ways of studying the brain Flashcards
what are the three ways of studying the brain?
-functional magnetic resonance imagine (fMRI)
-electroencephalogram (EEG) and event-related potentials (ERPs)
-post-mortem examinations
wat are fMRIs?
ways of studying the brain using a magnetic field and radio signals to monitor blood flow in the brain, to produce a moving image of brain activity
how do fMRIs work?
-measures the energy released by haemoglobin (when it has oxygen it reacts differently to when it doesn’t)
-so when an area of the brain is active, it uses more oxygen, and the difference in the amount of energy released by haemoglobin is measured by the scanner and the change is recorded
-shows activity within a second of it occurring
-accurate to within 1-2mm of the brain
research on fMRIs
-beevers et al 2010 - used fMRI to find that people with depression had difficult activating brain areas associated with cognitive control of emotional info
evaluate fMRIs
-provides a moving picture (so patterns can be examined rather than just physiology)
-complexity of the brain means interpreting fMRIs is problematic
-fMRI machines are expensive and require trained operators
-sample size in studies is often small due to limited availability and funding, making results less generalisable
what is electroencephalogram (EEG) and event-related potentials (ERP)
EEG - electrode placed on the scalp to record electrical brain activity of the brain, can be over a hundred electrodes, measures the immediate activity of the cells under the electrode
ERP - uses the same apparatus as EEGs but records activity in response to a certain stimuli
research on EEG and ERP
-costa et al 2013 - females said they wouldn’t get aroused by nude male pictures, but ERPs showed arousal, showing they have more accuracy than self-reports
evaluate EEG and ERP
-only reasonable accurate, finer detail is missed, only suitable for certain research
-cheaper methods of scanning
-output of the equipment needs to be interpreted so requires a level of expertise
-ERP useful to test self-report answers, also good for socially sensitive topics and topics open to social desirability bias
what are post-mortem examinations
-when a persons body is examined after they have died
-can be used to see where damage had occurred and how it might explain behaviour exhibited prior to death
research on post-mortem examinations
-domanski 2013 - broca performed a post-mortem on a patient to find the Broca’s area responsible for the production of speech
evaluate post-mortem examinations
-no brain activity measured
-issue with comparison to functioning prior to death (may have little info from alive)
-some brains may have been affected by the reason for death
-no discomfort of the person as they’re not alive
