Download Physiological Basis of Behavior

Sept 30th 2012
Emotions and behavior are a
product of anatomy &
physiology
 Behavior
& mental activity can be traced
back to physiological events
 Research
proves that there are biological
correlates of behavior
 Link
between psychology & physiology
Biopsychology
 Is
the study of biological bases or
physiological correlates of behavior
 Branch
 Studies
of neuroscience
the nervous system and how it
impacts behavior
3 areas of correlation
 Neurotransmitters
Effect of the nervous system.
 Hormones
Effect of the endocrine system
 Brain
Localization
The Brain.
 http://www.youtube.com/watch?v=PE2b
5go7V_0&feature=related
Neurons
Communication between
neurons
What is a neurotransmitter ?
A neurotransmitter is a chemical messenger that carries and modulates signals
between neurons and other cells in the body.
Fact: Scientists do not yet know exactly how many neurotransmitters exist, but more
than 100 chemical messengers have been identified.
We have 10 and 100 billion neurons in the nervous system. The neurons send
electrochemical messages to the brain so that we can respond to stimuli – either
from the environment or from internal changes in the body. The method by which
these messages are sent is called neurotransmission.
They can affect behavior as varied as mood, aggression, appetite, memory and
mental illness.
Understanding
Neurotransmitters
 http://www.youtube.com/watch?v=NjgB
nx1jVIU&feature=related
Neurotransmission effects:
 Arousal,
alertness: Norepinephrine
 Moods and emotions: Serotonin
 Memory : Acetylcholine
 Sexual arousal: Oxytocin
 Mental illness: Dopamine
 Feelings of pleasure/ Learning: Dopamine
Research Studies (Crane &
Hannibal)
 Serotonin
study
Kasamatsu & Hirai, 1999
 Neurotransmitters
in Learning & Memory
Martinez & Kesner, 1991
 Examples-
schizophrenia
Parkinsons dopamine
What is acetylcholine?
http://www.youtube.com/watch?v=AyoySswpvso
Homework Read
Article
for Tuesday 2nd.
Oct 2nd 2012
Neurotransmission effects:
 Arousal,
alertness: Norepinephrine
 Moods and emotions: Serotonin
 Memory : Acetylcholine
 Sexual arousal: Oxytocin
 Mental illness: Dopamine
 Feelings of pleasure/ Learning: Dopamine
What is acetylcholine?
http://www.youtube.com/watch?v=AyoySswpvso
Write a summary. 200 words. Use psychological words.
Due: Thursday 4th
DRUGS
Drugs? Do
they affect
me?
YES
No Doubt
Drugs & Neurotransmission
Drugs can impact:
1. Release of neurotransmitter into the synaptic gap:
by preventing/ encouraging production thus
increasing/decreasing synapse.

2. Binding of neurotransmitter to receptor site: by
occupying receptor site
- Effects receiving neuron + prevents
communication
3. Reuptake- allowing more time to bind with
receiving neurons
Mouse Party
 http://learn.genetics.utah.edu/content/a
ddiction/drugs/mouse.html
More examples
 http://www.thirteen.org/closetohome/sci
ence/html/animations.html
Long term use of drugs causes structural
change in the brain as it adapts to the
altered activity to neurotransmitters . The
most important effect of this adaptation is
increased tolerance for the drug. This
means that a person needs more of the
drug to feel the same effect.
NEUROTRANSMITTER SUBSTANCES
 Acetylcholine
 Norepinephrine
 Gamma-aminobutyric
 Dopamine
 Serotonin
 Endorphin
acid
Different Neurotransmitter Substances
and their Effects on Behavior
Neurotransmitter
1. Acetylcholine
Effects on Behavior
Facilitates learning and
memory
Deficiency of ACH
disrupts learning and
memory
2. Norepinephrine
Too
little may lead to
depression
Too much causes
hyperactivity
Neurotransmitter
Effects on Behavior
3. Dopamine
Over
4. Serotonin
Lack
supply may lead to
schizophrenic reaction
Under supply causes
Parkinson’s Diseases (a
neurological disorder disrupting
coordinated movement)
of serotonin produces
anemia
Prevents dreaming in the waking
state
Considered as the “worry”
chemical in the brain
Neurotransmitter
Effects on Behavior
5. GABA (gamma
acid aminobutyric
acid)
Decreases
6. Endorphins
the activity of
the neuron
May decrease levels of
anxiety
 Pain relieving effect; a
neuropeptide
Class Work
Read Serotonin article.
