Blunted rostral anterior cingulate response during a simplified decoding task of negative emotional facial expressions in alcoholic patients.

BACKGROUND: Alcoholism is characterized by deficits in emotional functioning as well as by deficits in cognitive functioning. However, most brain imaging research on alcoholism has focused on cognition rather than emotion. METHOD: We used an event-related functional magnetic imaging approach to examine alcoholics' brain blood oxygenation level dependent (BOLD) response to evaluation of emotional stimuli and to compare their response to that of nonalcoholic controls. The task used was a simplified variant of a facial emotion-decoding task in which subjects determined the intensity level of a target emotion displayed as a facial expression. Facial expressions of happy, sad, anger, disgust, and fear were used as stimuli. RESULTS: Alcoholics and controls did not differ in accurately identifying the intensity level on the simple emotional decoding task but there were significant differences in their BOLD response during evaluation of facial emotion. In general, alcoholics showed less brain activation than nonalcoholic controls. The greatest differences in activation were during decoding of facial expressions of fear and disgust during which alcoholics had significantly less activation than controls in the affective division of the anterior cingulate cortex (ACC). Alcoholics also had significantly less activation than controls in the affective division of the ACC, while viewing sad faces. Only to facial expressions of anger did the alcoholics show significant activation in the affective ACC and in this case, their BOLD response did not significantly differ from that of the controls. CONCLUSION: Alcoholics show a deficit in the function of the affective division of the ACC during evaluation of negative facial emotions that can serve as cues for flight or avoidance. This deficit may underlie some of the behavioral dysfunction in alcoholism.

Single subject image analysis using the complex general linear model--an application to functional magnetic resonance imaging with multiple inputs.

A linear time invariant model is applied to functional fMRI blood flow data. Based on traditional time series analysis, this model assumes that the fMRI stochastic output sequence can be determined by a constant plus a linear filter (hemodynamic response function) of several fixed deterministic inputs and an error term assumed stationary with zero mean. The input function consists of multiple exponential distributed (time delay between images) visual stimuli consisting of negative and erotic images. No a priori assumptions are made about the hemodynamic response function that, in essence, is calculated at each spatial position from the data. The sampling rate for the experiment is 400 ms in order to allow for filtering out higher frequencies associated with the cardiac rate. Since the statistical analysis is carried out in the Fourier domain, temporal correlation problems associated with inference in the time domain are avoided. This formal model easily lends itself to further development based on previously developed statistical techniques.

Risk factors for postoperative delirium in vascular surgery.

The aim of this study was to identify psychiatric and somatic risk factors associated with the development, severity and duration of postoperative delirium after vascular surgery. Forty-seven patients underwent aortic, carotid artery and peripheral artery surgery. Both, surgeon and psychiatrist, monitored patients preoperatively with daily follow up. Preoperative psychiatric assessment included standardized psychopathological scales for the detection of psychiatric symptoms and cognitive deficits. We diagnosed delirium using DSM IV criteria. Delirium Rating Scale was used to estimate delirium severity. Surgical parameters included patient history, diagnoses, medication and laboratory parameters. A statistical analysis was performed using multivariate regression analyses to find factors significantly associated with delirium development, severity, and duration. Thirty-six percent of the patients developed postoperative delirium after surgery. Comparison of different parameters revealed that especially preoperative depression symptoms and perioperative transfusions/infusions had significant predictive value for the development as well as for the severity of postoperative delirium.