Biological Flashcards

Question

Apply Issues and debates to effect of brain structure on aggression?- Psychology as a science

Answer 1

· Psychology as a science- Use of animals in psychological investigations allows for scientific rigour to be applied. More control is possible as animal can be genetically bred for specific study and their environment is carefully monitored. This removes chance of extraneous variables affecting the outcome the study, making the studies using animals extremely well controlled, enabling objective data to be gathered, leading to clear cause and effect conclusions being drawn. This level of control would not be possible with human participants due to ethical considerations. · Using objective data collection such as PET scans (Factual) and experiments which are controlled give a scientific basis.

Answer 2

Raine et al. (1997) Aim: To investigate if there is a difference in the structure of the brain activity between people who have committed murders (NGRI's- Not Guilty for Reason of Insanity) and non-murderers Hypothesis: That participants pleading NGRI would show brain dysfunctions in areas of the brain associated with violence.

Answer 3

Aim- To investigate brain abnormalities and aggressive behaviour in murderers (NGRI) Sample- Two groups of 41 people, 39 males, 2 females in each group. Sample is somewhat large (82 People) which was largest at time for study, results representative of wider population. The sample is androcentric, uneven balance of males and females in group, this is a limitation as results regarding brain and behaviour may be difficult to generalise to females. Method 1- The study used PET scanning. AO3- PET is an objective, brain-imaging technique which can be easily replicated, re-tested for reliability, however the interpretations of the PET may be subjective due to the unclear images/results which can lower reliability. Method 2- Controlled and standardised procedure increases cause-and-effect of brain structure + aggression, higher internal validity of results. Raine used CPT CPT used by Raine can be criticised for being artificial, including the idea of participants using unusual task in unusual mental state, which can lower ecological validity of study as it’s unrepresentative of everyday life. Results Application- Application to real life because it provides the possibility that biological factors impact murderer's behaviour and you can predict a person's future, violent behaviour, could be used to determine/predict whether teenage violence will be continued and whether prisoners should be released. Brain dysfunction in NGRI group was in areas previously implicated with violent behaviour. Compared to control groups, murderers shown-Lower activity in prefrontal cortex (Lateral and medial areas) Asymmetrical Amygdala, Medial Temporal lobe, and thalamus activity (All had lower in left side but higher in right) Conclusion Brain differences associated with many behavioural changes that can be related to violent behaviour. For example, dysfunction in prefrontal cortex linked to impulsivity, lack of self-control, inability to learn from behavioural consequences. Hippocampus, amygdala, thalamus related to learning, suggests criminals unable to modify behaviour as they can’t learn from consequences of actions. General Conclusion- Study is strong in the fact that it used an objective data collection method (PET Scans) which increase reliability in study and that results, aims and conclusions are highly applicable to understandings of biological effects on murderer behaviour and whether prisoners should be released or not, based on their brain structure, however the study has limitations such as the effect of extraneous variables and situational factors on results (Lower internal validity), and the androcentric sample (39 men, 2 women) which limits generalisability of results regarding brain damage to women.

Answer 4

· Social Control (Controlling people)- in Mid-20th century, knowledge was used to "treat" aggressive mental patients by performing prefrontal lobotomy (Operation that severed connection between limbic system which is part of our reward pathway, and prefrontal cortex), this was effective in reducing aggression but it also reduced all other emotional reactions to and is no longer considered as ethical. Common practice as biological approach was widely popular ·

Answer 5

Reductionism- It could be argued that brain functioning as an explanation for aggression is reductionist. It reduces the production of aggressive behaviour and all that entails down to working of specific neural circuits and ignores all other possible causes such as social learning. There are cultures that show much higher than average aggression and cultures that show much lower levels. This is unlikely to be due to differences in brain structure but very likely caused by social learning. · Reductionist- Simplifying human behaviour to very specific factors (Reduces/ignores influence of other aspects I.e. people, environment, lifestyle) · Biological Point of view highly reductionist

Answer 6

· Determinism- The argument is known as biological determinism, which is the view that your behaviour is predetermined by your biological makeup and you as an individual have no free will/ choice as to how you behave, so those people with smaller amygdala and low activity in prefrontal cortex are destined to be aggressive. · These ideas can be used as defence for violence with the argument that aggressive behaviour of some offenders could be result of genetic determination and biological makeup, as was the case in Raine's research. · This could provide excuse for some people to be violent as they can say behaviour is beyond their control and therefore they're not responsible for violent outbursts, could limit willingness to engage in treatments such as anger management programmes as they may believe them to be useless in the face of biological factors, if behaviour is predetermined. Ignoring nurture effect on behaviour. · Determinism- Determinism in psychology is the philosophical position or assumption that all events, including human behaviour, have a specific cause that is predetermined

