• Chapter 1
The Major Issues
• The Mind-Brain
Relationship
• Biological Psychology is the study
of the physiological and genetic
basis of behavior.
• Emphasis is placed upon
physiological, evolutionary and
developmental mechanisms of
behavior.
• A strong emphasis is placed upon
brain functioning.
• The Mind-Brain
Relationship
• Brain functioning can be explained
at a more microscopic level in
terms of neuron and glia activity.
• The Mind-Brain
Relationship
• Biological explanations of behavior
fall into four categories:
– Physiological- emphasis on brain
and other vital organs.
– Ontogenetic- describes the
development of a structure or
behavior.
– Evolutionary- focuses upon the
evolutionary history of a
behavior.
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– Functional- describes why a
structure or behavior evolved as
it did.
Mind – Brain
Physiological
Mind – Brain
Ontogenetic
Mind – Brain
Evolutionary
Mind – Brain
Functional
• The Mind-Brain
Relationship
• Deep understanding of a particular
behavior is tied to being able to explain
the behavior from each of these
perspectives.
• The Mind-Brain
Relationship
• Biological explanations of behavior raise
the issue of the relationship between the
mind and the brain also know as the
“mind-body” or “mind-brain problem”.
• The “mind-brain problem” has a variety
of explanations.
• The Mind-Brain
Relationship
• Dualism is the belief that there are
different kinds of substances and the
mind and the body are separate entities.
– Defended by French philosopher
Rene Descartes.
– Most common belief among
nonscientists.
– Rejected by most neuroscientists.
• The Mind-Brain
Relationship
• Monism is the belief that the
universe is only comprised of one
type of substance.
• Forms of monism include:
– Materialism- everything that
exists is physical by nature.
– Mentalism- only the mind truly
exists.
– Identity position- mental
processes are the same as brain
processes but simply described
in different ways.
• Mind – Brain
Monism
• Materialism – everything is physical
by nature
• Mind – Brain
Monism
• Mentalism – Only the mind truly
exists. George Berkeley said that
the mind is everything, nothing else
really exists.
• Mind – Brain
Identity position
• The Mind-Brain Relationship
• Explanations of the mind-body
relationship do not answer some
fundamental questions:
– Why is consciousness a
property of brain activity?
– What kind of brain activity
produces consciousness?
– How does brain activity produce
consciousness?
• The Mind-Brain Relationship
• Because “consciousness” is not
observable, it’s function is often
difficult to define and/ or explain.
• Solipsism- suggests that “I alone”
am conscious
– Difficulty of knowing if others
have conscious experiences is
known as the “problem of other
minds”.
• The Mind-Brain Relationship
• Chalmers (1995) proposes two
problems that must be
distinguished when discussing
consciousness:
– Easy problems - focus on
differences in conscious states
and their mechanisms.
– Hard problems - focus on why
and how brain activity is
associated with
consciousness.
• The Mind-Brain Relationship
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Research approaches to the
“hard problems” include:
– Using brain scan techniques to
identify specific regions of the
brain and the corresponding
amount of activity when a
stimulus is consciously
detected.
– Monitoring brain activity
when attention is directed
or focused upon varying
competing stimuli.
• The Mind-Brain Relationship
Careers
• Research
– Need Ph.D.
– Hold college or university position
– Or work at government or drug company lab
– May work at lab with only master’s
– Need to read Journals like Neurology,
Behavioral Neuroscience and Brain Research
• Fields of Specialization
• Specialization
Research Fields:
Neuroscientist
Behavioral neuroscientist
Cognitive neuroscientist
Neuropsychologist
Neurochemist
Comparative psychologist
Evolutionary psychologist
Practitioner fields:
Clinical psychologist
Counseling psychologist
School psychologist
Medical fields:
Neurologist
Neurosurgeon
Psychiatrist
Allied med fields
•
Description
Research positions ordinarily need a PhD, and are in universities,
hospitals, etc.
A broad term for someone studying the ana, biochem or physio of nervous
sys
Investigates how functioning of the brain and other organs influences
behavior.
Uses brain research, such as scans of brain anatomy or activity, to analyze
and explore people’s knowledge, thinking and problem solving.
