Abstract
We have examined how strategies for task performance change during the course of training in the memory-guided saccade task. The monkey was trained to make saccades to a target position (TP) which was determined by the color of the fixation point (FP). The task consisted of two kinds of trials; one representing those in early stages of learning [FP: green, TP: changed with experimental block: G trial] and the other representing those in well-learned stages [FP: white, TP: fixed through blocks: W trial]. After the monkey became abele to perform W trials with high success rate, saccades in G trials tended to direct to the TP for the W trial. In the present study, in order to further examine how the memory of the TP used in trials representing well-learned stages of learning affect the selection of the TP for saccades in the G trial, we introduced a new combination of the color and TP [FP: blue, TP: fixed through blocks: B trial] and examined the relationship between stages of learning in the B trial and the direction of saccades made in G trials. Saccades in G trials tended to direct to the TP for the B trial rather than the W trial while the success rate of the B trial was low. However, this tendency declined as this success rate reached a high level. These results suggest that the memory of the TP used in trials at stages where learning of the TP is in progress can be transferred to other similar types of trials, but that used in trials at well-learned stages can not be transferred. [Jpn J Physiol 54 Suppl:S191 (2004)]
