Preparing fingers within and between hands: Examining the maximal preparation benefit in older age

Previous research has demonstrated an age-related deficit in the preparation of finger responses. A key question is whether the age-related deficit reflects differences in speed of preparation or differences in the maximal preparation benefit that can be attained given sufficiently long preparation intervals. The present study examined this issue by asking a group of younger and older adults to perform the finger-cueing task with four, relatively long, preparation intervals that varied randomly across trials. Reaction time results demonstrated that older adults were deficient in preparing two fingers on two hands at the two shortest preparation intervals, but not at the two longest ones. This outcome suggests that, with randomised preparation intervals, older adults require more time than younger adults to achieve the maximal level of between-hands preparation.