Knowt
WAYS OF STUDYING THE BRAIN
~Functional Magnetic Resonance Imaging (fMRI)~
A technique for measuring changes in brain activity
When a brain area is more active, it consumes more oxygen
To meet this increased demand for oxygen, blood flow is directed towards the active area of the brain (this is known as the haemodynamic response)
fMRI produces 3-D images called activation maps
These maps shows which parts of the brain are active while an individual performs a task
fMRI therefore has important implications for our understanding of localisation of function
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~Electroencephalogram (EEG)~
Measures electrical activity within the brain
Electrical activity is measured via electrodes which are fixed to an individual’s scalp
These detect small electric signals resulting from the activity of neurons within the brain
These electrical signals are graphed over a period of time, creating an EEG
EEG’s are often used as a diagnostic tool by clinicians
Unusual arrhythmic patterns of activity may indicate a brain disorder such as epilepsy or Alzheimer’s disease
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~Event-Related Potentials (ERP’s)~
Uses electrodes attached to the scalp
A stimulus (e.g. picture or sound) is presented to the participant
Researchers focus on brain activity related to the stimulus
ERP’s require separation from background EEG data
Stimulus is presented multiple times (usually hundreds)
Responses are averaged to reduce extraneous neural activity
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~Post-Mortem Examination~
Analysis of an individual’s brain after death
They can be used to determine whether certain observed behaviours during the individual’s lifetime can be linked to abnormalities in the brain
In psychological research, individual’s whose brains are subject to a post-mortem are likely to be those who have a rare disorder and have experienced unusual deficits in mental processes or behaviour during their lifetime
Their brain may be compared to a neurotypical brain in order to ascertain the extent of the difference
