0


前额叶皮层与决策

Prefrontal cortex and decision-making
课程网址: http://videolectures.net/eccs08_funahashi_pcadm/  
主讲教师: Shintaro Funahashi
开课单位: 京都大学
开课时间: 2008-10-17
课程语种: 英语
中文简介:
众所周知,前额叶皮层参与了工作记忆过程。在延迟期(延迟期活动)中观察到的强直持续激活被认为是信息主动维护机制的神经关联。神经生理学研究表明,延迟期活动代表回顾性信息(如感觉事件)和前瞻性信息(如即将到来的运动信息)。这表明延迟期活动参与了基于感觉信息的运动性能决策过程。为了研究延迟期活动如何参与运动行为的决定,我们分析了当猴子执行两个任务时的前额活动:ODR和S-ODR任务。在ODR任务中,猴子被要求在3秒延迟后进行记忆引导的球拍到提示位置。在S-ODR任务中,四个相同的视觉提示在提示期间同时出现,猴子被要求在延迟后在任何一个方向上进行一次扫视。在相同的神经元中,两个任务的延迟期活动具有相似的方向性偏好。根据延迟期活动的时间模式和方向选择性的强度,将延迟期活动的神经元分为若干组。其中,在ODR任务的整个延迟期内具有持续定向选择性的延迟期活动类型增加的神经元在S-ODR任务中也表现出定向延迟期活动。这些结果表明,一种被认为代表运动信息的延迟周期活动的增加类型,在S-ODR任务中对产生和增强方向偏差起着重要作用,因此对S-ODR任务中的跳步方向的决策过程有着重要的贡献。
课程简介: The prefrontal cortex has been known to participate in working memory processes. Tonic sustained activation observed during the delay period (delay-period activity) has been considered as a neural correlate of the mechanism for active maintenance of information. Neurophysiological studies revealed that delay-period activity represents retrospective information (e.g., sensory events) as well as prospective information (e.g., forthcoming motor information). This suggests that delay-period activity participates in decision processes regarding motor performances based on the sensory information. To examine how delay-period activity participates in the decision of a motor behavior, we analyzed prefrontal activity while monkeys performed two tasks: ODR and S-ODR tasks. In the ODR task, monkeys were required to make a memory-guided saccade to the cue location after a 3-s delay. In the S-ODR task, four identical visual cues were presented simultaneously during the cue period and monkeys were required to make a saccade in any one direction after the delay. Delay-period activity was observed in both tasks in the same neuron with similar directional preferences. Neurons with delay-period activity were classified into several groups based on the temporal pattern of the activity itself and of the strength of the directional selectivity. Among these, neurons with an increasing type of delay-period activity with persistent directional selectivity throughout the delay period in the ODR task also showed directional delay-period activity in the S-ODR task. These results indicate that an increasing type of delay-period activity, which is thought to represent motor information, plays an important role in generating and enhancing directional bias in the S-ODR task and therefore contributes significantly to the decision process of the saccade direction in the S-ODR task.
关 键 词: 科学; 复杂性科学; 神经相关
课程来源: 视频讲座网
最后编审: 2019-12-07:lxf
阅读次数: 58