all classic & contemporary studies Flashcards
SOCIAL PSYCHOLOGY
classic study (AO1)
AIM: To find out what factors make two groups develop hostile relationships and to see how this hostility can be reduced. Specifically, to see if two groups of boys can be manipulated into conflict through competition and then conflict resolution by working together.
SAMPLE: 24 PP’s (11-year-old boys) who were selected by opportunity sampling and did not know each other before the study. They were matched as far as possible and split into 2 groups. They were all from Protestant families in Oklahoma and were screened to eliminate problems at home and other difficulties that might account for individual attitudes and behaviour (individual differences). The boys were unaware that they were involved in a study and the parents were told not to visit in case the boys got homesick.
SETTING: The camp was a 200-acre Boy Scouts of America camp, completely surrounded by Robbers Cave State park. The site was isolated, keeping both groups away from each other and reducing the risk of extraneous variables influencing their behaviour.
IV: The IV is the stage of the experiment: (1) in-group formation, (2) friction phase and (3) integration phase.
DV: Intergroup behaviour was measured by observing the boys behaviour and friendship patterns and tape recording their conversations and recording the phrases they used. The boys also filled out questionnaires on their attitudes towards their own group and the other group.
DESIGN: repeated measures design.
PROCEDURE:
(stage 1) in-group formation
The two groups were kept separate and away from each other in cabins on two sites. They were unaware of the other group, thinking they were alone at the park. Each group had junior camp counsellors (college students earning money during the summer) who lived with the boys and supervised their activities and the senior camp counsellors were participant observers who stayed with the boys for 12 hours a day. Sherif was very clear that he did not want the observers to influence the boys in any way.
In-group formation lasted a week and each group had tasks to accomplish (e.g. a treasure hunt with a $10 prize). During this time, 2 boys went home because they were homesick which left 11 in one group and 9 in the other group.
data collection:
data was collected by observation, including rating of emerging relationships, sociometric measures and experimental judgements.
- observation: a PP observer was allocated to each group for 12 hours a day.
sociometric analysis: issues such as friendship patterns were noted and studied.
- experiment: (e.g. the boys had to collect beans and estimate how many each other collected).
- tape recordings: adjectives and phrases used to refer to their own group members and to out-group members were examined.
(stage 2) the friction phase
After the first week, the two groups were told about one another and a tournament was set up with competitive activities. This involved sports like baseball, tug-of-war and a scavenger hunt but also experimental tests like a bean-counting competition. As soon as the groups heard about each other they became hostile and wanted to play each other at baseball, so they effectively set up their own tournament (which was what the researchers wanted).
The aim behind the competition was to make one group frustrated because of the other group, to see if negative attitudes developed. Adjectives and phrases were recorded to see if they were derogatory towards each other.
(stage 3) integration phase
In the integration phase, Sherif and the other researchers wanted to bring the two groups together to achieve harmony. They tried ‘mere contact’ by allowing the groups to have dinners and watch films together in the recreation hall. When this failed, they took a different approach, blocking the water pipe to the camp which forced boys to walk together to find the broken portion of the pipe. Other tasks included choosing films to watch together and cooperating to pull a broken-down truck.
RESULTS:
(stage 1) in-group formation
Near the end of stage 1, the boys gave themselves names: the Rattlers and the Eagles. The Rattlers discussed the other group frequently, like them saying ‘they better not be in our swimming hole’ or the Eagles becoming competitive and asking them to play a baseball game. This showed the very existence of out-groups led to hostility and competition.
(stage 2) friction phase
Once the two groups met for baseball, name-calling started immediately. The Eagles burned the Rattler’s flag and the Rattlers retaliated by doing the same.
After their second flag was destroyed, the Rattlers do a night raid on the Eagle’s cabins, stealing comics and overturning beds.
The Eagles launched their own raid, but brought bats with them for maximum destruction.
When the Eagles won the tournament, the Rattlers stole their prizes (medals and knives).