Brief debate
Is there any way we
can regulate serotonin
and endorphins?
Increase?
Oct 3rd 2012
Neurotransmitter
Effects on Behavior
3. Dopamine
Over
4. Serotonin
Lack
supply may lead to
schizophrenic reaction
Under supply causes
Parkinson’s Diseases (a
neurological disorder disrupting
coordinated movement)
of serotonin produces
anemia
Prevents dreaming in the waking
state
Considered as the “worry”
chemical in the brain
Mental illness
related to
Neurotransmitter?
Dopamine
Neurotransmitter imbalances and mental illness
Neurotransmitter imbalance is one theory about the
cause of mental illnesses.
The basic idea is that neurotransmitter imbalances
within the brain are the main causes of mental
illnesses and that these conditions can be improved
with medication which corrects these imbalances.
Research into other mental illnesses such as
schizophrenia also found that too little activity of
certain neurotransmitters was correlated to this
disorder.
Schizophrenia is an extremely complex
mental disorder
The first signs of schizophrenia tend to surface
in adolescence or young adulthood.
People with schizophrenia suffer from
problems with their thought processes. These
lead to hallucinations, delusions, disordered
thinking, and unusual speech or behavior.
Symptoms affect the ability to interact with
others, and often people with schizophrenia
withdraw from the outside world.
Famous people with schizophrenia:
http://www.youtube.com/watc
h?v=ZHpKvmTJOhA
Dopamine hypothesis:
• Schizophrenia is associated with increased activity at dopamine
receptor sites.
Antipsychotic (treatment) drugs exert their clinical effect by reducing
increased dopamine activity.
The hypothesis is based on experimental and accidental drug
combinations and types that either increase dopamine activity and therefore
schizophrenic symptoms or decrease dopamine activity and therefore reduce
symptoms.
So for example it is supported by the fact that amphetamines and cocaine,
which trigger the release of dopamine have been found to exacerbate the
psychotic symptoms in schizophrenia.
This is called dual diagnosis: example of the shelter
http://www.youtube.com/watch?v=xwRdNz8HA0Q
Class work
Read pages 40,41,42
Brief summary.
Oct 9th 2012
The use of
technology
in brain
research
Modern Technology
What you need to know
-
Explain the technology
Uses
Strengths vs Limitations
Examples of research using this
technology
EEG:
Electroencephalogram
 Hans
Berger, 1929
 Electrodes placed outside the person’s
head in specific locations
 Using a cap/helmet with electrodes on
standardized places on the skull
 Detect changes in electrical activity
 EEG- produces the graphical
representation of the activity from each
electrode
Strengths vs Weakness
 Strength:
Used for sleep studies
- Brain activity changes in specific ways
during sleep
 Not sufficiently accurate because
electrodes are outside the skull
 Detect uncountable neurons hence give
vague picture
 Not sufficient to understand localization of
brain
CT: Computed
tomography
 Earlier
called CAT
 Combines computer & x-ray technology
 Xray shows human bones very well
 Computer lets us see the brain
 Images look like slices of the brain
 Eg: The case of Janet
Strength- Weakness
Strength:
 Can see the brain from several angles &
depth
 Extremely useful to see structure of the brain
- Can show changes caused by brain damage
Weaknesses
 Can show only structure not brain activity
 Danger of exposure to x-ray radiation
MRI (Magnetic Resonance
Imaging)





When body exposed to strong magnetic field,
protons in the water in the body change
alignment
Magnetic field + radio frequency fields usedhydrogen atoms alignment change to be
detectable by a scanner
This signal transformed into visual
representation
Image represents slice of the brain taken from
any angle
Can be used to create 3D image of the brain
Advantages
 More
precise
 No danger of x-ray radiation
fMRI- Functional MRI





When neurons in particular region are activeblood in the region increases
It maps metabolic changes that indicate
brain activity
Provides precise picture of parts of the brain
active during a cognitive/affective process
Correlated human activity with brain activity
More precise than PET
PET: Positron emission
tomography
 Inject
radioactive substance into patient
 Produces gamma rays as it is metabolized
by brain
 Scans monitors glucose metabolism in the
brain.
