5 Motor Systems Free Online FlashCards

What do association and premotor areas contribute to voluntary action?

Association and premotor areas help choose actions and prepare their sequences using sensory information and context.

What is a key role of primary motor cortex (M1)?

Primary motor cortex contributes to executing and finely controlling voluntary movements; its activity is distributed across neuron populations.

What do basal ganglia circuits contribute to movement?

They help select and initiate appropriate actions while reducing competing actions.

What do cerebellar circuits contribute to movement?

They compare intended with actual movement, help adjust timing and coordination, and support error-based motor learning.

Where do most corticospinal fibers cross?

Most corticospinal fibers cross at the lower medulla and descend as the lateral corticospinal tract.

What kind of movement does the lateral corticospinal tract especially support?

The lateral corticospinal tract is important for skilled movements, especially movements of distal limbs.

What does the corticobulbar pathway control?

It carries cortical motor signals to brainstem cranial-nerve motor nuclei, helping control muscles of the face, jaw, tongue, and neck.

How do vestibulospinal pathways support movement?

Vestibulospinal pathways use vestibular information to help stabilize posture.

What orienting movement do tectospinal pathways help produce?

Tectospinal pathways help orient the head and neck toward salient sights or sounds.

How do spinal interneurons help coordinate movement?

They link sensory input, motor-neuron activity, and muscle groups, helping coordinate actions such as limb withdrawal or alternating the legs during walking.

What is a motor unit?

A motor unit consists of one lower motor neuron and all the muscle fibers it activates.

Why are lower motor neurons called the final common pathway?

Lower motor neurons are the final common pathway because their activity directly drives skeletal-muscle contraction.