(stage 3) integration phase
In the integration phase, the shared films and meals deteriorated into name-called and food fights. The shared task of fixing the water pipe produced cooperation, but another food fight followed. However, each task led to reduced hostility. By the end, the Rattlers shared 5$ they had won to buy soft drinks for everyone.
CONCLUSIONS: Sherif regards the study as proving his hypothesis about intergroup behaviour especially Realistic Conflict Theory.
The groups formed quickly, with hierarchies and leaders without any prompting by the adults.
When the groups meet in competitive situations, in group solidarity increases as does outgroup hostility,
Friction is reduced when the two groups are forced to cooperate, negotiate and share. Sherif calls this working towards ‘superordinate goals’.
what is the classic study in social psychology?
Sherif et al. 1954/1961
Robbers Cave Experiment
SOCIAL PSYCHOLOGY
classic study (AO3)
(AO3) EVALUATION OF SHERIF ET AL. (1954/61)
generalisability
WEAKNESS: Sherif et al. used a sample of 22 boys, which is not a large sample. This means that there is a risk of anomalies skewing the results (e.g. boys with unusual characteristics like being violent bullies) however, Sherif did go to lengths to screen the boys beforehand, removing any troubled backgrounds or antisocial behaviour. Furthermore, the sample is androcentric and ethnocentric. He uses a sample of all boys who are all American. This is a problem because it does not represent mixed sex groups or other cultures, meaning that the results have limited generalisability to only the boys.
reliability
WEAKNESS: Since his study involves observation, there are issues with reliability in this study because the observers were only there for 12 hours of the day and could not see or over hear everything that went on. This means that possibly the data is not entirely reliable or accurate as there could be missing information.
STRENGTH: Despite this, Sherif took pains to make the study more reliable because he used a numbered scoring system for the boys’ friendship patterns, which collected quantitative data. He also used multiple observers on occasions, creating inter-rater reliability and recorded the boys’ conversations to be analysed later. Furthermore, the standardised procedure (e.g. the bean-counting test) could be replicated meaning that they could be tested to determine whether the results are reproducible.
application
STRENGTH: The study/theory has useful application value as it shows how competition and frustration creates hostility towards out-groups. This could be applied in society where discrimination and violence could be reduced if jobs, housing, education and other opportunities were shared more fairly between different groups such as ethnic groups or social classes. This is the basis for a lot of Left Wing thinking. This furthers the idea that working towards shared common goals (superordinate goals) can reduce prejudice and discrimination within communities.
validity
STRENGTHS: Sherif claimed that by using several different research methods (observing, tape records, quantitative and qualitative data and tests), he was making the study more valid. As well as this, the setting was natural and the study has ecological validity as real boys at a summer camp, unaware that they’re being observed. This is a strength because it addresses the issue of mundane realism and prevents demand characteristics or social desirability bias, ensuring that the research is objective and valid.
ethics
WEAKNESS: The boys did not give valid consent to be in this study and did not seem to be debriefed afterwards, they never realised they were being experimented on. This certain fails to respect their autonomy because they had no choice and their dignity as they were tricked and put through some upsetting conflicts. They were also deceived about the broken water pipe and the food truck breaking down. Furthermore, the hostility that manifested in vandalism or theft subjected the participants to risk as they nearly had a serious fight. However, the researchers did drop their professional detachment when a serious fight nearly broke out and intervened to prevent it, which is an example of scientific integrity.
STRENGTH: The boys did however, give presumptive consent because their parents were aware that this camp was some sort of psychology project. However, they were asked not to visit the camp and were not aware of all of the details. The boys could withdraw from the study as 2 of them went home in the first week.
what is the contemporary study in social psychology?
Burger 2009
Replication of Milgram’s Original Obedience Study
SOCIAL PSYCHOLOGY
contemporary study (AO1)
AIM: To find out if the same results as Milgram’s 1963 study into obedience re-occur when the study is replicated with modern participants in 2009 and with ethical implementation. Also to see if personality variables like empathy and locus of control influence obedience. Finally, to see if the presence of a disobedient ‘model’ makes a difference to obedience levels.
