Functional role of association fibres for a visual association area: The posterior suprasylvian sulcus of the cat
Functional role of association fibres for a visual association area: The posterior suprasylvian sulcus of the cat
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视觉关联区域关联纤维的功能作用：猫的外侧裂上沟
DOI：
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发表时间：
2004
影响因子：
2
通讯作者：
O. Creutzfeldt
中科院分区：
文献类型：
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作者：
R. Guedes;Satoru Watanabe;O. Creutzfeldt
本文报道了17/18区联合纤维向后上丘脑皮层(PSSC)分离的实验研究。在对照实验中，所有神经元在中央5-10°视野内都有较大的感受野，没有详细的视网膜复制。在PSSC内侧银行，感受野位于对侧视野，而在外侧银行，神经元的感受野位于同侧。电刺激同侧枕内侧17/18区交界处可兴奋PSSC内的神经元。发布、分析、更新。)和外侧膝状体。大约2/3的神经元可以从所有这些区域兴奋，尽管潜伏期各不相同。急性和慢性切断同侧17/18区中央5~10°的软膜下表达后，PSSC神经元的视觉反应特性，包括方向敏感度、感受野大小和眼力，均无明显改变。在整个对侧视皮层(包括PSSC和对侧Clare-Bishop区的大片区域)消融后，来自同侧眼睛的输入显著减少，但其他反应特性没有显著变化。这些基本否定的发现与其他作者的不同发现相联系进行了讨论，有人认为，只有中央视野的软膜下切开可能防止了同侧冈上皮质及其传入的损害，如果通过吸引消融整个区域17，这是很难避免的。有人提出，联合纤维可能只“非特异性地”兴奋相关联合区域的神经元，而不是将特定的反应特征强加给它们。后者也起源于关联区，主要来源于丘脑传入和皮质内相互作用。
SummaryThis paper reports on experiments in which the effect of disconnexion of association fibres from Area 17/18 to the posterior suprasylvian cortex (PSSC) was investigated. In the control experiments, all neurons had large receptive fields in the central 5–10 ° of the visual field without detailled retinotopy. In the medial bank of PSSC, receptive fields were located in the contralateral visual field, while receptive fields of neurons in the lateral bank were located ipsilaterally. Neurons in PSSC could be excited by electrical stimulation of the ipsilateral Area 17/18 boundary, of the medial pulvinar (N. lat. post., pars, lat.) and the lateral geniculate body. About 2/3 of all neurons could be excited from all these regions, although with varying latencies. After acute and chronic subpial undercutting of the representation of the central 5–10 ° of the ipsilateral area 17/18, visual response properties including direction sensitivity, receptive field size and ocularity of PSSC-neurons in the medio-posterior bank did not change significantly. After ablation of the whole contralateral visual cortex (including PSSC and a wide region of the contralateral Clare-Bishop area) the input from the ipsilateral eye was considerably diminished, but other response properties did not change significantly. These essentially negative findings are discussed in relation to different findings of other authors, and it is argued that the subpial undercutting of only the central visual field representation may have prevented damage to the ipsilateral suprasylvian cortex and its afferents, which is difficult to avoid if the whole area 17 is ablated by suction. It is proposed, that association fibres may only “unspecifically” excite neurons in related association areas rather than impose onto them specific response features. These latter are derived, also in association areas, essentially from their thalamic afferents and their intracortical interaction.