Research Methods Flashcards
Why do we describe questionnaires as a ‘method of self report’
questionnaires are where a participant answers questions about themselves and their opinions.
Why do we describe questionnaires as a ‘non-experimental’
you do not need an IV or DV (but you can have them). You are collecting opinions and answers from participants about a particular topic
True or false: Questionnaires can only be used on their own and not alongside other methods, for example, an experiment may use a questionnaire as a method.
False - Questionnaires can be used alongside other methods, for example, an experiment may use a questionnaire as a method.
True or false -Questionnaires can be given to a large amount of people which are referred to as a survey.
True
What are the two types of question which can be asked on a questionnaire?
Open and closed
What are open questions?
Participants are free to give any response. Allows participants to expand on their view points – written or verbal. Participants are asked to expand on their answers e.g., Explain how? Explain why? Collects qualitative data.
What are closed questions?
Participants are given a forced choice answer of a limited number of responses (participants must choose one).
Closed questions collect quantitative data.
Give an example of an open question from social psychology.
An example: “Explain a time that you disobeyed an order.”
Give an example of an open question from cognitive psychology.
What cues do you have that trigger some episodic memories such as holidays?
Give an example of an open question from biological psychology.
Why you would engage in a physical confrontation if you were angry instead of walking away?
Give an example of an open question from learning psychology.
Why your mum is your role model?
Give an example of an open question from child psychology.
How is your relationship with your mother?
Give an example of an open question from clinical psychology.
e.g. depression
How are your depression symptoms affecting your everyday life?
Give an example of a closed question in social psychology
I would obey my parents if they told me to stay in the house.
Strongly Agree 1
Agree 2
Not sure 3 Disagree 4
Strongly Disagree 5
Give an example of a closed question in cognitive psychology
Do you consider yourself to have a good memory? Yes No
Give an example of a closed question in biological psychology
On a scale of 1-5 how much do you agree with the following statement:
‘I lose my temper easily’
1=strongly agree, 5=strongly disagree
1 2 3 4 5
Give an example of a closed question in learning psychology
Is your mum your role model? Yes No
Give an example of a closed question in child psychology
Did you have a good childhood? Yes No
Give an example of a closed question in clinical psychology
Rank the following methods of talking therapy which you would find most suitable to help you (1=least effective to 4= lmost effective)
* Talking face to face
* Talking on the telephone
* Text messaging
* Other (e.g., instant messenger, direct messages on Instagram)
What is a Likert scale?
A type of closed questions where participants have to answer by indicating a number which reflects what they think
e.g. 1=strongly agree
2= agree
3=neither agree nor disagree
4 = disagree
5 = strongly disagree
Give a strength of a questionnaire
One strength of a questionnaire is that a large number of questionnaires can be administered quickly. This is a strength as it is cost efficient and less time consuming.
Give a strength of a questionnaire
One strength of a questionnaire is that they can be used to reach a wide range of participants. This is a strength as the results can be generalised to the target population.
Give a strength of a questionnaire
One strength of a questionnaire is that results can be completed privately and made anonymous. This is a strength as it means that participants are likely to give an honest, more valid response, reducing both social desirability and demand characteristics.
Give a strength of open questions
The use of open questions in a questionnaire increases validity. Participants will provide responses in a way they wish to and can go into lots of details to provide rich detail.
Give a strength of closed questions?
The use of closed questions can make the results easier to compare.
Give a weakness of questionnaires
One weakness of questionnaires is that participants may be influenced by social desirability. This is a weakness as participants may lie to provide answers which may look good, which lowers the validity.
Give a weakness of questionnaires
One weakness of questionnaires is that they often have low response rates. This is a weakness as it makes the results harder to generalise to the target population.
Give a weakness of questionnaires
One weakness of questionnaires is that they may have response bias. This is a weakness as only certain types of people may return the questionnaires, making the results less generalisable to the target population.
Give a weakness of closed questions
One weakness of questionnaires is that the use of closed questions and the element of forced choice may make responses less valid. This is a weakness as the responses may not accurately reflect a participants view point.