IV: The main IV is the base condition (same as Milgram, 1963) compared with the model refusal (rebellious partner) condition. This is an independent groups design as it compares the 2009 participants with the 1960s participants and compares the control group with the disobedient model group.
DV: Obedience is measured by how many volts the last shock to be delivered was, before the participant refused to continue or exhausted all the ‘prods’ or reached 150V (max. voltage).
SAMPLE: 70 PP’s (a mixture of men and women) did the experiment, being randomly assigned into the two conditions. They were a volunteer sample, recruited through newspaper and online ads and fliers left in libraries. They were paid $50 before the study started. They were aged 20-81.
Burger actually recruited a lot more PP’s but screened many of them out. He dropped volunteers who had: heard of Milgram’s original experiment, who had attended more than 2 Psychology classes, who had anxiety issues or drug dependency. It was a two-step screening process, those with psychological knowledge were screened before even attending and those with drug or emotional issues were screened through a questionnaire when they arrived.
PROCEDURE: The procedure replicates Milgram’s variation 5 on his baseline study. The experimenter is a white man in his 30s; the confederate (learner) is in his 50s. The script resembles Milgram’s but the test shock the PP receives is only 15V than Milgram’s painful 45V. The PP (teacher) watches the learner being strapped into the electric chair and then sits at the shock generator in the adjacent room.
The teacher reads out 25 multiple choice questions and the learner uses a buzzer to indicate the answer. If the answer is wrong, the experimenter then directs the teacher to deliver a shock, starting at 15V and going up in 15V intervals.
The learner indicates he has a ‘slight heart condition’ but the experimenter replies that the shocks are not harmful. At 75V the learner starts to make sounds of pain. At 150V the learner cries that he wants to stop and complains about the chest pains.
In the “model refusal” condition, a second confederate pretends to be a second teacher. This teacher delivers the shocks, with the naïve participant watching. At 90V the confederate teacher turns to the naïve participant and says “I don’t know about this.” He refuses to go on and the experimenter tells the naïve participant to take over delivering the shocks.
Burger used questionnaires to measure individual differences that might be factors in obedience: Interpersonal Reactivity Index, a 28-question test that measures empathy and how sensitive you are to other’s feelings; Desirability of Control Scale, a 20-question test that measures locus of control- how important it is for you to be in control of events in your life.
Burger also used ethical controls that improved Milgram’s 1963 procedure:
There was a two-step screening process to filter out anyone who might be unduly stressed by the experience.
The PP’s were warned 3 times in writing that they could withdraw at any point in time and keep the $50.
The experimenter was actually a clinical psychologist, skilled in spotting and reacting appropriately to distress.
The ‘test shock’ experienced by the PP’s was only a mild 15V, not Milgram’s painful 450V.
Burger did not allow time to pass before he introduced the healthy learner and debriefed the PP’s.
RESULTS: Burger found that 70% of the PP’s in the baseline condition were prepared to go past 150 V, compared to 82.5% in Milgram’s Variation 5.
Burger also compared men and women but did not find a difference in obedience. Women were slightly less likely to obey in the ‘model refusal’ condition but this was not statistically significant.
Empathy did not make a significant difference to obedience. However, in the base condition those who stopped at 150V or sooner did have a significantly higher locus of control.
CONCLUSIONS: Burger concludes that Milgram’s results still stand half a century later. People are still influenced by situational factors to obey an authority figure even if it goes against their moral values.
Burger assumes that any PP willing to go beyond 150V would have been willing to go all the way to 450V the way Milgram’s PP’s did. He argues that their ‘self-perception’ would have made them do this.
SOCIAL PSYCHOLOGY
contemporary study (AO3)
(AO3) EVALUATION OF BURGER 2009
generalisability
STRENGTH: Burger’s sample of 70 PP’s is larger than Milgram’s sample of 40. It covers a wider age range (Milgram recruited 20-50 year olds, Burger recruited 20-81 year olds) and ⅔ of Burger’s sample were women whereas Milgram’s were all male.
