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Biological Level of Analysis

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Session 22 Module Revision
General learning outcomes
 LO1: Outline principles that define the biological
level of analysis
 LO2: Explain how principles that define the
biological level of analysis may be demonstrated
in research
 LO3: Discuss how and why particular research
methods are used at the biological level of
analysis
 LO4: Discuss ethical considerations related to
research studies at the biological level of
analysis.
Physiology and behaviour Learning Outcomes
 LO5: Explain one study related to localization of function
in the brain
 LO6: Using one or more examples, explain effects of
neurotransmission on human behaviour
 LO7:Using one or more examples, explain functions of two
hormones in human behaviour.
 L08 Discuss two effects of the environment on
physiological processes
 LO9 Examine one interaction between cognition and
physiology in terms of behaviour. Evaluate two relevant
studies.
 LO10 Discuss the use of brain imaging technologies in
investigating the relationship between biological factors
and behaviour.
Genetics and behaviour Learning Outcomes
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L011: With reference to relevant research studies,
to what extent does genetic inheritance influence
behaviour?
LO12: Examine one evolutionary explanation of
behaviour.
LO13: Discuss ethical considerations in research
into genetic influences on behaviour.
ethodological considerations
lternative explanations
ender considerations
thical considerations
ultural considerations
Unit 2: Biological LOA
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It is important not just to identify the
consideration, but to clearly link it to either
the study or the bigger question.
You need to explain WHY not just state
strengths and limitations
E.G. The study was unethical BECAUSE....
Unit 2: Biological LOA
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The following slides are merely an overview
of the BLOA
You need to revise in much more depth to
perform well on exam
Any topics you are unsure of go back and
read the full slides
LO1: Outline principles that define the
biological level of analysis??
1.
2.
3.
There are biological correlates of
behaviour
Animal research can provide insight
into behaviour
Human behaviour is, to some extent,
genetically based
Unit 2: Biological LOA
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1.) There are biological correlates of
behaviour Physiological origins of behaviour
Implication is that it should be possible to
link specific biological factor (e.g. a hormone)
and a specific behaviour
Aim of researchers working at the biological
level of analysis
Biological researchers often adopt a
reductionist approach
Unit 2: Biological LOA
2.) Animal Research can provide insight into
human behaviour
Significant amount of research at BLOA uses
animals to study physiological processes
 Assumed that most biological processes in
animals are the same as humans
 One important reason for using animals is that
there is a lot of research where humans
cannot be used for ethical reasons

Unit 2: Biological LOA
3.) Human behaviour is, to some extent,
genetically based
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Behaviour can, to some extent, be explained
by genetic inheritance
RARELY seen as full explanation
Genetic inheritance should be seen as genetic
predisposition-can be affected by
environmental factors
Researchers often use twin studies
Unit 2: Biological LOA
LO2: Explain how principles that define the
biological level of analysis may be
demonstrated in research

For this question you must include the outline
of principles AND an example of research
1.
There are biological correlates of behaviour
2.
Animal research can provide insight into behaviour
3.
Human behaviour is, to some extent, genetically
based
Unit 2: Biological LOA
Newcomer et al. (1999)
 Performed experiment on the role of stress hormone
cortisol on verbal declarative memory
Group 1 high dose
cortisol
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Group 2 low dose
cortisol
Group 3
(control- placebo)
Group 1 showed worst performance on memory task
Shows increase in cortisol has a negative effect on
memory
Unit 2: Biological LOA
•
•
Phineas Gage
Shows there are biological
correlates of behavior
(after his frontal lobe was
damaged his personality
changed
Unit 2: Biological LOA
Rozenweig and Bennet (1972)
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Wanted to study role of environmental factors on brain plasticity with rats
Group 1
Group 2
Enriched environment
Deprived environment
Rats spent up to 60 days in their respective environments before being killed
Brains of rats in group 1 showed a thicker layer of neurons in the cortex than
group 2
Shows that brain grows more neurons if stimulated
Unit 2: Biological LOA
Bouchard et al. (1990)
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
Minnesota Twin Study
Longitudinal study investigating role of genes in IQ**
Monozygotic Twins (MZ) reared
apart
Concordance rate of IQ of 76%