Answer 7

Procedure: Sample- Two groups of 41 people, 39 males, 2 females in each group. (82 people in total) Experimental group- 41 criminals with convictions for murder/manslaughter who were being tested to gain evidence to support claim of NGRI. Of these: * 6 had schizophrenia * 23 had suffered organic brain damage/head injury, * 3 were substance abusers Control group matched with experimental group on age and gender. Screened for general health (Physical examination, medical history, psychiatric interview), participants excluded if they had history of seizures, substance misuse, head trauma, consent obtained from all participants before PET was administered. All participants given continuous performance task (CPT) to complete. Sequence of blurred numbers to focus on. Participants started CPT as a practice trial 10 minutes before being injected with Flucodeoxyglucose (FDG). After 32 minutes on CPT, PET scan completed to measure metabolic rate in different brain areas to look at activity levels in areas. (PET done on ppts who were medication free for 2 weeks)

Answer 8

Findings: Brain dysfunction in NGRI group was in areas previously implicated with violent behaviour. Compared to control groups, murderers showed: * Lower activity in prefrontal cortex (Lateral and medial areas) * Higher activity in occipital lobe * Identical activity in temporal lobe Asymmetrical Amygdala, (had lower activity in left side but higher activity in right side) Conclusion: Brain differences associated with many behavioural changes that can be related to violent behaviour. For example, dysfunction in prefrontal cortex linked to impulsivity, lack of self-control, inability to learn from behavioural consequences. Hippocampus, amygdala, thalamus related to learning, suggests criminals unable to modify behaviour as they can’t learn from consequences of actions.

Answer 9

Aim- * See if social aggression could be caused by genes or environment. * See if social aggression shared same cause as physical aggression. * See if one type of aggression leads to another type. Sample * Participants for study recruited from Quebec New-born Twin Study (QNTS) and were all pairs of twins born between November 1995 and July 1998. * 322 pairs tested, 234 had complete data at all stages. * Of these pairs, 33 were MZ Males, 50 were MZ females, 41 DZ males, 32 DZ females, and 67 were mixed sex DZ twins

Answer 10

Procedure * Data from sample gathered at 5,18,30,38, 60 months, then again at age 6 as final data. Data consisted of two ratings of twin’s behaviour, one from teacher, one from classmates, gathered in spring term to ensure pps are well known and behavioural ratings are accurate * Teacher ratings based on statements from Preschool Social Behaviour Scale (PBBS, Crick et al 1997) and Direct and Indirect aggression scale (Bjorkvist, Lagerspetz et al 1992) such as “To what extent does the child get into fights” (Physical Aggression) and “To what extent does the child try to make others dislike a child” (Social Aggression) * Each statement scored on 3-point scale (0=never, 1=sometimes, 2=often) * Peer ratings done with classmates by fiving each child in twin’s class a booklet containing photos of children in class, children asked to circle three pictures of children that matched behavioural descriptions like examples before * Each twin given physical and social aggression score from teacher ratings. * Peer selections on social or physical aggression descriptors that were made of each twin also recorded.

Answer 11

Results Scores for social aggression similar between MZ and DZ twins. Scores for physical aggression more similar in MZ twins both from teachers and peers than in DZ twins. Conclusion Data suggested physical aggression may lead to social, but social aggression won’t lead to physical. *Strong genetic component to physical aggression but not social, which may be caused by environmental effects. * Children more physically aggressive showed more social aggression because of interaction of genes and environment. * As children grow, they become more socially aggressive because of social conventions on physical violence and developing different ways to express themselves

