Explorations of individual differences relevant to high level skill.

Past research has uncovered few broad abilities that underlie high skill. In this paper, attempts to isolate three different abilities of potential relevance to skill are described. No evidence was found for a general time-sharing ability in common to different kinds of tasks. Modest evidence was found for a trait of attentional flexibility. That trait could potentially be of use in predicting success for skills that require rapid shifts of attention because of rapidly changing task demands. Finally, the rate of repetitive activity is correlated across different muscle groups. For example, finger tapping speed is correlated with foot tapping speed, suggesting a common rate limiting factor. In turn, those rates predict handwriting speed and, according to Book (1924), championship typing.