Biopsychology Flashcards
What are two strengths of localisation of function in the brain?
- Evidence from neurosurgery- isolating the cingulate gyrus (cingulotomy) improves OCD in 30% of people with OCD (Dougherty et al)
- Evidence from brain scans- Broca’s and Wernicke’s areas (Petersen et al), semantic and episodic areas (Tulving et al)
What is the counterpoint to evidence from brain scans for localisation of function in the brain?
Learning in rats is holistic not localised (Lashley)
What is one limitation of localisation of function in the brain?
Language localisation questioned- multiple pathways (eg. right hemisphere and thalamus), not just Broca’s and Wernicke’s (Dick and Tremblay)
What is one strength of hemispheric lateralisation?
Lateralisation in the normal brain- global elements processed by RH and finer detail by LH
What is one limitation of hemispheric lateralisation?
One brain- certain hemispheres dedicated to certain tasks but no dominant RH or LH, eg. no ‘scientists brain’ (Nielson et al)
What is one strength of split-brain research?
Research support- split-brain participants faster at some LH tasks (Luck et al) because normally slowed down by inferior RH (Kingstone et al)
What is one limitation of split-brain research?
Generalisation issues- epilepsy is a confounding variable when comparing to ‘normal’ controls
What is one limitation of plasticity?
Negative consequences- plasticity not always beneficial (phantom limb syndrome, Medina et al)
What is one strength of plasticity?
Plasticity continues throughout lifespan, eg. golf training reduced neural activity in over 40s (Bezzola et al)
What is one strength of functional recovery?
Real-world application- knowledge of axonal growth leads to eg. constraint-induced movement therapy (massed practice with affected arm, restrain unaffected arm)
What is one limitation of functional recovery?
Cognitive reserve- 40% recovery for people with 16 years’ education (more cognitive reserve), 10% for less than 12 years’ education (Schneider et al)
What are four strengths of fMRIs?
- Risk-free
- Non-invasive
- No radiation
- High spatial resolution
What are two limitations of fMRIs?
- Expensive
- Poor temporal resolution
What are two strengths of EEGs?
- Helped research on sleep waves
- Temporal resolution (1 millisecond)
What is one limitations of EEGs?
Signal comes from thousands of neurons so can’t identify source
What are two strengths of ERPs?
- More specific than raw EEG data
- Higher temporal resolution than fMRI
What are two limitations of ERPs?
- No standardised procedures
- Background ‘noise’
What is one strength of post-mortem examinations?
Contributed to early research (eg. Broca)
What are two limitations of post-mortem examinations?
- Causation is an issue
- Ethical issues over consent (eg. HM)
What are two strengths of circadian rhythms?
- Shift work- reduced concentration at 6am, more accidents (Boivin et al), heart disease three times more likely (Knutsson)
- Medical treatment- chronotherapeutics, timing of drugs eg. aspirin at night to reduce heart attacks (Bonten et al)
What is the counterpoint to shift work for circadian rhythms?
Studies are correlational, effects may be disrupted social routines (Solomon)
What is one limitation of circadian rhythms?
Individual differences- cycle lengths vary (13 to 65 hours, Czeisler et al), ‘larks’ and ‘owls’ (Duffy et al), generalisations may be meaningless
What is one strength of infradian rhythms?
Evolutionary basis- synchronisation may have an adaptive function, leads to shared care for babies
What is one limitation of infradian rhythms?
Methodological limitations- many factors affect menstrual cycle, so synchronisation may occur by chance (Trevathan et al)
What is one strength of ultradian rhythms?
Improved understanding- reduced slow wave sleep in old age explains ageing effects (van Cauter et al)
What is one limitation of ultradian rhythms?
Individual differences- variation found in duration of sleep stages, especially 3 and 4 (Tucker et al)
What are two limitations of endogenous pacemakers?
- Beyond the master clock- peripheral oscillators, eg. circadian rhythm of liver cells in mice altered but SCN unaffected (Damiola et al)
- Interactionist system- research looks at pacemakers/zeitgebers in isolation, doesn’t represent real life
What are two limitations of exogenous zeitgebers?
- Environmental observations- Innuits not affected by EZs (live in darkness in summer and little light in winter)
- Case study- man blind from birth with sleep/wake cycle of 24.9 hours, could not adjust despite social cues (Miles et al)
