1. Biological Bases of Behavior
AP Psych – Chapter 3
Biological Foundations of Behavior
Alice F. Short
Hilliard Davidson High School

2. Chapter Preview Nervous System Neurons Brain Endocrine System
Damage, Plasticity, and Repair
Genetics and Behavior
Biological Foundations and Health and Wellness

3. Nervous System
Neuroscience…study of the body’s electrochemical communication circuitry
Characteristics of the nervous system
complexity
(metaphor = multitasking)
integration
adaptability (plasticity)
electrochemical transmission

4. Nervous System: Pathways
Afferent Nerves
carry information  spinal cord and brain
Efferent Nerves
carry information  muscles

5. Nervous System: Divisions
The Two Main Divisions of the Nervous System:
1. Central Nervous System (CNS)
brain and spinal cord
2. Peripheral Nervous System (PNS)
somatic nervous system – sensory nerves
muscular activity
autonomic nervous system – internal organs
sympathetic nervous system – arouses
parasympathetic nervous system – calms
Nervous System: Divisions

6. 1. Central Nervous System
1. Central Nervous System (CNS)
brain and spinal cord

7. 2. Peripheral Nervous System
2. Peripheral Nervous System (PNS) – composed of all the sensory and motor nerves
somatic nervous system – sensory nerves
muscular activity
allows you to move in cases of emergency
allows you to move when you want to move
autonomic nervous system – internal organs
sympathetic nervous system – arouses
kicks into overdrive in cases of emergency
parasympathetic nervous system – calms
medication techniques elicit response

8. Nervous System: Cells Neurons Glial Cells information processing
about 100 billion in brain
mirror neurons (in primates) – imitating behaviors of someone else
mimicking the movements of a coach or dancer, etc.
Glial Cells
provide support and nutrition
carries nutrients from blood vessels  neurons

9. Neurons: Structure
neuron – the type of cell that is the basic unit of the nervous system – the nervous system contains over 11 billion neurons
cell body (soma) – contains the nucleus
dendrites – branched appendages that carry information to the cell body
axon – conveys information away from the cell body
myelin sheath – covers the axon and aids in neural transmission

10. Neurons: Structure
dendrite  cell body  axon

11. Neurons: 3 Types
Neuron – the type of cell that is the basic unit of the nervous system – the nervous system contains over 11 billion neurons
sensory neurons are located in the body’s sense organs (for example, the eye, ear, or nose) and send information from these organs to the brain
motor neurons– convey information from the nervous system to the body’s organs, glands, and muscles
interneurons (association neurons) transmit information from one neuron to another within the nervous system

12. Neural Impulse Axons Resting Potential Action Potential
ions/ion channel
negatively/positively charged
semipermeable membrane
polarization
Resting Potential
stable charge of an inactive neuron
a negative charge on the inside of the cell membrane and a positive charge on the outside
Action Potential
depolarization (ion channel opens)
sodium ions flow into the membrane
repolarization
ion exchange sweeps along length of axon
all-or-none principle – intensity of the action potential is not effected by depolarizing and greater levels
once initiated, cannot be stopped

13. Transmission of Nerve Impulse

14. Synapses and Neurotransmitters
Synapse / Synaptic Gap
space between sending axon’s terminal buttons and the receiving dendrite or cell body
the neural message being delivered in a synaptic transmission is carried across the synaptic gap by chemical substances
Synaptic Transmission
electrical impulse is converted into a chemical signal
axon vesicle releases neurotransmitter into gap
dendrite receptor site detects neurotransmitter

15. Synapses and Neurotransmitters
© 2011 The McGraw-Hill Companies, Inc.

16. Neurotransmitters
Neurotransmitters carry information across the synaptic gap to next neuron. (chemical)
Acetylcholine
muscle actions, learning, memory
black widow venom ↑ Ach levels
botox (botulin) ↓ Ach levels
Alzheimer’s disease: ↓ Ach levels
GABA
anxiety: ↓ GABA levels
Glutamate
excitatory
learning & memory
involved in many psychological disorders
Norepinephrine
stress and mania: ↑ norepinephrine levels
depression: ↓ norepinephrine levels
regulates sleep states in conjunction with ACh

17. Neurotransmitters (cont.)
Dopamine
voluntary movement
reward anticipation
stimulant drugs: activate dopamine receptors
Parkinson’s disease: ↓ dopamine levels
schizophrenia: ↑ dopamine levels
Serotonin
regulation of sleep, mood, attention, learning
depression: ↓ serotonin levels
prozac: ↑ serotonin levels
Endorphins
natural opiates
mediate feelings of pleasure and pain
Oxytocin
both a hormone and a neurotransmitter
related to onset of lactation in new mothers
related to attachment/emotional bonds

