A lesion affecting the superior temporal gyrus will result in receptive aphasia the person will have fluent speech that makes no sense. Wernicke's area is located in the superior temporal gyrus of the dominant hemisphere and manages the comprehension of language. It contains the primary auditory cortex which is involved in processing sound. The temporal lobe processes sensory input into derived meanings for the appropriate retention of emotions, visual memory, and language comprehension. However, in patients experiencing a seizure arising from the frontal eye fields will result in the eyes to look away from the lesion. The frontal eye fields are the central saccadic eye movement control area, damage to this area may cause eye deviation towards the side of the lesion. A frontal lobe lesion may also result in regression or a re-emergence of primitive reflexes. Thus, damage to this area may result in disinhibition and deficits in concentration, orientation, and judgment. The frontal lobes are critical for more difficult decisions and interactions that are essential for human behavior. The medial frontal cortex is also the central brain micturition center. Other frontal lobe areas including the orbitofrontal area and the medial frontal area are involved in a variety of higher functioning processing, such as regulating emotions, social interactions, and personality. The inferolateral areas of the dominant hemisphere (usually left side) of the frontal lobe are the expressive language area (Broca area, Brodmann areas 44 and 45), to which damage will result in a non-fluent expressive type of aphasia. Damage to any of these areas may lead to weakness and impaired execution of motor tasks of the contralateral side. The dorsolateral frontal lobe is divided into three major areas which include the prefrontal cortex, the premotor cortex, and the primary motor cortex. Both anatomically and functionally, it divides into different significant areas. The frontal lobe is the largest lobe of the brain, lying in front of the central sulcus. Each sensory area has associated sensations given specific stimuli, providing meaning to sensations. The motor regions of the cerebral cortex are located predominantly in the frontal lobe, anterior to the central sulcus, and include the primary motor cortex (found in the precentral gyrus) and the premotor cortex, which initiates and regulates voluntary movement. Other important primary cortical sensory areas include the temporal lobe auditory cortex and the occipital lobe visual cortex. The thalamus receives somatosensory information and conveys it to the primary somatosensory cortex in the postcentral gyrus of the parietal lobe. The cerebral cortex contains sensory, motor and important association areas. Notable sulci include the Sylvian fissure which divides the temporal lobe from the frontal and parietal lobe, the central sulcus which separates the frontal and parietal lobes, the parieto-occipital sulcus which divides the parietal and occipital lobes, and the calcarine sulcus which divides the cuneus from the lingual gyrus. The various folding of brain tissue allowed large brains to fit in relatively small cranial vaults that had to remain small to accommodate the birth process. It is the gray matter of the brain. Lying right under the meninges, the cerebral cortex divides into four lobes: frontal, temporal, parietal and occipital lobes, each with a multitude of functions. It is characteristically known for its bulges of brain tissue known as gyri, alternating with deep fissures known as sulci. The enfolding of the brain is an adaptation to the dramatic growth in brain size during evolution. The cerebral cortex is composed of a complex association of tightly packed neurons covering the outermost portion of the brain.
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