LAB 8- Central and Peripheral Nervous System

Cerebrum

• Right and left cerebral hemispheres

Frontal, parietal, temporal, and occipital lobes

Frontal- front

pariteal- top

temporal- side

Occipital- back

Longitudinal fissure

in the middle of the cerebrum

Gyri and sulci

Gyri- on top of hill

sulci- bottom of hill

Central sulcus

Between frontal and parietal lobes

Lateral sulcus

between temporal and parietal and frontal lobes

Precentral gyrus (primary motor cortex)

a prominent ridge on the surface of the frontal lobe of the brain, located immediately anterior (in front) of the central sulcus

Postcentral gyrus (primary somatosensory cortex)

a prominent fold in the lateral parietal lobe of the human brain that houses the primary somatosensory cortex

Broca’s area

speech production

Wernicke’s area

language comprehension

Cerebral cortex (gray matter) and deeper white matter

Gray matter - top

White matter- bottom

Corpus callosum

a thick C-shaped bundle of roughly 200 to 300 million myelinated nerve fibers (axons) located deep in the center of the brain. It is the largest white matter structure in the human brain

• Its primary function is interhemispheric communication—serving as a high-speed neural bridge that connects the left and right cerebral hemispheres. This allows both sides of the brain to share information and work together as a unified whole.

Diencephalon and associated endocrine structures

Thalamus

Hypothalamus

Pineal gland (part of epithalamus)

Pituitary gland

Thalamus

a paired, egg-shaped structure of gray matter located deep inside the center of the brain within the diencephalon, sitting just above the brainstem and forming the upper walls of the third ventricle

Hypothalamus

a small, almond-sized region located deep at the base of the brain, just below the thalamus and directly above the pituitary gland. It acts as the body's primary control center, linking the nervous system to the endocrine system to maintain internal stability, or homeostasis

Pineal gland (part of epithalamus)

a prominent, cone-shaped endocrine structure that forms a key part of the epithalamus

• bridge the limbic system with other parts of the brain and regulate biological rhythms, emotional responses, and sleep-wake cycles

Pituitary gland

• a small, pea-sized endocrine organ located at the base of the brain, resting in a bony cavity called the sella turcica just behind the bridge of the nose.

• Often called the "master gland," it produces essential hormones and directs other endocrine glands—such as the thyroid, adrenal glands, and gonads—to regulate vital body functions

Brainstem and cerebellum

• Midbrain

• Pons

• Medulla oblogata

• Cerebellum, cerebellar hemispheres

• Cerebellar cortex and arbor vitae

Midbrain

Pons

Medulla oblongata

Cerebellum , cerebellar hemispheres

Cerebellar cortex and arbor vitae

Ventricles and cerebrospinal fluid

• Right and left lateral ventricles

• Third Ventricle

• Inteventricular foramina

• Cerebral aqueduct

• Fourth ventricle

• Chororid plexus (site of CSF production)

Right and left lateral ventricles

on right and left side of the brain

Third ventricle

Interventricular foramina

Cerebral aqueduct

Fourth ventricle

Choroid plexus (site at certain levels)

Spinal cord cross section

□ Gray matter and white matter

□ Dorsal (posterior) horn

□ Ventral (anterior) horn

□ Lateral horn (present at certain levels)

□ Central canal

□ Dorsal, lateral and ventral white matter columns

Gray matter and white matter

Dorsal (posterior) horn

Ventral (anterior) horn

Lateral horn (present at certain levels)

Central canal

Dorsal, lateral, and ventral white matter columns

Spinal nerve roots and branches

□ Dorsal root (sensory)

□ Dorsal root ganglion

□ Ventral root (motor)

□ Spinal nerve (mixed)

□ Dorsal ramus (mixed)

□ Ventral ramus (mixed)

Dorsal root

sensory

Dorsal ganglion

Ventral root

motor

Spinal nerve

mixed

dorsal ramus

mixed

Ventral ramus

mixed

Cranial nerves

I

olfactory

II

Optic

III

Oculomotor

IV

Trochlear

V

Trigeminal

VI

Abducens

VII

Facial

VIII

Vestibulocochlear

IX

Glossopharyngeal

X

Vagus

XI

Accessory

XII

Hypoglossal

Cervical plexus

Phrenic nerve

Brachial plexus

□ Axillary nerve

□ Radial nerve

□ Median nerve

□ Ulnar nerve

Lumbar plexus

□ Femoral nerve

□ Obturator nerve

Sacral plexus

• Sciatic nerve

• Tibial nerve

• Common fibular nerve