REPRESENTATION OF FAMILIAR IMAGES IN VENTRAL STREAM VISUAL CORTEX

腹侧流视觉皮层中熟悉图像的表征

• 批准号: 9886926
• 负责人: TAI-SING LEE
• 金额: $ 45.85万
• 依托单位: CARNEGIE-MELLON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9886926
• 关键词: Animals; Area; Back; Behavior; Chronic; Code; Development; Diagnosis; Discrimination; Exhibits; Eye; Face; Familiarity; Human; Image; Injury; Interneurons; Knowledge; Lateral; Lead; Learning; Measurement; Measures; Mediating; Microelectrodes; Modification; Monitor; Monkeys; Nature; Neurons; Noise; Occipital lobe; Population; Reporting; Resistance; Site; Stream; Structure; Synapses; Temporal Lobe; Testing; V2 neuron; Vision; Vision Disorders; Visual; Visual Cortex; Weight; area V2; base; design; excitatory neuron; experience; experimental study; extrastriate visual cortex; falls; improved; inferotemporal cortex; multi-electrode arrays; neuromechanism; novel; object recognition; postsynaptic; postsynaptic neurons; receptive field; response; spatial integration; statistical learning; trend; visual information; visual plasticity; visual processing

We rely for object recognition on hierarchical processing of visual input by the ventral stream of cortical visual areas. The chain begins in low-order cortex (including area V2) where neuronal activity represents local features and terminates in inferotemporal cortex (including area TE) where neuronal activity represents global images. Neuronal function in the ventral stream is subject to alteration by visual experience. One particularly robust form of visual plasticity is familiarity suppression. Familiarity suppression can be induced in TE by allowing subjects to view the same set of images repeatedly over the course of days and weeks. At the end of the familiarization period, the mean strength of neuronal responses in TE is less for the familiar images than for novel controls. On the assumption that familiarity suppression is specific to TE, it has been thought to serve some function related to late-stage processing of the global image. Recently, however, familiarity suppression has been shown to occur even in V2, where neurons represent local features and not entire objects. On the basis of this observation, we propose that familiarity suppression, far from being specific to late-stage processing of the global image, arises from principles of unsupervised statistical learning operative at each stage of the ventral stream and expressed at each stage relative to the nature and scale of represented visual information. We will test this general idea by using semi-chronic multielectrode arrays to monitor neuronal population activity simultaneously in V2 and TE during image familiarization. Experiments under Aim 1 will test the hypothesis that familiarity suppression develops independently in V2 and is not just fed back from TE. Experiments under Aim 2 will test the hypothesis that familiarization enhances the cooperative representation of an image by neuronal populations in V2 and TE. Experiments under Aim 3 will test the idea that the synaptic alterations underlying the impact of familiarization obey a Hebbian learning rule.

我们依赖于通过大脑皮层腹侧流对视觉输入进行分层处理的对象识别 视觉区域。该链起始于低阶皮质(包括V2区)，那里的神经元活动代表局部 神经元活动代表全局性的颞下皮质(包括TE区)的特征和终末 图像。腹侧流中的神经元功能会受到视觉经验的影响。其中一个特别的 视觉可塑性的强健形式是熟悉性抑制。TE中的熟悉感抑制可以通过以下方式被诱导 允许受试者在几天或几周的过程中重复观看同一组图像。在…的末尾 熟悉期，TE中神经元反应的平均强度在熟悉的图像中小于在 新奇的控制。假设熟悉感抑制是TE所特有的，它被认为是有用的 与全局图像的后期处理相关的一些功能。然而，最近，熟悉感抑制 已被证明即使在V2中也存在这种情况，在V2中，神经元代表局部特征，而不是整个物体。论 基于这一观察，我们提出熟悉性抑制，远不是针对晚期的 全局图像的处理产生于每个操作的无监督统计学习的原理 腹侧流的阶段，在每个阶段表达，与所代表的视觉的性质和规模相关 信息。我们将通过使用半慢性多电极阵列来监测神经元来检验这一普遍想法 在图像熟悉过程中，V2和TE中的群体活动同时进行。目标1下的实验将测试 该假说认为熟悉性抑制在V2中独立发展，而不是仅仅从TE反馈。 目标2下的实验将检验熟悉度提高合作表征的假设。 V2和TE中的神经元群对图像的影响。目标3下的实验将测试突触 熟悉的影响下的变化遵循希伯来的学习规则。