Give a weakness of closed questions
One weakness of questionnaires is that the use of closed questions means that participants may interpret the forced choices differently. This is a weakness as it will lower the validity of responses.
Give a weakness of open questions
One weakness of questionnaires is that the use of open questions may lead to issues of interpretation (subjectivity). This is a weakness as it will make the results harder to compare.
Why are interviews described as a method of ‘self report’?
Interviews are a method of self-report where someone answers questions about themselves or their opinions.
True or false - Interviews are non-experimental methods?
True - Interviews are a non-experimental method, where you do not need an IV or DV (but you can have them).
True or false - Interviews
can be used along side other experimental methods?
True - Interviews can be used alongside other methods, for example, an experiment may use a interviews as a method.
What are the three types of interview?
Structured, semi-structured or unstructured
What are structured interviews?
Everyone has set questions that are in a set order. The questions can not be changed, altered or expanded on.
What are semi-structured interviews?
A mid-way point between structured and unstructured. There are some set questions, but these can be followed up by adding questions if the participant discloses something of interest.
What are unstructured interviews?
There are no real set questions, just a general topic area to be studied. Questions can be changed and altered as needed. They are flexible, for example, someone might say something interesting, so you change the next question in line with this.
Give 2 strengths of interviews as a whole
- closed questions (e.g., yes or no) can be used o provide quantitative data meaning that the results can be easily analysed using a statistical test.
-open questions can be used to gather qualitative data which is rich in detail. This is a strength as due to the participant providing detailed responses, the results will be more valid.
Give 3 strengths of structured interviews
- Every participant receives the same questions, which is standardised. This is a strength as it means the results from the interview can be repeated and tested for reliability.
- This is also a strength as it means that the results are easy to compare.
- easy to conduct and do not require a lot of training. This is a strength as it means they are less time consuming.
Give a strength of an unstructured interview
- you can change the questions and add follow up questions if the participants states something interesting. This is a strength as participants will provide more detailed responses, therefore results will be more valid.
Give 4 weaknesses of interviews as a whole
- they can be time consuming. This is a weakness as it may be harder to repeat.
- people have to be trained to administer the interview. This is a weakness as it may be more costly and time consuming.
- the use of open questions leads to qualitative data, which may be subject to interpretation bias. This is a weakness as it means the results will be harder to analyse.
- answers given by participants can be influenced by social desirability. This is a weakness as the results of the interview may be less valid.
Give a weakness of a structured interview
One weakness of structured interviews is that you cannot change the questions to follow up on an interesting point. This is a weakness as the results will be less in-depth and therefore less valid.
What is a covert observation?
The participants do not know that they are being observed e.g. in public, through a one way mirror
What is an overt observation?
The participants know that they are being observed e.g. in a job interview
What is an naturalistic observation?
Where an observation takes place in a real life setting e.g. observing children sharing behaviour in a play room at nursery
What is a structured observation?
Where the environment has been created for the purpose of the observation e.g. Milgram
The researcher will control some of the variables thus reducing the naturalness of the behaviour.
* Often they take place in an artificial setting, such as a playroom for children.
What is a participant observation?
Where the observer is a part of the participants which they are observing
What is a non-participant observation?
Where the observer is not a part of the participants which they are observing e.g. behind a one way mirror
What is a coding system in observations?
A method of recording the behaviour which is observed
What is event sampling?
Event sampling: Use a coding scheme to tally events when they occur e.g. in Bandura the researcher recorded each time they heard the child say ‘sock em in the nose’ (imitated verbal aggression)
What is continuous sampling?
Continuous sampling: Making notes of everything which is happening.
What is time sampling?
Time sampling: Recoding their behaviours every nth time, for example every 30s or once every 3 minutes over a set period of time – you write down exactly what they’re doing at that moment.
Give 2 strengths of a covert observation
- there is less chance of demand characteristics, as participants do not know they are being observed making the findings more valid.
- there is less chance of social desirability as the participants do not know they are being observed making the findings more valid.
