NEURAL MECHANISMS CONTROLLING RECEPTIVE FIELD PARAMETERS

我这个项目的长期目标是确定相互联系在大脑皮层动力学和“感官知觉”中的作用。在这里，我将研究它们对初级视觉皮质的感受野参数和功能结构的影响。尽管大多数皮质区域的下行或水平连接与其相应的上升连接相当，或者在某些情况下比其更大，但这些相互连接对视觉信息处理的贡献几乎是完全未知的。在我作为NRSA博士前获得者期间，我证明了来自纹外区18区(V2)的可逆低温失活可以改变猫初级视觉皮质(17区(V1))的选择性和功能结构(Sailstad et。等人，1999年)。然而，由于冷却使几乎所有的皮质层失活，因此很难分离和识别18区通过其产生17区选择性和功能结构变化的神经元回路。因此，为了正确解释这些冷却数据，我打算使用GABA注射而不是冷却板来灭活猫18区特定层的一小部分区域。当18区被灭活时，我将通过同时记录17区的内在光信号和多单位细胞外信号来观察其对选择性和功能的影响。为了确定这些连接对动态感受野特性的贡献程度，为了有效地解释我关于倒易连接的作用的结果，我将停用区域18，并使用Ringach et使用的反向相关方法计算其对动态定向调整的影响。艾尔1997年。

The long-term goal of my project is to determine the role of reciprocal connections in cortical dynamics and "sensory perception". Here I shall investigate their effect on receptive field parameters and functional architecture of the primary visual cortex. Despite the fact that most cortical areas have descending or horizontal connections that are comparable to, or in some cases more massive than their corresponding ascending connections, the contribution of these reciprocal connections to the processing of visual information is almost completely unknown. During my time as a NRSA predoctorate recipient, I showed that reversible cryogenic inactivation of connections from the extrastriate region, area 18 (V2), alters both selectivity and functional structure of cat primary visual cortex (area 17 (V1)) (Sailstad et. al., 1999). However because cooling inactivated almost all the cortical layers, it is difficult to isolate and identify the neuronal circuitry through which area 18 produces changes in selectivity and functional architecture of area 17. Therefore to properly interpret this cooling data, I intend to use GABA injections instead of a cooling plate to inactivate a small region of a particular layer in cat area 18. While area 18 is inactivated, I will observe its effect on selectivity and function by simultaneously recording both the intrinsic optical signal and multi-unit extracellular signal from area 17. To determine the extent to which these connections contribute to dynamic receptive field properties, and to allow a valid interpretation of my results with regard to the role of reciprocal connections, I will inactivate area 18 and calculate its effect on dynamic orientation tuning with the reverse correlation method used by Ringach et. al. 1997.