S141 Aging and automatic detection of deviancy in vision: Event-related potential studies

Objectives We investigated the possibility of age-related differences in automatic visual change detection. It is well-established that efficiency of various kinds of attentional processes decreases in elderly, but our knowledge on the field of automatic information processing is limited. Methods Visual mismatch negativity (vMNN) component of event-related brain activity was investigated in three experiments. Using checkerboard stimuli we developed a method capable of quick assessment of vMMN. In a new paradigm with offset responses we controlled low-level adaptation processes, and in the third experiment we investigated the possibility of age-related change in visual persistence. Results Early phase of vMMN was preserved in the older group. However, in a later range of vMMN we obtained decreased amplitude in elderly. In the older group vMMN indicated a longer perceptual persistence. Discussion Automatic detection of environmental change is preserved in older age, but evaluation of the changing stimulation become less efficient. The increased persistence is a sign of compromised temporal acuity in the older sample. Conclusion Like in the field of attentive visual processing, we obtained event-related brain electric activity changes in the domain of automatic perceptual processing. Significance VMMN seems to be a proper method for assessing compromised visual processing in “healthy” aging, and the results open a possibility for investigating various pathological conditions frequently present in aged populations.