Answer 12

Sample- 332 Twin pairs from Quebec New-born twin study, born between November 1995 and July 1998 234 participants used in results (All gathered) MZ- Male- 44, Female- 50, DZ- Male- 41, Female-32, Mixed pairs – 67 Sample is strong in the fact that it is large, meaning that anomalies (Children with too high or too low aggression levels) will be averaged out, more representative and more generalisable, however a limitation of the sample is that it excluded 88 ppts who may have unique or unusual backgrounds, may limit generalisability of study (Limitation). Method 1- Study didn’t control for extraneous variables i.e. twins influencing one another’s behaviour, which can limit internal validity of results (Limitation).Twin studies are a valid means of studying nature vs nurture - MZ twins share 100% of their genotype, DZ no more than 50% - both share same home life - if MZ twins share behavior that DZ do not, it's likely due to genotype Method 2- Study uses pre-existing questionnaires which can be replicated and results can be tested for reliability (Strength), the questionnaires are limited in reliability as they were translated, questions could be mistranslated and original question could be lost, resulting in inaccurate answers (Weakness). Conclusion- Physical aggression caused by genetics and social aggression caused by environmental factors Physical aggression can result in social aggression i.e. Young child may be physically aggressive, as they grow they may develop in language and cognition, leading to them developing more socially desirable way of aggression (Social aggression) The conclusions have high application to early interventions for social aggression to prevent factors such as bullying occurring, if a child of young age is showing early signs of physical aggression, this insinuates social aggression may occur, so should provide anti-bullying classes alongside interventions for physical aggression (Anger-management). (Strength) To conclude, study is highly strong in its replicable method of questionnaires which allows for results to be tested for reliability, the results are highly applicable to understanding and intervening in social aggression, however the study lacks control, resulting in lowered external validity of results, study involves limited, unrepresentative sample (88 Ppts excluded) which limits generalisability for results.

Answer 13

Evolution and aggression In evolutionary terms, success is measured by production of offspring that survive to reproductive maturity. In the EEA, successful males physically bigger and stronger so would be those most capable of providing of and protecting mates and offspring. Psychologically, males would have adaptive advantage as they were naturally more aggressive when resources were threatened. Gave advantage of mate choice. Successful females chose mates who provided good genes, big, strong men favoured. Such men were also more likely to provide better resources in terms of food (Hunting and keeping food safe) and protection towards offspring and women against predators and other males who may kill wife or offspring, suggesting that those who displayed aggressive traits would be more successful than those who didn’t, competition for mates has driven masculine aggression. Male brains do have minor structural differences in comparison to females partially due to much higher testosterone exposure before and after birth. It has been argued that these differences are linked to typical male attributes and abilities such as spatial awareness. Ancient skulls and fossils may show that trepanning was used to investigate effect of brain structure on aggression. (Drilling holes into brain as surgical intervention) Post-hoc theory as developed to fit the Theory would also suggest that females would be less physically aggressive as it’d be an evolutionary disadvantage for females who’d spend long time-periods pregnant, breastfeeding, looking after vulnerable young children to ensure their survival and gathering foods such as fruit and berries. According to evolutionary psychology, this is why female aggression is more verbal/emotional instead of physical. Buss (1999) proposed that females would still be in competition for best mates but achieved victory by criticising other females to potential mates to make them appear less attractive. Hypothesis has been experimentally tested and found support. Males in general have higher testosterone levels than females, especially during puberty which may increase aggression. Great deal of evidence suggesting that testosterone levels are associated with aggression, e.g Mazur 1984 showed a marked increase in inter-male fighting around puberty where rapid increase in testosterone occurs. If these ideas are valid, we may expect physical difference in brain structure/chemistry of males and females, which would lead to greater expression of aggression in males. We would also expect to see greater degree of aggression among males than among females and those animals to which we are more closely genetically related would show similar behaviour. Ultimately, any evolutionary theory is developed to fit facts, difficult to prove ideas as cannot be scientifically tested and there’s limited fossil records for behaviour, EEA cannot be empirically tested.

Answer 14

CAT Passing X-rays into the head, but unlike a standard X-ray where beam is focused on specific area, multiple beams are passed around head at different angles to gather info. Detailed images developed by computer interpretation. Strengths * They're quick to conduct and can give accurate details of brain structure to advise treatment and plan a surgery. Weaknesses * X-rays in CAT can pose a risk to patients as they involve radiation exposure, Strength/Resolution- cost-benefit analysis conducted where they're only used if benefit of diagnosis outweighs radiation risk. * X-ray exposure can damage unborn baby of pregnant women

Answer 15

PET Form of nuclear medicine procedure, they involve injecting the patient with a small amount of radioactive material in order to conduct the scan. Patients having PET scan of brain will be injected by Fluorodeoxyglucose (FDG), which is tracer substance absorbed into the bloodstream. A task may be used to stimulate their brain (Raine et al 1997) and encourage activity. As brain is working, gamma rays produced in areas of high activity and these are picked up by scanner. Areas of high activity may have a red colour while areas of low activity may have blue colour. Strengths * May predict what kind of issues patients may face in low brain activity areas. * Useful In investigating brain areas which aren't functioning properly. * Compare functions between normal and abnormal brains so can identify causes of differences in behaviours. * Produce quantitative data which is reliable. * Used in research such as Raine et al (1997) where PET scans were used to investigate brain activity of murderers and control group of non-murderers Weaknesses * Scans more invasive as patient may be injected with radioactive substance, but carries low risk due to very low levels of substance, unclear long-term effects may reduce use of PET. * Carried out in controlled setting so cannot show how brain responds in real - life situations, therefore low in predictive validity. * Involve use of unrealistic tasks so results are low in ecological validity.

