WMTを経験したラットの遅延調整課題における選択行動の検討

There are two forms of impulsivity: impulsive behavior and impulsive choice. The adjusting-delay task can measure both forms. Working memory ability is negatively correlated with impulsive choices. Working memory training in human drug-dependent participants further reduced impulsive choices than in the control group (Bickel, Yi, Landes, Hill, & Baxter, 2011). However, in male Long-Evans rats, there was no difference in impulsive choice between the working memory training group and the control group (Renda, Stein, & Madden, 2015). In the present study, we examined the effects of working memory training on impulsive choice in three male Wistar rats. The study consisted of three phases: pre-training, working memory training (WMT), and post-training. An adjusting-delay task was used for pre- and post-training, and the titrating-delay non-matching-to-position task was used for WMT. Despite the improvement in WMT performance, there was no difference in the mean adjusting delay between pre- and posttraining. Focusing on the number of delay time occurrences and the selection rate of larger-later reward lever, it was suggested that after WMT, choice behavior may be based on the length of the delay time. The results of this study may help establish a training method for controlling high impulsivity.