Goard Michael J, Pho Gerald N, Woodson Jonathan, Sur Mriganka
Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States.
Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, United States.
Elife. 2016 Aug 4;5:e13764. doi: 10.7554/eLife.13764.
Mapping specific sensory features to future motor actions is a crucial capability of mammalian nervous systems. We investigated the role of visual (V1), posterior parietal (PPC), and frontal motor (fMC) cortices for sensorimotor mapping in mice during performance of a memory-guided visual discrimination task. Large-scale calcium imaging revealed that V1, PPC, and fMC neurons exhibited heterogeneous responses spanning all task epochs (stimulus, delay, response). Population analyses demonstrated unique encoding of stimulus identity and behavioral choice information across regions, with V1 encoding stimulus, fMC encoding choice even early in the trial, and PPC multiplexing the two variables. Optogenetic inhibition during behavior revealed that all regions were necessary during the stimulus epoch, but only fMC was required during the delay and response epochs. Stimulus identity can thus be rapidly transformed into behavioral choice, requiring V1, PPC, and fMC during the transformation period, but only fMC for maintaining the choice in memory prior to execution.
将特定的感觉特征映射到未来的运动动作是哺乳动物神经系统的一项关键能力。我们研究了视觉皮层(V1)、顶叶后皮质(PPC)和额叶运动皮质(fMC)在小鼠执行记忆引导的视觉辨别任务期间对感觉运动映射的作用。大规模钙成像显示,V1、PPC和fMC神经元在所有任务阶段(刺激、延迟、反应)均表现出异质性反应。群体分析表明,跨区域对刺激身份和行为选择信息进行了独特编码,V1编码刺激,fMC甚至在试验早期就编码选择,而PPC则对这两个变量进行复用。行为期间的光遗传学抑制表明,在刺激阶段所有区域都是必需的,但在延迟和反应阶段仅需要fMC。因此,刺激身份可以迅速转化为行为选择,在转化期间需要V1、PPC和fMC,但在执行前仅需要fMC来维持记忆中的选择。