1. Unit 3: Biological Psychology
CHS AP Psychology
Unit 3: Biological Psychology
Essential Task 3-5b:Describe the subdivisions and functions of the peripheral nervous system:
A. Somatic Nervous System
B. Autonomic Nervous System
i. Sympathetic Nervous System (Fight or Flight)
ii. Parasympathetic Nervous System (Rest and Digest)
Logo Green is R=8 G=138 B= Blue is R= 0 G=110 B=184
Border Grey is R=74 G=69 B=64

3. The Central Nervous System
The Brain
The Spinal Cord

4. The Spinal Cord
Complex cable of nerves that connects brain to rest of the body
Carries motor impulses from the brain to internal organs and muscles
Carries sensory information from extremities and internal organs to the brain
400,000 people a year in US either partial or complete paralysis.

5. The Spinal Cord
The spinal cord controls some protective reflex movements without any input from the brain

6. The Somatic Nervous System
Consists of neurons that communicate between the body and the brain
Motor Neurons
Neurons that carry messages from the spinal cord (through interneurons) or brain to muscles and glands

7. The Autonomic Nervous System
Sympathetic division
Most active when you are angry, afraid, or aroused
Increases heart rate and breathing
Stops digestion
“Fight-or-flight”

8. SNS = Evolutionary Byproduct

9. What “fear” looks like… (Taken in a Haunted House)
A Sympathetic Nervous System (SNS) Response

10. Hold me!

11. Congo line of fear

12. Even Flannel Bros have an SNS response

13. The “I’m not really here to protect you; I just happen to be in front” response.

20. Fight, Flight and “Freeze”?

27. The pupils don’t just dilate for some people. The eyes widen, too!

33. The Autonomic Nervous System
Parasympathetic division
Calms body
Produces effects opposite to those of the sympathetic division
Reduces heart rate and breathing
Restores digestion
“Rest and Digest”

34. The Hypothalamus Has Central Control of the ANS
When someone experiences a stressful event, the amygdala, an area of the brain that contributes to emotional processing, sends a distress signal to the hypothalamus.
This area of the brain functions like a command center, communicating with the rest of the body through the nervous system so that the person has the energy to fight or flee.
The hypothalamus is involved in the coordination of ANS responses
One section of the hypothalamus seems to control many of the "fight or flight" responses; another section favors "rest and digest" activities