Anterior cingulate activation in high trait anxious subjects is related to altered error processing during decision making

BACKGROUND Individuals with high trait anxiety (HTA) can be studied to examine the effect of elevated levels of anxiety on the processing of stimuli and the selection of actions. The anterior cingulate cortex has been implicated in the detection and processing of errors. This investigation examined the hypothesis that HTA subjects are more sensitive to errors than nonanxious comparison subjects during a simple decision-making task and show increased activation in the anterior cingulate, particularly at low error rates. METHODS Thirteen HTA subjects were compared with 13 normal trait anxiety (NTA: 40th-60th percentile) subjects during functional magnetic resonance imaging while performing a two-choice prediction task at three different error rates. RESULTS Both HTA and NTA subjects performed similarly during a simple two-choice prediction task; however, during the low-error-rate condition, activation in the anterior cingulate and medial prefrontal cortex was significantly higher in HTA subjects and was correlated with trait but not state anxiety. CONCLUSIONS These results support the idea that HTA subjects devote more processing resources to decision making than do NTA subjects during times in which there is little chance of incorrect responding (i.e., the low-error-rate condition). The extent to which this altered activation within the anterior cingulate contributes to anxiety-proneness remains to be determined.