Transcript Chapter 2

Chapter 3
Biopsychology and the
Foundations of Neuroscience
“If I Only Had A Brain” – Wizard of Oz
What is Biopsychology?
Biopsychology –
The specialty in psychology that studies
the interaction of biology, behavior, and
the environment
Neuroscience –
Interdisciplinary field that focuses on the
brain and its role in psychological
processes
How Are Genes and
Behavior Linked?
Evolution has fundamentally
shaped psychological
processes because it favors
genetic variations that
produce adaptive behavior
How Are Genes and
Behavior Linked?
Innate –
Inborn; present at birth; part of the
organism’s biological heritage
Evolution –
The gradual process of biological change
that occurs in a species as it adapts to its
environment
Evolution and Natural Selection
Natural selection –
The driving force behind evolution, by
which the environment “selects” the fittest
organisms
How Natural Selection Works
Environmental pressure
(changes in the environment)
Competition
(for resources)
Selection of fittest phenotype
(from among a variety of phenotypes)
Reproductive success
(genotype corresponding to fittest
phenotypes passed to next generation)
Frequency of that genotype increases
(in next generation)
Genes and Inheritance
Genotype –
An organism’s genetic makeup
Phenotype –
An organism’s observable physical
characteristics
Genes and Inheritance
Mutations –
Genetic variations, which occur
randomly, especially during the
recombination of chromosomes in sexual
reproduction
Every cell in your body is made up of chromosomes,
which are made up of genes, which are made up of
strands of DNA.
Chromosomes, Genes, and DNA
Every cell in your body is made up of chromosomes, which
are made up of genes, which are made up of strands of
DNA.
1. DNA –
A long, complex molecule that encodes
genetic characteristics
2. Genes –
The functional units of a chromosome
Composed of nucleotides
Chromosomes, Genes, and DNA
3. Chromosomes –
Tightly coiled threadlike structures along
which the genes are organized
Sex chromosomes –
The X and Y chromosomes that
determine our physical sex characteristics
Genetic Explanations for
Psychological Processes
Genes influence our psychological
characteristics as well as our physical
traits
Choosing Your Children’s Genes
• Scientists already have the ability to control and alter
genes of animals and clone animals.
• Currently, scientists are looking into how to use this
information in order to treat disorders like Parkinson’s,
heart disease, Down Syndrome, etc.
• How can stem cells be used to help with these
disorders?
• What are the ethical issues that surround this topic?
• If we are going to “pick” the best traits, who is to
decide what is “the best?”
How Does the Body
Communicate Internally?
The body’s two
communication systems, the
nervous system and the
endocrine system, both use
chemical messengers to
communicate with targets
throughout the body
The Neuron
Types of Neurons
Sensory neurons (carry messages from
sense receptors towards the CNS)
Motor neurons (carry messages from
CNS toward muscles and glands)
Interneurons (carry messages
between nerve cells)
The Structure of a Neuron
The Neural Impulse
Resting potential
Action potential
Synapse
Synaptic transmission
All or Nothing in the John – A demonstration
on neural transmission.
Seven Important Neurotransmitters –
DAN’S EGG
Dopamine
Acetylcholine
Norepinephrine
Serotonin
Endorphins
Glutamine
GABA
Neurotransmitters
Dopamine
Acetylcholine
Norepinephrine
Normal Function:
Produces sensations of
pleasure and reward; used
by CNS neurons in
voluntary movement
Problems with Imbalance:
Serotonin
Endorphins
Glutamine
GABA
Schizophrenia, Parkinson’s
disease
Substances that Affect:
Cocaine, amphetamines,
Ritalin, alcohol
Neurotransmitters
Dopamine
Acetylcholine
Norepinephrine
Serotonin
Normal Function:
Primary transmitter used by
neurons carrying messages
from CNS; involved in
some kinds of learning and
memory
Problems with Imbalance:
Endorphins
Certain muscular disorders,
Alzheimer’s disease
Glutamine
Substances that Affect:
GABA
Nicotine, botulism toxin,
curare, atropine
Neurotransmitters
Dopamine
Acetylcholine
Norepinephrine
Normal Function:
Controls heart rate, sleep,
sexual responsiveness,
stress, vigilance and
appetite
Problems with Imbalance:
Serotonin
Endorphins
Glutamine
GABA
High blood pressure,
depression
Substances that Affect:
Tricyclic antidepressants,
beta blockers
Neurotransmitters
Dopamine
Acetylcholine
Normal Function:
Regulates sleep and
dreaming, mood, pain,
aggression, appetite and
sexual behavior
Norepinephrine
Problems with Imbalance:
Serotonin
Endorphins
Depression, certain anxiety
disorders, obsessivecompulsive disorder
Glutamine
Substances that Affect:
GABA
Prozac, hallucinogenics
(e.g. LSD)
Neurotransmitters
Dopamine
Normal Function:
Acetylcholine
Pleasurable sensations and
control of pain
Norepinephrine
Problems with Imbalance:
Serotonin
Lowered levels resulting
from opiate addiction
Endorphins
Glutamine
GABA
Substances that Affect:
Opiates: opium, heroin,
morphine, methadone
Neurotransmitters
Dopamine
Normal Function:
Norepinephrine
Primary excitatory
neurotransmitter in CNS;
involved in learning and
memory
Serotonin
Problems with Imbalance:
Acetylcholine
Endorphins
Glutamine
GABA
Brain damage after stroke
Substances that Affect:
PCP (“angel dust”)
Neurotransmitters
Dopamine
Acetylcholine
Norepinephrine
Normal Function:
Most prevalent inhibitory
neurotransmitter in neurons
of CNS
Problems with Imbalance:
Serotonin
Anxiety, epilepsy
Endorphins
Substances that Affect:
Glutamine
GABA
Barbiturates, tranquilizers
(e.g. Valium, Librium),
alcohol
Agonists and Antagonists – Various drugs
affect communication at the synapse
•Agonists “excite”
•They mimic the effects of the
neurotransmitter.
