FIG. 5.

Normalized weights for 16-click trains. Plotted weights are the mean of four subjects per condition, with each panel showing data for a single value of ICI. Error bars indicate means of normalized 95% confidence intervals (see the Appendix), as in Fig. 3. Dashed lines indicate equal weights for all clicks. At short ICI, the results show a significant increase in the weight for click 1 relative to the remaining weights, while weights are approximately even for longer ICIs. The increase is not accompanied by monotonically decreasing weights for clicks following the first, as in the relative effectiveness of individual clicks estimated by Hafter and Buell (1990) [dotted lines, from Eq. (2) fit with k equal to 0.85, 0.91, 0.89, and 0.63 for ICIs of 14, 8, 5, and 3 ms, respectively]. Rather, suppression of the weights for later clicks seems to be rather abrupt. Additionally, there is a tendency for weights to recover over the duration of the stimulus, resulting in somewhat elevated weights toward the stimulus offset.