COUNTER-ARGUMENT: However, when you add up all of Milgram’s samples across all his variations, there are much more participants and Milgram did test women in Variation 8. Burger also excluded a lot of people from his final sample, for example people with emotional issues or some education in Psychology. This may have affected the representativity of the results as it discludes a lot of types of people.
reliability
STRENGTH: Milgram’s original procedure is very reliable because it can be replicated. In 1974, Milgram published the results of his 19 Variations, which all replicated his baseline 1963 study. Burger is replicating aspects of Variation #5 (heart condition to test for empathy) and Variation #17 (model refusal) as well as Variation #8 (testing women). Burger followed Milgram’s script wherever possible and used the same confederates every time. By filming the whole thing, Burger adds to the inter-rater reliability because other people can view his participants’ behaviour and judge obedience for themselves.
application
STRENGTH: The study demonstrates how obedience to authority works and this can be used to increase obedience in settings like schools, workplaces and prisons. Authority figures should wear symbols of authority (uniforms) and justify their authority with reference to a “greater good”. Testing people for locus of control might identify those most likely to be disobedient – people with a strong need to be in control are less likely to take orders. Social Impact Theory suggests strategies for increasing the pressure on these people to be obedient.
validity
WEAKNESS: Milgram’s study was criticised for lacking ecological validity because the task is artificial – in real life, teachers are not asked to deliver electric shocks to learners. This criticism still applies to Burger’s study. In other ways the study is valid. Because the participants were paid fully in advance, we can be fairly sure it was social pressure that made them continue shocking, not a cost/benefit calculation about whether they personally would gain or lose money. However, stopping the study at 150V may be invalid. Perhaps participants who were prepared to go to 165V would still have dropped out later. It is a huge assumption to say they would have continued to 450V. The “model refusal” group, in particular, might have had second thoughts as the shocks got stronger.
ethics
STRENGTH: Burger believes his study avoids the ethical problems of Milgram’s original. Burger screened out participants who were likely to be distressed by the study. The Experimenter was a trained clinical psychologist who could identify signs of distress and would stop the experiment if anyone seemed to be disturbed by what was happening. The study was approved by the university Ethics Panel, who had the power to shut it down if it looked like anyone was being harmed. Burger reduced the test shock from a painful 45V to a mild 15V. He also stopped the study at 150V so he didn’t force anyone to “go the distance” to 450V, which reduced many of Milgram’s participants to tears (and three of them fainted).
COUNTER-ARGUMENT: Nonetheless, there are still ethical criticisms. Burger deceived his participants just as Milgram had done – the shocks weren’t real, the learner’s cries were a tape recording, the learner and second teacher were confederates. He did not get informed consent(as with Milgram, this was advertised as a memory study), although he did debrief participants afterwards. The BPS Ethical Guidelines say participants must not be distressed; even though no one was reduced to tears, the procedure was surely distressing for at least some participants.
what is the classic study in cognitive psychology?
Baddeley 1966
Semantic Encoding in Long-Term Memory
COGNITIVE PSYCHOLOGY
classic study (AO1)
BADDELEY
Semantic Encoding in Long-Term Memory *WMM
AIM: To find out if LTM encodes acoustically (based on sound) or semantically (based on meaning). This was done by giving participants word lists that are similar in the way they sound (acoustic) or their meaning (semantic); if the PP’s struggle to recall world order, it suggests LTM is confused by the similarity which means that this is how LTM tends to encode.
IV: This is a lab experiment that has several IV’s. (1) acoustically similar word list or acoustically dissimilar word list (2) semantically similar word list or semantically dissimilar (3) performance before 15 minutes ‘forgetting’ delay and performance after.
IV’s (1) and (2) are tested using Independent Groups Design but IV (3) is tested through Repeated Measures.
DV: Score on a recall test of 10 words; words must be recalled in the correct order (really, this is a test of remembering word order, not the words themselves).
SAMPLE: Men and Women from the Cambridge University subject panel (mostly students) who were volunteers. There were 72 altogether, a mixture of men and women. There were 15-20 conditions (15 in Acoustically Similar, 16 in Semantically Similar).
