1. Chapter 3: Biopsychology

2. 3.1 Human Genetics Evolution by Natural Selection (1859)
Charles Darwin’s theory
Organisms that are best adapted to their environment are more likely to survive, reproduce, and pass on genetic information

3. Genetic Variation Genotype: An individual’s genetic makeup
Phenotype: An individual’s inherited physical traits

4. Epigenetics: Gene-Environment Interactions
Studies of identical and fraternal twins have helped us learn about the influence of environmental factors on the expression of our genes, or epigenetics.

5. Nervous system The body’s electrochemical communication circuitry
Made up of:
nerve cells (neurons)— conduct impulses
and glial cells (glia)— support cells

6. Structure of a neuron— 4 main parts
Cell body (soma): Keeps neuron alive and determines whether it will send a message
Dendrites: Receive information from other neurons and transmit toward the cell body
Axon: Extending fiber that conducts impulses away from the cell body to other cells
Terminal buttons: Area where chemical messengers (neurotransmitters) are secreted by the neuron

7. How neurons communicate
Myelin sheath wraps around the axon of some neurons and speeds neural transmission
Neurotransmitter enters synapse (gap between neurons)
Neurotransmitter temporarily binds to receptors—sites on receiving neuron’s membrane

8. Action Potential
The electrical signal that travels down the axon, from the cell body to the terminal buttons, resulting in a release of neurotransmitter into the synapse

9. 3.3 Parts of the Nervous System
Functions of the nervous system include:
Gathering and processing information
Producing responses to stimuli
Coordinating workings of different cells

10. Human Nervous System Central Nervous System Peripheral Nervous System
Brain
Housed in the skull
Approx. 3 lbs
Mostly comprised of neurons and glia
Spinal cord
Comprised of neurons and supportive tissue
Runs from base of brain down center of back
Protected by spinal column
Peripheral Nervous System
Somatic Nervous System
Controls skeletal muscles
Allows for voluntary movement
Autonomic Nervous System
Controls muscles of internal organs
Regulates blood vessels, glands, internal organs

11. Autonomic Nervous System
Sympathetic Nervous System
*Arouses the body
*Uses energy
*”Fight or flight” response
Parasympathetic Nervous System
*Calms the body
*Conserves energy

12. Biofeedback
A method for gaining control over the autonomic nervous system
One learns using feedback from equipment that measures biological functions (e.g., body temperature, blood pressure, sweat response, muscle tension, brain activity)

13. Brain stem
Medulla Responsible for certain automatic functions such as breathing and heart rate Pons Involved in sleeping, waking, and dreaming

14. Cerebellum Regulates movement and balance
Involved in remembering simple skills and acquired reflexes
Plays a part in:
Analyzing sensory info
Solving problems

15. Thalamus
Relays sensory messages to the cerebral cortex Includes all sensory messages except those from olfactory bulb (smell)

16. Limbic system
A group of brain areas involved in emotional reactions, motivated behavior, and memory— includes:
Amygdala
Hippocampus
Hypothalamus

17. Amygdala Responsible for Arousal Regulation of emotion
Initial emotional
response to sensory
information

18. Hippocampus Responsible for storage of new information in memory
Enables us to form spatial memories for navigating the environment

19. Hypothalamus Involved in: Emotions Drives vital to survival Fear
Hunger
Thirst
Reproduction
Feeling rewarded
Regulating autonomic nervous system

20. Pituitary gland
Small endocrine gland which releases hormones and regulates other endocrine glands
Works in conjunction with hypothalamus

21. The endocrine system
Endocrine glands release hormones into the bloodstream…
…Hormones regulate growth,
metabolism, sexual development
and behavior, and other functions.

22. The cerebral cortex Largest brain structure
In charge of most sensory, motor, and cognitive processes
Divided into two halves, called hemispheres

23. Lobes of the cerebral cortex
Occipital lobes Vision (visual cortex) Parietal lobes Body sensation (somatosensory cortex) Temporal lobes Memory, perception, emotion, hearing (auditory cortex) Frontal lobes Emotion, planning, creative thinking, personality, and movement (motor cortex)

24. Corpus callosum
Millions of myelinated axons connecting the brain’s hemispheres
Provides a pathway for communication
If surgically severed to treat epilepsy, resulting in a “split-brain” condition, the hemispheres cannot communicate directly

25. Lateralization
Specialization of the two cerebral hemispheres for particular operations

26. Motor control and the hemispheres
Left hemisphere controls right side of body
Right hemisphere controls left side of body

27. Broca’s area
Left hemisphere controls speech production

28. Plasticity
The brain’s ability to change and adapt in response to experience
Reorganizing or growing new neural connections

29. Brain imaging: Electroencephalography(EEG)
A recording of neural activity detected by electrodes placed on the scalp

30. Brain imaging: Computerized Tomography (CT Scan)
Multiple X-rays are combined to show cross-sections of brain tissue

31. Brain imaging: Positron Emission Tomography (PET Scan)
A method for analyzing biochemical activity in the brain, using injections of a glucose-like substance containing a radioactive element
Active areas have increased blood flow.
Sensors detect radioactivity.
Different tasks show distinct activity patterns.

32. Brain imaging: Magnetic Resonance Imaging (MRI)
Method for studying body and brain tissue
Magnetic fields allow for detection of energy/radio waves.
Computer calculates tissue density from radio waves.
Provides clear 3D images
fMRI provides pictures of activity by measuring blood flow