Visual Search - Effects of Aging

Effects of Aging

There is a vast amount of research indicating that performance in conjunctive visual search tasks significantly improves during childhood and declines in later life. More specifically, young adults have been shown to have faster RT on conjunctive visual search tasks than both children and older adults, but their RTs were similar for feature visual search tasks. This suggests that there is something about the process of integrating visual features or serial searching that is difficult for children and older adults, but not for young adults. Studies have suggested numerous mechanisms involved in this difficulty in children including peripheral visual acuity, eye movement ability, ability of attentional focal movement, and the ability to divide visual attention among multiple objects.

Studies have suggested similar mechanisms for the difficulty of older adults such as age related optical changes that influence peripheral acuity, the ability to move attention over the visual field, the ability to disengage attention, and the ability to ignore distractors.

A study by Lorenzo-López, Amenedo, Pascual-Marqui, and Cadaveira in 2008 provides neurological evidence for the fact that older adults have slower RT during conjunctive searches compared to young adults. Event Related Potentials (ERP) showed longer latencies and lower amplitudes in older subjects than young adults at the P3 component, which is related to activity of the parietal lobes. This suggests the involvement of the parietal lobe function with an age-related decline in the speed of visual search tasks. Results also showed that older adults, when compared to young adults, had significantly less activity in the anterior cingulate cortex and many limbic and occipitotemporal regions that are involved in performing visual search tasks.