Windows to Functional Decline: Naturalistic Eye Movements in Older and Younger Adults

Subtle changes in everyday tasks precede and predict future disability in older adults. Eye tracking may provide a sensitive tool for detecting subtle disruption of everyday task performance and informing the mechanism(s) of breakdown. We tracked eye movements of healthy older adults (OA, n = 24) and younger adults (YA, n = 25) while they passively viewed a naturalistic scene (Passive Viewing condition) and then verbally reported the necessary steps for achieving a task goal (e.g., pack a lunch; Verbalize Goal condition). Participants also completed a performance-based task of packing a lunch using real objects as well as neuropsychological tests. Group (young vs. old) by Condition (Passive Viewing vs. Verbalize Goal) ANOVAs were conducted to analyze eye tracking variables (i.e., fixation rate, number/duration of fixations to target/distractor objects and off objects). Both the younger and older adults made significantly fewer fixations to distractors during Verbalize Goal than Passive Viewing. Also, significant Group X Condition interactions were observed, indicating that younger adults, but not older adults, spent significantly more time viewing targets and less time off-objects in the goal driven, Verbalize Goal condition than the Passive Viewing condition. Goal-directed eye movements correlated with everyday action errors and tests of executive functioning. Taken together, results support theories of age-related decline in top-down cognitive control and indicate the potential utility of this eye tracking paradigm in detecting subtle age-related functional changes.