1. Psychology Chapter 6: Body and Behavior

2. The Nervous System: The Basic Structure
How the nervous system works
It never rests
Controls our emotions, movements, thinking and behavior
It is divided into 2 parts (Figure 6.1)
Central Nervous System (CNS)
Consists of the brain and spinal cord
Peripheral Nervous System (PNS)
Smaller Branches of nerves that reach other parts of the body from the spinal cord (thickness of a pencil)
Take information from the organs to the CNS and from the CNS back to the organs
Each is protected by something
Brain by the skull and several layers of sheathing
Spinal cord by the vertebrae
Peripheral nerves by layers of sheathing

3. The Nervous System cont.
Neurons (Figure 6.2) Photos and video
Nerves are long, thin cells called neurons
Messages travel along these
Neurons can fire (or transmit signals) hundreds of times a minute
Neurons have three basic parts
The cell body
Contains the nucleus and produces the energy needed to fuel neuron activity
Dendrites
Short, thin fibers that stick out from the cell body and receive impulses from other neurons and send them to the cell body
Axons
Long fiber that carries the impulses away from the cell body toward the dendrites of the next neuron
Other structures
Myelin Sheath – white, fatty substance insulates and protects the axon
If it is destroyed, behavior of the person can be erratic and uncoordinated (as in MS)
Speeds the transmission of impulses
Axon terminals – branch out from the end of the axon, they are positioned directly opposite of the dendrite.

4. Neuron Diagram

5. Connection between Neurons
Neuron connection (Figure 6.3)
Synapse – the space between the axon terminals of one neuron and the dendrites of another neuron.

6. Neurons/Synapse cont. Synapse:
This is the junction or connection between neurons
Neurons transmit impulses or messages across this space using neurotransmitters
c) Neurotransmitters – are chemicals that either excite the next neuron or stop it from transmitting
There are different types of neurotransmitters
Norepinephrine – involved in memory or learning
Endorphin – inhibits pain
Acetylocholine – involved in movement and memory (associated with paralysis and Alzheimer’s)
Dopamine – involved in learning, emotional arousal and movement (too much is associated with schizophrenia and too little with Parkinson’s)
Serotonin (an undersupply linked with a lack of norepinephrine is associated with depression)

7. Nervous System cont. Voluntary and Involuntary Activities
Somatic Nervous System (SNS) – refers to the part of the peripheral nervous system that controls voluntary activities
Body making a response to impulses from the nerves like turning a page in a book
Autonomic Nervous System (ANS) – refers to the part of nervous system that controls involuntary activities, or those that occur automatically
Your heartbeat, breathing, stomach activity
Has two parts
Sympathetic nervous system – prepares the body for dealing with emergencies or strenuous activities
Speeds up the heart to hasten the supply of blood and nutrients to body tissues
Parasympathetic nervous system – works to conserve energy and to enhance the body’s ability to recover from strenuous activity
Reduces heart rate and blood pressure to bring the body back to its resting state

8. Nervous System Diagram
Section 1 Review

9. Studying the Brain

10. Studying the Brain cont.
The Brain is composed of 3 parts
The Hindbrain
Located at the rear base of the skull
Involved in the most basic processes of life
Includes:
The cerebellum
The medulla
The pons

11. Studying the Brain cont.
2. The Midbrain
Integrates sensory information
Alerts the rest of the brain to incoming signals and is involved in the sleep/wake cycle

12. Studying the Brain Cont…
3. The Forebrain
All information from the senses, minus smell, come through the thalamus
Controls: hunger, thirst, sexual behavior, reaction to temperature
Higher level thinking processes
Ability to learn and store complex and abstract information; project thinking into the future
See, read and understand
Regulates emotions and motivations
Includes:
Thalamus
Cerebral Cortex
Cerebrum
Limbric System
Hypothalamus, amygdala (violent emotions and fear), thalamus and hippocampus (memory)

13. Studying the Brain cont.
Lobes of the Brain
Cerebrum is split into 2 sides or hemispheres
Connected by the corpus callosum

14. Studying the Brain cont.
2. Occipital Lobe
Where visual signals are processed
Damage may cause visual impairment
3. Parietal Lobe
Receives and deals with information from all the senses
4. Temporal Lobe
Concerns: hearing, memory, emotion and thinking
5. Frontal Lobe
Concerned with organization, planning and creative thinking
6. Somatosensory Cortex
Receives information from the touch sensors
7. Motor Cortex
Sends information to control body movement

