Other Definitions
visual cortex (dict)
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Visual CortexThe visual cortex is the part of the cerebral cortex that is responsible for processing visual stimuli. It is located at the back of the brain in the occipital lobe. It is highly specialized for processing information about static and moving objects and is excellent in pattern recognition. Anatomically, the visual cortex occupies the entire occipital lobe, the inferior temporal lobe (IT), posterior parts of the parietal lobe, and a few small regions in the frontal lobe. David H. Hubel and Torsten Wiesel received the Nobel Prize in Physiology or Medicine in 1981 for their work on the visual cortex. The visual cortex occupies about one third of the surface of the cerebral cortex in humans. It is divided into approximately thirty interconnected visual areas. The first cortical visual area, the one that receives information directly from the lateral geniculate nucleus, is the Primary Visual Cortex, or V1. V1 transmits information to two primary pathways, called the ventral stream and the dorsal stream: Neurons in the visual cortex fire action potentials when visual stimuli appear within their receptive field. A receptive field is a small region within the entire visual field. Any given neuron only responds to a subset of stimuli within its receptive field. This property is called tuning. In the earlier visual areas, neurons have simpler tuning. For example, a neuron in V1 may fire to any vertical stimulus in its receptive field. In the higher visual areas, neurons have complex tuning. For example, in the inferior temporal cortex (IT), a neuron may only fire when a certain face appears in its receptive field. External links
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