A motoneuron or a motor neuron is a nerve cell located in the brain and the spinal cord that is responsible for controlling muscles' activity. There are a few synonyms for the word motoneuron, which can be used interchangeably. They include motor nerve cell, efferent neuron, alpha motor neuron, and ventral horn cell. A motor neuron's role is vital as they maintain the connection between the brain and the muscles that enables us to perform daily physical tasks like moving, holding, and grasping objects. Damage to the motoneuron can cause disorders like ALS, or amyotrophic lateral sclerosis, which affects motor neuron function and eventually leads to paralysis of the muscles.