What is a weakness of covert observations?
One weakness of covert observations is that there are potential ethical issues as the participants do not know they are being observed. This is a weakness as there is no consent from the participant.
Give one strength of overt observations
One strength of overt observations is that there are less ethical issues as participants know that they are being observed.
Give 2 weaknesses of overt observations
-there is a high chance of demand characteristics which lowers the validity as the participant may try to behave in line with what they think the observer wants to see.
- there is a high chance of social desirability which lowers the validity as the participants may try to behave in a way that they believe is socially acceptable.
Give a strength of a participant observation
One strength of a participant observation is that it gathers in-depth information. This is a strength of a participant observation as the findings will be more valid.
Give 3 weaknesses of participant observations
- they may be difficult to replicate and so we cannot test the findings for reliability.
- the findings may have researcher/observer which bias is a weakness as the findings from the participant observation may not be valid.
- there is a high chance of demand characteristics which lowers the validity as the participant may try to behave in line with what they think the observer wants to see.
Give one strength of a non-participant observation
One strength of non-participant observation is that they may be less bias. This is a strength as the observer can view the situations objectively.
Give two weaknesses of non-participant observations
- there may be demand characteristics as the observer may influence the behaviour meaning that the behaviour observed is less valid.
- they gather less detail. This is a weakness as the findings may lack validity.
Give 3 strengths of structured observations
- the variables can be controlled meaning that there is less chance of extraneous variables, increasing validity of findings.
- they are often standardised so the findings can be tested for reliability.
-they are less time consuming. This is a strength is as we are ‘causing’ the situation, meaning it will be less time consuming as we would know the behaviours to look out for.
Give 3 weaknesses of structured observations
- they are often in lower in ecological validity meaning the findings will be less valid.
- they may be high in demand characteristics as the person knows they are being observed and may change their behaviour, reducing validity of the findings.
- there may be ethical concerns. This is a weakness as the observer is responsible for what is happening in the observation.
Give 2 strengths of a naturalistic observation
- they are high in ecological validity meaning that the findings can be applied to real life situations.
-there is a reduction in demand characteristics meaning the findings from a naturalistic observation will be more valid.
Give 3 weaknesses of a naturalistic observation
- they do not follow a standardised procedure so we can not test the findings for reliability.
- One weakness of a naturalistic observation is that you can not only EV’s. This is a weakness as the findings are less valid.
- One weakness of a naturalistic observation is that they are more time consuming. This is a weakness as you are waiting for a behaviour to occur naturally.
What ‘big question’ do adoption studies attempt to answer about a mental health condition?
If it is ‘nature’ or ‘nurture’
How is an adoption study carried out?
We find an adopted person with a specific trait and we look at how many of their biological family members (usually parents) and adopted family members also share that trait (and compare those two concordances).
*They look at differences in frequency between groups and may also compare these levels with the baseline level in the population.
What is measured in an adoption study?
- Researchers look at the frequency with which a trait occurs in children living with a parent who has that same trait.
- They also look at rates for children of people with that trait who have been adopted into families without that trait.
What is our adoption study in biological psychology?
Kety
What was the aim of Kety?
Aim: To find out if there is a genetic basis for schizophrenia and to see if there is a higher rate of
schizophrenia-related illness among biological relatives than adoptive relatives.
What is the sample of Kety?
34 schizophrenic patients (two of them MZ twins) taken from the Danish Adoption Register for
Copenhagen. They were aged 20-43. These are referred to as ‘index patients’
Control: 33 mentally-healthy Controls were selected from the Danish Adoption Registry. They were
matched to the schizophrenic patients on age, gender, the age at which they were adopted and the social
class of the adoptive family.
What groups were the index patients split into in Kety?
- B1 was a group of 16 patients with chronic (long-term) schizophrenia
- B2 was a group of 7 with acute (short-term or one-off) schizophrenia
- B3 was a group of 11 with “borderline schizophrenia” or “latent schizophrenia”
What was the independent and dependent variables in Kety?
IV: Schizophrenia sufferers and a Control Group with no history of mental illness.