 Parts of the brain metabolize at different
rates depending on level of activity
 Gamma rays detected by machine
 Signal turned into computer image
 Shows colorful map of activity in the brain
Strengths vs Weaknesses
 Shows
dynamic activity of brain but not
precise like fMRI
 Good as an early diagnostic tool
Eg: Alzheimer's progression of disease only
then structural changes
 Shows abnormality in activity levels
 Like Ct Scans needs to be used with
discretion depending on patients health
Class Work. Write ventajas
e inconvenientes de cada
uno
TOK: Ethics
Work in groups of 3
The use of PET and MRI scans has helped psychologist to identify
brain patterns for dysfunctional behaviors. Therefore, there is
certain pattern for people with schizophrenia, alcoholism, and
depression , among other disorders.
1.
Do you think that doctors should scan patients to let them
know if they have a predisposition for a mental illness? What
effect do you think this would have on individual?
2.
Could this technology be misused? Does the potential abuse
of technology and knowledge mean that it should not be
pursued?
Write a brief summary. Be a critical thinker
Due: Tuesday 16th
Teens Brain
 http://www.pbs.org/wgbh/pages/frontlin
e/shows/teenbrain/view/
Debate a teen’s brain
Prepare for Test
 Sunday
14th
Oct 10th 2012
Read Page 46
What is
neuroplasticity?
Refers to the concept the
specific location of a function is
NOT necessarily fixed for all
individuals. The more a person
performs particular activity, the
more neuronal connections are
formed in the area of the brain
responsible.
Plasticity refers to the process of making
long-term changes in the brain. Often
these changes occur as a result of learning.
During development (the period of intense
growth and change from conception
through early childhood), neurons can
change shape, location, function, and
patterns interconnection”
Dendritic branching: every time
we learn something new, the
neurons connect to create a new
trace in the brain.
Study. Maguire 2000.
Changes in the brains of
experienced London taxi drivers.
It is known that animals which employ spatial memory
seem to show morphological
changes in the
hippocampus. Maguire predicted that fully licensed
London taxi driver will have structural differences in their
hippocampus as a result of this learning experience.
They found that left and right hippocampi were
significantly higher in volume in taxi’s driver brain. This is
likely to be a strengthening of connections between
neurons in well- used part of the brain
http://www.youtube.com/watch?v=Fgd-uyNBA08
Read Bilingual Article.
Class work: Write first
and then talk in pairs.
Be a critical thinker!
1.Highlight the studies.
2.Findings.
3.Work in pairs and
explain.
Environment
function
and
brain
Taxi driver study and Bilingualism article.
Conclusion:
“It shows how important the environment is
in shaping the structure of the brain and the
brain
helps
account
for
individual
differences in brain structure and function”.
Study Rosenzweig and Benett
(1972) conducted an experiment to measure the effect
of either enrichment or deprivation on the development of
neurons in the cerebral cortex
Conclusion: The cerebral cortex (responds to experience
and is responsible for movement, memory, learning, and all
sensory input) of the enriched rats was significantly heavier
and thicker.
Cortical thickness increases even further if the rats are
placed with other rats. The combination of having company
and many interesting toys created the best conditions for
developing cerebral thickness.
Remember Meditation
experiment?
 Using
a PET scan, Davidson observed an
increase in the number of gamma waves
in their brain during meditation.
 As
soon as they stopped meditating, the
volunteers gamma wave production
went to normal.
 This
led to think that meditation could
have a significant long term effects in the
brain and the way it process emotions.
