Brain and cranial nerves

Cell Body

Largest part of a typical neuron; contains the nucleus and much of the cytoplasm

Nucleus

Contains the neuron's DNA; controls cell activities.

Dendrites

Branch-like extensions that receive signals from other neurons.

Axon

Long fiber that transmits signals away from the cell body.

Axon Terminal

Ends of the axon where neurotransmitters are released.

Schwann Cell

Produces myelin in the peripheral nervous system.

Neuroglia

Supporting cells that protect and nourish neurons.

node of ranvier

a gap in the myelin sheath of a nerve, between adjacent Schwann cells.

Axon hillock

Cone shaped region of an axon where it joins the cell body.

Cerebrum

Largest brain region, responsible for conscious thought, learning, memory, and voluntary movement.

Cerebral Hemispheres

Left and right halves of the cerebrum, separated by the longitudinal fissure.

Longitudinal Fissure

Deep groove dividing the two cerebral hemispheres.

Transverse Fissure

Separates the cerebrum from the cerebellum.

Central Sulcus

Separates frontal and parietal lobes.

Lateral Sulcus

Separates temporal lobe from frontal and parietal lobes.

Precentral Gyrus

Primary motor cortex; controls voluntary muscle movement.

Postcentral Gyrus

Primary somatosensory cortex; processes body sensations.

Frontal Lobe

Responsible for planning, decision-making, voluntary movement, and speech (Broca's area).

Parietal Lobe

Processes touch, pressure, temperature, and pain.

Temporal Lobe

Involved in hearing, memory, and Wernicke's area (language comprehension).

Occipital Lobe

Processes visual information.

Prefrontal Cortex

Involved in complex thinking, planning, and personality.

Primary Motor Area

Located in the precentral gyrus; initiates movement.

Broca's Area

Controls speech production (usually in the left frontal lobe).💡 Mnemonic Tip: "Broca = Broken Speech"

Wernicke's Area

Controls speech comprehension (temporal lobe).💡 Mnemonic Tip: "Wernicke = Word Salad when damaged"

Primary Somatosensory Area

Receives and interprets sensory input.

Primary Visual Cortex

Interprets visual stimuli (occipital lobe).

Gray Matter

Contains neuron cell bodies; found on brain surface and inside spinal cord.(opposite of spinal cord)

White Matter

Myelinated axons; transmits signals between brain regions.

Corpus Callosum

Thick band of white matter connecting the two cerebral hemispheres.

Thalamus

Relay station for sensory information.( Diencephalon)

Hypothalamus

Regulates temperature, hunger, thirst, hormones.( Diencephalon)

Pituitary Gland

Master gland; releases hormones under hypothalamus control. ( Diencephalon)

Pineal Gland

Secretes melatonin; controls sleep-wake cycle. .*part of the epithalamus ( Diencephalon)

Mammillary Bodies

Involved in memory processing.( Diencephalon)

Midbrain

Coordinates visual and auditory reflexes.( Brain Stem)

Corpora Quadrigemina

Four bumps on the midbrain:( Brain Stem) Superior Colliculi = visual reflexes Inferior Colliculi = auditory reflexes

Pons

Relays information between the cerebrum and the cerebellum; assists in breathing. ( Brain Stem)

Medulla Oblongata

Controls vital functions—heart rate, breathing, blood pressure.( Brain Stem)

Cerebellum

Coordinates balance, posture, and fine motor movements.

Arbor Vitae

Tree-like white matter inside cerebellum/( Cerebellum)

“Some Say Marry Money But My Brother Says Big Brains Matter More”

Mnemonic for Function (S = Sensory, M = Motor, B = Both)

“Oh, once one takes the anatomy final, very good vacations are heavenly.”

Mnemonic for Cranial Nerves I-X

Olfactory Nerve (Sensory)

Cranial Nerve I - Responsible for sense of smell.

Optic Nerve (Sensory)

Cranial Nerve II - Responsible for vision.

Oculomotor Nerve (Motor)

Cranial Nerve III - Controls most eye movements, pupil constriction, and eyelid movement.

Trochlear Nerve (Motor)

Cranial Nerve IV - Moves the eye downward and laterally via the superior oblique muscle.

Trigeminal Nerve (Both)

Cranial Nerve V - Controls facial sensation, chewing muscles (mastication).

Abducens Nerve (Motor)

Cranial Nerve VI - Moves the eye laterally via the lateral rectus muscle.

Facial Nerve (Both)

Cranial Nerve VII - Controls facial expressions, taste on front 2/3 of tongue, and tears/saliva.

Vestibulocochlear Nerve (Sensory)

Cranial Nerve VIII - Responsible for hearing and balance.

Glossopharyngeal Nerve (Both)

Cranial Nerve IX - Controls taste on back 1/3 of tongue, swallowing, salivation.

Vagus Nerve (Both)

Cranial Nerve X - Regulates heart rate, digestion, and parasympathetic control of organs.

Accessory Nerve (Motor)

Cranial Nerve XI - Controls head, neck, and shoulder movement.

Hypoglossal Nerve (Motor)

Cranial Nerve XII - Controls tongue movements for speech and swallowing.