DV: The researcher’s measured the prevalence of schizophrenia-related mental illness among family
members
What is the method of Kety (your adoption study)?
-Danish family records were used to locate adoptive and biological relatives of all the participants (463 relatives used and their mental health status was assessed).
- Using a blind test (the psychiatrists did not know whether the records were from an adoptive or a biological family member) 4 Danish psychiatrists used the medical records to diagnose the family members
-4 Psychiatrists diagnosed the family based on their medical records and classified them as SZ or no and they were then assigned to either ‘adoptive’ or ‘biological’ relative groups once identities were revealed
- In 4 cases, they couldn’t reach a conclusion and these relatives were dropped from the study
Give 2 results of Kety
Of 150 biological relatives of index cases;
* 13 (8.7%) had a diagnosis of schizophrenia (or similar)
* Of 156 biological relatives of the controls;
* 3 (1.9%) had a diagnosis of schizophrenia (or similar)
What is the conclusion of Kety?
There seems to be a genetic component to schizophrenia. Schizophrenic adoptees were more
likely to have schizophrenia in their biological family than their adoptive family. Their biological families
were more likely to have schizophrenia than the families of Controls
Is it a strength or a weakness that adoption studies help us to determine if behaviour is due to nature or nurture and why?
Strength. This is a strength of adoption studies as it is useful in helping us determining why a behaviour may occur in order for us to put support/interventions into place to support a person.
Is it a strength or a weakness that adoption studies are naturally occurring and they do not require manipulation of groups from the researcher.
Strength
One strength of adoption studies is that they are considered ethical. This is a strength as adoption is a naturally occurring events that does not require manipulation of groups from the researcher.
Why is it a weakness that adopted children need to be identified, followed for a long time and locate and assess each of the family members?
One weakness of adoption studies is that recruitment may take a long time to find children who meet the criteria and match to families. This is a weakness as it becomes time consuming as it may take several years.
Why can it be difficult to establish ‘nature vs nurture’ in an adoption study?
One weakness of adoption studies is that it may be difficult to establish what is due to nature or nurture. This is a weakness as the prenatal environment of the children may be different.
Why is it a weakness for validity in adoption studies that some children are adopted by people who are the same culture as their biological parents?
One weakness of adoption studies is that it may be difficult to establish what is due to nature or nurture. This is a weakness as adopted children may be adopted by a family culturally similar to their biological one and so may end up with some shared environment.
Why is attrition an issue for adoption studies?
One weakness of adoption studies is that there may be attrition (participant drop out). This is a weakness as the results in the adoption studies may not longer be representative.
Content analysis is used to turn _________ data into ____________ data
Qualitative –> Quantitative
What type of data can content analysis analyse?
Qualitative
What are the steps to content analysis?
- Read through the data (familiarisation)
- Identify themes/key words which arise (exactly the same as thematic analysis)
- count up how many times those themes occur.
- Summative content analysis - you look at themes about when and where those themes occur (who said them in different instances).
- Produce final report
What type of things could you conduct a content analysis on?
Newspaper articles, interviews, books, open question answers on questionnaires
Give 3 strengths of content analysis
- Content analysis produces quantitative data which you can then analyse statistically so you can establish if the results are due to chance
- The process is standardised so it can be re done to test for reliability.
- Multiple researchers can do it to test for inter rated reliability
- Ethical as it uses secondary data
Give 3 weaknesses of content analysis
- Can be subjective as the researcher is selecting themes and there could be bias which reduces validity
- The findings may lack internal validity owing to this subjectiveness
- One weakness of content analysis is that it reduces complex information down to a simpler form. This is a weakness as important information may be loss and therefore may reduce the validity.
What are the 3 ‘research designs’
-Independent measures
-Repeated measures
-Matched pairs
What is independent measures?
Participants only take part in one condition of the experiment (requiring two separate groups).
How does independent measures design avoid order effects to increase validity?
One strength of independent measures is that it avoids order effects. This is a strength as the participant will not become bored or tired in the experiment therefore increasing validity.
