Nervous System and Speech Motor Control Vocabulary

Vocabulary flashcards covering key terms and concepts related to the nervous system and motor control for speech from the lecture notes.

Nervous System

The body's communication and control system, which includes both central and peripheral divisions.

Central Nervous System

The division of the nervous system made up of the brain and spinal cord.

Peripheral Nervous System

The division located outside the brain and spinal cord that includes cranial nerves, spinal nerves, and ganglia.

Somatic

A type of nervous system control that includes voluntary control of skeletal muscles, which speaking depends heavily on.

Visceral

A term describing sensory and motor information associated with internal organs.

Neurons

Specialized cells that receive, process, and transmit information, considered the basic functional cells of the nervous system.

Axon

A long extension that carries electrical impulses away from a neuron's cell body.

Nerves

Bundles of nerve fibers found in the PNS that carry information between the CNS and the rest of the body.

Synapse

The junction where one neuron communicates with another neuron or another target cell.

Neurotransmitter

A chemical messenger released by a neuron that crosses a synapse and can increase or decrease the activity of another cell.

Afferent System

System that carries sensory information toward the CNS ('arrives').

Efferent System

System that carries motor commands away from the CNS toward muscles and glands ('exits').

Excitatory Impulse

A type of neural activity that increases the likelihood that another neuron or target cell will become active.

Inhibitory Impulse

A type of neural activity that decreases the likelihood of another neuron becoming active, helping prevent excessive or unwanted activity.

Final Common Pathway

The lower motor neuron connection through which voluntary movement signals ultimately reach skeletal muscle regardless of where they were planned or modified.

Cerebral Cortex

The outer layer of the cerebrum involved in cognition, sensory processing, language, planning, and voluntary movement.

Motor Cortex

Area located in the frontal lobe, particularly the percental gyrus, that helps produce voluntary movements of structures such as the lips, jaw, and tongue.

Ganglia

Collections of neuron cell bodies located outside the CNS.

Nuclei

Groups of neuron cell bodies located inside the CNS.

Reticular Formation

A network extending through the brainstem that contributes to arousal, attention, posture, muscle tone, automatic function, and motor control.

Spinal Nerves

Nerves arising from the spinal cord that carry both sensory and motor information, some of which help control respiratory muscles important for speech.

Cranial Nerves

12 pairs of nerves where several (including V, VII, IX, X, XI, and XII) play an important role in speech, voice, and swallowing.

Pathways or tracts

Bundles or networks of axons within the CNS that carry information from one area to another.

Corticospinal and corticobulbar tracts

Descending pathways where one primarily influences muscles through spinal nerves, while the other carries motor signals to cranial nerve nuclei in the brainstem.

Direct Activation Pathway

A relatively direct route from the motor cortex toward lower motor neurons that fine, skilled voluntary movements used for speech depend heavily on.

Cerebellum

A structure located behind the brainstem that helps coordinate the timing, force, accuracy, and smoothness of movement.

Thalamus

A deep brain structure serving as an important relay and participating in motor circuits connecting the cerebellum and basal ganglia with the cerebral cortex.

Basal Ganglia

Interconnected structures deep within the brain that help initiate, regulate, and refine movement, including its speed and force.

Automatic Nervous System

System that regulates involuntary function such as heart rate, digestion, pupil size, and gland activity.

Indirect Activation Pathway

A motor system using more indirect connections to help regulate posture, muscle tone, automatic movement, and the background support needed for voluntary movement.