Biological Psychology Flashcards
What are twin studies?
Test influence of nature/nature on human behaviour. Test MZ and DZ twins using concordance rates on probability of behaviour being genetic
How many genes do monozygotic (indentical twins) or Dizgotic (fraternal twins) share.
Monozygotic twins share 100% of genes
Dizygotic twins share 50%.
What are adoption studies?
Test whether behaviour is nature or nuture using adoptees adopted families and their natural families.
Adoptees share 50% of genes with each bio parent so if behaviour more similar to bio parent then it would be nature.
What does the frontal lobe do?
Involved in higher cognitive function such as problem solving, decision making and motor skills.
What does the Parietal lobe do?
Involbed in processing info from the senses. Also has inmportant role in language processing.
What does Occipital Lobe do?
Involved in visual processing of info including visuo spatial processing and colour differation.
What does Temporal lobe do?
Deals with some aspects of language and memory making.
What does the Cerebellum do?
Important in motor control, co-ordination of movement as well as motor learning.
What does the spinal cord do?
Transmits nerves signals from body to brain.
What does the Corpus Callosum do?
Connects the 2 hemisphere of the brain and enables communication between them.
What does the Thalamus do?
It relays info and passes it onto the senses.
What does the Hypothalamus do?
Regulates release of sex hormones (testerone and eostrogen)
What does the Amygdala do?
Has Primary role in processing emotional responses and memory and decision making.
What does the Hippocampus do?
Responsible for memory conslidation, navigation and spatial awareness.
What does the Basal Ganglia do?
Processes info on movement and planning responses.
What was the aim of the Li et al, contemporary study of heroin users.
To investigate if the posterior cingulate cortex is activated when given drug related cues and is stronger in heroin users. Suggesting possible brain damage being caused
What types of groups did Li use in his study?
Experimental group had 14 male heroin users in detoxyifying stage of treatment who used heroin for average of 89 months and had to be heroin free, mean age of 35
Control group had 15 males who matched experimental group on handidness, age, education, and all ptts were smokers had no head trauma and given informed consent.
What procedure did Li use in his study?
Did 3 scans:
1, structural scan of brain
2, they focused on crosshair in a 5 min resting fMRI scan
3, was 490 sec FMRI scan with 48 pics half being drug related half neutral
Each pic presented for 2 secs with average of 8 seconds between each pic
ppts asked to take craving scale before and after test from 1-10.
What were the Results of Li’s study?
Heroin users higher on craving scale (3.21) compare to control (2.23)
Positive correlation between activity in PCC and time being heroin user.
PCC more active in heroin user when shown drug images than control.
Stronger connection between PCC and insula (decision making) than controls and higher activity in dorsal striatum (drug taking beh)
the drug related images activated brain in heroin users but not the controls
What are some disadvantages of Li’s study?
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Restricted sample- only men no women. Social des- Users may lie about craving scale.
Low eco validity- Lab setting.
Used FMRI scans that need interpreting by researcher so some researcher bias and results less valid
What are some advantages of Li’s study?
Sci method- Objective using FMRI scans high validity results.
Standardised- pics 2 secs and 8 apart high reliability.
High control- Ppts Matched on age education etc
What was the aim of Raines 1997 study?
To show that murderers pleading not guilty for reasons of insanity (NGRI) would show dysfunction in areas od brain like pre-frontal cortex and amygdala which are associtaed with violence.
What types of groups did Raine use in his study?
In experimental group: 41 murderers 39M and 2F pleading NGRI for reasons like schizophrenia or drug use.
Control group: matched with experimental group on age, gender and diagnosis of schizo.
ALL ppts medication free for 2 weeks and had to take pyschiatric interviews.
What was the procedure of Raines study?
Starter with a 10 min trail of continuos performance task (CPT) focusing on blurred numbers.
Then injected with tracer and continued the CPT for 32 mins to allow tracer to metabolise. Then had to take PET scan
What was results of Raines study?
(Cortical areas) Lower glucose metabolism in prefrontal cortext (self control) than control group, and in cerebellum
(Sub cortical areas) Lower glucose in corpus callosum than control
Asymmetrical glucose in amygdala and Lower glucose in left amygdala and higher in right.
What are two advantages of Raines study?
High control- NGRI and control group were matched on age/gender so high val.
Highly scientific- used pet scans using tracer in brain meaning results are more valid and accurate
What are two disadvantages of Raines study?
Sample not representative: in experimental group all 41 had pleaded NGRI no account for regular muderers.
Interpretation bias: PET scans have to be interpreted by researcher so low reliabiltiy.
What was the sample of gottesman and shields twin study?
62 schizophrenic patients, equal no of males and females hospitalised before 1964. 24 MZ twins 33 DZ twins
Twins identified using tests like blood grouping.
What was the procedure of Gottesman and shields twin study?
Measured mental using methods like:
hospital notes
semi-structured interviews,
30 minute tape recording of speech
personality tests.
What were the results of Gottesman and shields twin study?
Severe schizophrenia confidence rate was for 2 year hospital stay was 75% for MZ twins but 24% for DZ twins.
More DZ had a healthy twin compared to MZ twins.
Concordance rates stronger for female twins than males
Shows closer genetic link=sz symptoms but not 100% so needs environmental trigger.
What are two weaknesses of Gottesman and shields study?
Sample isn’t representative as used twins from London- can’t generalise results to rest of UK as twins brought up differently
Low in validity as self report methods like interviews were used so there may be social desirability in lying about their sz symptoms
What are two strengths of Gottesman and shields study?
