1. Nervous System Two major divisions Central Nervous System (CNS)
brain and spinal cord
2. Peripheral Nervous
System
motor and sensory neurons around the body

2. Peripheral Nervous System
Two Divisions
Somatic -
relationship with the external environment
sends info from sensory detectors to brain
Autonomic
involved in regulation internal functions
digestion, respiration, excretion, etc.

3. Central Nervous System

4. Sagittal Section of Brain
cerebrum
Corpus callosum
cerebellum
Medulla oblongata
pons

5. Vision center – Occipital
Touch, feeling, pain, temperature – Parietal
Reasoning, planning, parts of speech, problem-solving – Frontal
Speech, remembering scenes, talks – Temporal
Movement, balance & muscle tone – Cerebellum
Cardiac, respiratory,life functions – Brain Stem
Emotion & Motivation-Limbic System

6. Sulcus and Gyrus The Sulcus are the grooves in the brain tissue
The Gyrus are the “hills” in the brain tissue
These allow for greater surface area for the brain = more brain power!

8. Neuron (Nerve Cell) Myelin Sheath Cell Body ----Nucleus Axon Dendrites
Made by Schwann Cells increases speed of neural signals down the axon
Cell Body ----Nucleus
Axon
Carry messages away from the cell body to other neurons
Dendrites
Carry messages to the cell body

9. Types of Neurons Sensory Neurons Interneurons Motor neurons
Carry the impulse to the spinal cord
Travels the length of the arm to the spinal cord
Interneurons
Impulse is transmitted to the brain and the motor neurons via synapses
Travels to the brain to register pain and out to the finger
Motor neurons
Sends the processed information back to finger
Carries impulse to the effector cells in the fingers, hand and arm

10. Nerve Impulses
120 meters per second = speed at which impulses travel in the body.
Synapse – gap between two neurons (axon and dendrite)
Impulse travels from one neuron to the next by sending chemicals (neurotransmitters) across a gap to activate the next neuron.

12. ___3___ Membrane depolarizes to threshold
___3___ Membrane depolarizes to threshold. Voltage-gated Na+ channels open and Na+ enters the cell.
___8___ The cell returns to resting ion permeability and resting membrane potential.
___6___ K+ moves from cell to extracellular fluid (the cell is repolarizing).
___4____ Rapid Na+ entry depolarizes cell.
__1, 9__ Resting membrane potential.
___5___ Na+ channels close and slower K+ channels open.
___2____ Depolarizing stimulus.
___7___ K+ channels remain open and additional K+ leaves the cell, hyperpolarizing it.

13. Reflex Arc Hand touches open flame or hot burner
Impulse travels to spinal cord
Impulse sent to brain and back to hand.
Hand pulls back before pain is registered by brain 3. 2. 1. 4.

14. Involuntary Reflex Arcs . . . .
Use only spinal cord
Do not go to the brain
Examples:
knee jerk, eye blink,hot stove pull back

15. Reflex arc pathway . . . R S I M receptor receives the stimuli
sensory neuron passes the impulse on I
interneuron at the spinal cord processes M
motor neuron acts

16. Know Your Neurological Disorders!
Multiple Sclerosis
Alzheimer’s
Epilepsy
Parkinson’s
Amytrophic Lateral Sclerosis
Huntington’s
CIPA
Fibromyalgia
Kennedy’s
Creutzfeld-Jakob