Matell Matthew S, Portugal George S
Department of Psychology, Villanova University, 800 Lancaster Avenue, Villanova, PA 19085, United States.
Behav Processes. 2007 Feb 22;74(2):198-208. doi: 10.1016/j.beproc.2006.08.009. Epub 2006 Oct 4.
The pattern of responding on a peak-interval timing task allows one to make inferences regarding the sources of variation that contribute to interval timing behavior. Non-temporal factors such as impulsivity may impact the validity of these inferences. Rats were trained on a 15s peak-interval procedure (PI) or a mixed 15s behaviorally dependent variable-interval, 15s peak-interval procedure (bdVIPI) for an extended number of sessions. Extended training on the PI revealed a bi-modal distribution in the times at which subjects started responding for temporally predictable reinforcement, suggesting that multiple processes contribute to the behavioral pattern obtained in this procedure. Training on the bdVIPI eliminated the early mode of this bi-modal distribution, thereby decreasing the variation in start times. These results suggest that alternative response options can modulate the influence of impulsivity in timing tasks.
在峰值间隔计时任务中的反应模式使人们能够对导致间隔计时行为的变异来源进行推断。诸如冲动性等非时间因素可能会影响这些推断的有效性。大鼠接受了15秒峰值间隔程序(PI)或混合的15秒行为依赖可变间隔、15秒峰值间隔程序(bdVIPI)的训练,训练次数较多。对PI的长期训练显示,在受试者开始对时间上可预测的强化做出反应的时间上呈现双峰分布,这表明多个过程促成了在此程序中获得的行为模式。对bdVIPI的训练消除了这种双峰分布的早期模式,从而减少了开始时间的变异。这些结果表明,替代反应选项可以调节冲动性在计时任务中的影响。