One of the most robust findings in cognitive functioning is that the elderly are more easily distracted by irrelevant information. This inhibition-deficit hypothesis may be useful in explaining older adults' deficits in visual search tasks. Treisman's Feature Integration Theory suggests that there are two ways to visually process information: parallel processing, an automatic process that does not require directed attention, and serial processing, which does. This study provides evidence for the role of inhibitory processes (and therefore frontal lobe involvement) in serial, but not parallel search. Six and ten year old children, undergraduate students, and elderly subjects participated in the experiment. Reaction times (RTs) were measured as subjects searched for a single target in one of three display types requiring serial, parallel, or both types of searches. The children and elderly's RTs were significantly longer compared to the undergraduate students. Non-significant trends were also seen in the conjunction condition. Children and elderly's RTs increased in the conjunction condition as the display size increased. Finally, elderly subjects showed faster RTs than the 6 year olds only. These results suggest a correlation between attention deficits and the development and degeneration of the frontal lobes.
Forbes '94, Stacy M., "Developmental Factors in Visual Search: The Inhibition Deficit Hypothesis in a Feature-Integration Task" (1994). Honors Projects. Paper 87.