Center for Neuroscience Imaging Research, Institute for Basic Science (IBS), Suwon 16419, Republic of Korea.
Department of Neuroscience, Washington University School of Medicine, St. Louis, MO 63110, United States of America.
Sci Adv. 2023 Jul 7;9(27):eadg4156. doi: 10.1126/sciadv.adg4156.
Prior knowledge facilitates our perception and goal-directed behaviors, particularly when sensory input is lacking or noisy. However, the neural mechanisms underlying the improvement in sensorimotor behavior by prior expectations remain unknown. In this study, we examine the neural activity in the middle temporal (MT) area of visual cortex while monkeys perform a smooth pursuit eye movement task with prior expectation of the visual target's motion direction. Prior expectations discriminately reduce the MT neural responses depending on their preferred directions, when the sensory evidence is weak. This response reduction effectively sharpens neural population direction tuning. Simulations with a realistic MT population demonstrate that sharpening the tuning can explain the biases and variabilities in smooth pursuit, suggesting that neural computations in the sensory area alone can underpin the integration of prior knowledge and sensory evidence. State-space analysis further supports this by revealing neural signals of prior expectations in the MT population activity that correlate with behavioral changes.
先前知识促进了我们的感知和目标导向行为，尤其是在感官输入不足或存在噪声时。然而，先前期望改善感觉运动行为的神经机制尚不清楚。在这项研究中，当猴子执行带有视觉目标运动方向的先前预期的平滑追踪眼动任务时，我们观察了视觉皮层中颞中（MT）区的神经活动。当感觉证据较弱时，先前的期望会根据其偏爱的方向有区别地减少 MT 神经反应。这种反应的减少有效地锐化了神经群体方向调谐。使用现实的 MT 群体模拟表明，调谐的锐化可以解释平滑追踪中的偏差和可变性，这表明仅在感觉区域中的神经计算就可以支持先前知识和感觉证据的整合。状态空间分析通过揭示与行为变化相关的 MT 群体活动中的先前期望的神经信号进一步支持了这一点。
