Exam 3 Key Points

Flashcards for exam review.

Absolute Refractory Period

Period during which another action potential cannot be generated.

Arbor Vitae

Cerebellar white matter that resembles a tree.

Bell’s Palsy

Paralysis of the facial nerve (CN VII).

Blood-Brain Barrier

A protective barrier that prevents certain substances from entering the brain.

Brachial Plexus

Network of nerves formed by spinal nerve ventral rami C5-T1; innervates the upper limb.

Brainstem

Midbrain, pons, and medulla oblongata.

Broca’s Area

Region in the frontal lobe of the dominant hemisphere, usually the left, with functions linked to speech production.

Cell bodies of preganglionic neurons of the CNS

Located in the brainstem and spinal cord.

CN I

Olfactory Nerve.

CN IX

Glossopharyngeal Nerve.

CN VI

Abducens Nerve.

CN VII

Facial Nerve.

CN VIII

Vestibulocochlear Nerve.

CN X

Vagus Nerve.

CN XI

Accessory Nerve.

Columns

Bundles of myelinated nerve fibers in the spinal cord.

Commissures

Connections between the two hemispheres of the brain.

Continuous Propagation

Action potential propagation involving nonmyelinated axons.

Depolarization

The process of making the membrane potential less negative.

Dorsal Ramus

Innervates the back.

Ependymal Cells

Neuroglial cells that line the ventricles of the brain and the central canal of the spinal cord.

Falx Cerebri

A fold of dura mater that separates the two cerebral hemispheres.

Filum Terminale

A fibrous extension of the pia mater that anchors the spinal cord to the coccyx.

Flow of CSF

Formed in the choroid plexus, circulates through ventricles and subarachnoid space, and is reabsorbed into the blood.

Function of the Thalamus

Relay station for sensory information, motor control, consciousness, sleep/wake cycles.

Golgi Tendon Organs

Sensory receptors within tendons that sense changes in muscle tension.

Hypoglossal Nerve

Cranial nerve XII; controls tongue movement.

Hypothalamus Functions

Regulates body temperature, hunger, thirst, sleep-wake cycles, and hormone release.

Medulla Oblongata Functions

Controls heart rate, breathing, and blood pressure.

Microglia

Phagocytic glial cells that remove waste products and pathogens in the brain.

Oligodendrocytes

Produce myelin in the CNS.

Parkinson's Disease

Neurodegenerative disorder affecting motor control due to loss of dopamine-producing neurons in the substantia nigra.

Phrenic Nerve

Nerve that innervates the diaphragm.

Primary Motor Cortex

Controls voluntary movements.

Proprioceptors

Sensory receptors that provide information about body position and movement.

Reflexes

Rapid, automatic responses to stimuli.

Schwann Cells

Produce myelin in the PNS.

Spatial Summation

The summation of potentials from different locations.

Special Senses

Olfaction, vision, gustation, equilibrium, and audition.

Spinal levels with no plexus formation

Thoracic.

Spinal Reflex Arc

Sensory receptor, afferent neuron, integration center, efferent neuron, effector.

Subarachnoid Space

Area between the arachnoid mater and pia mater, containing CSF.

Substantia Nigra

Midbrain structure that produces dopamine.

Sympathetic Functions

Fight or flight, increased heart rate, dilates pupils.

Threshold Voltage

Membrane potential at which an action potential is triggered; -55mV.

Voltage-Gated Channel

A channel that opens or closes in response to changes in the membrane potential.

Olfactory Cortex

Area in the temporal lobe responsible for the sense of smell.