1. Central Nervous System

2. Divisions of the Brain Brainstem Medulla oblongata Pons Midbrain
extension of spinal cord
Contains the cardiac, respiratory and vasomotor centers (control heartbeat, blood vessel diameter)
Consists of white and gray matter intermingled
Pons
Midbrain

3. Diencephalon Small, located above midbrain, below cerebrum
Consists of 2 major structures: hypothalmus and thalmus
Hypothamus:
Pituitary gland is an extension of hypothalmus
Major control over most major organs
Make hormones secreted by pituitary gland
Secrete releasing hormones into blood to the anterior pituitary gland
Helps regulate water balance, body temperature, sleep cycles and appetite and many emotions

4. Diencephalon Thalmus Dumb bell shaped gray matter, above hypothalmus
Axons go into cerebellum
Helps produce sensations, associates sensations with emotions and plays a role in the arousal or alerting mechanism

5. Cerebellum Second largest part of human brain
Arbor vitae – tree of life, gray matter on outside, white matter inside
Produce smooth, coordinated movements, maintain equilibrium and sustain normal postures.

6. cerebrum Largest and upper most part of brain
Ridges – convolutions or gyri
Grooves – sulci, deep grooves – fissures
Longitudinal fissure – divides into left and right
Find also the central sulcus, lateral fissure
Corpus callosum – connects left and right hemisphere of the brain

7. cerebrum 4 major lobes of the brain named for bones
Frontal, Occipital, Temporal, parietal
Cerebral cortex – gray matter, surface of cerebrum
White matter (tracts) makes up most of cerebrum
exception is basal ganglia (produce automatic movements and posture, ex. Parkinson disease

8. Brain disorders
Cerebrovascular accident (CVA) – stroke – hemorrhage or cessation of blood flow through vessels in brain, neurons die
If damage occurs in a motor control section of brain, movement ceases
Cerebral palsy – damage to brain tissue
Prenatal infections, trauma to the head before, during, after birth, reduced oxygen to brain
Spastic paralysis – involuntary contractions of affected muscles
Hemiplegia – 1 side of body
Paraplegia – both legs
Triplegia – both legs, 1 arm
Quadriplegia – all 4 appendages

9. Degenerative brain disorders
Destruction of neurons in the brain
Affects memory, attention span, intellectual capacity, personality and motor control = dementia
Alzheimer Disease (AD) – lesions on cerebral cortex
Huntington disease (HD) – chorea – involutary purposeless movements

10. Seizure Seizure – sudden bursts of abnormal neuron activity
Range from mild to severe
Epilepsy – recurring or chronic seizures
Can be caused by tumors, trauma, or chemical imbalances, most idiopathic
Medications block neurotransmitters in affected areas of the brain.

11. Spinal cord Average of 17 – 18 inches
From occipital bone to L1 vertebrae
core is made up of gray matter
Outer part is white matter – spinal tracts

12. Spinal cord 2 way conduction Primary reflex center
Ascending tracts – to brain
Descending tracts – from the brain
Primary reflex center
Cut in the spinal cord results in no communication
Anesthesia – loss of sensation
Paralysis – loss of the ability to make voluntary movements

13. Coverings Meninges – touch, fluid-containing membrane 3 layers
Dura mater – tough outer layer
Pia mater – innermost membrane, covers spinal cord
Arachnoid mater – between dura and pia mater, cob web like
Meningitis – infection or inflammation of meninges

14. Fluids
Cerebrospinal fluid (CSF) – fills subarachnoid spaces in brain and spinal cord and ventricles in brain
2 lateral ventricles and third ventricle
CSF is continuously begin made from fluid filtering out of choroid plexus and into ventricles and continues to circulate around the brain and spinal cord
Hydrocephalus – water on the brain – accumulation of CSF in ventricles