Neuroanatomy, Visual Cortex

The visual cortex is the primary cortical region of the brain that receives, integrates, and processes visual information relayed from the retinas. It is in the occipital lobe of the primary cerebral cortex, which is in the most posterior region of the brain. The visual cortex divides into five different areas (V1 to V5) based on function and structure. Visual information from the retinas that are traveling to the visual cortex first passes through the thalamus, where it synapses in a nucleus called the lateral geniculate. This information then leaves the lateral geniculate and travels to V1, the first area of the visual cortex. V1 is also known as the primary visual cortex and centers around the calcarine sulcus. Each hemisphere has its own visual cortex, which receives information from the contralateral eye. In other words, the right cortical areas process information from the left eye, and the left processes information from the right eye. The primary purpose of the visual cortex is to receive, segment, and integrate visual information. The processed information from the visual cortex is subsequently sent to other regions of the brain to be analyzed and utilized. This process is highly specialized and allows the brain to recognize objects and patterns quickly without a significant conscious effort.One advantage of this specialization is that other cortical regions are free to perform other computations such as those responsible for executive functioning and decision making. However, since visual processing is mostly an unconscious process, it can lead to misinterpretations of visual data, which are demonstrated by the efficacy of visual illusions.