Monozygotic Twins (MZ) reared
together
Concordance rate of IQ of 86%
Shows a link between genetic inheritance and
intelligence but does not rule out the role of
environment
Unit 2: Biological LOA
LO3: Discuss how and why particular research
methods are used at the biological level of
analysis
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BLOA research looks at physiology and genes and
their effect on behaviour
At the BLOA the main research methods used are
experiments and case studies.
Twin studies, adoption studies and family studies
are also used to investigate relationship between
genes and behaviour
Brain imaging technology used to map brain
activity
Lab experiments e.g. Rozenweig and Bennett (1972)
Describe what lab experiment is and provide example
Strengths
 Can be repeated, results tend to be more reliable
 Controlled environment, removes confounding variable
 Isolation of IV and DV give a clear cause and effect relationship
 Can always be generalised to a certain extent
 Data easily measured
Weaknesses of Experiment
 Lab environment, low in ecological validity
 May break ethical guidelines
 Lower generalising potential
 [Natural experiment] No control over variables, unpredictable
 Possibility of Demand characteristics
Case Studies: e.g. H.M. Phineas Gage, Clive Wearing, Genie
Describe what a case study is and provide an example
Strengths
 Unique studies that would otherwise be unethical to do e.g.
Genie
 Less likelihood to break ethical guidelines
 Insight into certain areas of psychology that would otherwise be
difficult to study
 Often leads to in depth data e.g. H.M for 50 years
 High ecological validity
Weaknesses
 Low potential to generalise
 Since it cannot be repeated, results might be unreliable
Twin Studies e.g. Bouchard et al (1990)
Describe method of twin studies and provide example
Strengths
 Twin studies have produced a great deal of data in support of
biological roots of disorders; this has helped psychologists to stress
prevention for those who are vulnerable to such disorders.
 There is a high cross-cultural reliability of concordance levels
Weaknesses
 MZ twins are rarely separated at birth and raised in a totally different
environment, yet this is really necessary to substantiate claims. MZ
twins reared together share many of the same experiences. DZ
twins reared together may not share the same experiences due to
levels of attractiveness or temperament.
Adoption Studies e.g. Horn et al (1979)
Describe method of adoption studies and provide example
Strengths
 Adoption studies allow researchers to isolate variables.
 If a biological mother has no contact since birth and still matches for
a specific trait - for example, the adopted child’s IQ is better than
the adoptive mother and in concordance with the birth mother - this
is strong evidence that genes play a significant role in the
development of this trait
Weaknesses
 Selective placement is a problem. Babies tend to placed with families
similar in background to the natural parents.
 Adopted children – as well as twins - are not representative of all
children.
 The act of being given up for adoption may affect the child’s
behaviour.
LO4: Discuss ethical considerations related to
research studies at the biological level of
analysis.
Can
Do
Can’t
Do
With
Participants
Confidentiality
Deception
Consent
Debrief
Withdrawal
Protection
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Ethical considerations=standards set to prevent
experiments from harming the participants.
Before performing an experiment, researchers must
consider what is appropriate to do to the experiments
in a study.
All research needs to be conducted in a way that
respects the dignity of the participants, whether they
are humans or animals
Sometimes a need to break guidelines
For research purposes, where there are no other
feasible methods
Demand characteristics (mostly with Deception)
Cues in an experiment that tells participants what
behaviour is expected
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Informed consent – participants must be informed about the study and
its procedure and give their formal agreement to participate. This can
be done by use of a contract or other document.
Deception – sometimes deception is necessary because if the
participants knew the true nature of the experiment, it could affect the
results. In general, deception should not be used. However, if it is used,
it must be used with discretion and must not cause any stress to the
participants. If used, the necessity of deception must also be explained
to the participants during the debriefing.
Confidentiality – all information obtained in a study must be kept
confidential. In most situations, all participants must remain
anonymous.
Debrief: Participants must be debriefed as to true purpose of study at
the end of it.
Withdrawal from a study – participants must be made aware that they
have the right to withdraw from the experiment at any time or revoke
their individual data at the end of the study if they wish.
Protection from physical and mental harm – it is unethical for a
researcher to perform an experiment that in any way harms, demeans,
embarrasses, or stresses a participant, or forces them to reveal private
information.
Rosenzweig and Bennett (1972)
 Rats were euthanized to study their brains-cruelty?
 Didn’t use humans so ethical
 But the research provided significant benefit to the understanding of the
effects of the environment on brain plasticity . This knowledge could
benefit humans and other animals
Case study of H.M
 Informed consent issues
 His identity was kept confidential until death
 Ends justify means? Learnt a lot about memory systems
Case study of Genie
 Ethical to study child who has been abused so much?
 Consent issues?
Twin Studies
 Ethical considerations on how twins raised apart are reunited
Ethical Debate:
 Use of PET scans and fMRI scans has helped psychologists identify brain patterns
for dysfunctional behaviours (there is one for alcoholism, schizophrenia,
depression, etc.)
 These patterns are present even if the individual does not show any signs of the
disorder.

Should doctors scan patients to let them know if they have a predisposition (the
brain pattern) for a mental disorder? How would this affect the individual?
1. YES – doctors should inform the patients that their brain scans match that of a
mental disorder, even if that person does not show any symptoms of the disorder.
It would give the individual the signal to monitor themselves and their own
behaviour in case that disorder really does manifest itself within them. As soon as
any symptoms arrive, they will know to seek medical or psychological attention
immediately. Ethically, individuals should have the right to know what conditions
they are at risk for, so that they can be aware and prepare themselves for the
future.
2. NO – the doctors should not inform their patients that their brain scans match that
of a mental disorder. This would only add stress to the individual and may
escalate them into their predisposed condition, especially if that condition is
something like depression. If no symptoms are present, it is unethical to concern
someone with a potential disorder that does not even exist.
LO5: Explain one study related to localization
of function in the brain??


When a behaviour is localised in the brain, it
is possible to trace the origin of a behaviour
to a specific part of the brain
Studies in localisation of function led to the
desire to map out the brain’s functions
Unit 2: Biological LOA
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Paul Broca (1861) Found that people suffering
from damage to their left frontal lobe of the
brain were unable to make grammatically
complex sentences.
This condition is now known as Broca’s
aphasia
Case study of Tan used as evidence
Unit 2: Biological LOA
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First described the area that appears to be
crucial for language comprehension
The left posterior superior temporal gyrus
Wernicke’s patients could produce speech,
but could not understand it
This condition is known as Wernicke’s
aphasia
Unit 2: Biological LOA
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Research undertaken by Broca and Wernicke
provides us with a clear understanding of
some of the factors involved in language
processing
By carrying out post-mortem studies of
people who had suffered from strokes, they
came to the conclusion that language
processing is localised
Unit 2: Biological LOA
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Milner (1957) first to report case
H.M. had anterograde amnesia (failure to store
memories that happened AFTER trauma)
Corkin et al. (1997) MRI scan of H.M.’s brain
Brain imaging allowed researchers to get a
precise image of the brain damage i.e.
hippocampus
Important: provided evidence that there are
different memory systems in the brain
Unit 2: Biological LOA
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Hippocampus plays a critical role in converting memories from
short-term to long-term memory
H.M. had deficits in one part of the memory but not in others is
evidence that the brain has several memory systems supported
by distinct brain regions
H.M. could learn new procedural memories which indicates that
these memories are not stored via the hippocampus
Shows memory processes are much more complex than
originally believed
Although hippocampus is very important in the storage of new
memories it is not the only part of the brain involved in the
process
= Localised parts for different memory systems
Unit 2: Biological LOA
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Ethics: memory to give consent?
Participated in research for 50+ years in many kinds of
tests including cognitive tasks, observations and
neuroimaging studies
Longitudinal case study has contributed enormously to
knowledge of how memory processes are related to
specific areas of the brain:
◦ The hippocampus is important for the forming, organising and
retrieval of memories
◦ Procedural memories are not processed by the hippocampus
Case study it is questionable whether the results can be
generalised to a larger population
HOWEVER...
 Findings from other case studies of people with brain
damage like H.M. tend to support these findings so it may
be possible to generalise the findings to some extent.