Answer 16

Designed in 1990's to enable images of brain activity to be gathered without the use of radiation, the idea behind it, is that brain activity may be associated with blood flow in the brain and activity is used to produce a picture. Having your head be placed inside functional electromagnet. Inside magnetic field, the nuclei within hydrogen molecules in water align with direction of magnetic field. As neural activity increases in the brain, blood flow increases in the active areas to keep up with demand for oxygen. Oxygen is carried to neurons in haemoglobin within red blood cells. Haemoglobin, when carrying oxygen, repels magnetic field (diamagnetic) and, when deoxygenated, it will follow direction of magnetic field (paramagnetic), these changes will be detected to create an image. Scanner sends information to computer that creates map of activation of changing levels of neural activity in different brain areas as tasks are being completed. * High comparative safety compared to other scans such as PET scans which use radiations. * Non-invasive and don’t use radiation risks of PET. * Used in research such as Montag et al 2011, where fmri showed that gamers had lower levels of activity in reaction to pictures of negative emotion than control group did. * Certain People may be unable to have these scans, such as people with pacemaker or surgical implants. * Some people may be claustrophobic and uncomfortable with idea of being in machine, not suitable for all patients.

Answer 17

Provides an overall view of brain electrical activity as a large no. of electrodes are placed over the surface of the skull. These pick up the activity of millions of neurones, by measuring the amplitude (size/intensity of electrical activity) and frequency (speed/rapidity of electrical activity). There are two distinctive states of the EEG: synchronised pattern where a recognised waveform can be identified and desynchronised pattern where there is NO recognisable waveform. Strengths Useful for identifying the general state of the brain (e.g., we can most commonly find synchronised patterns in our sleep) * Advantage of the EEG/ERP technique is that it has good temporal resolution: it takes readings every millisecond, meaning it can record the brain’s activity in real time as opposed to looking at a passive brain. This leads to an accurate measurement of electrical activity when undertaking a specific task. Weaknesses However, it could be argued that EEG/ERP is uncomfortable for the participant, as electrodes are attached to the scalp. This could result in unrepresentative readings as the patient’s discomfort may be affecting cognitive responses to situations. fMRI scans, on the other hand, are less invasive and would not cause the participants any discomfort, leading to potentially more accurate recordings. Does not relate to actual brain locations as clearly as scanning techniques do.

Answer 18

Monozygotic/Identical twins share 100% of genes while dizygotic/Fraternal only share 50% of same genes. When investigating twins, psychologists able to compare behaviour between group of identical and group of fraternal twins to see which group shared most similarity between each twin set. Evaluation Extent to which behaviour is same for twins is known as concordance rate, for example, Gottesman and Shields (1966) studied twins over a 16-year-period, where one had been diagnosed with schizophrenia, found that, in monozygotic twins, 42% of their co-twins was diagnosed with schizophrenia, while in dizygotic, was only 9% of co-twins diagnosed with same illness. Because concordance rate higher in Monozygotic then dizygotic twins In Gottesman and Shields, study concluded genetic element in developing schizophrenia. If concordance rate was equally high/low for dizygotic twins for any behaviour, then researchers might assume that there's no significant, genetic component at play and, in fact, experiential factors may have an effect, as twins are raised together and may share similar upbringing. Cocaro et al (1997) found in their study of 182 MZ twin pairs and 118 DZ pairs, that there was high chance of aggressive traits being found in both twins, suggesting that impulsive aggression could be due to genetic factors. They had their participants complete Buss-Durkee hostility inventory, 75 item questionnaire assessing various emotional traits associated with aggression and then compared to each member of twin pair, was found that a significant concordance rate was shown between twins for measures such as indirect assault, suggesting heritability role in some features of aggression.

Answer 19

Best method to allow psychologists to measure whether behaviour is result of nature or nurture. Groups of adoptees are studied and behaviour is correlated with adopted and natural families. Adoptees share no genetic material with adopted families but have shared environment throughout upbringing, however adoptees share 50% of genes with each biological parent, but haven't lived with them for majority of their life. If behaviour of adoptees correlated more strongly with biological family then adoptive, could be concluded behaviour involves biological component. Cadoret and Stewart (1991) suggested that adopted boys were at increased risk of attention deficit/hyperactivity and aggression as children if they had biological parent who'd been convicted of crime in adulthood. Found that boys were more likely to be aggressive or have a diagnosis of attention deficit/hyperactivity if there were psychiatric problems in member of adoptive family. Suggests that behaviour as complex as aggression can have variety of causes which can't be attributed to nature or nurture.

