Chapter 14 – The Brain and Cranial Nerves (Vocabulary)

A comprehensive set of vocabulary flashcards covering key anatomical structures, physiological functions, and clinical concepts from Chapter 14: The Brain and Cranial Nerves.

Cranial Bones

The skull bones that form a rigid protective case around the brain.

Cranial Meninges

Three connective-tissue layers (dura, arachnoid, pia mater) that protect, nourish, and stabilize the brain.

Pia Mater

Delicate innermost meningeal layer that adheres tightly to the brain surface.

Arachnoid Mater

Middle, web-like meningeal layer that encloses the subarachnoid space holding CSF.

Dura Mater

Tough, outer fibrous meningeal layer that forms dural folds and venous sinuses.

Cerebrospinal Fluid (CSF)

Clear fluid that cushions the CNS, transports nutrients, and removes wastes.

Brainstem

Inferior brain region composed of medulla oblongata, pons, and midbrain.

Medulla Oblongata

Brainstem part that houses cardiovascular and respiratory centers and reflexes such as swallowing and vomiting.

Pons

Brainstem bridge that relays signals between cerebrum and cerebellum and helps regulate breathing.

Midbrain

Superior brainstem segment containing visual/auditory reflex centers and motor/sensory tracts.

Reticular Formation

Network of gray matter in brainstem that maintains consciousness and muscle tone.

Cerebellum

Posterior brain region that coordinates movement and maintains posture and balance.

Vermis

Central constricted area connecting the two cerebellar hemispheres.

Diencephalon

Central brain region containing thalamus, hypothalamus, and epithalamus.

Thalamus

Major relay station for all sensory input (except smell) to the cerebral cortex.

Hypothalamus

Homeostatic control center that regulates ANS, hormones, temperature, hunger, thirst, and circadian rhythms.

Epithalamus

Diencephalon segment housing the pineal gland and habenular nuclei.

Pineal Gland

Epithalamic endocrine organ that secretes melatonin to regulate sleep–wake cycles.

Cerebrum

Largest brain portion, responsible for higher functions; divided into lobes and two hemispheres.

Frontal Lobe

Anterior cerebral lobe involved in voluntary movement, reasoning, and speech production.

Parietal Lobe

Cerebral lobe that processes somatic sensory information and spatial perception.

Temporal Lobe

Side cerebral lobe devoted to auditory perception, memory, and language comprehension.

Occipital Lobe

Posterior cerebral lobe dedicated to visual processing.

Insula

Deep cerebral lobe located within the lateral sulcus involved in taste and visceral sensation.

Cerebral Cortex

Outer gray-matter layer of the cerebrum containing billions of neuron cell bodies.

Gyri

Elevated folds of the cerebral cortex that increase surface area.

Sulci

Shallow grooves between gyri on the cerebral surface.

Fissures

Deep grooves separating large brain regions, e.g., longitudinal fissure.

White Matter

Deep cerebral tissue composed of myelinated axon tracts connecting brain regions.

Corpus Callosum

Large commissural white-matter tract linking the right and left cerebral hemispheres.

Limbic System

Interconnected structures that govern emotion, motivation, and memory.

Sensory Areas (Cortex)

Cortical regions that receive and perceive sensory information.

Motor Areas (Cortex)

Cortical regions that initiate voluntary skeletal-muscle movements.

Association Areas

Cortical regions responsible for integration, reasoning, memory, and personality.

Broca’s Area

Frontal lobe speech center that produces language (motor speech).

Wernicke’s Area

Temporal/parietal region that comprehends spoken and written language.

Blood–Brain Barrier (BBB)

Selective barrier formed by capillary endothelial tight junctions that restrict passage of substances from blood to brain.

Ventricles

Four CSF-filled cavities (lateral, third, fourth) within the brain.

Choroid Plexus

Capillary network in ventricles that produces cerebrospinal fluid.

Cerebrovascular Accident (Stroke)

Loss of brain function due to interrupted blood flow; can be ischemic or hemorrhagic.

Transient Ischemic Attack (TIA)

Short-term neurological deficit caused by brief cerebral blood-flow reduction.

