional reactivity in depressed persons predicts subsequent symptom reduction . Using functional magnetic resonance imaging in a prospect i ve study , we show that greater amygdala activation to emotional facial expressions among depressed patients predicts symptom reduction 8 months later , controlling for initial depression severity and medication status . Functional magnetic resonance imaging may thus be used as a method to identify neural markers in depressed patients at risk for poor outcome The functional neuroanatomy of verbal working memory is a potential diagnostic biomarker for depression . Twenty patients with unipolar depression and 20 healthy controls performed a variable load version ( n-back ) of the task . Functional MRI data were analysed with support vector machine methods . Diagnostic classification was highest at the mid-level of task difficulty ( 2-back ) ( sensitivity 65 % , specificity 70 % , P<0.009 ) . Significant classification of clinical response ( ≥50 % reduction in clinical symptom ratings ) was found at the most difficult level ( 3-back ) ( sensitivity 85 % , specificity 52 % , P<0.003 ) . The functional neuroanatomy of verbal working memory provides a statistically significant but clinical ly moderate contribution as a diagnostic biomarker for depression , whereas its potential as a neural predictor of clinical response requires further investigation OBJECTIVE Selective serotonin reuptake inhibitors ( SSRIs ) are widely used to treat depression , but the rates , timing , and baseline predictors of remission in " real world " patients are not established . The authors ' primary objectives in this study were to evaluate the effectiveness of citalopram , an SSRI , using measurement-based care in actual practice , and to identify predictors of symptom remission in out patients with major depressive disorder . METHOD This clinical study included out patients with major depressive disorder who were treated in 23 psychiatric and 18 primary care " real world " setting s. The patients received flexible doses of citalopram prescribed by clinicians for up to 14 weeks . The clinicians were assisted by a clinical research coordinator in the application of measurement-based care , which included the routine measurement of symptoms and side effects at each treatment visit and the use of a treatment manual that described when and how to modify medication doses based on these measures . Remission was defined as an exit score of < or=7 on the 17-item Hamilton Depression Rating Scale ( HAM-D ) ( primary outcome ) or a score of < or=5 on the 16-item Quick Inventory of Depressive Symptomatology , Self-Report ( QIDS-SR ) ( secondary outcome ) . Response was defined as a reduction of > or=50 % in baseline QIDS-SR score . RESULTS Nearly 80 % of the 2,876 out patients in the analyzed sample had chronic or recurrent major depression ; most also had a number of comorbid general medical and psychiatric conditions . The mean exit citalopram dose was 41.8 mg/day . Remission rates were 28 % ( HAM-D ) and 33 % ( QIDS-SR ) . The response rate was 47 % ( QIDS-SR ) . Patients in primary and psychiatric care setting s did not differ in remission or response rates . A substantial portion of participants who achieved either response or remission at study exit did so at or after 8 weeks of treatment . Participants who were Caucasian , female , employed , or had higher levels of education or income had higher HAM-D remission rates ; longer index episodes , more concurrent psychiatric disorders ( especially anxiety disorders or drug abuse ) , more general medical disorders , and lower baseline function and quality of life were associated with lower HAM-D remission rates . CONCLUSIONS The response and remission rates in this highly generalizable sample with substantial axis I and axis III comorbidity closely resemble those seen in 8-week efficacy trials . The systematic use of easily implemented measurement-based care procedures may have assisted in achieving these results The authors investigated whether there were differences in cau date and lenticular nucleus volumes in depressed patients relative to comparison subjects , and whether differences in basal ganglia volume were associated with treatment response to fluoxetine . Brain magnetic resonance images were obtained from 38 unipolar depressed patients and 20 matched comparison subjects . Patients were divided into groups of ' responders ' and ' non-responders ' based on change in the 17-item Hamilton Depression Rating Scale ( HDRS ) score after a 10-week open trial of fluoxetine , 20 mg/day . There were no group mean differences in cau date and lenticular nucleus volumes between patients and comparison subjects . Female treatment responders tended to have larger cau date nucleus volumes than male ' responders ' , and also larger right cau date nucleus volumes than their female ' non-responder ' counterparts . Baseline HDRS scores correlated negatively with left cau date nucleus volume in depressed patients . Thus , in mild to moderately depressed patients , we were unable to find differences in cau date and lenticular nucleus-gray matter volumes relative to comparison subjects . One possible reason is that cau date nucleus-gray matter volume and severity of depression are inversely correlated , suggesting that severity of depression may be an important covariate when comparing cau date volumes in depressed patients and control subjects BACKGROUND Brain imaging studies of major depressive disorder have shown alterations in the brain regions typically involved in episodic memory , including the prefrontal cortex and medial temporal areas . Some studies of major depressive disorder have linked episodic memory performance to treatment response . In this study , we sought to identify brain regions whose activity , measured during the encoding of pictures , predicted symptomatic improvement after 8 weeks of citalopram treatment . METHODS We included 20 unmedicated depressed patients . These patients performed an episodic recognition memory task during functional magnetic resonance imaging . During the encoding phase , 150 pictures depicting emotionally positive , negative or neutral content were presented , and the participants 
    Output:
    
Regional activations with prognostic value include the well replicated finding that increased baseline activity in the anterior cingulate is predictive of a higher likelihood of improvement .
As well , increased baseline activation in the insula and striatum is associated with higher likelihood of a poorer clinical response .
Structural neuroimaging studies indicated that a decrease in right hippocampal volume is a statistically significant predictor of poorer treatment response .
Overall , the predictive information that is measurable with brain imaging techniques is both multimodal and regionally distributed as it contains functional as well as structural correlates which encompass several brain regions within a frontostriatal-limbic network .