Contextual Factors and Age Group Differences in Coincidence-Anticipation Performance

Abstract

Age group differences in the direction of anticipatory motor responses may be attributable to the increased susceptibility of young children to contextual factors. That is, their performances on a given trial may be influenced by the stimulus speed presented in the previous trial. Mixed-sex groups of 8–9 year-olds and adults were given 3 blocks of 18 coincidence-anticipation trials each in a counterbalanced design. One block contained stimulus speeds of 1, 3, or 5 MPH, another speeds of 3, 5, or 7 MPH, and a third speeds of 5, 7, or 9 MPH, so that the 5 MPH speed was common to all blocks. An age group by sex by testing order by trial block ANOVA of constant error on the 5 MPH trials indicated that trial block was a significant factor within an age group by block interaction. Mean scores showed that the children responded very early in the 5–7–9 MPH block to the 5 MPH stimuli while the adults did not. Testing order was also a significant factor: subjects in the 1–3–5, 5–7–9, 3–5–7 MPH order performed with significantly greater directional error. While the later finding may indicate contextual factors influenced performance, there is no strong evidence that contextual factors differentially affected the age groups.

Key Words:

• coincidence-anticipation
• coincident timing
• children
• contextual factors
• bias effects
• age differences