Onoe H, Komori M, Onoe K, Takechi H, Tsukada H, Watanabe Y
Department of Neuroscience, Osaka Bioscience Institute, Osaka, 565-0874, Japan.
Neuroimage. 2001 Jan;13(1):37-45. doi: 10.1006/nimg.2000.0670.
The presence of an "internal clock" in the brain has been assumed to underlie the information processing related to time. This clock plays a critical role in time keeping and time perception, which are closely associated with integrated functions in the brain. To identify the brain areas recruited for time keeping and time perception, we performed positron emission tomography (PET) studies with rhesus monkeys to measure regional cerebral blood flow (rCBF) as an index of neural activity during time discrimination tasks of different durations ranging from 400 to 1500 ms. Changes in rCBF that covaried significantly with the durations of the target being perceived by subjects were found in the dorsolateral prefrontal cortex (DLPFC), the posterior part of the inferior parietal cortex, basal ganglia, and posterior cingulate cortex. Furthermore, a loss of neuronal function in the DLPFC caused by a local application of bicuculline resulted in the selective reduction of performance in time discrimination tasks. The results indicate that a neural network composed of the posterior inferior parietal cortex to the DLPFC plays a crucial role in the temporal monitoring process in time perception.
大脑中“内部时钟”的存在被认为是与时间相关的信息处理的基础。这个时钟在计时和时间感知中起着关键作用，而计时和时间感知与大脑的整合功能密切相关。为了确定参与计时和时间感知的脑区，我们对恒河猴进行了正电子发射断层扫描（PET）研究，以测量区域脑血流（rCBF），作为在持续时间从400到1500毫秒不等的不同持续时间的时间辨别任务期间神经活动的指标。在背外侧前额叶皮层（DLPFC）、顶下叶皮层后部、基底神经节和后扣带回皮层中发现，rCBF的变化与受试者感知到的目标持续时间显著相关。此外，局部应用荷包牡丹碱导致DLPFC神经元功能丧失，导致时间辨别任务中的表现选择性降低。结果表明，由顶下叶后部皮层到DLPFC组成的神经网络在时间感知的时间监测过程中起着关键作用。
