Sex differences in processing aggression words using the Emotional Stroop task

Abstract

There is a robust relationship between the salience of stimulus materials presented in the Emotional Stroop task and inhibition of response in clinical populations. Researchers have now found information-processing biases in both forensic and non-forensic samples presented with threatening or aggressive stimuli [Cohen et al., 1998; Eckhardt and Cohen, 1997; Smith and Waterman, 2003; Van Honk et al., 2001]. We sought to explore sex differences in processing words relating to acts of direct and indirect aggression using a group of undergraduates (50 males and 50 females). Participants also completed self-report questionnaires (AQ and EXPAGG) to allow some consideration of the relationship between objective and subjective measures. We predicted that males would demonstrate delayed responses when presented with words relating to acts of direct aggression. We also predicted that high levels of physical aggression would be the best predictor of bias for direct aggression words, high levels of verbal aggression would be the best predictor of bias for indirect aggression words, physical aggression would predict bias in males, and verbal aggression would predict bias in females. Males demonstrated a perceptual bias for words relating to acts of direct aggression, taking significantly longer to correctly colour name direct aggression words. Females were slower to correctly colour name indirect aggression words, but not significantly so. Verbal aggression, as expected, predicted bias performance for indirect aggression words but anger rather than physical aggression was the best predictor of bias for direct aggression words. Gender was a predictor for bias with both sets of words. Contrary to our predictions, it was observed that a high level of physical aggression was the best predictor of bias in both males and females. These data provide further evidence to confirm the saliency of aggression words to aggressive individuals in non-forensic populations.