Fattori P, Gamberini M, Kutz D F, Galletti C
Dipartimento di Fisiologia umana e generale, Università di Bologna, Piazza di Porta S. Donato 2, 40127, Bologna, Italy.
Eur J Neurosci. 2001 Jun;13(12):2309-13. doi: 10.1046/j.0953-816x.2001.01618.x.
In previous experiments we have found that several cells of area V6A in the macaque superior parietal lobule were activated by small and stereotyped movements of the arms (C. Galletti, P. Fattori, D. F. Kutz & P. P. Battaglini, Eur. J. Neurosci., 1997, 9, 410). This behaviour was not accounted for by retinal information, nor by somatosensory inputs from the arms. We now want to investigate whether V6A neurons are modulated by purposeful movements aimed at reaching visual targets or targets located outside the field of view. V6A neuronal activity was collected while monkeys performed arm movements during an instructed-delay reaching task in darkness. The task required the animal to reach out for a visual target in the peripersonal space and to bring the hand back to its body. Quantitative analysis of neuronal activity carried out on 55 V6A neurons showed that: (i) the great majority of neurons (71%) was significantly modulated during the execution of arm movements; (ii) 30% of neurons were significantly modulated during preparation of reaching; and (iii) modulations during both execution and preparation of reaching occurred in the absence of any visual feedback and were not due to eye movements. V6A reach-related neurons could be useful in guiding the hand to reach its target with or without visual feedback.
在之前的实验中，我们发现猕猴顶上小叶V6A区的几个细胞会被手臂的微小且模式化的动作激活（C. 加莱蒂、P. 法托里、D. F. 库茨和P. P. 巴塔格利尼，《欧洲神经科学杂志》，1997年，第9卷，第410页）。这种行为既不能用视网膜信息来解释，也不能用来自手臂的体感输入来解释。我们现在想要研究V6A神经元是否会受到旨在触及视觉目标或视野外目标的有目的动作的调节。在猴子于黑暗中执行指令延迟伸手任务期间进行手臂动作时，收集了V6A神经元的活动。该任务要求动物伸手去够个人空间周边的视觉目标并将手放回身体。对55个V6A神经元的神经元活动进行的定量分析表明：（i）绝大多数神经元（71%）在手臂动作执行期间受到显著调节；（ii）30%的神经元在伸手准备期间受到显著调节；（iii）在伸手执行和准备期间的调节在没有任何视觉反馈的情况下发生，且不是由眼球运动引起的。与V6A伸手相关的神经元在有或没有视觉反馈的情况下都可能有助于引导手触及目标。