Answer 20

Overall evaluation: Many possible problems with twin and adoption studies, main aim investigates biological causes of behaviour, but difficult to separate nature completely from nurture. It may be rare for child to be adopted by a family immediately from birth so an adoptee may have spent time living with biological family or in foster care before adoption, possible confounding variables may affect validity of findings. Almost all twins will be raised together so may be problematic to assume that, because monozygotic twins show higher concordance for behaviour than DZ twins, must be genetic. Limited sample size limits generalisability. It's not easy to recruit a large and diverse group of MZ and DZ twins, or adoptees and their parents, reducing generalisability. Adoption studies may cause the problem of children who are being adopted tend to be placed in families that closely affect family background they came from, may be unreliable to assume that any similarities of adoptee and biological family are result of nature because similarity may be due to similar live events/experiences (Nurture).

Answer 21

Overall evaluation: Many possible problems with twin and adoption studies, main aim investigates biological causes of behaviour, but difficult to separate nature completely from nurture. It may be rare for child to be adopted by a family immediately from birth so an adoptee may have spent time living with biological family or in foster care before adoption, possible confounding variables may affect validity of findings. Almost all twins will be raised together so may be problematic to assume that, because monozygotic twins show higher concordance for behaviour than DZ twins, must be genetic. Limited sample size limits generalisability. It's not easy to recruit a large and diverse group of MZ and DZ twins, or adoptees and their parents, reducing generalisability. Adoption studies may cause the problem of children who are being adopted tend to be placed in families that closely affect family background they came from, may be unreliable to assume that any similarities of adoptee and biological family are result of nature because similarity may be due to similar live events/experiences (Nurture).

Answer 22

The aim of this correlational study is to investigate if little man syndrome exists and there is a relationship between height and aggression. Sample This correlational study used an opportunity sample of 18 psychology students in SCA Sixth form, which is in Smethwick Co-variables (operationalise them) 1. Height measured in cm Aggression scored generated from the Buss Perry Aggression Questionnaire (BPAQ) Standardised procedure 2. Complete the BPAQ online using their own laptop Add all 4 aggression scores to give an overall score for aggression Measured height in cm using a metre stick Standardised instructions 3. Answer the online questionnaire honestly Remove shoes before being measured To control ppt variables I carried out the study in the morning so students were not tired. I ensured all ppts took their shoes off so heels did not make a difference to their height. To control situational variables I carried out the study in the morning to get more accurate heights. Findings: The Buss Perry Aggression Questionnaire generated 4 types of aggression. They were: * Physical aggression * Verbal aggression * Hostility * Anger Table of raw data for height and aggression scores (DON’T NEED TO MEMORISE) Inferential statistical test: 1. Test of relationship Intervals (results are fixed measurements) Independent groups design Sum of difference squared = 572 1 – 0.59 = 0.41 Correlational co-efficient = 0.41 Critical values = 0.401 Concluded that there’s no correlation between aggression scores and height. Null hypothesis accepted

Answer 23

Evaluation Strengths Research had standardised procedure allowing for it to be replicated and re-tested so results can be proved to have reliability. Controlled participant and situational variables so that results regarding aggression and height may have high validify and causal relationship. Conclusions may be applicable as it can suggest that height stereotypes should not be used in suspect identification and in prosecution of suspects, can lower stereotypical nature of justice system. Limitations Sample is unrepresentative and small, only included 18 psychology students from Smethwick, results cannot be generalised to students who do other subjects, live in other areas, and go to other schools, to make sample more representative and results more generalisable sample should be recruited of participants from different areas, people from different areas, who do different subjects, and even people of different age groups and educational levels, such as school dropouts or university students. Opportunity sample may be limited due to fact participants may show demand characteristics, they may show interest in research area and want to appease to experimenter beliefs/suggestions, lowers validity of results regarding height and aggression, this can be improved by using different sampling method such as stratified sampling to reduce chance of all ppts being interested in area of research and showing bias and demand characteristics, as well as increasing generalisability of results regarding height and aggression. Social desirability bias may occur as participants may be aware of stereotypes such as little-man syndrome and may want to disassociate themselves from this, especially with participants who are short and may not want to be labelled as aggressive, which can lower validity of results, to resolve this, participants can be told fake aim, like investigating effect of height on speed of completing questionnaire on random topic, as this reduces chance of participants lying about their aggression.