Ways of Studying the Brain Flashcards
techniques of investigating brian often used for
medical purposes in diagnosis of illness
what is the purpose of scanning in psycho redearch
investigate localisation (investigate what part sof brain do waht )
FMRI stands for
Functional Magnetic Resonance Imaging
fmri work
by detecting changes in ….
in blood oxygenation flow
and flow that occurs as a result of the neural activity
in specific parts of the brain
neural meaning
brain
what happens when a brain area is more active
consumes more o2 and to meet this demand increased blood flow is directed to the active area
(haemodynamic response)
fmris porduce
3d images (activition maps )
activation maps( fmris) produce show which part…
this has important implications for our understanding of…
of brain involved in particular mental processes
understanding of localisation of functino
outline 2 strngth of fmri
unlike other scan tech like PET
dont rely on use of radiation if admin done properly its virtually risk free, non invasive and straightforward to use
also produces images with very high spatial resolution, depicitng detail by the mm and providing a clear pic of how brain activity is localised
this means fmris can safely provide a clear pic of brain activity
FMRI LIMITATION -
can only measure bloodflows , it cannot hone in on the activity of individual neurons and so it can be difficult to tell exactly what kind of activity is being shown on the screen
this means its not a truly quantitiative measure of mentla activity in these brain areas
EEG stands for
electroencephalogram
EEGS measure
leccy cactivity wihtin brain
how do eegs emasure leccy activity within the brain
via electrodes that are fixed to an indis scalp using a skull cap
EEGS- what does scan recording represent
brainwave patterns
generated from action of ks of neurons ,
providing an overall account of brain activity
EEGS- often used by …
clinicians
EEGS- how does clinicians use EEGs
as a diagnostics tool
EEGS- why do clinicians use EEGS as a diagnostic tool
becasue arrhythmic patterns of activity may indicate neurological abnormailities such as epilepsy , tumors or sleep disorder
EEGS- what is a arrhythmic pattern
no particular rhtm
Event Related Potential - Although EEG has many scientific and clinical applications in its raw form it is a
crude and overly general measure of brain activity
Event Related Potential - However within EEG data what is contained
all neural responses associated with specific sensory
cognitive
and motor events that may be of interest to cognitiv neuroscientists
Event Related Potential - becasue EEGs contain neural respones associatesd with specific x events what have researchers developed
a way of teasing out and isolating neural respones
Event Related Potential - how have researchers developed a way of teasing out and siolating the neural repsonses
using a statstical avg technique
Event Related Potential - how does the stastical asvg tech work
all extraneoys brain activity from og EEGs recording is fitered out leaving only responses relevant to for example e.g presentaiton of specific stimulus or performance of specfic tasj
Event Related Potential - what remains after the statistical avg test
ERPs
Event Related Potential - what are they
types of brainwaves triggerd by particular events
Event Related Potential - what has research revealed about ERPs
there are many different forms
how e.g they are linked to cog processes such as attention and perception
POST MORTEM EXAMINATIONS - what is this
technique involving analysis of person brain following their death
POST MORTEM EXAMINATIONS - in psych research what typeof indis are brains are subject to a PME
likely to be those of
have a rare disorder and have xp unusual deficits in cog processes
or behaviour in theri lifetime
POST MORTEM EXAMINATIONS - what are examined after death
areas of dmage within the brain
POST MORTEM EXAMINATIONS - why are areas of teh brain examined after death
as means of establishing likely cause of the affliction the person experienced
POST MORTEM EXAMINATIONS - examining areas of damage within the brain may also involve
comparison with a neurotypical brain to understand the extent of the difference
STRENGTH EEG - useful in clinical diagnoses
useful in clincal diagnoses of conditions e.g epilepsy
as record abnormal neural activity that can be associated with eplieptic seizures ( as random bursts of activity)
this cna help determine whether someone xp seizure has epilepsy or alt condition
EEG LIMITATION - spatial resolution
poor spatioal resolution
EEGs only provide generalised info
leccy activity can be picked up by several neighbouring electrodes
mkaing source of any activity difficult to pinpoint
therefore researchers uable to distinguish between activities originating in diff but neighbouring location in brain
ERP strength - specificty
limitations of EEG partly addressed through use of ERPs
bring about increased specifity to measuremnt of neural processes than could ever be achieved use raw EEG data
ERP strenght - temporal resolution
as derived from EEP measurements have high temporal resolution
esp when copared to neuroimagin techs sucha s FMRIS
therfore ERPs reg used to measure cog functions and deficits such as allocation of attentional resources and maintenance fo working memory
ERP limitation - small and difficult to pick up
ERPs are very small and foten difficult ot pick up from the other electrical actiivty in the brian
this means a large number of trials often have to be conducted in order to gain meaningful data - which costs money and takes a lot of time -
also limits types of q erp can ralistially answer - so only useful for certian things
POSTMORTEM STRENGTH - DETAIL
Allow for more detailed examination of anatomical and neurochemical elemts of brian
which woudlnt be possible with less invasive methods like fMRIs and EEGs
meaning we can explore regions of brian that wouild otehrwise be unacccesible
POSTMORTEN STRENGHT(as a result od the detail point) - understandign
have deepened understanding of certain disorders such as s chizo
as provded evidence for structural anomalies and changes to neurot systems both assocuiated with schizo
POSTMORTEM LIMTATION - CV
people die in variety of circum & at avrying stages of disease , both whic cna influence the post mortem brian
drug treatments , age of death , tim between death and PM can act as confounding variables
so observed damage to teh brian may not be linked or may paint an incorrect pciture of behaviour under review
