Learning and Adaptation in Primary Visual Cortex

描述（由申请人提供）：本提案的目的是研究学习和适应改变初级视觉皮层神经元定向调节的机制。学习辨别棒材取向的微小变化可以使首选取向接近棒材取向的细胞的取向调谐曲线锐化，而适应取向光栅则可以使首选取向接近于自适应取向的细胞的调谐曲线变宽并使调谐曲线峰值移位。了解这些现象将有助于我们对神经元处理的理解，这将在21世纪的临床和基础神经科学中发挥关键作用。具体目标1的目标是确定修改皮质内连接对于模拟网络中的学习和适应是否必要和充分，其中来自外侧膝状核的前馈输入为方向进行了剧烈调整，并将通过建立过去的建模工作来完成。具体目标2的目标是通过实验验证这样一种预测，即在清醒、非麻醉的受试者中，适应会导致生理变化，这是学习中所见变化的短暂版本。

DESCRIPTION (provided by applicant): The goal of this proposal is to investigate the mechanism by which learning and adaptation can alter the orientation tuning of neurons in primary visual cortex. Learning to discriminate small changes in the orientation of a bar has been shown to sharpen the orientation tuning curves of cells whose preferred orientation is near the bar's orientation, while adapting to an oriented grating has been shown to broaden the tuning curves and shift the tuning curve peaks of cells whose preferred orientation is near the adapted orientation. Understanding these phenomena will contribute to our understanding of neuronal processing, which will play a critical role in both clinical and basic neuroscience in the twenty-first century. The goal of Specific Aim 1 is to determine whether modifying intracortical connections is necessary and sufficient for simulating learning and adaptation in a network where the feed-forward input from the lateral geniculate nucleus is sharply tuned for orientation, and will be accomplished by building on past modeling efforts. The goal of Specific Aim 2 is to experimentally test the prediction that adaptation in alert, non-anesthetized subjects causes physiological changes that are a transient version of the changes seen in learning.