Unit 2: Biological LOA
L06: Using one or more examples, explain
effects of neurotransmission on human
behaviour
Examples of neurotransmitters??
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Neurotransmitter= body’s natural chemical messengers
Transmits info from one neuron to another
Our chemical balances/imbalances correlate to specific
human behaviors
Higher or lower levels of certain neurotransmitters and/or
can lead to changes in behavior

These associations are merely correlations, and do not
necessarily demonstrate any cause and effect relationship.

We don’t know what other variables may be affecting both
the neurotransmitter and the behaviour

E.G. We don’t know if the change in the neurotransmitter
causes the illness, or the illness causes the change in the
neurotransmitter.
Unit 2: Biological LOA
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Serotonin?
Serotonin
Unit 2: Biological LOA
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Aim: see how sensory deprivation affects brain
Studied group of Buddhist monks who went on a 72 hour
pilgrimage to a holy mountain
Monks didn’t consume food or water, did not speak
After 48 hours monks had hallucinations often seeing
ancient ancestors or feeling a ‘presence’ by their side
Researchers took blood samples before monks ascended
mountain and again immediately after monks reported
hallucinations
Found serotonin levels had increased in monks’ brains
Unit 2: Biological LOA
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These higher levels of serotonin activated parts of brain resulting
in hallucinations
Concluded sensory deprivation triggered the release of serotonin
which actually altered way that monks experienced the world
Evaluation
 Study on very small group of people who are different to most
hard to generalise
 Monks on a pilgrimage- beliefs may be responsible for
hallucinations
Do NOT use this as your only example. Use it to
showcase your critical thinking abilities
Unit 2: Biological LOA
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Acetylcholine??
Acetylcholine
Unit 2: Biological LOA
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Aim: to determine role of neurotransmitter acetylcholine (ACh)
on memory formation
Procedure: Experimental study using rats. Rats trained to run a
maze.
Group 1
Group 2
Control
Rats injected with scopolamine
(reduces ACh)
Rats injected with physostigmine
(increases ACh)
No injections
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Group 1: problems finding way through maze & made more
mistakes
Group 2: ran quickly through maze & made few mistakes.
Quicker than control group.
ACh linked to memory formation
Unit 2: Biological LOA
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Controlled lab experiment with control group- can establish
cause & effect between ACh and memory
Questionable whether can generalise findings to humans.
HOWEVER, research has shown ACh producing cells are
damaged in early stages of Alzheimer’s
Unit 2: Biological LOA
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Dopamine??
Dopamine
Unit 2: Biological LOA
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Symptoms of schizophrenia include hallucinations, delusions,
thought disturbances
Associated with increased activity at dopamine receptor sites
Antipsychotic (treatment) reduce increased dopamine activity.
Hypothesis based on accidental findings based on drugs that
increase/decrease dopamine activity and reduce/exacerbate
schizophrenia
Examples
 Amphetamines and cocaine, which trigger release of dopamine
have been found to exacerbate the psychotic symptoms in
schizophrenia.
 Another accidental finding is that a drugs which block dopamine
function, such as chlorpromazine reduce psychotic symptoms.
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Evidence= correlational- no cause and effect evidence.
Could be that schizophrenia has caused the abnormal
chemical levels rather than the other way around.
Theories are not based on individual laboratory tests.
Chlorpromazine only stops some symptoms of schizophrenia
such as hallucinations and delusions.
Furthermore Chlorpromazine makes little or no difference to
30% of schizophrenics. DOPAMINE can’t be only cause.
Drugs have their effect on the brain almost immediately, but
take weeks to affect behaviour of the patients. Hypothesis is
unable to explain this delay.
•Practical application of neurotransmitter research has improved the
lives of many people suffering with NTS related disorders: Drugs have
been developed to either stimulate the neurotransmitter if there’s not
enough or block the site if it is excessive Has been criticised of
reducing explanations of behaviour to workings of neurotransmitter
alone (reductionist)
•Can a complex human behaviour like attraction to a potential partner
be attributed solely to dopamine? Can mood be simply attributed to
serotonin levels?
Psychologists consider that neurotransmitters play a role but do NOT
solely rely on neurotransmission on behaviour
Neurotransmitter: A chemical in the synapse that
transmits signals between neurons
Hormone: A chemical secreted by an endocrine
gland. Travels through the bloodstream. Usually
involved in longterm functioning of the body.
LO7: Explain, using examples, functions of two
hormones in human behaviour?
LO7: Explain, using examples, functions of two
hormones in human behaviour
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Hormones are chemicals that affect behavior.
They are produced by the glands that make up the endocrine system
Hormones are a contributing factor to behavior.
No modern psychologist suggests that hormones are the only factor
explaining human behavior.
1. Oxytocin
2. Melatonin
3. Cortisol
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Plays role inducing labour & lactation
Released with touches & hugs
Associated with bonding between mother & child and
bonding between lovers
Oxytocin linked to trusting other people
Experimental manipulation of oxytocin levels has
shown increase in trust
Suggested trust has an
evolutionary basis
Aim: Investigate role of oxytocin after breaches of trust in a trust game
Procedure:

