Matthew R. Sutherland

Arousal-biased competition in perception and memory

Our everyday surroundings besiege us with information. The battle is for a share of our limited attention and memory, with the brain selecting the winners and discarding the losers. Previous research shows that both bottom–up and top–down factors bias competition in favor of high priority stimuli. We propose that arousal during an event increases this bias both in perception and in long-term memory of the event. Arousal-biased competition theory provides specific predictions about when arousal will enhance memory for events and when it will impair it, which accounts for some puzzling contradictions in the emotional memory literature.

Disentangling the Effects of Arousal and Valence on Memory for Intrinsic Details

Kensinger (2009) and Mather (2007) both argue that intrinsic features of emotional items are remembered better than intrinsic features of non-emotional items. However, Kensinger attributes these effects to negative valence whereas Mather attributes them to arousal. In this paper, we note several reasons why arousal may be the driving factor even when a study reveals more detailed memory for negative items than for positive items. We also reanalyze previous data (Mather & Nesmith, 2008) to show that although both arousal and negative valence were correlated with memory accuracy, enhanced memory accuracy was accounted for by arousal rather than valence.

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.

Negative Arousal Increases the Effects of Stimulus Salience in Older Adults

Background/Study Context: Stimuli compete for mental representation, with salient stimuli attracting more attention than less salient stimuli. In a recent study, we found that presenting an emotionally negative arousing sound before briefly showing an array of letters with different levels of salience increased the reporting of the more salient letters but decreased reporting of the less salient letters (Sutherland & Mather, 2012, Emotion, 12, 1367–1372). In the current study we examined whether negative arousal produces similar effects on attention in older adults. Methods: Data from 55 older adults (61–80 years; M = 70.7, SD = 5.1) were compared with those from 110 younger adults (18–29 years; M = 20.3, SD = 2.3) from Sutherland and Mather (2012). Neutral or negative arousing sound clips were played before a brief presentation of eight letters, three of which were presented in a darker font than the others to create a group of high- and low-salience targets. Next, participants recalled as many of the letters as they could. At the end of the study, participants rated the emotional arousal and the valence of the sounds. Results: Higher ratings of emotional arousal for the sounds predicted a greater advantage for high-salience letters in recall. This influence of arousal did not significantly differ by age. Conclusion: The effects of negative arousal on subsequent attention were similar in older adults as in younger adults. Moreover, the results support arousal-biased competition theory (Mather & Sutherland, 2011, Perspectives on Psychological Science, 6, 114–133), which predicts that emotional arousal amplifies the effects of stimulus salience in attention and memory.

Perceptual Salience Does Not Influence Emotional Arousal's Impairing Effects on Top-Down Attention.

Emotional arousal impairs top-down attentional control while strengthening bottom-up attentional biases. In this study, we examined whether top-down impairments due to arousal can be modulated by increasing the perceptual salience of the target stimulus. To examine this question, we briefly displayed positive and negative arousing images prior to the encoding of 2 emotionally neutral items, 1 of which was to be remembered and 1 of which was perceptually salient (the to-be-remembered and the salient items were either the same item or different items). Eye tracking was used to measure attention biases during the encoding of the 2 competing neutral items, as well as to measure pupillary responses to the preceding modulator image. Viewing emotional images, regardless of valence, impaired top-down attention to animate stimulus targets (i.e., animals), regardless of perceptual salience. However, these effects on encoding had no influence on recognition memory. Taken together, these findings reveal that exposure to emotionally arousing images impairs top-down attention to animate stimuli, regardless of whether that stimulus is perceptually salient.

Arousal (but not valence) amplifies the impact of salience

ABSTRACT Previous findings indicate that negative arousal enhances bottom-up attention biases favouring perceptual salient stimuli over less salient stimuli. The current study tests whether those effects were driven by emotional arousal or by negative valence by comparing how well participants could identify visually presented letters after hearing either a negative arousing, positive arousing or neutral sound. On each trial, some letters were presented in a high contrast font and some in a low contrast font, creating a set of targets that differed in perceptual salience. Sounds rated as more emotionally arousing led to more identification of highly salient letters but not of less salient letters, whereas sounds’ valence ratings did not impact salience biases. Thus, arousal, rather than valence, is a key factor enhancing visual processing of perceptually salient targets.