session 22 module revision. general learning outcomes lo1: outline principles that define the...

Biological Level of Analysis

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.

BLOA Learning Outcomes

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

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.


Unit 2: Biological LOA

EVALUATING STUDIESMethodological considerations

Alternative explanations

Gender considerations

Ethical considerations

Cultural considerations


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....

DO DO YOU BELIEVE IN MAGEC?

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

Please note

LO1: Outline principles that define the biological level of analysis??


1. There are biological correlates of behaviour

2. Animal research can provide insight into behaviour

3. Human behaviour is, to some extent, genetically based

LO1: Outline principles that define the biological level of analysis


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


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




3.) Human behaviour is, to some extent, genetically based

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


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

LO2: Explain how principles that define the biological level of analysis may be demonstrated in research

Research to demonstrate

it??


Newcomer et al. (1999) Performed experiment on the role of stress hormone

cortisol on verbal declarative memory

Group 1 showed worst performance on memory task Shows increase in cortisol has a negative effect on

memory

LO2: Explain how principles that define the biological level of analysis may be demonstrated

in research

1.) There are biological correlates of behaviour

Group 1 high dose cortisol

Group 2 low dose cortisol

Group 3(control- placebo)


• Phineas Gage

• Shows there are biological correlates of behavior (after his frontal lobe was damaged his personality changed


1.) There are biological correlates of behaviour

Rozenweig and Bennet (1972)

Wanted to study role of environmental factors on brain plasticity with rats

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


2.) Animal Research can provide insight into human behaviour

Group 1 Group 2Enriched environment Deprived environment



Bouchard et al. (1990) Minnesota Twin Study Longitudinal study investigating role of genes in IQ**

Shows a link between genetic inheritance and intelligence but does not rule out the role of environment


3.) Human behaviour is, to some extent, genetically based

Monozygotic Twins (MZ) reared apart

Monozygotic Twins (MZ) reared together

Concordance rate of IQ of 76% Concordance rate of IQ of 86%

LO3: Discuss how and why particular research methods are used at the

biological level of analysis

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 measuredWeaknesses 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, GenieDescribe 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 levelsWeaknesses 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.

C a n D oC a n ’ t D oW i t h P a r t i c i p a n t s


C o n fi d e n t i a l i t yD e c e p t i o nC o n s e n tD e b r i e fW i t h d r a w a lP r o t e c t i o n


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


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 systemsCase 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


Studies at BLOA with ethical considerations

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

LO5: Explain one study related to localization of function in the brain

Localisation?


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



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


Carl Wernicke (1874)


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


Broca and Wernicke


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

LO5Explain one study related to localization of function in the brain

The case study of H.M.


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


What can be learned about localisation of brain from H.M.


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.


Evaluation of H.M.

L06: Using one or more examples, explain effects of neurotransmission

on human behaviour

Examples of neurotransmitters??


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.

L06: Using one or more examples, explain effects of neurotransmission on human

behaviour

Serotonin?


Mood

Sleep

Serotonin

Undersupply linked to OCD,

depression, suicide


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

L06: Using one or more examples, explain effects of neurotransmission on human

Kasamatsu and Hirai (1999)


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

hallucinationsDo NOT use this as your only example. Use it to

showcase your critical thinking abilities

L06: Using one or more examples, explain effects of neurotransmission on human behaviour

Kasamatsu and Hirai (1999)

Acetylcholine??


Muscle action Memory

Undersupply linked to

Alzheimer’s

Acetylcholine


Aim: to determine role of neurotransmitter acetylcholine (ACh) on memory formation

Procedure: Experimental study using rats. Rats trained to run a maze.

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


Martinez and Kesner (1991)

Group 1 Group 2 Control

Rats injected with scopolamine (reduces

ACh)

Rats injected with physostigmine (increases ACh)

No injections


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


Evaluation of Martinez and Kesner (1991)

Dopamine??


Movement

Feelings of Pleasure

Dopamine

Excess linked to Schizophrenia

Addiction

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.