Participants played trust game

The “investor” (player 1) receives a sum of money and must decide whether to keep it or
share it with a “trustee” (player 2). If sum is shared sum is tripled. Then player 2 (trustee)
must decide if this sum should be shared (trust) or kept (violation of trust)

fMRI scans were also carried out on participants
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Participants received either oxytocin or placebo via a nasal spray
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In 50% of games trust was broken
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They received feedback on this from experimenters during the games
Placebo Group
Oxytocin Group
Less likely to show trust after feedback
on betrayal. They invested less.
Continued to invest at similar rates even
after receiving feedback on a breach of
trust
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Oxytocin could explain why people are able to
restore trust and forgive in long term
relationships
fMRI research merely mapping brain activity but
nothing definite can be said about what it really
means with current technology
Giving oxytocin like this in an experiment may
not reflect natural physiological processes.
Function of oxytocin=very complex and too
simplistic to say it’s the “trust hormone”
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Production of melatonin by pineal gland is stimulated
by darkness and inhibited by light
Melatonin release correlates with the circadian
rhythm (the biological clock that is based on a 24
hour day/night cycle)
It is suggested that taking melatonin in the early
evening may improve one’s ability to fall asleep
Through study of melatonin researchers hope to find
a solution for those who suffer from insomnia and jet
lag
Rosenthal (1987)
 Evidence suggests higher levels of melatonin
contribute to seasonal affective disorder (SAD)
 SAD= subcategory of depression characterised
by sleepiness, cravings for carbs & lethargy
 Reduced levels of sunlight in winter believed to
disrupt circadian rhythm leading to this
depression
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As increased sunlight improves the symptoms, phototherapy (prolonged
exposure to bright light) often main treatment for people with SAD
Despite some claims success, there is lack of definitive evidence of its
effectiveness
One has to be careful about seeking quick
solutions to complex questions
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Produced by the adrenal cortex in response to stress to restore
homeostasis (the body’s normal balance)
Chronic stress may result in prolonged cortisol secretion.
Can result in physiological changes such as damaged immune
system and impairment of learning and memory
This is because high amounts of cortisol results in deterioration of
the hippocampus (Sapolsky, 1996)
N.B. Also used as example for principle of BLOA “there
are biological correlates of behaviour
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Aim: To investigate how levels of stress hormone cortisol interfere
with verbal declarative memory
Design: Randomised, controlled, double blind experiment that ran for
four days
Participants: self selected sample (recruited through advertisement) of
51 normal & healthy people aged 18-30
Group 1 (high dose)
Group 2 (low dose)
Tablets containing
160mg of cortisol for 4
days (equivalent to
cortisol levels in blood
as a consequence of
major stressful event)
Tablets containing
40mg of cortisol for 4
days (equivalent to
cortisol levels in blood
as a consequence of
minor stressful event)
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Group 3
(control)
Placebo Tablets
(tablets with no active
ingredient)
Participants listened to a prose paragraph and had to recall is
as a test of verbal declarative memory
Group 1 showed worst performance on task
Group 2 showed no memory decrease
Shows that an increase in cortisol has a negative effect on
memory
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Controlled randomised experiment so possible to
establish cause and effect relationship between
levels of cortisol and scores on verbal declarative
memory test
The negative effects of taking cortisol was
reversible so no harm was done
L08 Discuss two effects of the environment on
physiological processes
1.
2.
Environmental effects on brain plasticity
Environmental stressors and physiological
processes
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Brain plasticity =brain's ability to change as a result of experience.
Experiences are processed in the brain’s nervous system, and
stimulating environments will result in increased numbers of
synapses (brain plasticity).
Environmental stimulation refers to the way the environment
provides stimulation in the form of social interaction and learning
opportunities for animals and humans.
Enriched environment=multiple opportunities to learn new things.
Researchers used animal models to study synaptic changes in the
brain because it is not possible to use humans in deprivation
experiments.
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60 days stimulating
environment vs control
Findings: Post mortem
studies of rats´ brains
showed that those that
had been in a
stimulating environment
had an increased
thickness in the cortex.
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Rigorously controlled laboratory= possible to establish a cause-effect relationship.
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Research challenged the belief that brain weight cannot change= important finding.
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Ethical issues?
◦ BUT results contributed to better understanding of the role of environmental
factors in brain plasticity it can be argued that the research was justified in spite
of the ethical issues.
Can we really generalise results from animal studies to humans?
L08: Discuss two effects of the environment on physiological processes
1. Environmental effects on brain plasticity
Case studies of neglected children are used to
look at environmental effects on brain plasticity
Perry (1997)
 Brain scans of three year olds who had a normal
upbringing and those who were severely neglected
 Found differences in brain size and development
L08: Discuss two effects of the environment on physiological
processes
1. Environmental effects on brain plasticity
Curtis (1977) Case study of Genie
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Neglected until found at the age of 11.
Although tests showed that she was highly intelligent, her
language abilities never progressed beyond those of a third
grader.
Suggested by some that environmental deprivation led to
permanent effects on development of brain and thus abilities
L08: Discuss two effects of the environment on physiological processes
1. Environmental effects on brain plasticity
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Could have practical applications for treating other cases
1 person not generalisable; personal brain structure & no
control on variables.
Later studies show critical periods favourable to behaviour
but plasticity throughout life (Gage 2002).
Other neglected children have been able to develop language
Ethical issues???
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Environmental stressor= any stimulus from environment that
affects the condition of someone and may cause abnormality in
their physiological responses.
E.g. toxins, viruses, drugs, noise, temperature, traumas, abuse,
workplace stress and life events such as relationships,
jobs and school.
Some research to show environmental stressors can lead to
physiological changes
L08: Discuss two effects of the environment on physiological processes
2. Environmental Stressors and Physiological Processes
Bremner et al (2003) Stress & PTSD
 Aim: Measure volume of hippocampus based on the theory that
prolonged stress may reduce the volume of the hippocampus due
to increased cortisol levels.
 Procedure: MRI scans of the brains of the participants and
participants completed memory tests
 Participants= veterans and female adults who had experienced
early childhood sexual abuse. Some had developed PTSD, but not
all.
 Results: found deficits in short-term memory and that the
hippocampus was smaller in PTSD patients than in a control group.
The veterans with most memory problems had the smallest
hippocampus. The findings showed a clear correlation between
number of years of abuse as measured by a trauma test, memory
problems and hippocampal volume. STRESSFUL EVENT LED TO
SMALLER HIPPOCAMPUS
L08: Discuss two effects of the environment on physiological
processes
2. Environmental Stressors and Physiological Processes
Bremner et al (2003) Evaluation
 The sample=very small so it is difficult to say anything definite
about relationship between trauma and hippocampal volume.
 Could be alternative explanations to differences in hippocampal
volume (e.g. that people who suffer from PTSD often suffer
from depression as well). Depression is also associated with
reduction of the hippocampus.
 findings of a large reduction of hippocampal volume in
combat-related PTSD has been replicated many times.
 Understanding which parts of the brain may impact PTSD can
lead to the development of better, more
effective medications for the treatment of PTSD.
L08: Discuss two effects of the environment on physiological
processes
2. Environmental Stressors and Physiological Processes
Kiecolt-Galser et al (1984) Exam Stress and Immune System
Aim: Investigate the stress from exams and its effect on the immune system.
Procedure:
 75 first year medical students (49 males, 26 females).
 Blood samples were taken before and during exams.
 Immune functioning was assessed by measuring the T-cell activity in the blood
 Students given survey for self assessment on other psychological variables e.g. Loneliness
Results
 Samples taken during exams= weaker immune system
 Students that claimed that they felt lonely in the survey = more vulnerable immune
system.
Conclusion:
 Exam stress decreases the functionality of our immune system.
 Immune functioning is also affected by psychological variables.
These long term stressors may make individuals more
vulnerable to the effect of short term stressors such as
exams.
L08: Discuss two effects of the environment on physiological
processes
2. Environmental Stressors and Physiological Processes