Why do we reduce demand characteristics when using independent measures design?
One strength of independent measures is that there is less chance of demand characteristics. The participant is less likely to know the aims as they only do one condition, thus increasing the validity.
Give one weakness of independent measures design
One weakness of independent measures is that more people are needed due to separate conditions in comparison to a repeated measures design. This is a weakness as it will be more time consuming to conduct.
Give one weakness of independent measures design
One weakness of independent measures design is that there are participant variables. This is a weakness as the differences between the groups may affect the results, for example variations in age, sex or social background.
Give the AO1 for repeated measures
One group of participants take part in both conditions of the experiment.
Why is it a strength that participant variables are reduced in repeated measures?
One strength of repeated measures design is that it avoids participant variables, as compare scores from one condition to another for the same participant. This is a strength as it increases validity of the results.
Is it a strength or a weakness that in a repeated measures design less people are needed?
Why is this a strength/weakness?
One strength of repeated measures design is that fewer people are needed, as the same people can take part in group conditions. This is a strength as it is less time consuming.
Give one weakness of repeated measures
- One weakness of repeated measures is that demand characteristics are more likely as participants are involved in all conditions. This is a weakness as validity is reduced.
Give one weakness of repeated measures
One weakness of repeated measures is that order effects are more likely to occur. This is a weakness as it reduces validity.
How can we reduce the risk of order effects when using repeated measures?
Counter balancing
What is counter balancing and how does it reduce order effects?
Alternating the order in which participants perform in different conditions of an experiment. For example, group 1 does A then B, group 2 does B then A to eliminate order effects.
What is matched pairs? Give some examples of what people can be matched on.
Participants are matched in each condition for characteristics that may have an effect on their performance, e.g., IQ, age, previous test scores.
Give 3 strengths of using a matched pairs design
- matched pairs design is that it avoids participant variables, as compare scores from one condition to another for the same participant which increases the validity of the results.
- matched pairs design avoids order effects so the participant will not become bored or tired in the experiment therefore increasing validity.
- Using matched pairs design is that there is less chance of demand characteristics as the participant is less likely to know the aims as they only do one condition, thus increasing the validity.
Give 2 weaknesses of a matched pair design
- matched pairs design means that it may be hard to find appropriate matches for all participants which is a weakness as it may be very time consuming to do and there may still be participant variables.
- One weakness of matched pairs design is that it requires more participants. This is a weakness as it will be very time consuming to recruit.
Which classic studies have you looked at in paper 1 which used a matched pair design in their design. What were the participant’s matched on?
Sherif (boys matched on IQ and sporting ability)
Raine (matched on age, education and family history of mental illness)
Which classic studies have you looked at in paper 1 which used an independent measures design in their design.
Baddeley - p’s only completed 1 of the 4 word lists
Define qualitative data
Data in non-numerical form (words)
Define quantitative data
Data in numerical form (numbers)
Give one strength of qualitative data
Example:
- Rich detailed data that explains a behaviour
Give one weakness of qualitative data
Example:
- Subject to interpretation bias where the reader puts their own opinion onto the data, meaning it may not be an accurate measure
Give one strength of quantitative data
Example: easy to statistically analyse to determine significance which means we can draw accurate conclusions
Give one weakness of quantitative
Example:
Lacks depth and detail, meaning we don’t understand why a participant answered/behaved that way
List the 6 steps to complete a thematic analysis
- familiarise with data
- identify initial codes
- group codes into themes
- review themes
- name and define themes
- produce a report
Thematic analysis is a method to analyse what type of data?
Qualitative
What is the key difference between a thematic analysis and a content analysis?
Thematic provides qualitative data, content provides quantitative data
Give one strength of thematic analysis
Example:
Uses qualitative data which is rich and detailed meaning we can get an understanding of the data, so more accurate conclusionsg
Give one weakness of thematic analysis
Example:
Subject to researcher bias where the views and opinions of the researcher might impact the codes/themes, meaning the results are not accurate
opportunity sampling uses participants who are __________________
Available at the time
In stratified sampling, the target population is split up into …. to understand the proportions
Stratas - e.g. male and female
In which sampling technique do participants offer to be part of the research?
