motor neuron
Movement signal sender
A motor neuron is a nerve cell that transmits signals from the brain or spinal cord to muscles, triggering movement.
Motor neurons form the final link in the chain from intention to action—when they degenerate, as in ALS, voluntary movement fails.
The disease attacks motor neurons, gradually causing paralysis.
Neuron's signal-sending projection
- dendriteNeuron's input branch
- somaBodily cells, excluding gametes
- synapseNerve signal crossing point
- myelinNerve fiber insulation
cell body · terminal · spinal cord · brainstem · efferent · interneuron · nerve fiber · cranial nerve
Motor neuron disease
- polioParalytic viral infection
- Lou Gehrig's diseaseDegenerative motor neuron condition
- neurodegenerationProgressive loss of neurons
- weaknessDeficiency in force
paralysis · wasting · fasciculation · spasticity · bulbar · progressive · atrophy · Stephen Hawking
Neuron's rapid electrical discharge
- neurotransmitterSynaptic chemical messenger
- acetylcholineNeurotransmitter for muscles and memory
- depolarizationLoss of electrical gradient
- repolarizationMembrane voltage reset
firing · impulse · excitation · potassium channels · vesicle · receptor · refractory period · threshold
Reduction in size
- innervationNerve supply to tissue
- twitchInvoluntary muscular jerk
- fiberPlant-based digestive aid
- recruitmentSeeking new personnel
skeletal muscle · voluntary movement · strength · force · tension · fatigue · atrophy · denervation
Change in position
- locomotionAbility to travel independently
- coordinationOrganized cooperative movement
- gaitLocomotion pattern
- reflexInvoluntary stimulus response
voluntary · posture · balance · dexterity · proprioception · muscle tone · stretch reflex · activation
axon
Neuron's signal-sending projection
myelin · cell body · terminal · spinal cord · brainstem · efferent · interneuron · nerve fiber · cranial nerve · peripheral nerve
ALS
Motor neuron disease
- polioParalytic viral infection
- Lou Gehrig's diseaseDegenerative motor neuron condition
- neurodegenerationProgressive loss of neurons
weakness · paralysis · wasting · fasciculation · spasticity · bulbar · progressive · atrophy · Stephen Hawking · ventilator
action potential
Neuron's rapid electrical discharge
- neurotransmitterSynaptic chemical messenger
- acetylcholineNeurotransmitter for muscles and memory
- depolarizationLoss of electrical gradient
repolarization · firing · impulse · excitation · potassium channels · vesicle · receptor · refractory period · threshold · excitatory
contraction
Reduction in size
- innervationNerve supply to tissue
- twitchInvoluntary muscular jerk
- fiberPlant-based digestive aid
recruitment · skeletal muscle · voluntary movement · strength · force · tension · fatigue · atrophy · denervation · fasciculation
movement
Change in position
- locomotionAbility to travel independently
- coordinationOrganized cooperative movement
- gaitLocomotion pattern
reflex · voluntary · posture · balance · dexterity · proprioception · muscle tone · stretch reflex · activation · recruitment
- cellscells, blood cell, cell theory, nerve cell, red blood cell
- nervous systembrain, nerves, spinal cord, axon, dendrite
- neurologybrain, synapse, synapses, axon, CNS
- neuroscienceMRI, brain, synapses, dendrite, neurotransmitters
- nerve cellsnerve cell, brain cell, axon, dendrite, glia
- Neurophysiologyaction potential, neurotransmitter, nerve impulse, presynaptic, depolarization
motor, motors, motorist, motorized, neuron, motoring, neurology, neurological, motorize