Negative arousal amplifies the effects of saliency in short-term memory.

Evidence from 2 experiments suggests that negative arousal increases biases in attention that result from differences in visual salience. Participants were exposed to negative arousing or neutral sounds before briefly viewing an array of letters. They reported as many of the letters as they could, and attention was biased to certain letters by increasing salience through visual contrast. Regardless of the type of sound heard, participants were more likely to recall high-salience letters than low-salience letters. However, on arousing trials recall of high-salience letters increased, while recall of low-salience letters did not. These findings indicate that negative emotional arousal increases the selectivity of attention, and provides evidence for arousal-biased competition theory (Mather & Sutherland, 2011), which predicts that emotional arousal enhances representations of stimuli that have priority.