The inferior pulvinar and visual attention

描述（由申请人提供）：枕核与大部分视觉皮层密切相关，导致许多人提出大脑这个神秘部分的视觉作用。然而，很少有人知道它在视觉处理中的作用。在损伤、成像和记录研究的基础上，已经提出枕在将视觉注意力引导到空间的特定区域中起作用。在拟议的实验中，我们计划使用电微刺激和可逆失活直接检验这一假设。我们将测量视觉检测性能和神经元反应的纹外皮层，有和没有扰动。检测任务将是运动方向的变化，我们已经知道皮层区MT参与这种感知能力。该设计允许进行两种不同的比较，每种比较对该假设都至关重要。首先，我们知道，定向注意产生的行为效益和局部变化的增益反应的纹外神经元;枕的激活应模仿这种变化和可逆失活应消除它。此外，我们将能够得出结论，是否感知测量的影响可以通过已知的皮层回路支持视觉辨别介导。

DESCRIPTION (provided by applicant): The pulvinar nucleus is richly interconnected with most of visual cortex, leading many to propose a visual role for this enigmatic part of the brain. However, little is known about its role in visual processing. On the basis of lesion, imaging, and recording studies, it has been proposed that pulvinar plays a role in directing visual attention to particular regions of space. In the proposed experiments, we plan to directly examine this hypothesis using electrical microstimulation and reversible inactivation. We will measure both visual detection performance and neuronal responses in extrastriate cortex, with and without perturbation. The detection task will be of a change in motion direction, and we already know that cortical area MT is involved in this kind of perceptual capability. The design allows two distinct comparisons to be made, each critical to this hypothesis. First, we know that directed attention produces behavioral benefits and local changes in the gain of response of extrastriate neurons; activation of pulvinar should mimic this change and reversible inactivation should eliminate it. Also, we will be able to conclude whether the effects measured perceptually could be mediated through known cortical circuits supporting visual discrimination.