Oct 16th 2012
The effect of cognition on
physiology
Mirror Neurons
Another way in which brains interact with
environment hast to do with how people
learn. A mirror neuron is a neuron that fires
when and animal observes somebody else
perform the same action.
Examples
 http://www.youtube.com/watch?v=t0pw
KzTRG5E
Effects of social behaviors on mirror neurons
Another way in which the brain and
environment interact is through the
activity of the recently discovered mirror
neurons.
Mirror neurons are neurons that fire when
an animal performs an action or when
the animal observes somebody else
perform the same action.
Study 1 Rizzolatti, Gallese, and Fogassi ( 1996 ), at the University of
Parma, Italy discovered them by chance . The discovery came
when one of the researcher walked into the room where the
monkey was and reached out and picked up a peanut. As the
monkey watched, its premotor neurons fired just as they had when
the monkey had picked up the peanut.
Some scientists such as Ramachandran
consider mirror neurons one of the most
important
recent
discoveries
in
neuroscience, possibly giving insight into
the neurobiological foundations of a
number of behaviors including empathy,
and lack of empathy in disorders such as
autism.
Despite the excitement
generated by these findings,
research is still in its infancy. To
date no widely accepted neural
or computational models have
been put forward to describe
how mirror neuron activity
supports cognitive functions such
as imitation.
Personal examples of
Mirror Neurons
Functions of hormones in in
human behavior
Hormones
 1.
Adrenaline
 2. Cortisol
 3. Melatonin
 4. Oxytocin
 5. Testosterone / estrogen
Hormones
 1.
Adrenaline: flight or fight response
 2. Cortisol: Arousal, stress hormone,
memory
 3. Melatonin: Regulation of sleep
 4. Oxytocin: Mother and child
attachment
 5. Testosterone / estrogen: development
and emotions
Oxytocin:
"love
hormone”.
It plays a role in inducing contraction and
lactations, and is released with touches and
hugs. It is associated with bonding between
and a mother and her child.
Recent studies has been found to be
beneficial for reducing anxiety and stress,
producing feelings of well-being, empathy,
bonding, and sexual arousal.
Oxytocin and sex
Oxytocin is released by both men and women at sexual
orgasm.
Massage
For example by touch and warmth. Bloodstream levels of
oxytocin have been shown to rise during massage.
Smiles
Oxytocin may increase one's ability to remember happy smiling
faces but I have not seen studies yet that smiling itself increases
one's oxytocin levels.
Availability of oxytocin drug
Oxytocin is sold as nasal spray (Syntocinon). A nasal spray
containing the hormone oxytocin, which is essential to the
production and flow of breast milk, does not improve milk output
in mothers expressing milk for preterm infants.
Intranasal administration of oxytocin causes a substantial
increase in trusting behavior.
Oxytocin and bonding
The levels of oxytocin hormone in a pregnant woman's body
play a role in how closely she will bond with her newborn.
Studies
DItzen ( 2009 )
Where: Zurich
What: Adult couples were randomly assigned into two groups: one group of
participants were administered oxytocin intra-nasally and the other group received
placebo, also in a nasal spray. They were asked them to discuss a subject they
often disagreed
Outcome: Reduced levels of the stress hormone cortisol and increased positive
communication behavior, compared to the placebo.
Study: Oxytocin may also play a role in autism and may be an effective treatment
for autism’s repetitive behaviors. Two related studies in adults, in 2003 and 2007,
found that oxytocin decreased repetitive behaviors and improved interpretation of
emotions ( Jacob et al, 2007 ). More recently, intranasal administration of oxytocin
was found to increase emotion recognition in children as young as 12 who are
diagnosed with autism spectrum disorders (Wermter, 2009).
Video about love
http://www.ted.com/talks/lang/e
n/helen_fisher_studies_the_brain_i
n_love.html
Oct 17th 2012
Experiment
Pay attention to your own
body.
http://www.youtube.com/wat
ch?v=pMB_VpvhBKw
Adrenaline: (also known as epinephrine)
is a hormone secreted by the adrenal
gland. Adrenaline helps the body to
adjust to sudden stress.