18. Neurotransmitters Note: Drugs can interfere with neurotransmitters
mimics or enhances NT effects
blocks effects of NT

19. Neural Networks interconnected pathways of nerve cells
integrate sensory input and motor output
take years to develop
a given piece of information embedded in multiple connections between neurons

20. Studying the Brain Brain Lesioning Electrical Recording
naturally occurring or induced
Electrical Recording
electroencephalograph (EEG)
single-unit recording

21. Brain Imaging
X-Ray
CT Scan
PET
MRI
fMRI
TMS

22. Areas of the Brain Hindbrain Midbrain forebrain
Reminder: any part of the brain is a part of the central nervous system (CNS), which is a part of the nervous system in general

23. Areas of the Brain: 1. Hindbrain
Brainstem
medulla – control breathing, regulate reflexes
pons – sleep & arousal
Cerebellum
motor coordination

24. Areas of the Brain: 2. Midbrain
Substantia Nigra
Parkinson disease
Reticular Formation
stereotyped behavior patterns like walking
manipulates neurotransmitters

25. Brain: Structure and Function

26. Areas of the Brain: 3. Forebrain
Limbic System
memory and emotion
amygdala
discrimination of objects needed for survival
emotional awareness and expression
hippocampus
formation and recall of memories
Thalamus
relay station for much sensory information
Basal Ganglia
coordination of voluntary movements
Hypothalamus
eating, drinking, sexual behaviors
regulate body’s internal state
emotion, stress, reward

27. Cerebral Cortex Neocortex: outermost layer Four Lobes:
occipital (vision)
temporal (hearing, language processing, memory)
frontal (intelligence, personality, voluntary muscles)
parietal (spatial location, attention, motor control)

28. Cerebral Cortex

29. Are Brains Wired to Recognize Faces?
prosopagnosia
fusiform face area (FFA)
FFA – specifically for processing faces?

30. Somatosensory, Moor, and Association Cortex
Somatosensoy Cortex (in parietal lobe)
body sensations
Motor Cortex (in frontal lobe)
voluntary movements
Point-to-Point Mapping
Association Cortex (75% of cortex)
not sensory or motor, but associations between

31. Split-Brain Research Corpus Callosum W.J., the Split Brain Patient
Large bundle of axons that connects the two hemispheres of the brain
W.J., the Split Brain Patient

32. Hemispheres of the Cortex
Hemispheric Specialization of Function
left hemisphere
verbal processing, speech, grammar
Broca’s Area
Wernicke’s Area
right hemisphere
spatial perception, visual recognition, emotion
Hemispheres of the Cortex

33. Happy Brains Happiness: Prefrontal Lobe Asymmetry Biofeedback
positive emotional responses
more left prefrontal lobe activity
negative emotional responses
more right prefrontal lobe activity
Biofeedback
Mindfulness (Awareness) Meditation

34. Endocrine System
set of glands that regulate the body by secreting hormones into the bloodstream
hormones = chemical messages
relatively slow communication system
interconnected with the nervous system
pituitary, thyroid, parathyroid, adrenal glands, pancreas, ovaries, testes

35. Brain Damage and Plasticity
Recovery from brain damage depends on
age of the individual
extent of the damage
Repairing the damaged brain
collateral sprouting
substitution of function
neurogenesis
brain tissue grafts

36. Genetics and Behavior chromosomes, genes, and DNA Human Genome Project
dominant-recessive genes principle
molecular genetics
selective breeding
behavior genetics and adoption studies

37. Genes and the Environment
Genotype – genetic heritage + the effects of experience =
Phenotype – observable characteristics
environment alters how genetic traits develop
both physical & psychological characteristics
genetic expression

38. Biological Foundations and Health and Wellness
stressors
…circumstances and events that threaten individuals and/or tax their coping abilities
stress
…our response to those stressors
causes/effects of acute and chronic stress

39. Chapter Summary

40. Chapter Summary
Discuss the nature and basic function of the nervous system.
Explain what neurons are and how they process information.
Identify the brain’s levels and structures and summarize the function of those structures.
Identify the endocrine system and describe how it affects behavior.

41. Chapter Summary Describe the brain’s capacity for recovery and repair.
Explain how genetics increases understanding of behavior.
Describe the role of the biological foundations of human psychology in the body’s stress response.

42. Chapter Summary The Nervous System Brain: Structure and Function
structure and function of the nervous systems
structure of a neruon
electrochemical communication
neurotransmitters and their effects
Brain: Structure and Function
brain imaging techniques
hindbrain, midbrain, forebrain
cerebral lobes and functions

43. Chapter Summary Brain Damage and Plasticity Genetics and Behavior
collateral sprouting, substitution of function, neurogenesis, brain tissue grafts
Genetics and Behavior
“genes v. environment” and adoption studies
Biological Foundations & Health and Wellness
acute and chronic stress