A componential analysis of pacemaker-counter timing systems.

Why does counting improve the accuracy of temporal judgments? P. R. Killeen and N. A. Weiss (see record 1988-12728-001) provided a formal answer to this question, and this article provides tests of their analysis. In Exps 1 and 2, a total of 20 college students responded on a telegraph key as they reproduced different intervals. Individual response rates remained constant for different target times, as predicted. The variance of reproductions was recovered from the weighted sum of the first and second movements of the component timing and counting processes. Variance in timing long intervals was mainly due to counting error, as predicted. In Exps 3–5, unconstrained response rate was measured and a total of 16 college students responded at (1) their unconstrained rate, (2) faster, or (3) slower. When Ss responded at the preferred rate, the accuracy of time judgment improved. Deviations in rates tended to increase the variability of temporal estimates. Implications for pacemaker-counter models of timing are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)