Situation: When a person becomes
angry or frightened, the adrenal gland
releases adrenaline into the blood
Symptoms: Adrenaline increases
a. the strength and rate of the
heartbeat and raises the blood
pressure.
b. It also speeds up the conversion of
glycogen into glucose, which provide
energy to the muscles.
c. these physiological changes are
responsible for the ‘fight or flight’
response.
Class work . Read
page 54- 55. Discuss
empirical research
Oct 18th 2012
What is adrenaline?
Study Case Study
The role of adrenaline in the emotion of anger was
demonstrated in the classic study by Schacter & Singer (1962).
They gave 3 groups of participants an adrenaline injection
(epinephrine) and 1 group a placebo, and then put them into
situations designed to create an emotional response of anger
or happiness.
Schacter & Singer concluded that a stimulus triggers a
physiological response ( adrenaline release) and at the same
time the stimulus is interpreted in the brain taking into account
previous experiences of similar situations. So, emotion is an
interaction of both cognitive and hormonal factors
Homework Exercise:
• Make a table summarizing the effect on
behavior of the three hormones
examined using the column title:
Hormone name, behavior affected and
example.
Due: Sunday 21st .
Oct 21th 2012
Hormones
 1.
Adrenaline
 2. Cortisol
 3. Melatonin
 4. Oxytocin
 5. Testosterone / estrogen
What is melatonin?
 Hormone
that is naturally produced by
the pineal gland.
 Conveys information to various parts of
the body
 Chemical structure identified in 1958
 Expressed rhythmically throughout the
day

How Melatonin Works
 Melatonin
levels cycle
 Low levels during daylight, rise during
nighttime
 Peak levels between 11PM and 3AM
 Levels continue to cycle in constant
darkness
 Can slowly adjust to environmental
changes
Seasonal effective disorder

Seasonal affective disorder (SAD), also known as winter
depression, winter blues, summer depression, summer
blues, or seasonal depression, is a mood disorder in
which
people
who
have
normal
mental
health throughout most of the year experience
depressive symptoms in the winter or summer, spring or
autumn year after year. In the Diagnostic and Statistical
Manual of Mental Disorders (DSM-IV), SAD is not a
unique mood disorder, but is "a specifier of major
depression
Seasonal effective disorder
 Seems
to be more common on northern
climates with long, dark winters. However,
the worst time of year for many ( with an
increased number of suicides) seems to
be the spring.
 http://www.youtube.com/watch?v=2bo_l
qFG_20
Debate
 Egypt
VS Sweden
 What would you think in terms of mood?
Does it affect you?
 Fact:
Oct 23th 2012
Genetics and Behavior
Thomas Bouchard’s concordance
study of identical twins (1979)






Twins were separated at birth and reunited at
age of 39
Both drove Chevrolets and enjoyed stock car
racing
Both had a background in police work and
had worked part-time as deputy sherifs
Both chain-smoked and took holidays in
Florida
Both had a workshop in the basement of their
house where they built furniture
Both had been married twice. The first wives
were called Linda
 Both
had sons that were called James
Alan
 Both had dogs named Toy
 Both had similar medical histories
(identical blood and pulse pressure and
haemorrhoids)
 Both had put on 10 pounds at the same
time earlier in their lives
Chromosomes
 Threadlike
structures
in the cell
 Composed of double
strands of DNA and
proteins, containing
the genes.
 In
humans, there are
23 pairs of
chromosomes
 You inherit one half of
each pair from each
parent
DNA



The molecule that
encodes genetic
information.
DNA is a double-stranded
molecule held together
by weak bonds between
base pairs of nucleotides.
The four nucleotides in
DNA contain the bases:
adenine (A), guanine (G),
cytosine (C), and thymine
(T).
Duplicates itself during
meiosis (division of cells)
Genes





The basic unit of heredity
Made up of sequences of
“building blocks” called
amino acids.
Humans possess about
30,000 genes, each
regulating production of
various proteins.
Genes functions in pairs
Variants of genes are called
alleles
Which genes are
expressed?
