Poster #: 99
Friday, Sep 11, 2015
Emotions attenuate the MMN elicited by changes in information rate
1Psychology, National University of Singapore, Singapore, Singapore
2National University of Singapore, Singapore, Singapore
Much evidence indicates that emotions influence time perception. To better understand this influence, we explored whether and how emotions alter sensitivity to changes in the speed or rate at which sounds unfold. A surprise and a neutral vocalization were compressed to 378 ms and expanded to 600 ms to create "fast" and "slow" stimuli, respectively. There were two blocks comprising surprise stimuli only and two blocks comprising neutral stimuli only. For one block of each condition, fast sounds were deviants and slow sounds were standards, and for the other block the standard and deviant assignment was reversed. Participants were instructed to ignore the sounds and to read personal material they had brought for the study. Event-related potentials relealed an influence of speed and emotion on the mismatch negativity (MMN). The MMN was larger in the slow than the fast condition and larger for neutral than surprise vocalizations. The speed effect suggests greater priority for a sudden decrease rather than an increase in information rate. The emotion effect suggests that emotions impair the pre-attentive monitoring of how events unfold in time.