Onoda Keiichi, Takahashi Erika, Sakata Shogo
Graduate School of Biosphere Science, Hiroshima University, Higashi-Hiroshima, 739-8521, Japan.
Brain Res Cogn Brain Res. 2003 Jul;17(2):380-7. doi: 10.1016/s0926-6410(03)00139-3.
The purpose of this study was to evaluate the roles of the frontal cortex, hippocampus, and cerebellum in timing and time perception using event-related potentials (ERPs) in rats. Rats were trained to discriminate between 2-s and 8-s auditory signal durations using a choice procedure. A simple reaction-time task using only the 2-s signal served as the control condition. In both tasks, ERPs were computed at stimulus onset and offset. Auditory ERPs were recorded from the frontal cortex, hippocampus, and cerebellum. The stimulus onset ERPs consisted of P2, N2, and P3-like components. Significantly greater amplitudes of the P3-like components were observed during the temporal-discrimination task when compared to the simple reaction-time task. At the stimulus offset, P2, N2, and P3-like components were elicited as well as the stimulus onset. Only in the frontal cortex was the P3-like component that appeared at the stimulus offset larger for the temporal-discrimination task than for the simple reaction-time task. These results suggest that the frontal cortex, hippocampus, and cerebellum contribute to interval timing in the seconds range.
本研究的目的是利用大鼠的事件相关电位（ERP）评估额叶皮质、海马体和小脑在计时和时间感知中的作用。使用选择程序训练大鼠区分2秒和8秒的听觉信号持续时间。仅使用2秒信号的简单反应时任务作为对照条件。在这两个任务中，ERP均在刺激开始和结束时计算。从额叶皮质、海马体和小脑记录听觉ERP。刺激开始时的ERP由P2、N2和类似P3的成分组成。与简单反应时任务相比，在时间辨别任务中观察到类似P3成分的幅度明显更大。在刺激结束时，与刺激开始时一样，也诱发了P2、N2和类似P3的成分。仅在额叶皮质中，时间辨别任务中刺激结束时出现的类似P3成分比简单反应时任务中的更大。这些结果表明，额叶皮质、海马体和小脑在秒级的间隔计时中发挥作用。
