CENTRAL NERVOUS SYSTEM, SPINAL NERVES, CRANIAL NERVES

CNS – Central Nervous System

Spinal nerves 31 pairs

Cranial nerves 12 pairs

Meninges – protection of the Spinal Cord Dura Mater Subdural space Arachnoid layer Sub-arachnoid space Pia mater

Protection Cerebrospinal fluid

Protection Vertebrae of Vertebral Column

Function of Spinal cord Transport nerve impulses from senses to brain Transport nerve impulses from brain to muscles or glands

Sensory/Afferent neuron

Motor/Efferent neuron

Reflex arc

Lumbar Puncture

L 3, L 4, L 5

Spinal Nerves 31 pairs

Cauda Equina Horse's tail

Anatomy of Spinal nerves

Plexuses

General Information Re the Brain – question C 2 2% of body weight Receives about 20% of body’s blood supply Circle of Willis – diagram 21.19 text Lack of Oxygen 1 – 2 minutes impairs neuron function Over 4 minutes permanent brain damage Brain stores little if any glucose Must have constant supply Lack of enough glucose Mental confusion Dizziness Convulsions Loss of consciousness

Pathway of CSF

Brain Stem

Pons Bridge

Medulla Medulla Pathway for all ascending and descending tracts of white matter Sensory and motor

Diencephalon Thalamus Hypothalamus Sensory Autonomic Pituitary gland Emotions Behavior Thirst/eating Body temp Circadian rhythm

Anatomy of Brain

Functions of white matter tracts in Cerebrum Associative tracts Nerve impulses w/in same hemisphere Commissural tracts NI from left to right and right to left hemispheres Projection tracts Cerebrum to thalamus, brain stem, spinal cord

Basal ganglia Deep within the Cerebrum Movement Damage to BG is Parkinson’s

Ventricles Cavities in the brain that produce and contain Cerebrospinal Fluid Pg. 243 text

Limbic system Question D7 a “Emotional Brain” Pg. 495 text Olfaction Memory Primary role in range of emotions Pain Pleasure Docility Affection Anger

Functional areas of the brain

Cranial Nerves

Table E 2 Olfactory Nerve # I Function Sense of smell

Optic Nerve # II Function Sight – not pain or temperature of eye

Oculomotor Nerve # III Function Proprioception Movement of muscles in and around eye

Trochlear Nerve # IV Function Proprioception Movement eyelids

Trigeminal Nerve # V Function Touch, pain, temp sensations on face Chewing

Abducens Nerve # VI Function Stimulates lateral rectus to abduct eye Proprioception

Facial Nerve # VII Function Facial expression, taste, proprioception

Vestibulocochlear Nerve # VII Function Hearing, equilibrium

Glossopharyngeal Nerve # IX Function Taste, swallowing, monitors O2 and CO2 in blood, speech

Vagus Nerve # X Function Taste, swallowing, coughing, voice, organs of GI tract, HR

Accessory Nerve # XI Function Proprioception, swallowing, movement of head and shoulders

Hypoglossal Nerve # XII Function Motor and sensory fibers of the muscles of tongue

Common Disorders Hemiplegia Monoplegia Paraplegia Quadriplegia Paralysis of arm, leg, trunk on one side of body Paralysis of one extremity only Paralysis of both legs Paralysis of both arms and legs

CVA or TIA CVA TIA Cerebrovascular accident Stroke Occurs when blood vessel to brain is plugged or blocked by a blood clot TIA Transient Ischemic attack Mini-stroke Occurs when blood supply to brain is briefly interrupted

Shingles Neuritis Neuralgia Encephalitis Anesthesia Analgesia