University of Pennsylvania Medical Center Philadelphia, PA, USA.
Front Integr Neurosci. 2011 Oct 4;5:59. doi: 10.3389/fnint.2011.00059. eCollection 2011.
We used voxel-based lesion-symptom mapping (VLSM) to determine which brain areas are necessary for discriminating time intervals above and below 1 s. VLSM compares behavioral scores of patients that have damage to a given voxel to those that do not on a voxel-by-voxel basis to determine which voxels are critical for the given behavior. Forty-seven subjects with unilateral hemispheric lesions performed a temporal discrimination task in which a standard stimulus was compared on each trial to a test stimulus. In different blocks of trials, standard stimuli were either 600 or 2000 ms. Behavioral measures included the point of subjective equality, a measure of accuracy, and the coefficient of variation, a measure of variability. Lesions of the right middle and inferior frontal gyri were associated with decrements in performance on both durations. In addition, lesions of the left temporal lobe and right precentral gyrus were associated exclusively with impaired performance for subsecond stimuli. In line with results from other studies, these data suggest that different circuits are necessary for timing intervals in these ranges, and that right frontal areas are particularly important to timing.
我们使用基于体素的病变-症状映射（VLSM）来确定区分 1 秒以上和以下时间间隔所需的大脑区域。VLSM 比较了具有给定体素损伤的患者的行为评分与该体素上没有损伤的患者的行为评分，以确定哪些体素对给定行为至关重要。47 名单侧半球损伤的受试者进行了一项时间辨别任务，在该任务中，每个试验将标准刺激与测试刺激进行比较。在不同的试验块中，标准刺激分别为 600 或 2000 毫秒。行为测量包括主观均等点，准确性的度量，以及变异系数，即变异性的度量。右中额和下额回的损伤与两种持续时间的表现下降有关。此外，左颞叶和右中央前回的损伤仅与亚秒刺激的表现受损有关。与其他研究的结果一致，这些数据表明，不同的回路对于这些范围内的时间间隔是必要的，并且右额区对时间特别重要。
