Age and the ability to inhibit distractor information in visual selective attention.

Adult age differences in the effects of different types of distractor interference on visual search were examined. Young adults (mean age = 18.5 years) and older adults (mean age = 69.5 years) performed a target-counting task that required a complete search of a visual display in each trial. Varying numbers of targets were presented alone in displays or were interspersed among eight distractor items that were either categorically related (letters) or conceptually related (numbers representing either the correct number or the incorrect number of targets in the display) to the target item (letter Q). An adult age difference in the speed of target enumeration was observed when targets were presented alone in the display. In addition, when targets appeared with distractors, both younger and older adults were penalized more by conceptually interfering distracters than by categorically related distractors. Results did not suggest an age-related decline in inhibitory processes.