15. Studying the Brain cont.
The Hemispheres
Each work together to compliment and help each other
Corpus callosum carries information back and forth between the hemispheres and the lobes (each of the 4 lobes are present in both hemispheres)
3. Left Hemisphere
Controls movement on the right side of the body
Where speech is located (in most people)
Specialized for mathematical ability, calculation and logic
4. Right Hemisphere
Controls the left side of the body
Adept at visual and spatial relations
Perceptual tasks
Recognizing patterns (music and art)
Creativity and intuition

16. Studying the Brain cont.
Split Brain Operations
Usually done to those with severe seizures
2. Cuts the corpus callosum
Lowers the severity and number of seizures
Information cannot cross into other spheres
Person with a split brain can hold a ball in their right hand and say it was a ball, but not holding it in their left hand.
Shows how unique and the specialize functions and skills of each hemisphere
Remained practically unchanged in intelligence, emotion and personality

17. Studying the Brain cont.
How do Psychologists study the brain?
1. Recording
Putting electrodes into the brain to record electrical activity
EEG – electroencephalograph. Millions and millions of neurons can be studied at one time with an EEG attached to the scalp
Shows brain waves which show the amount of neural activity
2. Stimulation
Fires off neurons by electricity
Can show what areas of the brain do
Memories
Songs
Smells
3. Lesions
Cutting or destroying areas of healthy brain tissue and studying the results
4. Accidents
Studying the results of accidents and medical issues
Phineas Gage
Coma patients
Traumatic head injuries

18. Studying the Brain cont.
5. Images
CAT (Computerized Axial Tomography) scans
Transfers the amount of radiation absorbed by the density of brain tissue into a 3 dimensional view of the brain
PET (Positron Emission Tomography) scans
Shows the absence or presence state of activity in an area of the brain through radioactive dye
MRI (Magnetic Resonance Imaging)
Ability to study both activity and brain structure
Uses both CAT and PET scanning capabilities
fMRI (Functional Magnetic Resonance Imaging)
New, can see the blow flow into active areas to determine activity and functionality
Section 2 Review

19. The Endocrine System
Endocrine system – sends chemical messages to and from the brain
1. Chemical messages used to send are called hormones
Produced by the glands and send by blood and other bodily fluids
Once in the blood stream, they can only be received by the specific organs that they can influence
Ductless, they don’t need pores or ducts (small holes) to release to an organ (sweat glands, tear glands, salivary glands)
Various effects on behavior and moods
Growth of organs, muscles and bones
2. Pituitary Gland
Directed by the hypothalamus
Secretes a large number of hormones, many of which control the output of other hormones
Corrects imbalances of hormones in the body
Keeps metabolism in check despite outside influences
Control growth and reproduction

20. The Endocrine System cont.
3. Thyroid Gland
Produces thyroxine
Stimulates chemical reactions for all tissues
Too little, people feel lazy; too much people lose weight, sleep too much and are overactive
4. Adrenal Gland
Become active when someone is angry or frightened
Release Epinephrine (adrenaline) and norepinephrine (nor adrenaline)
Speed up heart rate and breathing; heighten emotion; extra energy
Secret cortical steroids
Help muscle develop and cause the liver to release stored sugar for extra energy in emergencies

21. The Endocrine System cont.
5. Sex Glands
2 Types
Testes – male
Produce sperm and testosterone (sex hormone)
Ovaries – females
Produce eggs and estrogen and progesterone
Testosterone
Important to physical development of males during the prenatal and adolescence periods
Prenatal – helps decide the sex of the fetus
Adolescence – development of bone and muscle, male sex characteristics
Estrogen and progesterone
Development of the female sex characteristics
Regulate the reproductive cycle
Variances of the hormones cause the symptoms of PMS
6. Hormones vs. Neurotransmitters Difference
When the chemical is released right beside a cell to excite or inhibit it, it is a neurotransmitter
When a chemical is released into the blood, it is a hormone
Section 3 Review

22. Heredity and the Environment
1. Is human behavior instinctive (due to heredity) or learned (environment)
Heredity is the genetic transmission of characteristics from parents to their offspring
2. Nature vs. Nurture
a. Genes and behavior
Reproduced and passed onto children
Occur through their role in building and modifying the physical structures of the body
b. Twin studies
Identical twins – develop from the same single, fertilized egg, thus sharing the same genes
Fraternal twins – develop from 2 fertilized eggs, not more similar genes than brothers or sisters
One study showed that twins growing up apart from one another showed similar behaviors, despite different socials, cultural and economic backgrounds
Suggests heredity may contribute to behaviors once thought more environment in nature
It is possible though to alter the environment that genes operate in thus changes these “hereditary” ideas

23. Heredity and the Environment
Section 4 Review
Chapter 6 Study Guide
Chapter 6 Review Quiz
Chapter 6 Test