Abstract
Healthy aging is associated with changes in multiple aspects of motor control and cognition. Specifically, older adults have been found to be excessively risk-averse in economic decision-making tasks, and less efficient and more dependent on visual feedback when executing rapid movements. In the present study we investigated the performance of younger (N=52, age 18-30) and older (N=34, age 62-77) adults in the aiming-under-risk task, which constitutes the motor analogue of a gambling task, and in which younger adults are known to be close to optimal. In each trial, the observers had to tap their index finger on a touch screen before a time deadline which was individually titrated. They tried to hit a target area, which was associated with monetary gains, while avoiding a nearby or partially overlapping penalty area, which was associated with variable money losses. The results indicated that older adults were as efficient as younger adults, both groups scoring at on average over 90% of the gains expected from an optimal observer. Their strategies however differed. Younger adults tended to adjust their aiming points to avoid the penalty area slightly less than expected from an optimal participant, whereas the older adults showed a tendency for overadjustment. A model-based analysis of the aiming points as a function of penalty value, distance between penalty and target areas and observer precision, showed that the older adults´ strategy was compatible with a relative increase of the value attributed to losses relative to gains, compared to younger adults. Individual precision instead was not differently estimated by the members of the two groups. Overall, the results suggest that older adults are more risk-averse than younger adults in the aiming-under-risk task, similar to what has been shown for economic decision-making. At the same time, the change in strategy does not necessarily cause suboptimal performance.
Meeting abstract presented at VSS 2017