Ways of studying the brain Flashcards
how do psychologist investigate brain localisation
medical techniques
what is the purpose of scanning in psychological research
often to investigate localisation - to determine which parts of the brain do what
what does the FMRI scan
highlights active areas of the brain
what happens during FMRI scan
it detects changes in the both blood oxygenaton and flow that occur due to neural activity in specific brain areas
what is haemodynamic response
when a barin area is more active it consumes more oxygen and blood flow is directed to the active area
what do FMRI produce
3D image showing which parts of the brain are more active and therefore must be involved in particular mental processes
what does EEG scan show
overall electrical activity
what does the EEG scan do
measures electrical activity within the brain via elctrodes using a skull cap
what does the scan recording represent
the brainwave pattern generated from the thousands of neurons. this shows overall brain activity
what is EEG used for
diagnostic tool. for example unusual arrhythmic patterns of brain activity may indicate abnormalities such as epilepsy, tumours or sleep disorders
what are ERPs
what is left when all extraneous brain activity from an EEG recording is filtered out. And ERPs are type of brainwaves that are triggered by particular events
how is ERP used
using statistical technique, leaving only those response that relate to the presentation of a specific stimulus
what has research revealed about ERP
many different forms of ERP and how these are linked to cognitive processes
what is a port mortem examinations
a technique involving the analysis of a persons brain following their death
what happens during a postmortem examinations
areas of the brain are examined to establish the likely cause of a deficit or disorder that the person experienced in life
This may be also involve comparison with neurotypical brain in order assesses the extent of the different
What are Strengthd of FMRI
risk spatial and high spatial resolution
Unlike other scanning techniques (e.g PET), FMRI does not rely on the use of radiation and is safe .
It also produces images with high spatial resolution showing detail by the millimetre.
This means FMRI can safely provide a clear picture of how brain activity is localised
what is Limitation of FMRI
expensive and poor temporal resolution
FMRI is expensive compared to other techniques
It has poor temporal resolution because of 5-second lag between initial neural activity and image. This mean FMRI may not truly represent moment to moment brain activity
What are the Strength of EEG
EEG has contributed to our understanding of the stages of sleep.
It has high temporal resolution- brain activity in one millisecond
this shows the real world usefulness of the technique
what are the Limitations of EEG
the EEG produces a generalised signal from thousands of neurons.
Its difficult to know the exact source of neural activity
Therefore EEG cant distinguish the activity of different but adjacent neurons
what are Strengths of ERP
Measures of neural processes more specific with ERPs and EEGs
ERPs have excellent temporal resolution better than FMRI
This means that ERPs are frequently used in cognitive research
what are Limitations of ERP
lack of standardisation makes it difficult to confirm findings in studies involving ERPs
Background noise and extraneous material must be completely eliminated. These issues are a problem because they may not always be easy achieve
what are strengths of post mortems
Broca and Wernicke both replied on post- mortem studies
used to link HM’s memory deficits to damage in his brain
This means they continue to provide useful information
what are limitations of post mortem
observed damage in the brain may not be linked to the defects under review
Poat modern studies raise ethical issues of consent after death (e,g HM) This challenges their usefulness in psychological research
