Chapter 11: Central Nervous System - Vocabulary Flashcards

A set of vocabulary flashcards covering major CNS topics from the lecture notes, including structure, organization, regions, functions, protective mechanisms, and common clinical concepts.

Central Nervous System (CNS)

The brain and spinal cord; the master control and communication system producing fast electrical and chemical responses.

Peripheral Nervous System (PNS)

Cranial and spinal nerves that sense inputs from the body and transmit information to tissues.

Neuron

Excitable cell and basic functional unit of the nervous system; largely multipolar or pyramidal in the CNS.

Neuroglia

Supportive glial cells in the CNS, including oligodendrocytes, astrocytes, ependymal cells, and microglia.

Oligodendrocytes

Glial cells that form the myelin sheath around CNS axons.

Astrocytes

Glial cells involved in neurotransmitter regulation, brain structure, glycogenesis, fluid regulation, ATP release, and repair.

Ependymal cells

Ciliated cells that line brain ventricles and secrete cerebrospinal fluid (CSF).

Microglia

Resident macrophages of the CNS; remove damaged neurons and pathogens and participate in inflammation regulation.

Nuclei (in the CNS)

Specific clusters of neuronal cell bodies within the CNS.

White matter

CNS tracts consisting mainly of myelinated axons; enables rapid signal transmission.

Gray matter

Regions of the CNS containing neuronal cell bodies; includes cortex and nuclei.

Cerebrospinal Fluid (CSF)

Clear fluid that cushions, nourishes, and maintains homeostasis in the CNS; produced by the choroid plexus and circulates in ventricles and subarachnoid spaces.

Choroid plexus

Tissue in the ventricles that produces CSF. (

Ventricles (CNS)

Cavities in the brain: two lateral ventricles, third ventricle, and fourth ventricle.

Blood–Brain Barrier (BBB)

Selective barrier formed by tight junctions protecting the brain; regulates passage of substances.

Circle of Willis

Arterial ring that provides redundant blood supply to the brain by connecting anterior and posterior circulation.

Ischemic stroke

Stroke caused by reduced blood flow leading to neuronal death.

Hemorrhagic stroke

Stroke caused by bleeding within brain tissue.

Hydrocephalus

Condition of enlarged ventricles due to CSF accumulation.

Cerebrum

Largest brain region containing the cerebral hemispheres; includes cortex, white matter, basal nuclei, and limbic system.

Cerebral cortex

Outer gray matter (2–4 mm thick) of the cerebrum; site of conscious mind and higher processing; contains 5 lobes.

Cerebral white matter

Myelinated axon tracts (e.g., corpus callosum, fornix) connecting different brain regions.

Basal nuclei (basal ganglia)

Deep gray matter within the white matter that regulates movement and cognitive aspects of action.

Limbic system

Emotional and memory-related brain circuits; includes hippocampus and amygdala.

Hippocampus

Part of the limbic system; crucial for memory formation and spatial navigation.

Amygdala

Emotion processing and memory modulation within the limbic system.

Thalamus

Gateway to the cerebral cortex; relay station for sensory and motor signals; involved in arousal, learning, and memory.

Subthalamus

Diencephalic region involved in motor function.

Epithalamus

Diencephalic region containing the pineal gland; influences emotions and biological clock.

Hypothalamus

Key autonomic and endocrine control center; regulates homeostasis, temperature, hunger, thirst, sleep, and pituitary function.

Diencephalon

Central core of the forebrain composed of thalamus, subthalamus, epithalamus, and hypothalamus.

Brainstem

Stalk-like structure connecting brain to spinal cord (midbrain, pons, medulla); governs automatic functions and houses many cranial nerve nuclei.

Midbrain

Part of the brainstem involved in motor and sensory pathways and cranial nerve nuclei; includes cerebral peduncles and reflex centers.

Pons

Brainstem region that relays signals between medulla and higher brain centers; important for respiration.

Medulla oblongata

Brainstem region regulating autonomic functions (heart rate, blood pressure, respiration) and housing vital reflex centers.

Cerebellum

Posterior brain region that coordinates movement, posture, and motor learning; contains arbor vitae, vermis, and flocculonodular lobe.

Arbor vitae

White matter internal to the cerebellum forming its distinctive branching pattern.

Vermis

Median portion of the cerebellum essential for posture and locomotion.

Flocculonodular lobe

Cerebellar region involved in balance and eye movements.

Cerebral hemispheres

Left and right halves of the cerebrum; connected by commissures and exhibiting lateralization of function.

Gyrus

Ridge on the cerebral cortex surface.

Sulcus

Groove on the cerebral cortex surface.

Fissure

Deep groove separating brain regions (e.g., longitudinal and transverse fissures).