Confounding variables: No control over other factors that might
have affect immune system e.g. drugs, diet, sleep etc
Correlational study: cannot identify cause and effect relationship.
Did stress cause sickness? Or did sickness cause stress?
Uses measurable, quantitative evidence (t cell blood count).
Unrepresentative sample (all medical students) and so the results
cannot be generalised to other groups.
The study uses data that is open to
interpretation (questionnaire)
LO9 Examine one interaction between
cognition and physiology in terms of
behaviour. Evaluate two relevant studies.
What
cognitive
process
did we
look at?
LO9 Examine one interaction between
cognition and physiology in terms of
behaviour. Evaluate two relevant studies.
Physiology (brain damage) and cognition
(amnesia)
LO9: Examine one interaction between cognition and
physiology in terms of behaviour. Evaluate two relevant studies.
Cognition?


Cognition= mental process of acquiring and processing
knowledge and understanding through thought,
experience and the senses.
Includes perception, attention, language, memory and
thinking.
Physiology?

Physiology is the internal, biological mechanisms of living
organisms – the way the organism functions
LO9: Examine one interaction between cognition and
physiology in terms of behaviour. Evaluate two relevant
studies.


Amnesia = condition in which people lose their ability to
memorize/recall information.
There is an interaction between biological and cognitive
factors in amnesia
Amnesia can have a biological cause (e.g. brain damage) and
affects cognition (e.g. memory)
1. Anterograde Amnesia
 Impairment in ability to recall new information after onset
 Inability to form new memories
 Antero = new
2. Retrograde Amnesia
 Impairment in ability to recall old
information before the onset
 Inability to recall old memories
 Retro = old
LO9: Examine one interaction between cognition and
physiology in terms of behaviour. Evaluate two relevant
studies.
Study 1: Milner (1957) H.M
HM had anterograde amnesia – unable to create new memories .
 MRI Scan Results (Corkin, 1997) – Brain damage was pervasive and included the
hippocampus, the amygdala, and other areas close to the hippocampus.
Conclusion:
 The hippocampus is needed for memories to be transferred to long-term
memory.

Connection to question
 Case of HM reveals the interaction of cognition (memory) and physiology (brain
damage in the hippocampus) in amnesia.
◦ Brain damage in relevant areas caused memory impairment
◦ Study suggests that certain brain regions are responsible
for the cognitive process of memory
LO9: Examine one interaction between cognition and physiology in
terms of behaviour. Evaluate two relevant studies.
H.M Case study evaluation
LO9: Examine one interaction between cognition and
physiology in terms of behaviour. Evaluate two relevant
studies.
Study 2: Sacks (2007) Clive Wearing
 Clive Wearing-viral infection (encephalitis) left with serious brain
damage in the hippocampus (biological cause), which caused memory
impairment (effect on cognition)
 He suffered from anterograde and retrograde amnesia
 Could not transfer information from STM to LTM.
 MRI scans of Wearing’s brain showed damage to the hippocampus
and some of the frontal regions.
Conclusion:
 The case of Clive Wearing provides insight into the biological
foundation of different memory systems, which is a cognitive
process.
 Highlights interaction between cognition and physiology as
establishes the link by illustrating the effect of physiological causes in
the brain (brain damage occurring in hippocampus region, on the
social and cognitive interactions of the individual
LO9: Examine one interaction between cognition and
physiology in terms of behaviour. Evaluate two relevant
studies.
Evaluation of Clive Wearing Case study
 In amnesia patients, damage to certain brain areas
impairs patients' memory, therefore supporting the
idea of the interaction between the physiology (of the
brain) and cognition (of memory) in amnesia.
 Therefore, amnesia has a bidirectional relationship
between its physiological cause occurring in the brain
and the cognitive process of memory.
LO10: Discuss the use of brain imaging
technologies in investigating the relationship
between biological factors and behaviour.
Can you name
two brain
imaging
technologies?
LO10: Discuss the use of brain imaging technologies in
investigating the relationship between biological factors
and behaviour.



Modern technology extensively used in
neuropsychology
Allows researchers to:
◦ Study active brain
◦ See where specific brain processes take place
◦ Enables localisation of function in LIVING brain
Modern researchers use brain imaging techniques to
investigate relationship between behaviour and brain
structures
1.
2.
3.
4.
Electroencephalogram (EEG)
Positron Emission Topography (PET)
Magnetic Resonance Imaging (MRI)
Functional Magnetic Resonance Imaging (fMRI)
LO10: Discuss the use of brain imaging technologies in
investigating the relationship between biological factors
and behaviour.
Image often thought of as ‘brain waves’
 When neurons transport information through the brain, they have an
electrical charge
 Registers patterns of voltage change in the brain
 Psychologists have gained better understanding of behaviours as diverse
as sleep, emotions & epilepsy
 Provides limited information- cannot reveal what’s happening in deeper
brain regions; nor can it show actual
functioning of brain

LO10: Discuss the use of brain imaging technologies in
investigating the relationship between biological factors and
behaviour.
Monitors glucose metabolism in brain
 Patient injected with harmless dose of radioactive glucose
 Radioactive particles
detected by PET scanner
 Used to diagnose
abnormalities like tumors,
Alzheimer’s,
schizophrenia etc

LO10: Discuss the use of brain imaging technologies in
investigating the relationship between biological factors and
behaviour.


