How arousal modulates memory: disentangling the effects of attention and retention.

Emotion may influence memory both by altering attention and perception during encoding and by affecting memory retention. To date, studies have focused on the enhancement of memory consolidation by arousal. However, they have failed to rule out a role for attention. To specifically link memory enhancement of arousing material to modulation of memory retention, we examined recognition of neutral and arousing words at two time points and under conditions that manipulate attention during encoding. Participants were briefly presented with an arousing or neutral word at the periphery, while fixating on a central word. Recognition of peripheral words was assessed either immediately or after 24 h. Whereas recognition of neutral words became worse over time, recognition of arousing words remained the same and was better than neutral word recognition at delay. The results indicate that arousal supports slower forgetting even when the difference in attentional resources allocated to stimuli is minimized.