Biological Psychology - Basics

AO1: Gottesman and Shields (1966) - Aim

If SZ has genetic basis

AO1: Gottesman and Shields (1966) - Sample

62 SZ patients (31m, 31f) All hospitalised before 1964. 24 MZ twins, 33 DZ twins identified using eg blood grouping.

AO1: Gottesman and Shields (1966) - Procedure

- Hospital notes
- Semi structured interviews with twins and parents
- 30 min tape recording of speech
- Personality tests
- Psychometric tests

AO1: Gottesman and Shields (1966) - Results

- 42% MZ twins, 9% DZ twins diagnosed with SZ
- Average rate of SZ in general population was 1% therefore, person that is a MZ twin is 42 times more likely to have SZ

AO1: Gottesman and Shields (1966) - Conclusion

Closer genetic link, more likely twins have SZ. But MZ concordance rate was below 100% so genes may lead to liability towards SZ but needs to have environmental trigger.

AO3: Gottesman and Shields (1966) - Generalisability

Low - only used SZ twins that were hospitalised before 1964 so not representative of non-twin population so results of SZ basis won't apply completely

AO3: Gottesman and Shields (1966) - Reliability

High - Quant data collected in terms of % of twins with SZ to make comparisons so can help understand SZ basis

AO3: Gottesman and Shields (1966) - Population validity

High - wanted to study relation between genetics and SZ using MZ and DZ twins (controlled variables)

AO3: Gottesman and Shields (1966) - Interpretator bias

Low - can allow bias to occur when listening to SZ patients tape recordings therefore SZ basis could be misinterpreted

AO3: Gottesman and Shields (1966) -Useful

Can carry out further research to understand how genes are involved in SZ

AO3: Gottesman and Shields (1966) -Less Useful

Difficult to separate nature vs nuture as SZ basis so can only find relationship

AO1: Kety et al (1968) - Aim

Finding genetic basis in SZ by comparing adoptive and biological family of SZ patients

AO1: Kety et al (1968) - Sample

- 34 SZ patients (mostly DZ twins) taken from Danish Adoption Register, aged between 20-43.
- Split into 3 groups: Chronic sufferer, Short-term sufferer, borderline diagnosis
- Matched to 33 non-SZ adoptees based on age of adoption and gender and social class of adoptive family

AO1: Kety et al (1968) - Procedure

- Used Danish family records, tracked down 463 records. Used mental health register to assess mental status.
- Relatives diagnosed by psychiatrists who were unaware of the relation to patient (blind test)
- Diagnosed into 3 categories: B (alike adoptive child), C (inadequate personality), D (diagnosis unclear)

AO1: Kety et al (1968) - Results

- More signs of SZ in both adoptive child and their biological family than adoptive family.
- More SZ found in adoptive biological family that control biological families
- Out of 150 biological relatives, 8.7% had SZ or inadequate personality compared to 1.9% in biological families of control sample.

AO1: Kety et al (1968) - Conclusion

- SZ has genetic component.
- Adoptive sample had more SZ in biological families than control sample

AO3: Kety et al (1968) - Generalisability

Low - only used SZ twins from Danish adoption agency so results of SZ basis not representative of other countries like UK

AO3: Kety et al (1968) - Reliability

High - collect quant data in terms of % of adoptive children with SZ to be compared to biological parents, objective, can gain better understanding of SZ basis.

AO3: Kety et al (1968) - Blind test

High - Less open to bias from psychiatrists about link between genes and SZ using adoptive twins, ppt and psychiatrist variables controlled, high validity

AO3: Kety et al (1968) - Quant data

Low - collecting quant data won't produce result of why there is a genetic link or specific types of SZ therefore limited explanation of SZ basis as only shown in twins

AO3: Kety et al (1968) - Useful

Extra help can be offered to adoptive families who adopt child with family history of SZ

AO3: Kety et al (1968) - Not useful

Could lead to discrimination of children up for adoption as they would be less likely to be adopted

Function of frontal lobe

Involved in higher cognitive functioning like problem solving, decision making, reasoning including motor skills and expressive language

Function of parietal lobe

Information processor like processing language

Function of occipitial lobe

Visuospatial processing, colour differentiation and motion perception

Function of temporal lobe

Hearing some aspects of language and memory making

Function of cerebellum

Motor control co-ordination of movements, motor learning

Function of spinal cord

Transmission of nerve signals from body to brain

Function of left hemisphere

- Sensory stimulus from right side of body
- Motor control of right side of body
- Speech, language, comprehension
- Analysis, calculations
- Time and sequencing
- Recognition of words, letters, numbers

Function of right hemisphere

- Sensory stimulus from left side of body
- Motor control of left side of body
- Creativity, spatialability
- Context, perception
- Recognition of faces, places, objects

Function of corpus callosum

Connects two hemispheres and enables communication between the two ("information highway")

Function of thalamus

Brain relay station, passes on information from senses

Function of hypothalamus

Regulates eating, drinking, release of sex hormones (testosterone, oestrogen)

Function of amygdala

Processes emotional responses, memory, decision making

Function of hippocampus

Memory consolidation, navigation, spatial awareness

Function of basal ganglia

Processes movement information and planning responses, linked to habit learning and reward

AO1: Brain scanning - CAT scan

- Multiple X-ray images of the brain from different angles.
- Researchers examine structure of brain "slice by slice" making cross sections.
- 3D images created from large series of 2D images

AO1: Brain scanning - PET scan point 1

- Radioactive tracer containing glucose (metabolised by body) injected into bloodstream.
- Positrons in tracer send signals to scanner, records level of brain activity.

AO1: Brain scanning - PET scan point 2

- 3D images made
- 2 scans carried out (active and inactive) to make comparisons of activity during task
- Scans colour coded to indicate areas of high/low glucose metabolism

AO1: Brain scanning - FMRI scan

- Measures brain function by looking at blood flow detecting changes in level of oxygen delivered to brain.
- Scan monitors changes in blood texture and colour delivered to brain.
- Most active areas where blood is oxygen rich

AO3: Scans - Reliability

High - Standardised, measuring biological functions within the brain eg measuring metabolism of glucose, can replicate to check for consistency

AO3: Scans - Quant data

High V - objective, which means there won't be any interpretation bias therefore more accurate measure

AO3: Scans - Ecological validity

Low - Carried out in controlled settings rather than the natrual environment meaning that less accurate as brains will function differently when in a natural setting

AO3: Scans - Subjectivity

Low - The images taken from the scans may need to be interpreted by researchers meaning subject to intepretation bias, less accurate

AO3: Scans - Useful

Allows us to detect problems in the brain like TBI so then we can develop treatment programmes

AO3: Scans - Less useful

Reductionist, like assumption that criminal behaviour is due to the brain and doesn't consider environmental factors