Neuromuscular Basics

Vocabulary flashcards covering the components of the CNS and PNS, reflex pathways, and the functions of the brainstem, cerebellum, and basal nuclei.

CNS components

The components of the Central Nervous System, which include the brain and spinal cord.

PNS components

Nerves outside the CNS, including cranial and peripheral nerves.

Afferent neurons

Sensory neurons that carry information to the CNS.

Efferent neurons

Motor neurons that carry signals away from the CNS to effectors like muscles.

Afferent (Direction)

The direction of signal travel for sensory neurons, which arrives to the CNS.

Efferent (Direction)

The direction of signal travel for motor neurons, which exits the CNS.

Nucleus

A cluster of neuron cell bodies within the CNS.

Ganglion

A cluster of neuron cell bodies within the PNS.

Muscle spindle function

A sensory organ that detects muscle length and stretch.

Muscle spindle afferent

The Type Ia afferent is used by this sensory organ.

GTO function

A sensory organ that detects tendon tension.

GTO afferent

The Type Ib afferent is used by this sensory organ.

Patellar reflex pathway

Tap tendon → quad stretches → muscle spindle fires Ia afferent → spinal cord → alpha motor neuron → quad contracts.

GTO/lengthening reflex pathway

High tendon tension → GTO fires Ib afferent → inhibitory interneuron → alpha motor neuron inhibited → muscle relaxes.

Withdrawal reflex

A reflex where a painful stimulus causes the same-side limb to flex away from the stimulus.

Crossed extensor reflex

A reflex where the opposite limb extends to support body weight while the injured limb withdraws.

Brainstem function (Motor)

Relays motor signals.

Brainstem function (Eyes)

Controls eye movements.

Brainstem function (Posture)

Regulates muscle tone and posture.

Cerebellum function (Coordination)

Coordinates movement.

Cerebellum function (Learning)

Supports motor learning.

Cerebellum function (Balance)

Maintains posture and balance.

Basal nuclei direct pathway

The pathway that initiates and facilitates voluntary movement.

Basal nuclei indirect pathway

The pathway that inhibits unwanted movement.

Parkinson's disease

A condition involving dopamine loss or understimulation in the basal nuclei, causing difficulty initiating movement and controlling unwanted movement.

Huntington's disease

A condition involving overstimulation in the basal nuclei that can cause uncontrolled jerking movements.