Biopsychology - Ways of studying the brain Flashcards
Functional magnetic resonance imaging (fMRI)
Works by detecting the changes in blood oxygenation that occur as a result of neural (brain) activity in specific parts of the brain
fMRI strengths
High spatial resolution (depicting detail by the millimetre and provided a clear picture of how brain activity is localised
Virtually risk-free, non-invasive and straightforward to use as does not rely on the use of radiation
fMRI weaknesses
Poor temporal resolution - there is a 5 second time-lag between the image on the screen and initial firing of neural activity
Expensive compared to other neuroimaging techniques
Can only capture a clear image if the person stays perfectly still
Electroencephalogram (EEGs)
EEGs measure electrical activity through brainwave patterns within the brain via electrodes
Used as a diagnostic tool of unusual patterns of activity which may indicate neurological anomalies such as epilepsy, tumours or sleep disorders
EEGs strengths
EEG has proved invaluable in the diagnosis of condition such as epilepsy (a disorder characterised by random bursts of activity in the brain that can be detected on screen)
It has contributed to our understanding of stages involved in sleep (ultradian rhythms)
High temporal resolution as they can detect brain activity at a resolution of of a single millisecond
EEGs weaknesses
Poor spatial resolution: The EEG signal is not useful in pinpointing the exact source of neural activity
Event-related potentials (ERPs)
Measures brain response that is the direct result of a specific sensory, cognitive, or motor event (stimulus)
ERPs strength
Spatial resolution - bring more specificity to the measurement of neural processes that could not be achieved using raw EEG data
ERPs weakness
In order to establish pure data, background noise needs to be completely eliminated which isn’t easy to achieve
Post-mortem examinations
Analysis of a person’s brain following their death
Most likely to subject the brains of individuals with rare disorders or who have experienced unusual deficits in the mental processes
May involve comparison with a neurotypical brain
Post-mortem strength
Post-mortem evidence was vital in providing a foundation for early understanding e.g. Broca and Wernick relied on post-mortem studies in establishing links between language, brain and behaviour before neuroimaging
Post-mortem weakness
Raise ethical issues of consent from individuals before death e.g. case of HM who lost the ability to form memories and was not able to provide consent even though post-mortem research has been conducted on his brain
