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The inferior temporal gyrus is placed below the middle temporal gyrus, and is connected behind with the inferior occipital gyrus; it also extends around the infero-lateral border on to the inferior surface of the temporal lobe, where it is limited by the inferior sulcus. This region is one of the higher levels of the ventral stream of visual processing, associated with the representation of complex object features, such as global shape. It may also be involved in face perception,〔Haxby indicates that a few studies have found face perception in the inferior temporal sulcus, with the majority of sites elsewhere in the brain: p.2, (Haxby, et.al. (2000) "The distributed human neural system for face perception" ''Trends in Cognitive Sciences'' 4 (6) June 2000, 11pp. )〕 and in the recognition of numbers. The inferior temporal gyrus is the anterior region of the temporal lobe located underneath the central temporal sulcus. The primary function of the inferior temporal gyrus - otherwise referenced as IT cortex - is associated with visual stimuli processing, namely visual object recognition, and has been suggested by recent experimental results as the final location of the ventral cortical visual system. The IT cortex in humans is also known as the Inferior Temporal Gyrus since it has been located to a specific region of the human temporal lobe. The IT processes visual stimuli of objects in our field of vision, and is involved with memory and memory recall to identify that object; it is involved with the processing and perception created by visual stimuli amplified in the V1, V2, V3, and V4 regions of the occipital lobe. This region processes the color and form of the object in the visual field and is responsible for producing the “what” from this visual stimuli, or in other words identifying the object based on the color and form of the object and comparing that processed information to stored memories of objects to identify that object.〔 The IT cortex’s neurological significance is not just its contribution to the processing of visual stimuli in object recognition but also has been found to be a vital area with regards to simple processing of the visual field, difficulties with perceptual tasks and spatial awareness, and the location of unique single cells that possibly explain the IT cortex’s relation to memory. ==Structure== The temporal lobe is unique to primates. In humans, the IT cortex is more complex than their relative primate counterparts. The human inferior temporal cortex consists of the inferior temporal gyrus, the middle temporal gyrus, and the fusiform gyrus. When looking at the brain laterally - that is from the side and looking at the surface of the temporal lobe - the inferior temporal gyrus is along the bottom portion of the temporal lobe, and is separated from the middle temporal gyrus located directly above by the inferior temporal sulcus. Additionally, some processing of the visual field that corresponds to the ventral stream of visual processing occurs in the lower portion of the superior temporal gyrus closest to the superior temporal sulcus. The medial and ventral view of the brain - meaning looking at the medial surface from below the brain, facing upwards - reveals that the inferior temporal gyrus is separated from the fusiform gyrus by the occipital-temporal sulcus. This human inferior temporal cortex is much more complex than that of other primates: non-human primates have an inferior temporal cortex that is not divided into unique regions such as humans' inferior temporal gyrus, fusiform gyrus, or middle temporal gyrus. This region of the brain corresponds to the inferior temporal cortex and is responsible for visual object recognition and receives processed visual information. The inferior temporal cortex in primates has specific regions dedicated to processing different visual stimuli processed and organized by the different layers of the striate cortex and extra-striate cortex. The information from the V1 –V5 regions of the geniculate and tectopulvinar pathways are radiated to the IT cortex via the ventral stream: visual information specifically related to the color and form of the visual stimuli. Through comparative research between primates - humans and non-human primates - results indicate that the IT cortex plays a significant role in visual shape processing. This is supported by functional magnetic resonance imaging (fMRI) data collected by researchers comparing this neurological process between humans and macaques. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Inferior temporal gyrus」の詳細全文を読む スポンサード リンク
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