Abstract
Human adults appear to take their sensory and motor uncertainty into account in order to maximize gain in visuomotor decision tasks that pose challenges similar to those involved in catching a rapidly approaching ball or reaching for an object while avoiding another. How this ability develops is currently not known, but it is possible that immature visuomotor decision-making with respect to risks can help explain the high rate of childhood accidents. To explore the development of visuomotor decision making under risk, we applied a recently proposed economic decision making framework that describes adults’ behavior in a rapid pointing task (Trommershäuser et al., 2003) to a child-friendly version of the same task. We asked 6 to 11-year old children and adults to earn points by rapidly touching a target on a screen, while avoiding a partially overlapping penalty region. Values assigned to penalty and target regions and spatial configurations of those regions were varied. To correctly choose the aiming point that maximizes gain for each condition, subjects must combine information about the reward structure with information about their own visuomotor uncertainty. In line with previous findings, adults chose movement strategies that came close to maximizing expected gain in response to changes in penalty location and size. Children, however, showed a change in strategy when risk was introduced but their pointing strategies were less close to optimal than those of adults. We used two control tasks to check that children’s performance was not confounded by either non-linear understanding of numeric value or poor knowledge of own motor variability. Our findings suggest that the ability to take visuomotor uncertainty into account when maximizing gain in a rapid visuomotor task takes a surprisingly long time to develop, and continues to mature until after age 11 years.
Meeting abstract presented at VSS 2012