biopsychology ao3 Flashcards
(24 cards)
localisation of brain function (research support)
- researchers did brain scans while ppts did reading tasks
- wernickes and brocas area active during task supports parts of brain localised as wernickes for understanding and brocas for speaking
- strength as study uses scans
- objective method no bias or demand characteristics can affect it so control of extraneous variables = high internal validity
localisation of brain function (case study support)
- phineas gage had long pole go through cheek to brain taking out portion of frontal lobe
- personality changed from calm to angry
- supports theory as personality localised in frontal lobe
- idiographic study low pop validity just because he supports it doesnt mean everyone will
localisation of brain function (research against + animal extrapolation)
- researchers took out 10-50% of rats brain to learn maze = had no effect on rat learning maze
- shows that rat uses entire brain so support holisim over localisation
- animal extrapolation just because rat supports doesnt means humans will as different bodies
plasticity and functional recovery (research support for plasticity + low population validity)
- researchers found more grey matter in posterior hippocampus of taxi drivers than control
- this part of brain related to navigational skills
- mustve increased after learning the knowledge shows support
- low pupulation validity and we dont know if drivers had developed posterior from before = cant establish cause&effect
plasticity and functional recovery (research support for FR + animal extrapolation)
- researchers sewed one eye shut for kittens and then scanned analysed brains response
- found visual cortex related to eye was not idle but processing information for other eye
- supports FR as brain adapts to changes
- animals and humans different just because kittens showed support doesnt mean human brains like that
plasticity and functional recovery (real life application)
- understanding functional recovery and plasticity and how axonal growth occurs forming new connections contributes to neurorehabilliation sector
- allow develop new therapies like constraint induced therapy for those whove suffered strokes
- positive as helping people get better
circadian rhythms (research support)
- siffre spent several hours underground to study his biological rhythms
- each time his free running cycle went to 25 hours he would then sleep at normal schedule
- shows support of EPs in cycle as it settled down to a rhythm despite absence of EZs
- shows importance of EZs as natural cycle was not entirely circadian as 25 hours so need EZs to entrain cycle
- shows important interactions between EZs and EPs needed
circadian rhythms (reductionism)
- EZs seen as environmentally reductionist
- EPs seen as biologically reductionist
- better to take an interactionist approach for better understanding of sleep wake cycle
circadian rhythms (low internal validity)
- old study and exposure of artificial light was seen not to effect sleep wake cycles so study had torches etc
- later studies found even dim light could affect sleep wake cycle and cause it to be between 22 to 28
- therefore extraneous variables not controlled low internal validity not measuring what supposed to
role of EPs and EZs in sleep wake cycle (research support)
- researchers inserted SCN of mutant hamster (20 hour rhythm) into brain of normal hamster
- found normal hamster also ended up having cycle of 20 hours
- shows support for EP of SCN on sleep wake cycle
- highly controlled lab experiment as well study can be replicated = improves reliability
- less confounding variables = can establish cause and effect
role of EPs and EZs in sleep wake cycle (research findings animal extrapolation)
- research done on hamsters
- hamsters and humans have different needs and humans have much more complex social cues egs EZ
- EZ affect sleep wake
- so just because research findings support EP of SCN in animals not very clear in humans not sure if same effects
role of EPs and EZs in sleep wake cycle (EZs role may be overstated)
- some individuals EPs are set to withstand changes in environment
- blind man had cycle of 24.9 hours no matter change in social cues etc cycle wouldnt change = needs to take meds
- therefore EZ may not always entrain our sleep wake cycle
- idiographic study just because they show EZs cant entrain them doesnt mean others will have same result
- isolating EZs and EPs tell us little about real life
ultradian rhythm (research high internal validity)
- research done in sleep labs can manipulate variables therefore can establish cause and effect increasing scientific credibility of research
- highly controlled can control extraneous variables so high internal validity measuring what were supposed to
- so research has high internal validity and scientific credibility
ultradian rhythm (low ecological validity + low internal validity)
- sleep in sleep lab doesnt relate to real life as ppts attached to machinery affecting quaility sleep
- can act as confounding variable
- lower internal validity
- plus doesnt relate to real life so study has low ecological validity as research supports sleep in sleep labs but not real life
ultradian rhythms (individual differences)
- ultradian rhythms have significant individual differences
- found large differences between ppts esp in stages 3 & 4 of sleep
- differences are then biologically determined
- becomes difficult to make conclusions ab what normal cycles look like and what its made of
infradian rhythms (low internal validity)
- stress, diet, and exercise may influence the menstrual cycle, affecting the study’s internal validity.
- the reliability of synchronizing infradian menstrual cycles is questioned due to potential measurement inaccuracies.
- difficulty replicating results in other studies casts doubt on the reliability of findings related to infradian menstrual synchronisation.
infradian rhythms (practical application SAD)
- it has led to the development of light therapy, whereby a box giving out very strong
light is used to reset the body’s internal clock and reduces the effects of SAD in about 80% of
people. - led to this real-life
application of light therapy, which has less side effects than traditional therapies such as
antidepressants.
ERPs positives & negatives
+ high temporal and spatial resolution
+ non invasive
- difficult to detect change
- electrodes placed superificially so voltage only detects out brain activity
post mortum positives & negatives
+ allows detailed examination
- cant establish cause and effect
- ethics no consent
- no follow up
FMRIs positives & negatives
+ non invasive
+ high spatial resolution
- poor temporal resolution
- only focuses where blood delivered in brain
EEGs positives & negatives
+ used to diagnose epilepsy
+ high temporal resolution
- poor spatial
- only signals from outer part of brain
hemispheric lateralisation and split brain research (research support + low pop validity)
- sperrys research shows brain lateralised as two hemisphere specialised for different tasks
- eg right for visual spatial and left for language
- however split brain procedure done on small group of people as it is rarely done now and those who do have it have epilepsy
- so low population validity just because their brains support hemispheric lateralisation doesnt mean everyones will
hemispheric lateralisation and split brain research (low internal validity)
- each participants had different amounts of their corpus callosum cut
- so everyone experiences different amount of split brain
- therefore results found may not be internally valid as confounding as not sure if everyone has same impact of split brain
- low internal validity questions support of research to hemispheric lateralisation
hemispheric lateralisation and split brain research (differences between hemispheres overstated)
- some agree both hemispheres are specialised for different things (left for verbal right non verbal)
- many psychologists agree no clear distinction and that both sides of brain used for everyday tasks
- one side of brain can do others tasks if needed = called plasiticity as brain makes new connections
- shows brain does not show hemispheric lateralisation which goes against theory as one side of brain can do others tasks
