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Motor neuron
A motor neuron is a specialized type of nerve cell responsible for transmitting signals from the central nervous system to muscles, enabling movement. These neurons carry electrical impulses that trigger muscle contraction, making them essential for voluntary actions like walking or speaking, as well as involuntary responses such as reflexes. Motor neurons are located in the brain and spinal cord, with long axons that extend out to connect with muscle fibers across the body.
There are two main types of motor neurons: upper motor neurons, which originate in the brain and transmit signals to the spinal cord, and lower motor neurons, which extend from the spinal cord to directly innervate muscles. Damage to either type can lead to motor deficits, weakness, or paralysis. Diseases such as amyotrophic lateral sclerosis (ALS), spinal muscular atrophy, and certain types of neuropathy specifically target motor neurons, often leading to progressive loss of movement and muscle control.
Motor neurons are critical to the body’s ability to interact with and respond to the environment. Their precise signaling allows for coordinated movement and posture, and understanding how they function is central to both neuroscience research and the development of treatments for motor disorders.
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