Scientific methods used to identify twins like blood grouping so results more valid and accurate
Variety of methods used like questionnaires and interviews=holistic view on how the twins and sz
Also quantitive data ;)
What was the sample for Ketys adoption study?
34 schizophrenic patients from Danish adoption register aged 20-43.
Participants split into 3 sz groups: chronic sufferers, short term sufferer and borderline diagnosis
33 healthy controls matched on age, gender and social class
What was the procedure or Ketys adoption study?
Used family records to track down relatives and used mental health register to asses their mental status
Relatives then diagnosed in blind test and put into 3 categories of:
Just like adoptive child, uncertain and inadequate
What were results of Ketys adoption study?
Found more sz disorders in adoptive child and biological family than adoptive family. Less in control group than adoptive biological family
More sz found in adoptive child biological family than control group [8.7% to 1.9%]
Shows sz has genetic component
What are two weaknesses of Ketys adoption study?
Sample not representative Only used adoptive children from Denmark so hard to generalise results about sz to non adoptees or people outside Denmark.
Not standardised- medical records different for each patient so less reliable in measuring sz and genetics
What are two strengths of Ketys adoption study?
High controls- participants matched to control group on gender, age and social class
Low in bias as psychiatrist diagnosed relatives in a blind tests so more valid results.
How do neurotransmitters work?
Electrical impulse trigger creates Action potential which stimulates vesicles
This releases a neurotransmitter
This then travels across synaptic gap and binds to receptors
Then it is either destroyed by enzymes or reuptaked
What is the dopamine neurotransmitter?
Its related to emotions like pleasure/rewards and addiction
What is serotonin neurotransmitter?
Deals with mood control, emotions like happiness and things like sleep
What is GABA neurotransmitter?
It is inhibiting neurotransmitter that reduces activity of neurons it binds too
What are PET scans?
Produces 3D image of the brain using radioactive tracer.
Shows activity of different parts of the brain- colour coded based on levels of activity.
During research they take a baseline of participants brain and then when injected stimuluses are shown to trigger the brain.
What are CAT scans?
Produces multiple black and white images of the brain using X-rays to picture angles and cross sections of the brain.
These 2D images can be converted to 3D showing abnormalities in brain structure.
What are FMRI scans?
Measure brain activity like blood flow using magnetic fields and radio waves to detect areas of brain oxygen level using blood flow.
Can be used to detect signs of brain disease like Alzheimer’s or affect of drugs but cant be used by everyone like people with metal implements due to the magnetic waves
What is an advantage of CAT, PET and FMRI scans?
PET scams have a standardized method of injecting a glucose tracer so more reliable and consistent on brain activity
CAT scans are useful as can identify differences in brain structure to detect things like tumors- can be used for surgery.
FMRI scans produce quantitive data of brain activity so little interpretation is needed as look at areas of brain function without bias
What is a disadvantge of CAT, PET and FMRI scans?
PET scans carried out in artificial setting using unrealistic tasks so not how brain responds in real world- low ecological validity
CAT scans only show structure of brain not the function so difficult in assessing changes in behaviour
FMRI scans less useful as cant be used by people with magnetic implants due to the magnetic fields so cant be used on everyone
What are two strengths of neurotransmitter explanation of behavior?
Reductionist as they simply reduce behavior like depression to low hormones such as serotonin which is useful as allows doctors to prescribe anti depressants
Another strength is from Dee Higley who studied monkeys who were injured in fights or fell off trees were more likely to have low serotonin levels which inhibits aggression, showing a link between serotonin and aggression.
Also scientific can see neurotransmitters in brain=objective :)
What are two weaknesses of neurotransmitter explanation of behavior?
Individual differences of behavior like how upbringing so incomplete explanation of behavior
A weakness is from Depatie that giving drugs increases dopamine and doesn’t create symptoms of schizophrenia like expected so its not only explanation of behaviors like sz
What is the effect of Heroin on neurotransmitters?
Increases dopamine in pathway by boosting dopamine synapses causing euphoria.
When dopamine return to normal levels to compensate causes dysphoria
Heroin also causes down regulating as dopamine stores are used up making the person reliant on heroin.
What’s the effect of alcohol on neurotransmitters?
Increases affect of GABA slowing down reaction time.
It increases dopamine in reward pathway and increases serotonin but over time it reduces causing depression.
What’s the effect of cocaine on neurotransmitters?
Blocks re-uptake of dopamine into pre synaptic neuron and binds to post synaptic neuron casing euphoria.
Brain then reduces production of dopamine causing them to want more to get feeling again.
What are two strengths of drugs affects on synaptic transmission?
Li’s study found heroin users had more activity in PCC compared to non heroin users suggesting reward pathways change when taking drugs and addiction is due to brain function
Highly scientific as can use brain scans to see affects pf drug use on synaptic transmission. This allows us to find objective reasons for addiction
What are two weaknesses of drugs affects on synaptic transmission?
Doesn’t consider environment becomes addicted due to brain function could be environmental factors like peer pressure or persons upbringing so less valid explanation
Low individual differences as as not everyone responds drug use the same due to differences in synapses so less valid explanation of addiction
What was the conclusion of Li’s study?
PCC activity in heroin users is different than in non users and linked to length of time as heroin user
Changes brain over time as environmental cues can trigger reactions in brain which can explain why heroin users relapse when see imagery related to drugs