 Consider
eye colour:
B = brown eyes (dominant)
b = blue eyes (recessive)
 So
what colour eyes would a person
have with the following gene pairs?
 BB
 Bb
 bb
Genotype, Phenotype, Mutation



Genotype: The genetic
code which an individual
carries in the DNA of their
cells
Phenotype: The observed
characteristics of the
individual, based on the
combination of genotype
and environmental
influences
Mutation: A change in the
genetic material of a cell.
While rare, mutations can
result in new characteristics
which may be transmitted
to descendants of the
original cell.
Dominant vs Recessive
Brown eyes
Blue eyes
Dark hair
Blond/red hair
Curly hair
Straight hair
Colour vision
Colour blindness
Normal sight
Night blindness
Normal blood
Haemophilia
Hearing
Congenital Deafness
Types of correlation studies
in behavioral genetics
research
 Concordance
studies (twin studies):
Measure the degree of similarity in
characteristics, such as intelligence,
between genetically related and
unrelated individuals
 Molecular genetics studies: Compare
genetic material from individuals with a
certain characteristic with individuals
without the certain characteristic.
Study Lykken & Tellegen
(1996)
 Aim:
To investigate how closely twins’
moods correlate
 Participants: 3,000 identical & fraternal
twins
 Results: Identical twins, unlike fraternal
twins, have similar moods regardless of
whether they have been raised together
or separated at birth.
Concordance or molecular
study?
Bouchard (1990)
 Aim:
To investigate relationship between
heredity and weight gain
 Participants: 12 pairs of male identical
twins
 Procedure: Participants stayed in a
dormitory for 100 days to gain weight (ate
4 large meals per day)
 Results: Twins gained the same amount of
weight in same places in the body.
Concordance or molecular
study?
Oct 24th 2012
How does this example
illustrate the concepts of
phenotype and genotype?

John and Alan are identical twins who were
separated at birth. Alan was raised in a
very impoverished environment. John is
substantially taller than Alan.
Caspi 2003
 Aim:
To investigate the relationship
between the 5-HTT gene (The serotonine
transporter gene) and depression
 Participants: 847 Caucasian New
Zealanders
 Controls: Checked that participants were
honest in self report by cross checking
with friend, same levels of stressful life
events
 Findings: Having a short allele of the 5-HTT
gene correlated with increased
vulnerability for depression between ages
of 21 to 26
Concordance rate
 The
probability that a pair of individuals,
e.g. a twin pair, will both have a certain
characteristic, given that one of the pair
has the characteristic.
 Concordance
heritability!!!
does not mean
Heritability
The extent to which the variability found in a
characteristic or trait is hereditary is known as
the heritability coefficient (score from 0 to 1)
O
100 % down to
environment
1
100 % down
to genes
For example, eye colour is solely determined by genes so has a heritability
coefficient of 1. Height is slightly influenced by environment and has a heritability
coefficient of 0.9
Guess the heritability
coefficient for the following
behaviors











Depression
Phobias
Memory
Personality
Intelligence
Happiness
Homosexuality
Schizophrenia
Religious values, political beliefs and vocational
interests
Aggression
Alcoholism
Heritability coefficents for
some behaviors











Depression: .3
Phobias: .3 to .5
Memory: 0 to .8
Personality: .2 to .45
Intelligence: .5 to .8
Happiness: .6 to .8
Homosexuality: .4 to 1
Schizophrenia: .5 to .85
Religious values, political beliefs and vocational
interests: .14 to .5
Aggression: .40
Alcoholism: .65
How genes influence
behavior
Genes
influence behavior
indirectly. Genes influence the
production of proteins that
affect the anatomy (e.g. brain
structure) and physiology
(chemical processes) of the
body
There is usually more than one
gene involved in a behavior
Some
behaviors are more
genetically influenced than
others
There is an interaction between
environmental, biological,
cognitive and genetic factors
in the development of
behavior (e.g. diathesis-stress
model)
Classwork. Explain
 Think
about your genes and your family.