PROCEDURE: The PP’s were split into four groups according to IV (1) and (2). Each group views a slideshow of a set of 10 words. Each word appears for 3 seconds.
In the Acoustically Similar condition, the PP’s get a list of words that share a similar sound (man, cab, can, max etc.) but the Control group get words that are all simple one syllable words that do not sound the same (pit, pew, cow, pen).
In the Semantically Similar condition, the words share a similar meaning (great, large, big, huge etc,) but the Control group get words that are unconnected (good, huge, hot, safe etc.)
The PP’s in all 4 conditions then carry out an ‘interference test’ which involves hearing then writing down 8 numbers three times. They then recall the words from the slideshow in order.
There are four ‘trials’ and the PP’s get better each time they do it because the words stay the same. The worlds themselves are disp;syed on signs around the room so the PP only concentrates on getting the ORDER of the words right, not remembering the words themselves.
After the 4th tricks, the PP’s get a 15 minute break and perform an unrelated interference task. They then are asked to recall the list again. This fifth and final trial is unexpected. The words themselves are still on display but the PP’s have to recall the word order.
RESULTS: Baddeley was interested to see whether Acoustic or Semantic similarity made it harder to learn the words. He compared the scores of the PP’s in the Similar and Control conditions and paid particular attention to whether they recalled as well as in the 5th forgetting trial to see if there was a decrease in scores.
Acoustically similar words seem to be confusing at first, but PP’s soon ‘catch up’ with the Control group and even overtake them, but this isn’t statistically significant.
Semantically similar words do seem to be confusing and the experimental group lags behind the Control group. The experimental group performs worse overall and scores are lower.
CONCLUSIONS: Baddeley concludes that LTM encodes semantically, at least primarily. This is why LTM gets confused when it has to retrieve the order of words which are semantically similar. It gets distracted by the semantic similarities and muddles them up. It has no problem retrieving acoustically similar words because LTM pays no attention to how the words sound.
The “slow start” in the Acoustically Similar condition would be because the interference task doesn’t block STM 100% - some of the words linger on in the rehearsal loop. This means in most conditions, the participants’ LTM gets a bit of help from STM. But in the Acoustically Similar condition, STM gets confused by the similar sounds the way that LTM gets confused by similar meanings. It can’t be of much help so this group lags behind the Controls until all the words are encoded in LTM, at which point the two groups finally get similar scores.
COGNITIVE PSYCHOLOGY
classic study (AO3)
(AO3) EVALUATING BADDELEY
generalisability
STRENGTH: Baddeley has a large sample of 72. Any anomalies will be averaged out in a sample this size, meaning that there will be no risk for people with unusually good or bad memories skewing the results. This suggests that you can generalise from this sample. However, there were so many conditions in this study that each group only had 15-20 people in it. That’s not a lot. Only 15 people did the Acoustically Similar condition. An anomaly could make a difference to scores with numbers that small.
WEAKNESS: A volunteer sample might have people with particularly good memories who enjoy doing memory tests, which is not representative of people in general.
reliability
STRENGTH: This study is a reliable study because it has a standardised procedure that you can replicate yourself and is an easy procedure. Baddeley also improved the reliability of his study by getting rid of read-aloud word lists because some PP’s had hearing difficulties which could skew the results. Instead, he replaced them with a slideshow and everyone saw the same word for the same amount of time (3 seconds).
application
STRENGTH:The main application of this study has been for other Cognitive Psychologists, who have built on Baddeley’s research and investigated LTM in greater depth. Baddeley’s use of interference tasks to control STM has been particularly influential. Baddeley & Hitch built on this research and developed a brand new memory model – Working Memory. Another application is for your own revision. If LTM encodes semantically, it makes sense to revise using mind maps that use semantic links. However, reading passages out loud over and over (rote learning) is acoustic coding, but LTM doesn’t seem to work this way, so it won’t be as effective.
validity
STRENGTH: Baddeley took trouble to improve the internal validity of his experiment. He used controls to do this. Rather than getting participants to recall words, he asked them to recall word order (with the words themselves on display the whole time). This reduced the risk that some words would be hard to recall because they were unfamiliar or others easy to recall because they had associations for the participants.
