Pharyngeal Arches, Cranial Nerves, and Brain Functions

Arch 1 - Muscles & Nerve

Muscles of mastication (masseter, temporalis, medial/lateral pterygoid), anterior belly of digastric, mylohyoid. Nerve: CN V₃ (Mandibular).

Arch 2 - Muscles & Nerve

Muscles of facial expression, posterior belly of digastric, stylohyoid, platysma. Nerve: CN VII (Facial).

Arch 3 - Muscle & Nerve

Stylopharyngeus. Nerve: CN IX (Glossopharyngeal).

Arches 4-6 - Muscles & Nerve

Pharyngeal constrictors, cricothyroid, laryngeal muscles. Nerve: CN X (Vagus).

Olfactory (I)

Smell; Cribriform plate.

Optic (II)

Vision; Optic canal.

Oculomotor (III)

Eye muscles, pupil constriction; Superior orbital fissure.

Trochlear (IV)

Superior oblique muscle; Superior orbital fissure.

Trigeminal (V)

V₃ Mandibular - Sensory (lower face), motor (mastication); Foramen ovale.

V₁ Ophthalmic

Sensory (forehead); Superior orbital fissure.

V₂ Maxillary

Sensory (midface); Foramen rotundum.

V₃ Mandibular

Sensory (lower face and anterior 2/3 of tongue), motor (mastication); Foramen ovale.

Abducens (VI)

Lateral rectus; Superior orbital fissure.

Facial (VII)

Facial expression, taste (ant 2/3), salivation; Internal acoustic meatus.

Vestibulocochlear (VIII)

Hearing & balance; Internal acoustic meatus.

Glossopharyngeal (IX)

Tongue sensation (post 1/3) Taste (post 1/3), swallowing; Jugular foramen.

Vagus (X)

Autonomic to thorax/abdomen, pharynx/larynx motor; Jugular foramen.

Spinal Accessory (XI)

Trapezius, SCM; Jugular foramen & foramen magnum.

Hypoglossal (XII)

Tongue movement; Hypoglossal canal.

Frontal Lobe

Speech, planning, problem-solving.

Parietal Lobe

Language processing, touch perception.

Temporal Lobe

Sound recognition.

Occipital Lobe

Vision.

Thalamus

Sensory relay station.

Hypothalamus

Homeostasis, endocrine control.

Cerebellum

Coordination, balance.

Pons

Modifies medullary signals.

Medulla Oblongata

Autonomic control (heart, breath).

Corpus Callosum

Interhemispheric communication.

Pituitary Gland

Hormone release.

Sclera

Protection and shape.

Cornea

Light entry and coarse focus.

Choroid

Vascular supply.

Ciliary Body

Lens shape control.

Iris

Controls pupil size.

Lens

Fine focusing.

Retina

Houses photoreceptors.

Rods/Cones

Light/color detection.

Fovea Centralis

Sharpest vision.

Optic Disk

Blind spot.

Vitreous Humor

Maintains shape.

Aqueous Humor

Nourishes anterior chamber.

Lacrimal Gland/Ducts

Tear production and drainage.

Auricle

Collects sound.

Tympanic Membrane

Transmits sound via vibration.

Malleus/Incus/Stapes

Amplify vibrations.

Tensor Tympani/Stapedius

Dampen loud vibrations.

Eustachian Tube

Pressure equalization.

Cochlea

Hearing.

Vestibule/Semicircular Canals

Balance.

Perilymph/Endolymph

Fluid for sound & balance transduction.

General Somatic Efferent (GSE)

Skeletal muscle (e.g., eye, tongue).

General Visceral Efferent (GVE)

Autonomic (parasympathetics).

General Somatic Afferent (GSA)

Sensory from skin/muscles.

General Visceral Afferent (GVA)

Sensory from organs.

Special Somatic Afferent (SSA)

Vision, hearing, balance.

Special Visceral Afferent (SVA)

Smell, taste.

Special Visceral Efferent (SVE)

Motor to pharyngeal arch muscles.