Alzheimer’s Disease

Progressive neurodegenerative dementia marked by β-amyloid plaques and neurofibrillary tangles.

Brain Tumor

Abnormal intracranial tissue growth that may be benign or malignant.

Attention Deficit Hyperactivity Disorder (ADHD)

Neurobehavioral disorder characterized by inattention, hyperactivity, and impulsivity.

Aging Effects on Nervous System

Gradual neuron loss, slower conduction, slower reflexes, and sensory decline with age.

Cranial Nerves

Twelve pairs of nerves that emerge from the brain and supply head and neck structures.

Olfactory Nerve (I)

Sensory cranial nerve for smell; originates from cerebrum.

Optic Nerve (II)

Sensory cranial nerve for vision; originates from cerebrum.

Oculomotor Nerve (III)

Motor nerve controlling most eye movements, pupil constriction, and lens shape.

Trochlear Nerve (IV)

Motor nerve that moves the eyeball via the superior oblique muscle.

Trigeminal Nerve (V)

Mixed nerve providing facial sensation and mastication muscles.

Abducens Nerve (VI)

Motor nerve that abducts the eye via the lateral rectus muscle.

Facial Nerve (VII)

Mixed nerve for facial expression, taste (anterior 2⁄3 tongue), and salivation/tear secretion.

Vestibulocochlear Nerve (VIII)

Sensory nerve for hearing (cochlear) and equilibrium (vestibular).

Glossopharyngeal Nerve (IX)

Mixed nerve for taste (posterior 1⁄3 tongue), swallowing, and saliva secretion.

Vagus Nerve (X)

Mixed nerve supplying thoracic/abdominal organs; influences heart rate, digestion, and voice.

Accessory Nerve (XI)

Motor nerve controlling sternocleidomastoid and trapezius muscles.

Hypoglossal Nerve (XII)

Motor nerve that moves the tongue for speech and swallowing.

Brain Waves

Electrical rhythms of cortical activity measured by EEG.

Alpha Waves

8–13 Hz rhythms present when awake and relaxed with eyes closed.

Beta Waves

14–30 Hz rhythms seen during active thinking and sensory input.

Theta Waves

4–7 Hz waves prominent in children and in adults under emotional stress.

Delta Waves

0.5–4 Hz waves typical of deep sleep in adults; normal in awake infants.

Hemispheric Lateralization

Functional asymmetry between right and left cerebral hemispheres.

Right Hemisphere Functions

Controls left body; handles spatial, artistic, facial-emotion, and emotional speech aspects.

Left Hemisphere Functions

Controls right body; dominates language, reasoning, math, and scientific skills.

Corpus Striatum

Basal nuclei group that initiates/terminates movement and regulates muscle tone.

Superior Colliculi

Midbrain nuclei coordinating visual reflexes of head, eyes, and trunk.

Inferior Colliculi

Midbrain nuclei coordinating auditory reflexes of head, eyes, and trunk.

Substantia Nigra

Midbrain nucleus rich in dopamine neurons that modulate motor control; degeneration causes Parkinson’s.

Red Nucleus

Midbrain motor relay involved in subconscious limb flexion.

Pontine Respiratory Group

Pons center that, with medulla, fine-tunes breathing rhythm.

Cardiovascular Center

Medullary nucleus regulating heart rate and blood vessel diameter.

Inferior Olivary Nucleus

Medulla relay providing motor learning signals to the cerebellum.

Feeding Center

Hypothalamic area that stimulates hunger and food intake.

Satiety Center

Hypothalamic area that suppresses hunger when nutrients are sufficient.

Suprachiasmatic Nucleus

Hypothalamic clock that sets circadian rhythms based on light cues.

Neural Tube

Embryonic structure formed from the neural plate that develops into the CNS.

Prosencephalon

Forebrain primary vesicle that forms telencephalon and diencephalon.

Mesencephalon

Primary brain vesicle that remains the midbrain in the adult.

Rhombencephalon

Hindbrain primary vesicle that forms metencephalon and myelencephalon.