Uses magnetic field and radio waves to create
detailed images of body.
Gives detailed pictures of internal structures
in brain
LO10: Discuss the use of brain imaging
technologies in investigating the relationship
between biological factors and behaviour.




Used MRI to investigate whether substance abuse (marijuana)
can damage developing brain of young adults
Scan indicated there were brain abnormalities in frontal,
parietal and temporal regions in brain of marijuana users
Development of white matter (myelin) was affected could
explain slow information processing in brain
Concluded early marijuana use can affect brain development
but as study gives correlational data more research is needed
LO10: Discuss the use of brain imaging technologies
in investigating the relationship between biological
factors and behaviour.
Case study of H.M.

Corkin et al (1997) did MRI scan of H.M’s
brain which allowed for precise picture of
brain damage. Confirmed that hippocampus
was missing- able to link to memory.
LO10: Discuss the use of brain imaging technologies in
investigating the relationship between biological factors and
behaviour.






MRI scans show how blood flows in brain and can be used to identify
problems with blood circulation. Can be used for early detection of
Alzheimer’s
Safe to use-no radioactive material is used
Scanner not a natural environment for cognition- ecological validity?
Very expensive
Movement may affect images
Cannot say anything about cause and effect relationships, only
provide correlational data
LO10: Discuss the use of brain imaging technologies in
investigating the relationship between biological factors and
behaviour.




Scanner measures changes in blood flow in active brain
Blood flow associated with use of oxygen and neural
activity during information processing
When participants are asked to perform a task, scientists
can observe the part of the brain that corresponds with
that function
Use increased vastly over past ten years and now widely
used by cognitive neuroscientists
LO10: Discuss the use of brain imaging technologies in
investigating the relationship between biological factors
and behaviour.







Aimed to find biological correlates of stereotypes and prejudice
Studied brain processes as a response to extreme outgroups
Scanned students’ while watching pictures of different humans or
objects
Predicted that prefrontal cortex would be active when students
looked at humans but not objects
This was found EXCEPT when students looked at pictures of extreme
outgroups e.g. Homeless and addicts
Brain regions linked to disgust were then activated and there was no
activity in prefrontal cortex
Concluded this indicated a dehumanisation of outgroups. These
groups apparently viewed as ‘disgusting objects’ rather than people
LO10: Discuss the use of brain imaging technologies in
investigating the relationship between biological factors and
behaviour.
Baumgartner et al (2008) Oxytocin and Trust



fMRI scans carried out on participants
In oxytocin group cans showed decreases in
responses in amygdala (involved in emotional
processing) and caudate nucleus (involved in
learning to trust)
Explanation for behaviour in trust game
LO10: Discuss the use of brain imaging technologies in
investigating the relationship between biological factors
and behaviour.









One of most frequently used technologies in biopsychological research
today
Shows actual brain activity and indicates which areas of brain are
active
Scans have higher resolution than PET scans and are easier to carry out
Does not use radioactive substances
Can record activity in all regions of brain
Focus mostly on localised functioning in brain and does not take into
account the distributed nature of processing in neural networks
Results are correlational so not possible to establish cause and effect
relationships
Scanner not a natural environment for cognition- question of
ecological validity
Brain areas activate for different reasons- e.g. Just because amygdala
lights up does not necessarily mean fear is the response being
observed
L011: With reference to relevant research
studies, to what extent does genetic
inheritance influence behaviour?
L011: With reference to relevant research
studies, to what extent does genetic
inheritance influence behaviour?
1.
State what you are doing in the essay:
◦ Essay will attempt to consider the merits or
otherwise of the influence of genetic
inheritance on behaviour.
2.
Outline the overarching principle:
◦ According to 3rd principle of BLOA, behaviour
is innate and inherited because it is
genetically based (we are predisposed to a
specific behaviour due to genetics).
L011: With reference to relevant research studies, to
what extent does genetic inheritance influence
behaviour?
3.
Genetics and the importance of research into genetics:
◦ Argued that people have a genetic predisposition.
◦ Genes=segments of DNA inherited by the offspring from the
parent.
◦ Behavioural Genetics= understanding of how genetics and
environment contribute to individual variations in human
behaviour, where the premise is that inheritance of DNA influences
behaviour.
◦ But genetics alone does not affect behaviour- environmental
factors
◦ Genes=complex
 Unlikely that single gene is responsible for complex behaviours
4.
Type of studies used in genetic research
◦ Twin studies
 study the correlation between genetic inheritance and behaviour due to the
common genetics shared by twins.
 Monozygotic twins (MZ) identical - share 100% genetic material.
 Dizygotic twins (DZ) fraternal - share 50% genetic material.
 Usually further explored, by studying the twins either separated or together
to make a correlation of their behaviour.
◦ Adoption studies
 Allow researchers to study the comparison between genetic and environmental
influence on behaviour.
 Adopted children share no genes with their adoptive parents but 50% of genes
with their biological parents.
◦ Family studies
 Study behaviour between family members who have similar genetics to
different degrees. Inheritance
L011: With reference to relevant research studies, to
what extent does genetic inheritance influence
behaviour?
5.
Outline behaviour you are looking at: Intelligence
◦ Intelligence = aspect of behaviour studied in relation
to genetics.
◦ Questioned whether intelligence was attributed to
genetic or environmental factors. Intelligence is
difficult to define
◦ IQ tests developed to measure of intelligence and are
used in much psychological research.
L011: With reference to relevant research studies, to
what extent does genetic inheritance influence
behaviour?
Bouchard and McGue (1981)
 Conducted meta-analysis of 111 studies of siblings.
 Investigated IQ correlations between siblings.
 Positive correlation between kinship and IQ correlation - the closer the
siblings were, the more similar their IQ.
Evaluation
◦ Large study= generalisable.
◦ Siblings are raised in the same environment, so influence may not be
purely genetic,
◦ The further apart the siblings in age, the less correlated their IQs weresuggests environment
In order to investigate the role of genetics by itself, identical twins that are
raised separately from birth must be studied. Identical twins have a
100% genetic relationship, but if raised in separate environments, any
similarity (beyond that expected by chance) in IQ must be due to
similarity in genetics.
L011: With reference to relevant research studies, to
what extent does genetic inheritance influence
behaviour?
Bouchard et al. (1990) - Minnesota Twin Study