•Opiate class drugs (e.g. vicodin,
heroin, morphine) are agonists.
•Can also enhance the
neurotransmitter.
•Nicotine turns up the volume of
ACH – it is why the person gets
“amped” up.
•Prozac and Zoloft are agonists –
they block the reuptake of the
seratonin to produce more
•Antagonists dampen or
inhibit the release of a
neurotransmitter.
•Botox is an antagonist –
doesn’t allow the release of
ACH – hence the muscle is
paralyzed.
•Curare then is also an
antagonist – paralyzes the
body by “turning off” ACH.
Plasticity
Plasticity –
Ability of the nervous system to adapt or
change as the result of experience;
sometimes helps the nervous system
adapt to physical damage
Glial Cells
Glial cells
• Provide structural support for neurons
• Help in forming new synapses
• Form myelin sheath
The Organization of the Nervous System
The Endocrine System
(the body’s chemical messenger system)
The Endocrine System
Pituitary gland –
Master gland that produces
hormones influencing the
secretions of all other endocrine
glands; produces hormone that
influences growth; attached to
hypothalamus
How Does the Brain
Produce Behavior and
Mental Processes?
The brain is composed of
many specialized modules
that work together to create
mind and behavior
Windows on the Brain
EEG (electroencephalograph) –
Device for recording brain waves,
typically by electrodes placed on the
scalp
Brain waves –
Patterns of electrical activity generated
by the brain
Windows on the Brain
Brain scans –
Recordings of the brain’s electrical or
biochemical activity at specific sites
• CT scanning (computerized tomography)
Windows on the Brain
Brain scans –
Recordings of the brain’s electrical or
biochemical activity at specific sites
• PET scanning (positron emission tomography)
Windows on the Brain
Brain scans –
Recordings of the brain’s electrical or
biochemical activity at specific sites
• MRI (magnetic resonance imaging)
• fMRI (functional magnetic resonance imaging)
Three Layers of the Brain
Brain stem and cerebellum
Drive vital functions, such as heart rate,
breathing, digestion
Limbic system
Adds emotions, complex motives, increased
memory abilities
Cerebrum
Enables reasoning, planning, creating,
problem solving
The Brain Stem and Cerebellum
Thalamus
Pons
Cerebellum
Medulla
Brain stem
Reticular Formation/Reticular
Activating System
The Limbic System
Hypothalamus –
Serves as the
brain’s bloodtesting
laboratory,
constantly
monitors blood to
determine the
condition of the
body
The Limbic System
Amygdala –
Involved in
memory and
emotion,
particularly fear
and aggression
The Limbic System
Hippocampus –
Involved in establishing
long-term memories
The Cerebrum
Cerebrum –
Topmost layer of the brain; the
bulbous cap over the limbic system
Cerebral cortex –
Thin gray-matter covering of the
cerebrum; carries on thinking and
perceiving
Cerebral hemispheres –
The two walnut shaped halves of the
cerebrum, connected by the corpus
callosum
The Four Lobes of the
Cerebral Cortex
Frontal lobes
(movement and thinking)
Parietal lobes
(touch sensation and spatial
relationships)
Occipital lobes
(contain visual cortex)
Temporal lobes
(process sounds, including
speech)
The Cooperative Brain
Association cortex –
Cortical regions that combine information
from various other parts of the brain
Cerebral Dominance
Cerebral dominance –
Tendency of each brain hemisphere to
exert control over different functions
Aphasia –
The loss of speech caused be brain
damage
Spatial orientation –
Process of locating one’s body or other
objects in space
Specialization of the
Cerebral Hemispheres
Left Hemisphere
Right Hemisphere
• Spontaneous
speaking and
writing
• Responses to
complex commands
• Word recognition
• Memory for words
and numbers
• Sequences of
movements
• Feelings of anxiety
• Positive emotion
• Repetitive but not
spontaneous
speaking
• Responses to simple
commands
• Facial recognition
• Memory for shapes
and music
• Spatial interpretation
• Emotional
responsiveness
• Negative emotion
The Split Brain
Split-brain patients –
Individuals who have had the corpus
callosum surgically severed
Duality of consciousness –
Condition in which a split-brain patient
has a separate consciousness in each
hemisphere
Split Brain Research: Roger Sperry and Michael
Gazzangia
Copyright © Allyn & Bacon 2007
End of Chapter 3