Nervous System A &P of the Central

A &P of the Central Nervous System

3 Layers- superficial to deep, pg 449

1. Gray matter2. White matter3. Basal Nuclei: aka basal ganglia

Gray vs. White Matter

Parts of the NEURON

Grey: cell bodies, dendrites

White: axon, myelinated fibers

The Brain

Cerebral Hemispheres: superior part of brain made up of 5 lobes

Frontal, Parietal, Occipital, Temporal lobes and insula

*insula is covered by other lobes

Gyri vs SulciGyri: (gyrus=1) elevated ridges of neural tissue that mark the entire surface of the cerebral hemispheres

Sulci: (sulcus=1) Shallow grooves; a fissure are very deep sulcus separating major regions

Knob: a protruding ‘knob-like’ shape indicate a talent

CEREBRAL CORTEX CEO

3 parts- Motor, Sensory & Association

Anatomy: grey matter (cell body, dendrite, glial cell, blood vessel)

Physiology:

● conscious mind● communicate● memory● comprehend

Motor Areas- Anatomy

• Posterior part of the frontal lobes– primary motor cortex fig 12.9, pg 438– premotor cortex– Broca’s area– frontal eye field

Motor Areas- Physiology

• controls voluntary movement by organizing all of the skeletal muscles involved in 1 action

• controls learned motor skills (typing)• speech • controls extrinsic eye muscles

Homeostatic Imbalance of Motor Area

• Primary motor cortex: paralysis• Premotor cortex: slower speed in

executing task

Sensory Areas

• Anatomy: Parietal,temporal, occipital lobes and insular– visual - gustatory – auditory - visceral– olfactory - vestibular

• Physiology: conscious awareness of sensation

Homeostatic Imbalance of Sensory Area

• primary visual cortex: blindness

• visual association area: lack of comprehension

Association Areas

• Anatomy: prefrontal cortex, temporal lobe, parahippocampal gyrus

• Physiology: comprehend the sensory input, integrates and respond...HOMEOSTASIS

Homeostatic Imbalance- Association Areas

• Tumors/lesions – Anterior:loss of judgement,

attentiveness, inhibitions– Posterior: loss of awareness of

self (personal hygiene)

Diencephalon pg. 449

Thalamus: receives sensory info to cerebral cortex

Hypothalamus: body temp, Autonomic Nervous System

Epithalamus: secretes melatonin

Brain Stem pg.449

Midbrain

Pons: Controls breathing

Medulla Oblongata: vomit, hiccup, swallow, cough, sneeze

Cerebellum pg 451

Controls balance in the inner ear, eye and skeletal muscles

Protecting the Brain, pg460

1. Meninges: a. Dura Materb. Arachnoidc. Pia Mater

2. Cerebrospinal fluid

3. Blood-Brain Barrier

Traumatic Brain Injuries, pg.464

Concussion

Contusion

Subdural hemorrhage

Cerebral edema

1. Concussion

Concussion- temporary change in brain function

*blow to the head (dizziness)

*cumulatively damaging

2. Contusion

• more serious concussion• bruising on the brain• brain stem → coma

3. Subdural/Subarachnoid Hemorrhage

• bleeding from ruptured vessels into those spaces

• blood accumulates → > pressure to push brain into skull

• >pressure on brain stem = loss of heart rate, bp & respiration

Treating subdural/subarachnoid hemorrahage

• surgical removal of hematoma (blood mass) & repair ruptured vein

4. Cerebral Edema

• swelling of the brain• intracranial pressure = loss of blood

flow (no O2)

CerebroVascular Accidents: are strokes that are the most

common neurological disorder

Ischemia: loss of blood flow (deficient oxygen and

nutrient delivery to cells) caused by a blood clot

Transient Ischemic Attacks: (TIA) are temporary strokes; aka WARNING STROKES

Degenerative Brain Disorders

Alzheimer’s Disease: degenerative progression of dementia; brain cells die causing it to shrink, especially the hippocampus.

Parkinson’s Disease: diagnosed in 50’s-60’s, results from the degeneration of the dopamine-releasing neurons