biopsych Flashcards
It was previously believed the brain worked ____________
Holistically
The main part of the brain is known as the ________
Cerebrum
The cerebrum is split into two hemispheres - this is known as __________
Lateralisation
How many lobes is the brain divided into?
4
Which lobe is the motor cortex located in?
Frontal
Which lobe is the visual cortex located in?
Occipital
What are the four lobes?
Frontal lobe
Parietal lobe
Occipital lobe
Temporal lobe
What is the motor cortex responsible for?
Voluntary movement
What is the somatosensory cortex responsible for?
Skin sensations
Where is the visual cortex located?
The occipital lobe
Where is the auditory cortex located?
The temporal lobe
Where is wernicke’s area located and what is it responsible for?
Left temporal lobe
Speech comprehension
Where is Broca’s area and what is it responsible for?
Left frontal lobe
Speech production
Language is concentrated (localised) to the _____ hemisphere
Left
What are two strengths of localisation?
Case study support - Phineas Gage: reinforces the idea that personality is localised to then frontal lobe as Gage experienced a post traumatic personality change after a sever head injury. It was reported Gage shifted from calm and reserved to hostile and quick tempered - adding validity to the theory of localisation and refuting the idea that the brain works holistically
Brain scans - Peterson et al: demonstrated how Broca’s area was active during a reading task and Wernicke’s area was active during a listening task (language centres responsible for speech comprehension & production) - boosts credibility/validity of localisation as it supports the idea that different areas of the brain are responsible for different functions
What are two limitations of localisation?
Counter evidence - Lashley’s rats: conducted using animals specifically rats, 10- 50% of the rats brains were removed to test how they would navigate a maze and it was found there was no one area that impacted their navigation and the rat’s ability to learn the maze was unaffected supporting the idea that the brain works holistically and diminishing the validity of localisation
Reductionist/ oversimplified - plasticity: plasticity is the concept that the brain adapts itself to recover a lost or compromised function after trauma, this is done by the surviving brain circuits adjusting to allow the same neurological action to be achieved - this implies the brain works in a holistic way as functions can be recovered in different areas of the brain - localisation is an incomplete theory diminishing the validity of it
The left hemisphere dominates the ______ side of the body
Right
The right hemisphere dominates the ____ side of the body
Left
The right hem dominates the left side of the body and the left hem dominates the right side - this is known as ___________ wiring
Contralateral
Damage to wernicke’s area leads to wernicke’s ______
Aphasia
What is experienced during wernicke’s aphasia?
Unable to understand meaning of words
Produce nonsense words in speech
Damage to Broca’s area leads to Broca’s ______
Aphasia
What is experienced during Broca’s aphasia?
Slow speech that lacks fluency
The occipital lobes are ___________
Ipsilateral
I.e. the left occipital lobe is not solely responsible for our right eye
Each eye has a right and a left _____ field
Visual
The left visual field is controlled by the _____ hemisphere
Right
The right visual field is controlled by the ____ hemisphere
Left
The idea that each hemisphere is responsible for certain functions is known as …..
Lateralisation
If the left occipital lobe is damaged the ____ visual field is impaired in both eyes
Right
Sperry’s split brain research was a _______ experiment
Quasi
What was Sperry’s sample?
11 epileptic people who had undergone a commissurotomy to treat their epilepsy compared to a control group who hadn’t had a commissurotomy
What did Sperry find?
When information was shown to their right visual field they can verbalise what they see (because it is processed in the LH where Broca’s area is)
When information is show to their left visual field they can see it but can’t verbalise it as it is processed in the RH (no Broca’s area) and the corpus colossum is severed meaning the language centres in the LH can’t be reached
What are strengths of split brain research?
Research support
It has been found that those with a split brain are better at certain cognitive tasks like spot the odd one out as they can utilise one hemisphere effectively with no interference - boosts the validity of hemispheric lateralisation
Standardised procedures - highly specialised and controlled procedures are used e.g. lab experiment with ppts shown images to both visual fields - increased validity and reliability - adds scientific credibility
What is a limitation of Sperry’s research?
Confounding variables - CG also didn’t have epilepsy - their ability to complete tasks may have been due to the lack of epilepsy instead of their intact corpus colossum - diminished validity
What is a strength of hemispheric lateralisation?
Animal studies with chickens show lateralisation is adaptive as the chickens with lateralised brains can do two things at once e.g. look for food & predators whereas unlateralised chickens can only do one - boosted validity for hemispheric lateralisation
What are two limitations of hemispheric lateralisation?
Plasticity - the brain is considered plastic because it has the ability to change & move functions after a trauma -diminishes the validity of hemispheric lateralisation - incomplete theory
Differences in functions perhaps overstated - popular psychology oversimplifies and over emphasises differences between hemispheres - each hemisphere can perform each task when and if the situation requires it - incomplete theory - lack of validity
When are post mortems conducted?
after death - first method of studying the brain
Why are post mortems conducted?
Likely conducted on those with rare circumstances/ disorders compared to a neuro typical brain e.g HM
What are two strengths of post mortems as a way of studying the brain?
first influential methods - paved the way for other methods of brain studying to be discovered
Discovery of language centres - Broca’s area (speech production) & Wernicke’s area (speech comprehension) - associated with speech and a key finding - boosted validity & effectiveness
What are two limitations of post mortems?
correlation/ not causation
Can’t say for certain any abnormalities in the brain caused certain behaviours - & theories can’t be tested as the subject is dead which means variables can’t be manipulated - lack of validity
Ethical issues i.e. obtaining consent - difficult to obtain consent from the deceased e.g HM was unable to give consent and the individual may not be in the right state of mind to be capable of giving consent
What does FMRI stand for?
Functional magnetic resonance imaging
What do FMRI’s do?
produces 3D images of active brain areas & measures haemodynamic response (blood flow & oxygenation)
What are FMRI’s used for?
used to detect where brain functions happen while carrying out a task
What are two strengths of FMRI’s as a way of studying the brain?
A safe method of studying the brain - FMRI’s are non invasive & dont involve radiation - virtually risk free
High spatial resolution - can show down to the millimetre exactly where blood flow is/ being directed - adds to the validity of FMRI’s
What are two limitations of FMRI’s as a way of studying the brain?
Expensive - using an FMRI is expensive as electromagnets require a lot of electricity - buying an FMRI is expensive too - limited applicability as it can’t be used regularly due to financial restrictions
Poor temporal resolution - works 5 seconds behind real time and so can’t tell exactly when brain functions happen
What does EEG stand for?
Electroencephalogram
What do EEG’S do?
Detects electrical activity i.e. action potentials across the cortex or specifically abnormal patterns e.g. epilepsy
What are 3 strengths of EEG’s as a way of studying the brain?
A safe & cheap method - non invasive & cheaper than FMRI’s also virtually risk free
High temporal resolution - no delay - to the millisecond of transmission - preciseness boosts validity
Practical application - EEG’s have been used to diagnose epilepsy and sleep disorders (measures brainwaves whilst people sleep) - prove effectiveness/usefulness - boosted validity/ credibility
What does ERP stand for?
event related potential
What do ERP’s do?
detect brain activity in relation to a specific stimulus