Motion perception without explicit activity in areas MT and MST
Motion perception without explicit activity in areas MT and MST
复制标题
DOI：
10.1152/jn.01174.2003
复制
发表时间：
2004-09-01
影响因子：
2.5
通讯作者：
Churan, J
中科院分区：
文献类型：
--
作者：
Ilg, UJ;Churan, J
猕猴的中颞叶（MT）和中颞上皮层（MST）是处理视觉运动的重要区域。我们问，如果运动刺激由二阶运动刺激组成，这个假设是否成立。此外，我们询问MT区和MST区的神经元是否对移动声源进行编码。为了回答这些问题，我们训练了三只恒河猴辨别方向。在这项研究中，我们的猴子能够正确地报告所有运动刺激的方向。在任务执行过程中，记录脑中脑区（n = 38）和脑中脑区（n = 68）的定向选择性神经元的放电率。只有当运动刺激因亮度或闪烁而与背景分离时，这些神经元才会对刺激运动进行编码（傅立叶运动和漂移平衡运动）。如果这些分离线索不存在（在θ运动和移动声源的情况下），放电速率就不能编码刺激的方向。因此，我们得出的结论是，虽然颞叶和颞叶皮层无疑参与了对运动刺激的处理，但它们并不是负责感知运动刺激的最后皮层阶段。
It is widely accepted that middle temporal (MT) and middle superior temporal (MST) cortical areas in the brain of rhesus monkeys are essential for processing visual motion. We asked whether this assumption holds true if the moving stimulus consists of a second-order motion stimulus. In addition, we asked whether neurons in area MT and MST code for moving sound sources. To answer these questions, we trained three rhesus monkeys on a direction-discrimination task. Our monkeys were able to correctly report the direction of all motion stimuli used in this study. Firing rates of directionally selective neurons from area MT (n = 38) and MST ( n = 68) were recorded during task performance. These neurons coded only for the stimulus movement if the motion stimulus was separated from the background by luminance or flicker ( Fourier and drift-balanced motion). If these segregation cues were absent ( in the case of theta motion and of the moving sound source), firing rates did not code for the stimulus' direction. Therefore we conclude that although areas MT and MST are undoubtedly involved in processing a moving stimulus, they are not the final cortical stages responsible for perceiving it.