In studies of attention in visual search, older adults consistently perform more poorly than young adults. In most visual attention computer tasks, simple, conjunction, and unconfounded trials are presented randomly. This study explores the possibility that older adults are slower than young adults at changing their search strategies to match each type of trial. If this is the case, blocking the trials together so that the subject sees a series of each type of trial should allow the older adults to perfect their search strategies, giving them reaction times similar to those of young adults. In this experiment, 14 young adults (mean age 18.6 years) and 5 older adults (mean age 68.6 years) were asked to perform a blocked computer search task. The results were then compared to a study performed last year. The results showed that blocking the trials significantly lowered the reaction times of older adults, but did not effect the reaction times of young adults.
Lewandowski '96, Kristen, "The Effects of Blocking on Selective Attention in Visual Search" (1996). Honors Projects. Paper 74.