Volunteer
Which of the sampling techniques is the fairest and why?
Random sampling - everyone in the population has an equal chance of being picked
Define stratified sampling
When the population is split into specific groups/strata based and a representative proportion is selected from each strata
Give one weakness of volunteer sampling
Example:
might have shared characteristics as only helpful people may volunteer meaning it can’t be generalised to non-helpful people
which sampling technique might put all names into a hat and pick them out?
random
which sampling technique has issues with shared characteristics?
Volunteer and opportunity
Give one strength of stratified sampling
e.g. includes a representation of the population so more generalisable
give one weakness of opportunity sampling
e.g. only represents people available at the time
What stats test do we use for a correlation?
Spearmans Rho
What do we call the number that represents the strength and direction of a correlation?
Correlation co-efficient
A correlation can be between what two numbers?
-1 and 1
Can a correlation identify a cause and effect relationship and why?
No - it just shows the relationship as there is no manipulation of the variables
What do we call the variables in a correlation?
co-variables
what type of graph shows a correlation?
scatter graph
Give two strengths of correlations
Examples:
- no manipulation so more ethical
- quantitative data so easy to statistically analyse
Give two weaknesses of correlations
Examples:
- quantitative data lacks depth and detail
- can’t get a cause and effect relationship so don’t know if one variable impacts the other - less valid
Likert scale questions are an example of…
ordinal data
putting participants into groups of ‘old’ and ‘young’ is an example of…
nominal data
Time in seconds is an example of…
interval data
Define nominal data
data in discrete categories
Define interval data
data that increases in set increments that are universal
which stats test would we use if we had nominal data?
chi squared
Define ordinal data
data that is not in set increments or not universal but can be ranked
For a Mann Whitney U, which level of measurement do we need?
at least ordinal
For a Spearmans Rho, which level of measurement do we need?
At least ordinal
For a Wilcoxon, which level of measurement do we need?
At least ordinal
What are the key parts of the Animals Scientific Procedures Act 1986?
- procedures should not cause pain and discomfort
- choose a species least likely to suffer
- keep number of animals to a minimum
- keep them in a setting as close to their natural habitat as possible
Researchers must obtain a licence and certificate from who?
Home Office
Who should give anaesthetics?
a qualified person
what tool do researchers use to decide if a piece of animal research is justified?
Batesons Cube
What factors does a Bateson’s cube analysis take into account?
Cost to animal and benefit to society
Give 1 practical strength of animal research
e.g.
Conducted in a lab, so easily standardised
Controlled environment to ensure no extraneous variables
Give 1 practical weakness of animal research
e.g.
Animals have different anatomy to humans so can not generalise
Give 1 ethical strength of animal research
Researchers need a licence from the home office and need to pass an ethics test to get it
Give 1 ethical weakness of animal research
Research is done in a lab which can be distressing and harmful to the animals
Where do lab experiments take place?
An artificial setting
Give 3 facts about a lab experiment
Have variables which researchers manipulate to determine cause and effect
High level of control to eliminate extraneous variables
Follow a standardised procedure
Typically collect quantitative data
Why is it a strength that a lab experiment is highly controlled?
Eliminates extraneous variables which increases validity of the experiment as we can be more sure that the IV did affect the DV (cause and effect)
Lab experiments are standardised. Why is this a strength?
Each participant will do the exact same procedure meaning results can be compared = more reliable
What is a weakness of a lab experiment in terms of validity?
Low ecological validity as it takes place in an artificial setting = not reflective of real life
High in demand characteristics as Ps may guess the aim of the study = less reflective of behaviour in real life
Where does a field experiment take place?
A naturalistic setting e.g. classroom, public transport
Give 3 facts about a field experiment
Researcher has control over the IV to see if it affects the DV
Lower levels of control as it takes place in the real world
Procedure is not standardised
What is a strength of a field experiment in terms of validity?