Conducted longitudinal study since 1979, comparing MZA twins to MZT
twins in terms of intelligence (MZA - monozygotic raised apart, MZT monozygotic raised together)
Each twin completed 50 hours of testing
Cross cultural study, using participants from all over world.
Concordance Rates of intelligence
Same person
87%
MZA
86%
MZT
76%
DZT
55%
Siblings reared
together
47%
Bouchard et al. concluded a heritability estimate of 70% - 70% of
intelligence can be attributed to genetic inheritance. 30% attributed to
other factors.
L011: With reference to relevant research studies, to
what extent does genetic inheritance influence
behaviour?
Bouchard et al. (1990) - Minnesota Twin Study
•Concordance rate between twins shows that their behaviour was
affected mostly (70%) by genetics, rather than the environment, where
the other 30% may be attributed to other factors in the surrounding
environment.
Evaluation
•Size of the study means it is more generalisable
•Nature of sample - cross cultural
•Mean age of participants 41 years, as opposed to previous studies with
adolescents
•Relied on media coverage to recruit participants
•Ethical concerns with the way twins were reunited
•Frequency of contact between twins prior to study not controlled.
•'Equal environment assumption' - twins reared together may not have
experienced the same environment.
L011: With reference to relevant research studies, to
what extent does genetic inheritance influence
behaviour?
Horn et al. (1979)
 Conducted study on parents who raised BOTH adopted and natural children.
 All children had same upbringing, therefore same environment
 Found no significant differences in correlation of parent-child IQs between natural
and adopted children.
 Conclusion that genetics has little impact - mostly environment.
Niche Picking Hypothesis Scarr and McCartney (1983)

Horn et al (1979) findings could be explained by the “niche picking hypothesis”
proposed by Scarr and McCartney (1983)
◦ Genes affect an individual’s preference for particular environments
◦ Environment then affects the development of the individual.
◦ Genetically similar people will tend to select similar environments, thus leading to
similar IQ.
◦ It is possible that genetic predisposition influences individuals to tend towards
environments that accentuate that disposition, thus leading to increased
heritability throughout their lifespan.
◦ The niche picking hypothesis supports the influence of genetics on IQ.
L011: With reference to relevant research studies, to
what extent does genetic inheritance influence
behaviour?
Genetics can influence intelligence as shown by supporting studies on
influence of genetics.
Horn (1979) provided findings to suggest that the environmental factor
affects intelligence - adopted children have a higher IQ correlation with
the adoptive family, rather than biological family.
Genetic inheritance influences intelligence, and thus behaviour, to a great
extent large amount of supporting research the niche picking hypothesis
refutes environmental factors
Although important to note role of genetics in determining human
behaviour is significant, essential to bear in it is not a simple causal
relationship, as other factors such as the environment can influence thus
alter certain behaviour.
LO12: Examine one evolutionary explanation
of behaviour.
What
behaviour
did we
look at?

Principle of evolutionary psychology=as genes mutate, those that are
advantageous are passed down through a process of natural selection.



Derived from Charles Darwin's theory of evolution.
Evolutionary psychologists attempt to explain how human behaviours
have developed over time.
The behaviour which will be examined in terms of an evolutionary
explanation of behaviour is the study of emotions, in particular disgust.
•Ekman (1972), found facial expression for disgust identical in
different cultures.
•Facial expression also produced in blind individuals and is correctly
interpreted by individuals born deaf.
•This evidence indicates an innate biological basis for the expression
and recognition of disgust.
• This evidence suggests that disgust is experienced and recognized
almost universally and strongly implicates its evolutionary
significance.
Fessler 2006 Disgust in pregnant women
Aim: investigate whether ‘morning sickness’ experienced
by pregnant women has evolutionary basis.



Investigated women's experiences of nausea during pregnancy
During 1st trimester, hormones suppress immune system to accustom
the body to the foreign genetic material growing in womb.
Hypothesised that heightened sense of disgust experienced by women
during this time was the body's way of compensating for the lacking
immune system.
Fessler 2006 Disgust in pregnant women



496 healthy pregnant women
The women asked to consider 32 stomach churning scenarios such as:
Walking barefoot and stepping on an earthworm
Maggots on a piece of meat in a outdoor trashcan
Before asking the women to rank disgusting scenarios (using a survey),
answered a survey to measure morning sickness
Findings & Conclusions:




Women
in 1st trimester scored much higher on disgust sensitivity than those in
the 2nd and 3rd trimester.
They found the scenarios involving food most disgusting.
As many of most harmful diseases are food-borne, concluded that heightened
sense of disgust was advantageous to ancestors and allowed them to survive to
produce offspring
Would have helped compensate for the increase susceptibility to disease during
early pregnancy due to the suppressed immune system
Fessler 2006 Evaluation




Study supports the role of disgust in aiding reproduction, and
thus, as an evolutionary behaviour.
Data collected through questionnaires. Self reports may not be
a great way of measuring disgust.
Better to confront them with real disgust-eliciting objects.
Effect was big (but not hugely significant when using statistical
significance).
Supports that disgust may be an evolutionary behaviour as it
may assist reproduction of offspring and protection against
disease
Curtis et al (2004): Internet survey on disgust