WEAKNESS: However, the ecological validity of this study is not good. Recalling lists of words is quite artificial but you sometimes have to do it (a shopping list, for example). Recalling the order of words is completely artificial and doesn’t resemble anything you would use memory to do in the real world.
(COUNTER) Baddeley did improve this. For example, he made the 5th “forgetting” trial a surprise that the participants weren’t expecting. This is similar to real life, where you are not usually expecting it when you are asked to recall important information.
what is the contemporary study in cognitive psychology?
Sebastien and Hernandez-Gil (2012)
COGNITIVE PSYCHOLOGY
contemporary study (AO1)
COGNITIVE PSYCHOLOGY
contemporary study (AO3)
what is the classic study in biological psychology?
Raine et al. (1997)
Brain Abnormalities in Murderers
BIOLOGICAL PSYCHOLOGY
classic study (AO1)
AIM: To find out if there is a difference in the structure of brain activity between people who have committed murder (NGRIs) and non-murderers. In particular, Raine looked at the role played by the prefrontal cortex, the corpus callosum, the amygdala and the medial temporal lobe/hippocampus and the thalamus in predisposing people towards aggression. Raine wanted to see if the findings of studies linking brain structure to aggression in animals could be generalised to humans.
IV: Whether the participant is an offender pleading NGRI to murder, or a non-murder in the Control Group. Since the IV is naturally-varying and the controls were matched on age and sex, this is a natural experiment and independant groups design because Raine did not pair each PP’s results with their ‘opposite number’.
DV: Relative glucose levels in the prefrontal cortex, the other lobes of the brain, the corpus callousum. , the amygdala, the hippocampus and the thalamus as revealed by PET.
SAMPLE: 41 offenders pleading NGRI to the crime of murder and 41 Controls. The NGRI’s were 39 men and 2 women: 23 had a history of brain damage, 3 had a history of drug abuse, 6 suffered from schizophrenia, 2 with epilepsy and 7 with other emotional disorders. The controls were people of the same age and sex with no history of mental illness or crime, except 6 controls who had schizophrenia. The NGRI’s should be considered an opportunity sample.
PROCEDURE: The participants were tested at the University of California. Each was injected with the glucose tracer and then performed the Continuous Performance Task (CPT) for 32 minutes. Then the PET scan was carried out.
Raine used other experimental controls:
The participants were allowed to practice the CPT ten minutes before the glucose tracer was injected to make sure they were all equally familiar with it.
Raine made sure none of the participants (NGRIs or Controls) was on medication; the NGRIs had been kept medication-free for 2 weeks before the PET scan.
RESULTS: He found that NGRI’s showed less activity in the frontal lobe, especially the prefrontal cortex that is associated with rational thinking, self-restraint and memory. There was also less activity in the parietal love, which is associated with abstract thinking such as ‘morality’ or ‘justice’. In the sub-cortical region, the NGRI’s had less activity in the corpus callous, which is associated with long-term planning. There was also an imbalance of activity between the left and right hemispheres in the limbic system. There was less activity on the left and more on the right in the amygdala and hippocampus. There areas are associated with aggression.
CONCLUSIONS: Raine suggests how brain abnormalities might translate into violence or anti-social behaviour. Prefrontal deficits (deficits are lack of activity) might make someone more impulsive and emotional.
Deficits in the limbic system might make someone aggressive, as was observed in cats; the amygdala controls urges and desires, the thalamus processes information and the hippocampus processes memory (see the study by Schmolck et al.). Deficits might make it hard for someone to learn from mistakes or understand their emotions.
Deficits in the corpus callosum make it harder for the brain’s hemispheres to communicate, making it difficult to think through long term consequences and make decisions
Areas like the parietal lobe, amygdala and hippocampus have a part to play in recognition; deficits here might make it harder for someone to judge social situations, leading them to overreact.
Raine concludes that findings from animal studies into aggression can be generalised to humans and there is a link between brain structure and aggression. Raine is optimistic that these brain deficits can be prevented if they are identified early enough.
