4. Descending tracts are pathways by which motor signals are sent from the brain to
lower motor neurons. The lower motor neurons then directly innervate muscles to
produce movement.
Descending motor system plays a crucial role in voluntary movement control,
posture, and balance regulation. It coordinates the execution of complex motor
behaviors by transmitting commands from the brain to the spinal cord and muscles.
Key functions include; initiating and modulating voluntary movements, stabilizing
the body during postural changes, and integrating sensory information to maintain
equilibrium and coordinate movements.
12. Extrapyramidal tract
The extrapyramidal tract is a collection of motor pathways that control
involuntary, subconscious movements and muscle tone, distinct from the
voluntary, conscious control of the pyramidal tract.
The extrapyramidal tract regulates postural reflexes, muscle coordination, and
the initiation and modulation of movement. It plays a key role in coordinating
complex, automatic movements
Major components include the basal ganglia, substantia nigra, red nucleus, and
reticular formation in the brainstem, which interconnect to control motor
function.
15. Differences between the pyramidal and
extrapyramidal tracts
The pyramidal tract originates in the motor cortex and directly controls
voluntary, skilled movements. It is responsible for fine motor control and
precise, coordinated actions.
The extrapyramidal tract has a more diffuse origin and indirectly
regulates muscle tone, posture, and automatic movements. It coordinates
complex, subconscious motor functions.
The pyramidal tract is dedicated to voluntary, skilled movement, while
the extrapyramidal tract manages automatic, subconscious motor control.
They work in tandem to enable precise, coordinated actions.