What behavior can be genetic from your
parents?
 What type of your behavior can be
influenced by enviromment?
Evaluation, criticism
 Problems
with research: Problems of self
report, researcher expectancies, samples
might not be representative,
generalisability problems, correlational
studies cannot infer cause-effect of
behaviour, validity problems, other factors
may affect concordance rates.
 Some behaviors have stronger heritability
than others
 Ethical issues if there are racial or
individual differences due to genes
With reference to relevant research studies, to what
extent does genetic inheritance influence behaviour?
http://neuro.bcm.edu/eagleman/neurolaw/papers/%5BCa
spiEtAl2003%5DInfluenceStressOnDepression5HTTGen
e.pdf
http://www.personalityresearch.org/papers/jones.html
http://www.bio.davidson.edu/courses/genomics/2003/choi
/1.html
Research on intelligence
Behavior may be influenced by evolutionary
processes
Evolutionary processes is based on Darwin’s theory of natural
selection – natural selection is the process by which species adapt to
their environment.
For example adaptations which would have promoted survival and reproduction such as
aggression might be understood as an adaptive necessity in the competition for limited
resources. This is widely demonstrated in research.
Study 1: Chartrand & Bargh (1999) The chameleon effect is the natural tendency to
imitate each other’s each other’s body postures, hand gestures, speaking accents, and
other behaviors. people who engaged in more imitative behavior rated the person they
imitated higher in terms of likeability, suggesting that mimicry (imitation) facilitated social
interaction and bonding. Example of Accent and Australia. New in the school
Examine one evolutionary explanation of behaviour.
http://www.guardian.co.uk/technology/2010/mar/14/my-bright-idearobin-dunbar
Activity
Calculate concordance rates between you
and a randomly chosen classmate on:
 Tv series you like to watch
 Food that you like to eat
 Friends that you have in common
 Any other similarities
1.6 Evolutionary
Psychology
Examine one evolutionary explanation of behavior:
What? Evolutionary psychology is a combination of evolutionary biology and cognitive
psychology. It sees the mind as a set of evolved mechanisms, or adaptations, that
have promoted survival and reproduction. All behavior is a result of these evolved
mechanisms.
To understand evolutionary psychology it is necessary to have a basic understanding
of genes, inheritance, and the principles of natural selection.
Darwin and Natural selection
Evolutionary psychology is inspired by the work of Charles Darwin and applies his
ideas of natural selection to the mind.
Darwin ( 1859 ) observed the relationship of plants and animals all over the world,
including organisms (finches ) on islands off the coast of South America and those on
the mainland. These observations showed that they were related but not identical.
This led Darwin into believing that over time things must adapt to suit their
environment Darwin's theory argues that all living species, including humans, arrived
at their current biological form through a historical process involving random
inheritable changes ( genetic mutations)
What extent does genetic inheritance influence behavior?
Anti-social behavior/aggression
Aggression seems to have a strong genetic component.
Study 1. Grove et al ( 1990) studied 32 sets of twins who were separated and raised apart shortly after birth.
A continuous score for anti-social behavior in both childhood and adulthood was derived by interviewing each
subject with a standardised interview schedule; as such this assessment of antisocial behavior was a selfreport measure.
Statistically significant heritabilities were obtained for anti-social behavior in both childhood (0.41) and
adulthood (0.28).
What about their environment? Is the environment affecting their behavior? What about culture?
Different countries like Africa and Spain?
Environmental Influences
Fact: Thus far it has been established through research and various studies that
genetics do influence criminal or antisocial behavior.
However, researchers also agree that there is an environmental component that
needs to be examined.
Social Learning theory (1965)
Albert Bandura argued that individuals, especially children, are not born with
aggressive tendencies but learn aggressive behaviors from observing others,
either personally or through the media and environment.
In a lab experiment, children observed an adult model beating an inflatable doll.
Children who watched the aggressive models showed both physical and verbal
aggression when later put in a room by themselves with the toy.
In fact 88% of the children imitated the aggressive behavior. Bandura also argued
that aggressive behavior is strengthened and maintained if it has a desirable
outcome (reinforcement).