TO NOTE:
Raine is not claiming that violence is purely biological. He thinks social and situational factors also play a part.
The study doesn’t show the causes of these brain deficits- whether the PP’s were born this way or acquired them later.
Raine insists that these results do not show that the NGRIs had no free will or that they couldn’t help themselves when they committed their crime. Brain structure can only give us a predisposition towards acting a certain way; the choice is still ours.
BIOLOGICAL PSYCHOLOGY
classic study (AO3)
generalisability
STRENGTH: Raine et al. uses a large sample (82) which was the largest at the time for this sort of study. Anomalies such as PP’s with unusual brain structure or people who disrupted the test by not focusing on the CPT could not skew the data too much. This makes the results representative of a wider population.
WEAKNESS: On the other hand, the NGRIs are unusual offenders. They are people who have killed someone, but either don’t remember doing it or are too confused to stand up to trial. These people are not representative of ‘typical’ murderes, still less of tropical violent individuals. As Raine pointed out, not all of the NGRIs killed their victims violently.
reliability
STRENGTH: PET is a reliable brain imaging technique that has been used (with growing a success) since the 1970s. It produces objective and replicable results and it can be tested and re-tested to check its reliability. The CPT also ensures that all PP’s were concentrating on the same thing, which ensures they all had similar types of brain activity. This is a standardised procedure that adds to the reliability.
WEAKNESS: However, Raine admits that there were still problems with the reliability of PET scanning in the 1990s. The results were sometimes unclear and had to be interpreted, which introduces subjectivity and low reliability.
applications
*Raine is NOT claiming that PET scanning could identify murderers in advance or is he claiming that PET scans could help decide whether or not someone is guilty of murder.
STRENGTHS: Raine does however, suggest that if the damage that causes these brain deck fits can be prevented, people might be prevented from becoming murderers as they will not develop a murderous predisposition. This involves early intervention with at-risk children in school, programmes to steer young people away from drugs and monitoring people who have received brain injury.
validity
STRENGTH: Bufkin & Luttrell (2005) carried out a meta-analysis, where they analysed the results of 17 studies that use brain imaging to study aggression in humans (Raine et al. is one of the studies they analysed). They found that all the studies point to similar conclusions: impulsivity is linked to deficits in the prefrontal cortex or the amygdala and such people have difficulty coping with negative emotions. This adds to the construct validity of Raine’s study, since it shows the results tie in with the findings of lots of other studies.
WEAKNESS: The CPT used by Raine could be criticised for being artificial and unconnected to violence or provocation. The participants were all doing an unusual task and in an unusual state of mind when the PET test was carried out. This lowers the ecological validity of the study.
WEAKNESS: As a natural experiment, this study cannot show cause-and-effect. For example, the NGRIs might have developed their brain deficits after the killing, because of the stress of the event, their arrest and imprisonment and their coming trial. The study only looks at brain activity and this could be a very reductionist view of human behaviour: an explanation from one narrow perspective that doesn’t take in “the big picture”. To be fair, Raine makes a point of explaining that personal, social and cultural influences might be at work as well as brain deficits. Another study that looks at genetic and environmental factors behind aggression is Brendgen et al. (2005).
ethics
STRENGTH: The NGRIs agreed to have the PET tests because it would help their court case, either by showing they were not fit to stand trial or acting as evidence that they weren’t in control of themselves when they committed the crime The Controls all gave their prior consent to be tested and for their imaging data to be used in the study. The University of California approved the study. If the NGRIs or the schizophrenic Controls were not competent to consent, then presumptive consent was given by their lawyer or carer.
WEAKNESS: There are ethical concerns with the conclusions for a study like this. It seems to suggest that some people are driven to kill by their brain structure and that their violence is out of their control. It invites us to “screen” prospective job candidates, perhaps even potential partners, to check they don’t have “a murderer’s brain.” Raine and his colleagues make it clear they are NOT drawing these conclusions themselves, but once a study like this is known to the public its conclusions may be misinterpreted. This would go against the social responsibility of ethical research.