Research on the Internet to test whether there were
patterns in disgust responses
Online survey: participants were shown 20 images &
asked to rank their level of disgust.
Among images were 7 pairs in which one was potentially
harmful to the immune system, and other was visually
similar but non-infectious e.g. one pair was a plate of
bodily fluids and a plate of blue viscous liquid.
77 000 participants from 165 countries.
Curtis et al (2004): Internet survey on disgust
•Disgust reaction most strongly elicited for images which threaten
immune system.
Natural selection may have helped ancestors to be more disgusted at
things which threatened the immune system
•Women had higher disgust reactions than men.
As women are carriers for offspring, they have a stronger disgust
reaction so as not to threaten the lives of unborn offspring.
•The disgust reaction also decreased with age.
The decrease of disgust with age may be explained by the fact that the
older a member of a species, the less likely they are to reproduce.
Curtis et al (2004) Evaluation
•77 000 participants from 165 countries. Large sample size and
cross cultural = generalisable
•Provides support for Fessler et al (2005) and vice versa
•Self report measures of disgust = subjective
Link back to question: Curtis (2004) study supports the role of
disgust in aiding reproduction, and thus, as an evolutionary
behaviour.
Evaluation of Evolution of disgust
•The theories = speculative – its difficult to carry out experiments to
clearly prove the theories
• Since it may be difficult to test empirically some evolution-based
theories, researchers may be susceptible to confirmation bias— that is,
they see what they expect to see. Hayes (2005) states that there is a
tendency to ignore findings that don’t fit in with the theory confirmation
bias
• Little known about behaviour of early Homo sapiens, so statements
about how humans used to be= hypothetical.
•There is some evidence to support evolutionary explanation of disgustFessler (2006) and Curtis et al (2004)
• Evolutionary arguments often underestimate the role of
culture/nurture/the present environmental influences in shaping behavior.
LO13: Discuss ethical considerations in
research into genetic influences on
behaviour.




Research into human genetics aims to determine the influence of genes
on behaviour and identify genes involved in hereditary diseases and
disorders.
This kind of research may pose risks to participants because there are
consequences for any individual, and their family, who finds out that
they have a genetic predisposition to a disorder or behaviour that is
harmful.
In psychology, ethics must be considered to ensure participants (humans
and animals) are not harmed and that research conducted is ethically
valid.
Ethical considerations in research into genetic influences on behaviour
include:
◦
◦
◦
◦
revelations of carrying genes for genetic conditions
informed consent for genetic research
confidentiality of participants
stigmatization of individuals on basis of knowledge of genetic conditions
1) Revelations of carrying genes for genetic conditions
 Explain ethical consideration:
◦ E.g. evidence of unrevealed adoptions or discovery that the participant carries the
gene for a particular genetic disorder.
◦ Genetic research can reveal unexpected information that may harm participants
Supporting Study 1: Nurnberger and Gershon (1982)
 A study which shows revelations of carrying genes linked to depression
 Method: Reviewed the results of seven twin studies.
 Results: Concordance rate – correlation – for major depressive disorder
was consistently higher for monozygotic twins (MZTs) than dizygotic
twins.
Ethical considerations:
 Knowledge of a genetic predisposition to depression may cause people
undue stress as they may fear the onset of the disorder.

Self-fulfilling prophecy: If one MZT has depression, their twin may
express the self-fulfilling prophecy and demonstrate symptoms of
depression as well.
2) Informed consent for genetic research
Explain ethical consideration:
◦ It is important, especially for genetic research that the individual must be specifically informed about
the true aims of the experiment and must require consent from the person involved and or from the
parent/family guardians responsible for them before commencement of research.
◦ Uninformed consent may lead to serious a problem if the study proves to be controversial, which, for
example, is demonstrated by...
Supporting Study 2: Dr. Money (1974)

Background: Money was contacted by parents of identical twin boys, one of whom (Bruce) had his penis
burnt off in a circumcision accident. Money advised parents to castrate Bruce and turn him into a girl
(Brenda).
Ethical considerations:

Genetically, Brenda was still a boy, but she was lied to and forced to live as a girl without informed
consent.

In genetic research, there is a risk that participants may learn something about themselves they are not
prepared to deal with.

◦ Counselling should be offered as part of a full debriefing to genetic studies.
◦ Neither Brenda nor her parents were debriefed about the case study that the twins were involved in.
Money used this case as a study for his publication without knowledge of the parents
◦
◦
◦
violation of informed consent
deception
lack of confidentiality and privacy


3) Confidentiality of participants
Participants should know how their privacy and confidentiality will be
protected, and what will happen to any information obtained from the
study.
◦ As there might be consequences for any individual who finds out that they have a
genetic predisposition to a disorder or behaviour, which they might consider
unpleasant or harmful.
◦ Additional problems include future disadvantages regarding work and applying for
other things – where the knowledge of a person’s genetic disorder or behaviour by
other parties, such as insurance companies, who might prevent a person from
receiving life insurance, or employers, who might refuse employment due to this
regard.

Confidentiality and privacy of participants can be protected by:
◦ Coding information (so that only a small number of researchers have access to the
information)
◦ Fully anonymizing the sample (where researchers cannot link results to particular
participants).


Anonymizing the sample can limit the scientific value of the study by preventing follow
up investigation.
But it protects participants from insurance companies, employers, police, and others.
4) Stigmatization of individuals on basis of knowledge of genetic conditions

If other people know about an individual’s genetic predisposition to a disease, the individual can
be stigmatized.

Stigmatization is another ethical consideration as it may lead to institutionalisation and
differential treatment from others.
◦
◦
For example, an insurance company may deny insurance to individuals due to a genetic predisposition of a
disease.
Or employers might refuse employment.
Supporting Study 4: Caspi et al. (2003)
Method:

1037 adults aged 26 years

Researchers assessed the participants? tendency to depression via self-reports
Results:

Variation in the 5-HTT gene moderates the influence of stressful life events on major
depression

Researchers attempted to establish a correlation between the gene and the condition
Ethical considerations:

Stigmatization
◦
◦
Participants may be stigmatized due to their genetic predisposition for major depression
Other people may not wish to be around individuals with a genetic predisposition for a disorder or disease
Conclusions
 It is important to carry out, implement and consider
ethical implications before commencement of
research, especially into genetic research as there are
many controversial consequences which could occur
if not carried out properly.

Ethics should always be considered in research to
protect individuals and avoid harming participants.

Research in psychology should always be critically
evaluated for ethical issues.
Good luck and remember...
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