Dopamine Hypothesis


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.

Evaluation Dopamine Hypothesis



Evaluation of NTS on behaviour

•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

Can you remember the differenceBetween

neurotransmitters and hormones?

Hormones and Neurotransmitters

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?

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.Oxytocin2.Melatonin3.Cortisol

LO7: Explain, using examples, functions of two hormones in human behaviour

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


Oxytocin

Aim: Investigate role of oxytocin after breaches of trust in a trust gameProcedure: 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 Participants received either oxytocin or placebo via a nasal spray In 50% of games trust was broken They received feedback on this from experimenters during the games


Oxytocin & Trust: Baumgartner et al. (2008)

Placebo Group Oxytocin GroupLess 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

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”

LO7: Explain, using examples, functions of two hormones in human behaviour?

Evaluation: Baumgartner et al. (2008)

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


Melatonin

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


Melatonin & SAD

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


Melatonin & SAD Evaluation

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)


Cortisol

N.B. Also used as example for principle of BLOA “there are biological correlates of behaviour

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


Cortisol: Newcomer et al (1999)

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


Cortisol: Newcomer et al (1999)Group 1 (high dose) Group 2 (low dose) Group 3

(control)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)

Placebo Tablets(tablets with no active ingredient)

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


Evaluation of Newcomer et al (1999)

L08 Discuss two effects of the environment on physiological processes

What were the two

environmental effects we

used??

1. Environmental effects on brain plasticity

2. Environmental stressors and physiological processes

L08: Discuss two effects of the environment on physiological processes

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.

L08: Discuss two effects of the environment on physiological processes 1. Environmental effects on brain plasticity

Rosenzweig & Bennett (1972) 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.



Evaluation of Rosenzweig & Bennett (1972)

Rigorously controlled laboratory= possible to establish a cause-effect relationship.

Research challenged the belief that brain weight cannot change= important finding.

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?



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



Curtis (1977) Case study of Genie 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



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???

Evaluation of Genie Case Study



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


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



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.



http://ptsd.about.com/od/treatment/a/medsPTSD.htm

Kiecolt-Galser et al (1984) Exam Stress and Immune SystemAim: 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. LonelinessResults 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.



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)

Evaluation of Kiecolt-Galser et al (1984)



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)

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 amnesiaAmnesia 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


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


relevant studies.

LO9: Examine one interaction between cognition and physiology in terms of behaviour. Evaluate two relevant

studies.

H.M Case study evaluation

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


relevant studies.


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.

LO9: Examine one interaction between cognition and physiology in terms of behaviour. Evaluate two relevant studies.

Conclusions?

LO10: Discuss the use of brain imaging technologies in investigating the

relationship between biological factors and behaviour.

Can you name two

brain imaging

technologies?

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. Electroencephalogram (EEG)2. Positron Emission Topography (PET)3. Magnetic Resonance Imaging (MRI)4. 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

Electroencephalogram (EEG)



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

Positron Emission Topography (PET)



Uses magnetic field and radio waves to create detailed images of body.

Gives detailed pictures of internal structures in brain

Magnetic Resonance Imaging (MRI)

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

Ashtari et al (2009): MRI & marijuana

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.

Where have we already seen use of MRI?



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

Evaluation of Magnetic Resonance Imaging



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

Functional Magnetic Resonance Imaging (fMRI)

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

Harris and Fiske (2006): fMRI and prejudice



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

Where have we seen fMRI before?



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

Evaluation of Functional Magnetic Resonance Imaging



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).

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 were-

suggests 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.



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

Bouchard et al. concluded a heritability estimate of 70% - 70% of intelligence can be attributed to genetic inheritance. 30% attributed to other factors.



Same person 87%

MZA 86%

MZT 76%

DZT 55%

Siblings reared together

47%

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.

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.




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.


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 disgust- Fessler (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...

session 22 module revision. general learning outcomes lo1: outline principles that define the...

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