High ecological validity due to taking place in a naturalistic setting = more representative of behaviour in real life
Less demand characteristics as P less aware of the study = more representative of real life behaviour
What is a weakness of a field experiment in terms of validity?
harder to control extraneous variables = less sure that the IV did affect the DV
What is a weakness of a field experiment in terms of reliability?
not standardised - they can not be replicated to test for reliability.
What is a hypothesis?
A prediction about the outcomes of a study
What is a one tailed / directional hypothesis?
A prediction that includes the direction of results (says who will do better)
What is a two tailed / non directional hypothesis?
A prediction that says there is a difference/relationship, but does not state the direction
What is a null hypothesis?
A prediction that states there is no difference between the two groups / no relationship between the variables
What is operationalisation?
Stating exactly how the variables will be measured in a hypothesis
What is the independent variable?
The variable that is manipulated
What is a dependent variable?
The variable that is measured
What is a cause and effect relationship?
The independent variable is the cause of the changes seen in the dependent variable
What is an extraneous variable?
A variable other than the independent that is not controlled for that may affect the results seen in the dependent variable
What is a participant variable?
Something about the individual participant that may affect the results e.g. age, IQ, mental health, personality type
What is a situational variable?
Something about the research situation that may affect the results e.g. noise level, environment
What is a confounding variable?
A variable that is not the IV, that changes consistently with the IV and impacts the DV – e.g. doing a test to see the impact of energy drink on memory, but the energy drink group are 20 years old, and the non energy drink group are 90 – so their age will also impact memory
How can extraneous variables be controlled?
Standardised procedure
Artificial setting
How does a PET scan work?
- A radioactive chemical dye is injected into the blood of a person (irradiate glucose).
- As the chemical breaks down it releases radioactivity which can be picked up on the scan.
- The more active the brain for a specific task the more radioactivity that will be picked up by the scan.
- The scan creates a colourful image. Darker/warmer (red/orange) areas show more activity and lighter/cooler (blue/green) areas show less activity.
What does a PET scan show?
Activity of the brain - which areas are using more glucose (energy)
Give two strengths of a PET scan
Process is standardised
Objective measure of brain activity
Give two weaknesses of a PET scan
Lacks ecological validity as it takes place in an artificial setting
Invasive as requires participant to be injected with a radioactive tracer
How does an fMRI scan work?
- The person lies in a large cylinder in which they must lie perfectly still.
- Magnet and radio waves are then sent through the body.
- As neural activity increases in the brain, blood flow increases in active areas and requires more oxygen.
- Oxygen is carried to the areas via haemoglobin in red blood cells.
- Haemoglobin when it is full of oxygen repels the magnetic field (diamagnetic) but follows the field when it is deoxygenated (paramagnetic) and it uses these changes to build up an image.
Give two strengths of an fMRI scan
Process is standardised so can be repeated
Objective measure of brain activity
Give two weaknesses of an fMRI scan
Lacks ecological validity
Can be claustrophobic so some may not want to take part
Not accessible for everyone e.g. those with pacemakers cannot take part
How does a CAT scan work?
- CAT scans involve a focused X-Ray beam being beamed into the brain.
- This is done at many angles which can then be put together into a full picture.
What does a CAT scan show?
The structure of the brain
Give two strengths of a CAT scan
Process is standardised
Objective measure of brain activity
Give two weaknesses of a CAT scan
May be considered invasive due to frequent exposure to radiation
Lacks ecological validity
What is an MZ twin?
Identical twin, share 100% DNA
What is a DZ twin?
Non-identical twin, share 50% DNA
What does a twin study allow us to investigate?
Whether the cause of a behaviour or trait is nature (genetic) or nurture (environmental)
What is concordance?
The extent to which both twins share the same characteristic e.g. if twin 1 has Schizophrenia, what percentage of the time does twin 2 also have Schizophrenia
How is a twin study carried out?
Find a set of twins where at least one of them has the specific trait or characteristic being studied
Use a variety of strategies to ensure the allocation to MZ or DZ is accurate (e.g., DNA testing).
