Neuroanatomy: Brain Structures, Meninges, and Cranial Nerves

Meninges

Protective membranes covering the brain and spinal cord.

Dura Mater

The tough outer layer that protects the brain.

Arachnoid Layer

The middle meningeal layer that cushions the brain with CSF.

Pia Mater

The delicate inner layer that adheres closely to the brain surface.

Cerebral Spinal Fluid (CSF)

Fluid that cushions, nourishes, and protects the brain and spinal cord.

Frontal Lobe

Controls reasoning, planning, movement, and personality.

Parietal Lobe

Processes sensory information like touch, pressure, and spatial awareness.

Temporal Lobe

Involved in hearing, memory, and language comprehension.

Occipital Lobe

Primary center for vision.

Gyrus/gyri

Raised folds of the cortex that increase surface area.

Sulcus/sulci

Grooves between gyri that increase brain surface complexity.

Myelencephalon

Embryonic structure that develops into the medulla oblongata.

Medulla Oblongata

Controls vital functions like breathing and heart rate.

Metencephalon

Embryonic region that forms the pons and cerebellum.

Pons

Relays signals between the cerebrum and cerebellum, helps regulate sleep and breathing.

Cerebellum

Coordinates movement, posture, and balance.

Arbor Vitae

White matter in the cerebellum that looks tree-like and transmits signals.

Tectum

Roof of the midbrain involved in sensory reflexes.

Inferior Colliculus

Processes auditory reflexes and sound localization.

Superior Colliculus

Controls visual reflexes and eye movements.

Diencephalon

Brain region that includes the thalamus, hypothalamus, and related structures.

Thalamus

Relay station for sensory and motor signals to the cortex.

Massa Intermedia

Bridge of gray matter connecting the two thalami.

Hypothalamus

Regulates homeostasis, hormones, and drives like hunger and thirst.

Mammillary Bodies

Involved in memory processing and part of the limbic system.

Telencephalon

Embryonic region that develops into the cerebral hemispheres.

Corpus Callosum

Large fiber tract connecting the two hemispheres.

Splenium

Posterior portion of the corpus callosum connecting occipital lobes.

Genu

Anterior bend of the corpus callosum connecting frontal lobes.

Fornix

White matter tract connecting hippocampus to hypothalamus.

Cingulate Gyrus

Involved in emotion, motivation, and cognitive control.

Amygdala

Processes fear, emotion, and memory.

Hippocampus

Critical for learning and forming new memories.

Olfactory Bulb

Processes smell information from the nose.

Olfactory Tract

Carries smell information from the bulb to the brain.

Pyriform/Olfactory Cortex

Primary cortical area for smell perception.

Pineal Gland

Regulates circadian rhythms by secreting melatonin.

Pituitary Gland

Master endocrine gland controlling hormones.

Infundibulum

Stalk connecting the hypothalamus to the pituitary gland.

Spinal Cord

Transmits signals between the brain and body, controls reflexes.

Optic Nerve (II)

Carries visual information from the eye to the brain.

Optic Chiasm

Point where optic nerves partially cross.

Optic Tract

Pathway carrying visual signals from the chiasm to the brain.

Oculomotor Nerve (III)

Controls most eye movements and pupil constriction.

Trigeminal Nerve (V)

Provides facial sensation and controls chewing muscles.

Abducens Nerve (VI)

Controls lateral eye movement.

Lateral Ventricle

Paired cavities producing and circulating CSF.

Choroid Plexus

Tissue inside ventricles that produces CSF.

Third Ventricle

Midline cavity in the diencephalon containing CSF.

Fourth Ventricle

Cavity between brainstem and cerebellum holding CSF.

Cerebral Aqueduct

Narrow channel connecting third and fourth ventricles.