<P> Excluding reflexes , all skeletal muscles contractions occur as a result of conscious effort originating in the brain . The brain sends electrochemical signals through the nervous system to the motor neuron that innervates several muscle fibers . In the case of some reflexes , the signal to contract can originate in the spinal cord through a feedback loop with the grey matter . Other actions such as locomotion , breathing , and chewing have a reflex aspect to them : the contractions can be initiated both consciously or unconsciously . </P>
<P> Excluding reflexes , all skeletal muscles contractions occur as a result of conscious effort originating in the brain . The brain sends electrochemical signals through the nervous system to the motor neuron that innervates several muscle fibers . In the case of some reflexes , the signal to contract can originate in the spinal cord through a feedback loop with the grey matter . Other actions such as locomotion , breathing , and chewing have a reflex aspect to them : the contractions can be initiated both consciously or unconsciously . </P>
where does the stimulus for muscle contraction normally originate in the body
where does the stimulus for muscle contraction normally originate in the body
the brain
the brain