Eye-hand coordination during reaching. II. An analysis of the relationships between visuomanual signals in parietal cortex and parieto-frontal association projections
Eye-hand coordination during reaching. II. An analysis of the relationships between visuomanual signals in parietal cortex and parieto-frontal association projections
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DOI：
10.1093/cercor/11.6.528
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发表时间：
2001-06-01
期刊：
影响因子：
3.7
通讯作者：
Caminiti, R
中科院分区：
文献类型：
--
作者：
Battaglia-Mayer, A;Ferraina, S;Caminiti, R
视觉-手信号在顶叶皮质的分布与顶-额叶投射之间的关系是本研究的主题。在PEC和V6A区进行单细胞记录，在那里也注射了不同的解剖示踪剂。这些猴子执行了各种行为任务，旨在研究壁细胞的视觉和运动特性，以及视网膜、眼睛和手相关信号对细胞活动的潜在组合。大多数细胞的活动与运动方向和手的活动位置有关。许多与REACH相关的细胞都受到眼部位置信息的影响。较少的细胞显示出与眼跳运动的关系。大多数神经元的活动与手部和眼部信号的组合有关。在准备手部运动的过程中，许多细胞也受到了调节。活动的明暗差异是常见的，并被解释为与视力和监测手部运动和/或视野中的位置有关。大多数被研究的细胞对运动的视觉刺激非常敏感，也对光流刺激有反应。视觉感受野一般较大，并延伸到视野的边缘。对于大多数神经元来说，在不同的时代和任务条件下计算的优先方向的方向聚集在一个有限的空间部分，即全局调整领域。这可以被认为是一个理想的框架，将空间上一致的与眼睛和手相关的信息结合起来，用于不同形式的视觉操作行为。所有这些性质都是PEC和V6A所共有的。视网膜、眼睛和手相关的活动类型，以及顶-额叶联系呼叫，周期性地分布在PEC和V6A区的切向区域。这些功能和解剖分布通过频谱和一致性分析进行了表征和比较，这揭示了活动类型和顶额连接之间存在选择性的“匹配”。这一匹配取决于每个单独的传出投射被处理的位置。本研究和配套研究的结果可能有助于对视性共济失调的重新解释，因为在顶神经元的全局调谐区域内，视网膜、眼睛和手相关的方向信号组合崩溃了。
The relationships between the distribution of visuomanual signals in parietal cortex and that of parieto-frontal projections are the subject of the present study. Single cell recording was performed in areas PEc and V6A, where different anatomical tracers were also injected. The monkeys performed a variety of behavioral tasks, aimed at studying the visual and motor properties of parietal cells, as well as the potential combination of retinal-, eye- and hand-related signals on cell activity. The activity of most cells was related to the direction of movement and the active position of the hand. Many of these reach-related cells were influenced by eye position information. Fewer cells displayed relationships to saccadic eye movements. The activity of most neurons related to a combination of both hand and eye signals. Many cells were also modulated during preparation for hand movement. Light-dark differences of activity were common and interpreted as related to the sight and monitoring of hand motion and/or position in the visual field. Most cells studied were very sensitive to moving visual stimuli and also responded to optic flow stimulation. Visual receptive fields were generally large and extended to the periphery of the visual field. For most neurons, the orientation of the preferred directions computed across different epochs and tasks conditions clustered within a limited sector of space, the field of global tuning. This can be regarded as an ideal frame to combine spatially congruent eye- and hand-related information for different forms of visuomanual behavior. All these properties were common to both PEc and V6A. Retinal, eye- and hand-related activity types, as well as parieto-frontal association calls, were distributed in a periodic fashion across the tangential domain of areas PEc and V6A. These functional and anatomical distributions were characterized and compared through a spectral and coherency analysis, which revealed the existence of a selective 'match' between activity types and parieto-frontal connections. This match depended on where each individual efferent projection was addressed. The results of the present and of the companion study can be relevant for a re-interpretation of optic ataxia as the consequence of the breakdown of the combination of retinal-, eye and hand-related directional signals within the global tuning fields of parietal neurons.