Motor Cortex

Primary Motor Cortex

The brain region responsible for controlling voluntary movements, particularly those related to the limbs and trunk.

Corticospinal Tract

The main voluntary movement pathway that runs from the motor cortex to the spinal cord, controlling muscles of the limbs and trunk.

Corticobulbar Tract

A neural pathway that originates in the cerebral cortex and innervates cranial motor neurons for voluntary control of face, head, and neck movements.

Motor Homunculus

A representation of the body in the motor cortex, illustrating the motor function associated with different body parts.

Corticomotoneurons

Pyramidal neurons in the lateral corticospinal tract that synapse directly onto lower motor neurons, crucial for fine motor control.

Upper Motor Neuron Damage

Injury to neurons that affects multiple muscle groups, causing weakness, spasticity, and hyperreflexia.

Lower Motor Neuron Damage

Injury to neurons that affects individual muscles or muscle groups, leading to weakness, hypotonia, and muscle wasting.

Decussation

The crossing of nerve fibers from one side of the CNS to the other, which occurs at the medulla-spinal cord junction in the corticospinal tract.

Extrapyramidal Tracts

Neural pathways originating in the brainstem that control involuntary muscle movements, balance, and posture.

Cerebral Stroke

A condition resulting from blocked blood flow to the brain, often leading to damage in areas like the primary motor cortex.