Modulation of Primate Somatosensory Cortical Responses

描述（由申请人提供）：我们的长期目标是了解在有目的的手部运动期间如何动态处理体感信息，以及与这些运动相关的运动活动如何随行为环境的变化而变化。作为以前工作的直接延伸，我们试图了解何时以及在什么情况下，行为的感觉反应和运动相关的感觉运动皮层活动的改变，在涉及使用部分任务信息的行为和决策过程中。这些实验使用受控行为，并系统地改变成功结果所需的线索。具体目标#1是确定当存在有关目标位置和/或运动开始时间的明确信息时，感觉运动皮质神经元的感觉反应和运动相关活动是否发生显着变化，如果是这样，则确定反应性变化是否与预测一致运动计划和执行期间的感觉反应性。使用单单位记录技术和行为动物，我们将确定是否调制的感觉运动皮层神经元的反应性和运动/活动的相关性不同时，运动可以计划使用信息的运动开始或目标位置，但不是在同一个行为试验。具体目标#2是确定在决策过程中，先前的成功是否会影响感觉运动皮层神经元的感觉反应和运动相关活动，如果是这样，确定当决策被强化或被取消时，反应性变化是否最大。我们还将确定感觉反应性和运动/活动相关性的变化如何与自由选择或指导范式中动物的有据可查的“赢-留-输-转换”决策行为相关。所有的发现都将与奖励历史相关，以了解它如何影响行为。在这两组实验中，将分析数据以量化皮层神经元表示相同但根据行为背景具有不同含义的外周感觉刺激的放电率和保真度。运动相关活动将被拟合到运动运动学，以确定作为行为函数的差异。涉及感觉运动皮质的中风是常见的，但通常随后会有良好的功能恢复。恢复可能是由于中枢神经系统重组。重组是由运动疗法，模仿正常的行为剧目促进。然而，是什么控制了正常基因组的表达，仍然知之甚少。通过了解在计划和决策行为过程中，体感反应和运动相关皮层活动是如何、在何处以及何时被修改的，可以更容易地评估和定位缺陷，并更适当地应用再训练策略。

DESCRIPTION (provided by applicant): Our long-term goals are to understand how somatosensory information is processed dynamically during purposeful hand movements and how motor activity associated with those movements differs with changes in behavioral context. As direct extensions of previous work, we seek to understand when and under what behavioral circumstances sensory responsiveness and movement-related sensorimotor cortical activity are altered during behaviors involving use of partial task information and during decision-making. These experiments use controlled behaviors and systematically vary cues needed for successful outcomes. Specific Aim #1 is to determine if, when explicit information about target location and/or timing of movement onset is present, sensory responses and movement-related activity of sensorimotor cortical neurons change significantly, and if so, to determine if responsiveness changes are consistent with predictions about sensory responsiveness during movement planning and execution. Using single-unit recording techniques and behaving animals, we will determine if modulation of sensorimotor cortical neuronal responsiveness and movement/activity correlations differ when movements can be planned using information about movement onset or target location, but not both in the same behavioral trial. Specific Aim #2 is to determine if, during decision-making, prior success influences sensory responses and movement-related activity of sensorimotor cortical neurons and if so, to determine if responsiveness changes are altered most when decisions are reinforced or when they are countermanded. We will also determine how changes in sensory responsiveness and movement/activity correlations relate to the well- documented "win-stay-loss-switch" decision-making behavior of animals in free-choice or instructed paradigms. All findings will be related to reward history to see how it influences behavior. In both sets of experiments, data will be analyzed to quantify firing rates and the fidelity with which cortical neurons represent peripheral sensory stimuli that are the same but have different meanings depending on behavioral context. Motor-related activity will be fitted to movement kinematics to determine differences as a function of behavior. Stroke involving sensorimotor cortices is common but often followed by good functional recovery. Recovery may be due to central nervous system reorganization. Reorganization is facilitated by movement therapy that mimics normal behavioral repertoires. What controls the expression of normal repertoire, however, is still poorly understood. By understanding how, where, and when somatosensory responsiveness and movement-related cortical activity are modified during planning and decision-making behaviors, deficits can be more readily assessed and localized, and retraining strategies more appropriately applied.