Work in hosp and clinic – conducts beh tests to det ab and disab of brain
damaged
Investigates the chemical reactions in the brain
Compares behaviors of different species and relates them to their habitats
and ways of life
Relates behaviors, esp social, to the functions they have served and
therefore the presumed selective pressure
Not directly related to neuroscience, but need to understand it to comm
with doctors
Requires PhD or PsyD, in hosp, clinic, pvt practice or college – help with
emo prob
Requires PhD or PsyD. In hosp, clinic, pvt prac or college – helps make
edu, vocational and other decisions
Requires master’s or PhD in school system. Identifies edu needs of kids.
Need MD & 4 yrs of specialization, work in hosp, med sch, & pvt, & some
do research
Treat people with brain damage or diseases
Perform brain surgery
Help people with emotional distress or behavior probs, sometimes use
drugs and proc
Ordinarily need master’s – phy therapist, occup therapist and social
workers
• The Genetics of Behavior
• The Genetics of Behavior
• 19th century monk Gregor Mendel
demonstrated that inheritance occurs
through genes.
• Genes are basic units of heredity that
maintain their structural identity from one
generation to another.
• Genes are aligned along chromosomes
(strands of genes) and come in pairs.
• The Genetics of Behavior
• A gene is a portion of a
chromosome and is composed of
deoxyribonucleic acid (DNA).
• The Genetics of Behavior
• RNA is a single strand chemical
that can serve as a template/
model for the synthesis of proteins.
• Proteins determine the
development of the body by:
• forming part of the structure of
the body.
• serving as enzymes that serve
as biological catalysts and
regulate chemical reaction in the
body.
• The Genetics of Behavior
• Homozygous for a gene means
that a person has an identical pair
of genes on the two chromosomes.
• Heterozygous for a gene means
that a person has an unmatched
pair of genes on the two
chromosomes.
• The Genetics of Behavior
Homozygous and Heterozygous
• The Genetics of Behavior
Dominant-Recessive principle
• Genes are either dominant,
recessive or intermediate.
– Examples: eye color, ability to
taste PTC
• A dominant gene shows a strong
effect in either the homozygous
or heterozygous condition.
• A recessive gene shows its effect
only in the homozygous
condition.
• The Genetics of Behavior
Chromosomes
• Each chromosome participates in
reproduction independently of the
others.
• Each species has a certain number
of chromosomes.
• Crossing over occurs when a pair
of chromosomes break apart
during reproduction and reconnects
and attaches to the second
chromosome.
– BC & bc  Bc & bC
• The Genetics of Behavior
Crossing over
• The Genetics of Behavior
• Types of genes include:
– Autosomal genes - all genes
except for sex- linked genes.
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– Sex-linked genes - genes
located on the sex
chromosomes.
In mammals, the sex
chromosomes are designated X &
Y.
– Females have two X
chromosomes (XX).
– Males have an X and a Y
chromosome (XY).
The Genetics of Behavior
Karyotype of a male human
The Genetics of Behavior
Sex linked traits
The Genetics of Behavior
During reproduction:
– Females contribute an X
chromosome.
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– Males contribute either an X or a
Y chromosome that determines
the sex of the child.
If an X chromosome is contributed
by the male, the off-spring is
female.
If a Y chromosome is contributed
by the male, the off-spring will be
male.
The Genetics of Behavior
The human Y chromosome has
genes for 27 proteins
The human X chromosome has
genes for approximately 1500
proteins.
Thus, sex-linked genes usually
refer to X-linked genes. (Example:
Red-green color deficiency)
Sex-limited genes are genes that
are present in both sexes but
mainly have an effect on one sex
(Chest hair, breast size, etc.)
• The Genetics of Behavior
• Sex linked are those that are
located on X and Y chromosomes
• Sex limited are those traits that are
affected by being male or female
• The Genetics of Behavior
• Sources of variation in a species
that allows for evolution to occur
include:
• Recombination refers to a new
combination of genes in the offspring that yield characteristics not
found in either parent.
• Mutation refers to a change in a
single gene that is rare, random
and often independent of the needs
of the organism.
• The Genetics of Behavior
Recombination
• The Genetics of Behavior
Mutation
• The Genetics of Behavior
• Almost all behaviors have both a
genetic component and an
environmental component.
