ways of investigating the brain Flashcards
spatial resoulation
level of accuracy in identifying the exact location of the brain sturcure in space (where it happened
temporal resolution
level of accuracy in idenfying exact location of brain sturcture in time (when it happened)
FMRI
works by detacting changes in blood oxygnation adn blood flow
when brain more active, requires more oxygen
demand for oxygnated vlood is directed twoards area most actibe
known as the haemodynamic response
porcues 3d activity maps which show where teh oxygnated blood is flowing in brain and where it is most concetrated
strength of FMRI
good spatial resolution. pictures we recive provides details to the milimetre and therefore provides clear picture
virtually risk free straightforward to use and non invasive
weakness of FMRI
expensive and can only capture good picture is erson is completely still
look at blood flow in brain but not neurons therefore less epcific insight of brain
EEG
measures electrical avcivity
via electrodes are attached to individuals scalp using skull cap
scan recording represent brainwave patterns
often used as diagnostic tool
strength of EEG
usefuul for diagnosing eocnditions e.g epliepsy
high temporal ersloution as can detect brain activity within millisecond
weakness of EEG
poor spatial resolution as canoot pinpoint exct location of neurjn activuty
signals can also be missed
ERP
more specific eeg recording
by eliminating extraneousneuroal acitvty and taking statisfical avergae of data
strength of ERP
more specifc than EEGS, good temporal resoultion, have clear idea of time neural acitity took place
weakness of ERP
establish pure data =, background noise and externeous variabes must be eliminated whcih is not always easy to achieve
post-mortems
involves looking at a person brain after a persons death
those who are used have rare disroders or experinced unusal deficits in their lifetime
areas of damge are examined after death
may also compare with control brain (brain where person suffered with no deficits)
strength of post mortems
provided foundation for understanding of processes within the brain
e.g paul broac and karl wernicke relied on this to establish links betweeen the brain behaviour and language
weakness of post mortems
ethical issues as informed cnstn cannot always be given by the patient before their detah
e.g HM was unable to give his consent
however, reserach was still done on his brain after death
