The motor cortex is a region of the outer sheet of brain tissue called the cerebral cortex. The mov...
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The motor cortex is a region of the outer sheet of brain tissue called the cerebral cortex. The movement of every part of the body is controlled by a particular region of the motor cortex. The motor cortex is divided into two parallel bands. Based on information received from other parts of the brain, the band in front, called the pre-motor cortex, decides which muscles to contract to achieve a specific movement. The band behind, called the primary motor cortex, receives this information and activates specific muscles or groups of muscles through motor neurons in the spinal cord. A seizure is an uncoordinated shaking of the body that occurs when cells in the motor cortex fire out of sequence. When only a small portion of the motor cortex is involved, only a portion of the muscles of the body, like an arm or a leg, shakes uncontrollably. When more of the motor cortex is involved, almost all the muscles of the body convulse, causing the person to fall down, lose consciousness, and to shake all over.