Measure the concordance rate in the other twin (how often the second twin also has the trait)
What is a strength of twin studies in terms of usefulness?
They help us determine whether a behaviour is due to nature or nature - useful in helping us determining why a behaviour may occur.
What is a strength of twin studies in terms of validity?
Can use DNA testing to determine if the twin is MZ or DZ
Often use triangulation of data to measure a specific trait
What is a weakness of twin studies in terms of generalisability?
Twins are relatively rare in the population. This is a weakness as the results from the twins may not be generalisable to the wider population.
What is a weakness of twin studies in terms of validity?
It is often assumed that the difference between MZ and DZ twins is the amount of DNA, but MZ twins are often treated more similarly than DZ - differences may be environmental not genetic
What is an example of a twin study in Psychology?
Brendgen
How do adoption studies work?
Find an adopted parent/adopted child with a specific trait
Look at how many biological family members and adopted family members also have that trait
Compare the concordance rates between biological family members and adopted family members
What does an adoption study show?
Whether a behaviour is genetic (higher concordance with biological family) or environmental (higher concordance with adopted family)
What is an example of an adoption study in Psychology?
Kety
What is a strength of an adoption study in terms of usefulness?
They help us determine whether a behaviour is due to nature or nature - it is useful in helping us determining why a behaviour may occur.
What is an ethical strength of an adoption study?
Adoption is a naturally occurring event that does not require manipulation of groups from the researcher - don’t need to worry about protection from harm etc
What is a weakness of adoption studies in terms of validity?
It may be difficult to establish what is due to nature or nurture - the prenatal environment of the children may be different.
Adopted children may be adopted by a family culturally similar to their biological one and so may end up with some shared environment.
What is a weakness of adoption studies in terms of generalisability?
There may be attrition (participant drop out). This is a weakness as the results in the adoption studies may not longer be representative.
What is primary data?
Information collected first hand by the researchers e.g. interview the researcher conducts themselves
What is a strength of primary data in terms of validity?
Data is used for intended purpose so more likely to be relevant
Can be qualitative and quantitative
What is a strength of primary data in terms of ethics?
Researcher(s) are in contact with their participants and can be sensitive to any issues that arise, such as distress of a participant
What is a weakness of primary data in terms of generalisability?
Primary data sets are often quite small so may be harder to draw conclusions compared to meta-analysis of secondary sources
What is a weakness of primary data in terms of ethics?
Primary data collection is more likely to exploit potential participants than secondary
What is a weakness of primary data in terms of validity?
There may be a danger of personal bias on the part of the researcher which could affect the data collection
What is secondary data?
Data that has already been gathered / already exists e.g. previously published academic work
What is a practical strength of secondary data?
Quicker than primary data
Less expensive as costs involved in producing research do not have to be incurred
What is a weakness of secondary data in terms of validity?
Data may have been collected some time ago so responses may have changed as views in society are constantly changing - low temporal validity
What is a meta-analysis?
Statistical analysis that combines the results of multiple scientific studies - doing statistics on data that already exists.
Is a meta-analysis primary or secondary data?
Secondary data
How is a meta-analysis carried out?
Collect a sample of existing research in a set topic
Analyse the data from all studies together to get a larger overview of statistical significance of the results
What is a strength of a meta-analysis in terms of generalisability?
Uses secondary data so a large sample can be gathered = more representative of the wider population
What is a strength of a meta-analysis in terms of validity?
Allows for further analysis to be conducted so more valid conclusions can be drawn from the data
What is a practical strength of a meta-analysis?
Quicker to conduct as it involves secondary data
Less expensive as you do not have to conduct the study yourself
What is a weakness of a meta-analysis in terms of validity?
Data may have been collected a while ago so no longer relevant to today
Researcher bias when choosing studies to include in the sample
Publication bias - non-significant findings are not published so findings from the meta-analysis may be skewed
How is a meta-analysis different to a review of studies?
Meta-analysis requires the researcher to statistically analyse the results from the existing data, review of studies does not
