CNS
Brain and spinal cord
PNS
Connects CNS to other body parts
2 divisions of PNS
- Somatic NS
2. Autonomic NS
Somatic NS
•voluntary or involuntary
•what does it include
•examples
- Voluntary actions
- sensory and motor nerves
- walking upstairs
Autonomic NS
•voluntary or involuntary
• 2 divisions
•involuntary
- Parasympathetic
- sympathetic
Each neuron develops approx. ____ connections
10,000
What does it mean when neurons “fire”
They carry messages to the next neuron
6 different neurotransmitters
- Acetylcholine
- Dopamine
- GABA
- Glutamate
- Norepinephrine
- Seratonin
Acetylcholine
•function
•ACH deficit leads to
- stimulates muscles, learning and memory
* ACH deficit -> Alzheimer’s
Dopamine
•function
•levels in Schizophrenia; levels in parkinson’s
- influences sleep, mood, attention, control of voluntary movement
- high in S, low in P
GABA
•function
•what does low GABA lead to
- Stops other neurons from firing
* higher anxiety
Glutamate
•function
•what does high glutamate lead to
- excites neurons involved in learning and memory
* migraine headaches
Norepinephrine
•function
•Low levels lead to
•high levels lead to
- Stops neurons from sending info in CNS
- depression
- agitation, mania (bipolar)
Seratonin
•function
•Low levels lead to
- regulates sleep, mood, attention and learning
* depression, Prozac increases seratonin
Cerebral cortex
- wrinkled outer layer
- split into right and left hemispheres
- where most of cognition happens
4 divisions of cerebral cortex
- Occipital
- Temporal
- Parietal
- Frontal
Occipital lobes
- Translates info from eyes
- interprets color, shape, movement in environment
- visual memory
Temporal lobes
- translates info from ears
- interprets sounds and pressure changes
- auditory memory and language
Parietal lobes
- interprets info on balance and environment cues
- determines location in space
- directs attention and movement
Frontal lobes
- interprets all sensory input
- location of intelligence and personality
- directs movement
All-or-nothing principle
once the electrical impulse reaches a certain level of intensity, it fires and moves all the way down the axon without losing an intensity