Information processing and regional brain activity in anxiety and depression

Distinct patterns of resting regional electroencephalography (EEG) alpha activity have been reported in depressed and anxious individuals. Despite the high comorbidity of anxiety and depression, these patterns have seldom been compared within the same study. Furthermore, gender is seldom included as a factor in these studies. Depression is associated with differences in initiative to utilize strategies that improve memory performance (Hertel, 1998). Initiative and strategic use of information are strongly dependent on anterior brain regions, activity in which can be inferred from EEG alpha. To examine the relationship between brain activity and performance, regional alpha was obtained from depressed and non-depressed nonpatients during an emotional narrative processing task.; Replicating others, depressed participants showed poorer explicit memory performance. A distinct pattern of frontal brain activity in relation to memory performance emerged for each group. Good performance in non-depressed participants was associated with increased frontal, but not parietal, activity occurring in anticipation of narrative processing. In contrast, good performance in depressed participants was associated with increased frontal activity only during narrative presentation. These data suggest that performance disparities between depressed and non-depressed participants are related to differences in brain activity that reflect anticipatory involvement of anterior regions.; Resting eyes-closed regional EEG alpha was collected from four gender-balanced groups: depressed, anxious, comorbid (depressed and anxious), and control college students. More brain activity was observed over the left hemisphere. This asymmetry increased with anxiety. Low-depression/high-anxiety women showed greater left hemisphere activity. Gender was also involved in other significant interactions. Results indicate that regional brain activity in depression and anxiety differs for men and women, suggesting that gender distributions and degree of comorbidity can affect the outcome of a study. Current theorizing on the implications of distinct patterns of brain activity in depression and anxiety should take gender into consideration.