Department of Neuroscience, Georgetown University Medical Center, Washington, District of Columbia.
J Neurophysiol. 2014 Apr;111(8):1671-85. doi: 10.1152/jn.00436.2013. Epub 2014 Feb 5.
The respective roles of ventral and dorsal cortical processing streams are still under discussion in both vision and audition. We characterized neural responses in the caudal auditory belt cortex, an early dorsal stream region of the macaque. We found fast neural responses with elevated temporal precision as well as neurons selective to sound location. These populations were partly segregated: Neurons in a caudomedial area more precisely followed temporal stimulus structure but were less selective to spatial location. Response latencies in this area were even shorter than in primary auditory cortex. Neurons in a caudolateral area showed higher selectivity for sound source azimuth and elevation, but responses were slower and matching to temporal sound structure was poorer. In contrast to the primary area and other regions studied previously, latencies in the caudal belt neurons were not negatively correlated with best frequency. Our results suggest that two functional substreams may exist within the auditory dorsal stream.
腹侧和背侧皮质处理流各自的作用在视觉和听觉领域仍在讨论中。我们描述了猕猴的听觉后带皮层（初级背侧流区域的一个后部区域）中的神经反应。我们发现了具有更高时间精度的快速神经反应以及对声音位置有选择性的神经元。这些群体部分分离：在一个尾内侧区域的神经元更精确地跟随时间刺激结构，但对空间位置的选择性较小。该区域的反应潜伏期甚至比初级听觉皮层更短。在一个尾外侧区域的神经元对声源方位和仰角具有更高的选择性，但反应较慢，与时间声音结构的匹配较差。与初级区域和之前研究的其他区域相比，后带神经元的潜伏期与最佳频率没有负相关。我们的结果表明，听觉背侧流中可能存在两个功能子流。
