Duhamel J R, Colby C L, Goldberg M E
Laboratory of Sensorimotor Research, National Eye Institute, Bethesda, Maryland 20892, USA.
J Neurophysiol. 1998 Jan;79(1):126-36. doi: 10.1152/jn.1998.79.1.126.
In a previous report, we described the visual response properties in the ventral intraparietal area (area VIP) of the awake macaque. Here we describe the somatosensory response properties in area VIP and the patterns of correspondence between the responses of single neurons to independently administered tactile and visual stimulation. VIP neurons responded to visual stimulation only or to visual and tactile stimulation. Of 218 neurons tested, 153 (70%) were bimodal in the sense that they responded to stimuli that were independently applied in either sensory modality. Unimodal visual and bimodal neurons were intermingled within the recording area and could not be distinguished on the basis of their visual response properties alone. Most of the cells with a tactile receptive field (RF) responded well to light touch or air puffs. The distribution of RF locations principally emphasized the head (85%), with approximately equivalent representations of the upper and lower face areas. The tactile and visual RFs were aligned in a congruent manner, with the intersection of the visual vertical and horizontal meridian having its tactile counterpart in the nose/mouth area. Small foveal visual RFs were paired with small tactile RFs on the muzzle, and peripheral visual RFs were associated with tactile RFs on the side of the head or body. Most cells showed a strong sensitivity to moving stimuli, and the preferred directions of visual and tactile motion coincided in 85% of bimodal cells. In some cases, bimodal responses patterns were complementary: cells responding to motion in depth toward the monkey had responses, whereas cells responding to motion in depth away form the monkey had responses. Other forms of bimodal response congruence included orientation selectivity, and , , and / response types. The large proportion of bimodal tactile and visual neurons with congruent response properties in area VIP indicates that there are important functional differences between area VIP and other dorsal stream areas involved in the analysis of motion. We suggest that VIP is involved in the construction of a multisensory, head-centered representation of near extrapersonal space.
在之前的一份报告中，我们描述了清醒猕猴腹侧顶内区（VIP区）的视觉反应特性。在此，我们描述VIP区的体感反应特性以及单个神经元对独立施加的触觉和视觉刺激的反应对应模式。VIP神经元对仅视觉刺激或视觉和触觉刺激均有反应。在测试的218个神经元中，153个（70%）是双峰的，即它们对独立施加于任一感觉模态的刺激均有反应。单峰视觉神经元和双峰神经元在记录区域内相互交织，无法仅根据其视觉反应特性进行区分。大多数具有触觉感受野（RF）的细胞对轻触或吹气反应良好。RF位置的分布主要集中在头部（85%），上、下脸部区域的表征大致相当。触觉和视觉RF以一致的方式对齐，视觉垂直和水平子午线的交点在鼻/口区域有其触觉对应点。小中央凹视觉RF与口鼻部的小触觉RF配对，周边视觉RF与头部或身体侧面的触觉RF相关联。大多数细胞对移动刺激表现出强烈的敏感性，并且在85%的双峰细胞中，视觉和触觉运动的偏好方向一致。在某些情况下，双峰反应模式是互补的：对朝着猴子深度运动有反应的细胞，而对远离猴子深度运动有反应的细胞。双峰反应一致性的其他形式包括方向选择性，以及 ， ，和 / 反应类型。VIP区中具有一致反应特性的双峰触觉和视觉神经元的比例很大，这表明VIP区与参与运动分析的其他背侧流区域之间存在重要的功能差异。我们认为VIP区参与了近个人空间的多感觉、以头部为中心的表征构建。
