Competitive Selection and Age-related Changes in Visual Attention

Healthy aging entails selective losses in visual attention, including the ability to filter clutter, divide attention between inputs, and search for configurations or conjunctions of features. A model of attention as a competition to influence neurons in the visual brain provides a framework for understanding these effects. Under the model, competition is necessary to disambiguate neural responses and resolve object details when multiple stimuli fall within the same visual receptive fields. A pattern of perceptual interference between attended stimuli in close spatial proximity with one another appears to be a psychophysical marker of this competition. Studies of divided visual attention in young and older adults show pronounced age-related increases in the strength of spatial interference between attended items, but only in the presence of clutter. Results suggest that inefficient competition for selection contributes to older adults' visual attentional difficulties, compromising the ability to resolve details of multiple stimuli within small regions of the visual field. The conceptualization of attention as a competition for selection may thus provide a framework for understanding and assessing age-related attention losses.