Longitudinal fissure

Deep groove that separates the left and right cerebral hemispheres.

Transverse fissure

Deep groove separating the cerebrum from the cerebellum.

Cerebral lobes

Five lobes of the cerebrum: frontal, parietal, occipital, temporal, and insula.

Frontal lobe

Lobe associated with personality, voluntary movement, higher intellect, social behavior, mood, and language; houses Broca’s area.

Parietal lobe

Lobe involved in sensory integration, language control, and visuospatial processing.

Occipital lobe

Lobe responsible for primary visual processing and visual association.

Temporal lobe

Lobe involved in memory, language comprehension, and auditory processing.

Insula

Lobe located within the lateral sulcus; involved in diverse functions including taste and vestibular processing.

Broca’s area

Region in the frontal lobe involved in speech production and planning.

Primary motor cortex

Motor area in the precentral gyrus; controls voluntary movements via corticospinal tracts.

Premotor cortex

Region anterior to the primary motor cortex; plans and coordinates learned movements.

Primary somatosensory cortex

Region in the postcentral gyrus; processes general somatic sensation and proprioception.

Somatosensory association cortex

Area that integrates sensory input to recognize objects felt (stereognosis).

Visual cortex

Primary visual processing area in the occipital lobe; includes primary and visual association areas.

Auditory areas

Primary auditory cortex and auditory association area in the temporal lobe.

Olfactory cortex

Smell-processing region located in the temporal lobe.

Gustatory cortex

Taste-processing area located in the insula.

Vestibular cortex

Region involved in balance processing (located in the insula and adjacent cortex).

Multimodal association areas

Regions that integrate information from multiple senses to guide decisions and actions.

Anterior association area

Region involved in intellect, cognition, memory, planning, judgment, and personality.

Posterior association area

Region involved in pattern recognition, spatial awareness, and language integration.

Limbic association area

Part of the limbic system involved in emotion and memory integration.

Corpus callosum

Large commissural tract linking the two cerebral hemispheres for interhemispheric communication.

Fornix

Major limbic system tract connecting hippocampus to other structures.

Contralateral control

Concept that each hemisphere predominantly controls opposite side of the body.

Contralateral hemispatial neglect

Condition from parietal lobe damage leading to neglect of the opposite side of space.

Contralateral homonymous hemianopia

Loss of vision in the opposite visual field due to damage in one hemisphere.

Spinal cord

Two-way conduction pathway between brain and body; major reflex center; extends from foramen magnum to L2.

Dorsal root ganglion

Cluster of sensory neuron cell bodies on dorsal root of a spinal nerve.

Dorsal root

Sensory afferent fibers entering the spinal cord.

Ventral root

Motor efferent fibers exiting the spinal cord.

Dorsal ramus

Spinal nerve branch that supplies the back and near-skin regions.

Ventral ramus

Spinal nerve branch that supplies the rest of the body.

Dermatome

Skin area innervated by a single spinal nerve.

Myotome

Group of muscles innervated by a single spinal nerve.

Cervical plexus

Network of ventral rami C1–C4; supplies neck muscles and skin; includes cutaneous and muscular branches.

Brachial plexus

Network of ventral rami C5–T1; innervates upper limb; major nerves include axillary, radial, ulnar, median, and musculocutaneous; phrenic nerve arises from C3–C5.

Lumbosacral plexus

Network of ventral rami L1–L4 and L4–S4; innervates lower limbs; major nerves include obturator, femoral, tibial, and common fibular; sciatic nerve formed by tibial and common fibular.

Cranial nerves

Twelve pairs of nerves arising from the brain; sensory, motor, or both; control many head and neck functions.

Meninges

Three protective membranes around the CNS: dura mater, arachnoid mater, and pia mater.

Dura mater

Outer, durable meningeal layer.

Arachnoid mater

Middle, delicate meningeal membrane with subarachnoid space beneath.

Pia mater

Inner meningeal layer that adheres to the brain’s surface.

Subdural space

Potential space between dura mater and arachnoid mater.

Subarachnoid space

Space between arachnoid and pia mater that contains CSF.

CSF production and flow

CSF produced by choroid plexus, circulates through ventricles and around the CNS, providing buoyancy and nourishment.

Neurogenesis

Generation of new neurons; occurs in fetal development and evidence suggests limited adult neurogenesis in certain regions.

Neuroplasticity

Brain’s ability to reorganize neural connections in response to learning or injury.

Reflex arc

Simple neural circuit consisting of a sensory neuron, motor neuron, and an effector; can be monosynaptic or polysynaptic.

Aging of the CNS

Age-related changes include neuron and glia loss, decreased conduction velocity, impaired waste clearance, and plaques/tangles leading to sensory, motor, and cognitive declines.