Demonstrates the influence of the environment, although there are challenging
studies such at the St.Helena TV study. Children, in the remote Pacific Island of St.
Helena, who were newly exposed to TV did not demonstrate increased levels of
violence.
This suggests other factors must account for aggression, than mere observation.
Conclusion: Gene-environment interactions
Psychologists now believe that an individual may have
a genetic predisposition towards a certain behavior,
but without the appropriate environmental stimuli this
behavior may not be manifested (eg a genetic
predisposition towards depression, but a happy
childhood environment).
Some changes are adaptive, that is, they increase an individual's
chances of surviving and reproducing.
Changes of this kind are more likely to be passed on to the next
generation (natural selection), while changes that hinder survival
are lost.
Examples of adaptations which would have promoted survival
and reproduction are behaviors such as aggression which might
be understood as an adaptive necessity in the competition for
limited resources.
“Chameleon effect”
Chartrand & Bargh (1999) who investigated the human tendency to mimic the behavior of another in
a social situation. They called this the ‘chameleon effect’ and argued that the unconscious habit of
imitating behaviors such as foot-tapping enables rapport-building and social bonding between
individuals. Social bonding would have been essential for survival of the group in terms of securing
and sharing food and shelter.
Example of accent into new countries. Moving to America.
Chartrand & Bargh found that participants who were most likely to mimic behaviors of a confederate
were more likely to rate them higher in terms of likeability in a later part of the experiment. This
supports their hypothesis that unintentional mimicry and imitation facilitates social bonding.
Example of new in the school.
Example of not adapting /imitating. Side effects.
1.7 Ethical Considerations
into genetic influences on
behavior
Discuss ethical considerations in research into genetic
influences on behavior
Ethical consideration
Explanation
Confidentiality, privacy
Given the familial nature of genetic research, confidentiality, privacy and
and security
security are important considerations in ethical review of a genetic study. Genetics research can sometimes, either directly or by implication, reveal private
information to one individual about other members of their family. It might reveal information about health status, or even about mis-attributed parentage, either
through discussion of the result of a genetic test or in the process of collecting information for the construction of a family pedigree. A research subject may read or
deduce information provided by other family members. Such information may be disclosed by accident through
questions asked by a researcher about the family history. Accidental disclosure of such information can have consequences for the broader family and for one
person’s relationships with other family members. It may be revealed later by one family member to another during a family conflict, or may itself become the subject
of a dispute.
Development of a perception that a person is ‘ill’
• Low self-esteem on the part of the person tested
Potential psychological harm from genetic testing • Serious psychological maladjustment, even perhaps depression and suicide
• Parental guilt
• Social discrimination, including future employment and insurance
discrimination
• May remove child’s autonomy to make decisions as an adult
• Changes in family perceptions and expectations for child
• Identification of other family members at risk who wish not to know
Accuracy of results
Ethical concerns may arise over the accuracy of tests. Preliminary findings may later turn out to be false.
Debate 1
Who has the right to know if an unborn child has a genetic predisposition to a
disorder that may develop in adulthood?
Does it matter if there is no treatment yet available for the disorder?
Debate 2
Should government invest to help increase IQ if it is genetic?
Practice Questions
Short answer questions
Identify 2 hormones and using examples, explain their function in
human behavior.
Describe one evolutionary psychology explanation of behavior
Explain one interaction between cognition and physiology
Explain one study related to localization of function in the brain
Essay Questions
1.Discuss the use of the brain imaging
technologies in investing the relationship
between biological factor and behavior.
2. Discuss ethical consideration related to
research studies at the biological level of
analysis.
Discuss two effects of the environment on physiological processes (for
example, effects of jet lag on bodily rhythms, effects of deprivation on
neuroplasticity, effects of environmental stressors on reproductive
mechanisms)
http://faculty.washington.edu/chudler/plast.html
Examine one interaction between cognition and physiology in terms of
behaviour (for example, agnosia, anosognosia, amnesia)
http://www.holah.co.uk/summary/maguire/