应用常规电生理技术,研究SD大鼠皮层听-视多感觉神经元的分布和听-视信息整合.共记录到130个听-视双模态神经元,其中65个A-V型神经元,28个v-A型神经元和37个a-V型神经元.这些双模态神经元主要分布于听区的背侧,听皮层和视皮层的交界处,具有明显的区域性,呈条带状分布,v-A型神经元较多地位于近听皮层一侧,a-V型神经元则主要位于近视皮层一侧,A-V型神经元位于两者之间.在条带中,双模态神经元分布不均一,有片状分布趋势.双模态神经元的听.视信息整合效应分为增强型、抑制型和调制型.整合效应与声.光组合刺激的时间间隔有关,其中75%的神经元获得最大整合效应的时间间隔在30~50ms之间.研究结果提示,大鼠皮层存在听.视多感觉神经元分布区,这些神经元遵循存在于其他动物相关脑区多感觉信息整合规律,参与听.视感觉信息整合.
Conventional electrophysiological technique was used to determine the distribution of auditory-visual multisensory neurons and to study the auditory-visual information integration in rat cortex. 130 auditory-visual bimodal neurons including 65 A-V neurons, 28 v-A neurons and 37 a-A neurons were isolated. These bimodal neurons located in the boundary area between auditory and visual cortex were mainly in the dorsal bank of auditory cortex. There are divided strip trends in the distribution of different types of bimodal neurons that most of v-A neurons were recorded in the cortex close to auditory cortex, a-V neurons were mostly appeared in the part adjacent to visual cortex and a majority of A-V neurons were between of them. One point must be pointed out that bimodal neurons were presented not uniformly but in the way of patchy distribution. According to the different integration effects, all bimodal neurons were divided into three types: enhancement, modulation and depression. The temporal disparity among combinations of two stimuli was showed to be a critical factor influencing the integration of auditory and visual information. At the same time the best interstimulus interval time under which the strongest interaction can be evoked has been thoroughly studied and found that it has somewhat regular arrangement that 98 of the 130 (75%) auditory-visual bimodal neurons in this experiment have the best integration among the 30~50 ms interval time. The results suggest that the auditory-visual bimodal neurons exist in the rat cortex having the similar multisensory and auditory-visual integration characteristics of the multimodal neurons in the other animals' analogy cortex.