University of Oregon and Good Samaritan Hospital, Portland, Oregon.
J Cogn Neurosci. 1989 Spring;1(2):136-52. doi: 10.1162/jocn.1989.1.2.136.
This study investigated the effects of different types of neurological deficits on timing functions. The performance of Parkinson, cerebellar, cortical, and peripheral neuropathy patients was compared to age-matched control subjects on two separate measures of timing functions. The first task involved the production of timed intervals in which the subjects attempted to maintain a simple rhythm. The second task measured the subjects' perceptual ability to discriminate between small differences in the duration of two intervals. The primacy of the cerebellum in timing functions was demonstrated by the finding that these were the only patients who showed a deficit in both the production and perception of timing tasks. The cerebellar group was found to have increased variability in performing rhythmic tapping and they were less accurate than the other groups in making perceptual discriminations regarding small differences in duration. Critically, this perceptual deficit appears to be specific to the perception of time since the cerebellar patients were unaffected in a control task measuring the perception of loudness. It is argued that the operation of a timing mechanism can be conceptualized as an isolable component of the motor control system. Furthermore, the results suggest that the domain of the cerebellar timing process is not limited to the motor system, but is employed by other perceptual and cognitive systems when temporally predictive computations are needed.
本研究探讨了不同类型的神经功能缺损对定时功能的影响。将帕金森病、小脑、皮质和周围神经病变患者的表现与年龄匹配的对照组在两个独立的定时功能测量上进行了比较。第一项任务涉及产生定时间隔，要求受试者试图保持简单的节奏。第二项任务测量了受试者区分两个间隔时长微小差异的感知能力。小脑在定时功能中的首要地位表现在这些患者在产生和感知定时任务方面都存在缺陷。小脑组在进行节奏敲击时表现出更大的变异性，并且在对时长微小差异进行感知辨别方面的准确性不如其他组。关键的是，这种感知缺陷似乎是特定于时间感知的，因为在测量响度感知的对照任务中，小脑患者没有受到影响。有人认为，定时机制的运作可以被概念化为运动控制系统的一个可分离的组成部分。此外，研究结果表明，小脑定时过程的领域不仅限于运动系统，而是在需要进行时间预测计算时被其他感知和认知系统所采用。