• Researchers study monozygotic
and fraternal twins to infer how
much of a genetic component
exists for a particular behavior.
• Researchers also study adopted
children and their resemblance to
their biological parents to infer the
influence of heredity.
• The Genetics of Behavior
• The Genetics of Behavior
• Estimates of hereditary influences
are often difficult to infer and are
prone to error.
• Sources of error include the
following:
– The inability to distinguish
between the effects of genes
and prenatal influences.
– Environmental factors can
inactivate genes.
• The Genetics of Behavior
• Sources of error (con’t)
– Multiplier effect – genetic
tendencies that guide behavior
will result in a change in the
environment that magnifies the
original tendency.
– Traits with a strong hereditary
influence can by modified by
environmental intervention.
• Eg. “elevated plus maze”,
PKU
• The Genetics of Behavior
Genes  Behavior
• Genes do not directly produce
behaviors.
• Genes produce proteins that
increase the probability that a
behavior will develop under certain
circumstances.
• Genes can also have an indirect
affect.
– Genes can alter your
environment by producing
behaviors or traits that alter how
people in your environment react
to you.
• The Genetics of Behavior
Scarr - Influence of Genes on the
Environment
• Passive – Parents who give you
your genes also shape your
environment
• Evocative – as you grow adults
around you realize your potential –
your genes evoke an appropriate
response from the environment
that fosters them
• Active – as you grow into
adulthood you actively seek out
environments that foster your
particular talents etc.
• The Genetics of Behavior
• Evolution refers to a change in the
frequency of various genes in a
population over generations
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Evolution attempts to answer two
questions:
• How did some species evolve?
• How do species evolve?
The Genetics of Behavior
How species did evolve involves
the tentative construction of
“evolutionary trees”.
The Genetics of Behavior
How species do evolve rests upon
some assumptions:
• Offspring generally resemble
their parents for genetic
reasons.
• Mutations and recombination
of genes introduce new
heritable variations that help or
harm the chance of survival
and reproduction.
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Certain individuals successfully
reproduce more than others
do.
• The Genetic of Behavior
• Common misconceptions about
evolution include the following:
– Lamarckian evolution - “The use
or disuse of some structure or
behavior causes an increase or
decrease in that behavior.”
– “Humans have stopped
evolving.”
– “Evolution means improvement.”
– “Evolution acts to benefit the
individual or the species.”
• The Genetics of Behavior
• Evolutionary psychology
(sociobiology) focuses upon
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functional explanations of how
behaviors evolved.
Assumes that behaviors
characteristic of a species have
arisen through natural selection
and provide a survival advantage.
– Examples: differences in
peripheral/color vision, sleep
mechanisms in the brain, eating
habits, temperature regulation.
The Genetics of Behavior
Some behaviors are more
debatable regarding the influence
of natural selection.
Examples include:
– Life span length
– Gender differences in sexual
promiscuity
– Altruistic behavior – a behavior
that benefits someone other than
the actor
• Explanations: reciprocal
altruism & kin selection
• The Use of Animals in Research
• Animal research is an important
source of information for biological
psychology but remains a highly
controversial topic.
• Animal research varies on the
amount of stress and/ or pain that
is caused to the animal itself.
• The Use of Animals in Research
Reasons for studying animals
include:
• The underlying mechanisms of
behavior are similar across
species and often easier to
study in nonhuman species
because
• Animals have simpler
structures
• Animals have shorter
lifespans
• We are interested in animals
for their own sake.
• What we learn about animals
sheds light on human
evolution.
• Some experiments cannot use
humans because of legal or
ethical reasons.
• The Use of Animals in Research
• Opposition to animal research
varies:
– “Minimalists” favor firm
regulation on research and place
consideration upon the type of
animal used and the amount of
stress induced.
– “Abolitionists” maintain that all
animals have the same rights as
humans and any use of animals
is unethical.
• The Use of Animals in Research
• Justification for research considers
the amount of benefit gained
compared to the amount of distress
caused to the animal.
– No clear dividing line exists.
• Colleges and research institutions
in the United States are required to
have an Institutional Animal Care
and Use Committee.
– Oversees and determine
acceptable procedures.