Focussing on aging: an electrophysiological exploration of spatial and attentional processing during reading

Three types of selective attention tasks were presented to 24 young (20.5 years) and 24 middle-aged (57.5 years) participants. The major aim of the experiment was to explore three different aspects of selective attention, namely a pre-attentive level (i.e. auditory passive oddball task), an attentive level using spatial attention in a memory search task (i.e. selective search task) and an attentive level using a spatial cue to select a word in a reading-like situation (i.e. selective language task). The data showed that the mismatch negativity was not affected by aging although the ERPs indicated that the younger participants were paying more attention to the tones than the middle-aged. The selective search task data showed that spatial selective attention is only mildly affected by aging. The ERP-data seemed to indicate that irrelevant stimuli had a smaller impact in the middle-aged. The selective language data showed a look-a-like effect of flanker words for both age groups although the effect in the middle-aged was delayed by 30 ms and smaller. It was theorized that flankers might have smaller impact in the middle-aged. N400 was found to be smaller and delayed (90 ms) in the middle-aged participants. The overall conclusion on the basis of the three experiments is that the selectivity of processing was preserved or even enhanced in our particular group of middle-aged participants.