Ways of Studying the Brain Flashcards
What are fMRI’s
Functional Magnetic Resonance Imaging
3D images that detect changes in blood oxygenation and flow occurring due to neural activity
When the brain area is more active it consumes more blood and oxygen which shows what parts of the brain are active during mental processing
What are the strengths of fMRI’s
does not reply on radiation and if used correctly it is risk-free, non-invasive and straightforward
produced images that have very high spatial resolution (very detailed and clear picture of how brain activity is localised)
fMRI’s can safely provide a clear picture of brain activity
What are the weaknesses of fMRI’s
expensive compared to other neuro-imaging techniques
poor temporal resolution meaning there is a 5-second time lag between the image on screen and the initial firing of neural activity
means fMRI may not present moment-to-moment brain activity
What are EEG’s
Electroencephalogram
measure electrical activity within the brain via electrodes fixed to an individual’s scalp using a skull cap
the scan recording represents brainwave patterns generated from action of thousands of neurons, providing an overall account of brain activity
often used by clinicians as a diagnostic tool for arrythmic patterns of activity which may indicate abnormalities (eg epilepsy)
What are the strengths of EEG’s
useful in studying the stages of sleep and diagnosis of conditions like epilepsy (random bursts of brain activity that can be easily detected)
has high temporal resolution and can accurately detect brain activity at a resolution of a single millisecond
shows real-world usefulness
What are the weaknesses of EEG’s
the information received is very generalised rather than specific
cannot pinpoint the exact source of neural activity so researchers cannot distinguish between activities
What are ERP’s
Event Related Potentials
used statistical averaging to filter out all extraneous brain activity from the original EEG recording; this leaves responses that relate to the presentation of specific stimuli/specific tasks
types of brain waves triggered by events linked to cognitive processing
What are strengths of ERP’s
bring much more specificity to the measurement of neural processing than EEG’s could ever achieve
as they are derived from EEG measurements they have good temporal resolution
so frequently used to measure cognitive functions and deficits
What are the weaknesses of ERP’s
lack of standardisation in ERP methodology between different research studies makes it hard to confirm findings
in order to establish pure data in ERP studies, any extraneous material must be completely eliminated which is not always easy to achieve
What are post mortem examinations
analysis of a persons brain after their death to establish cause and effect
likely to be conducted on those who had a rare disorder or had experiences unusual deficits in cognitive processes or behaviour during their life
may compare brain with a neurotypical brain in order to view differences
What are the strengths of Post Mortem examinations
provided a foundation for the understanding of key processes in the brain
used by Broca and Wernicke to establish links between language brain and behaviour before neuro-imaging techniques were accessible
used to study HM to identify area of damage
means it continues to provide useful info
What are the weaknesses of Post mortem examinations
issue of causation; observed damage may not be due to the deficits under review but to other unrelated trauma
raises ethical issues as individual may not be able to provide informed consent (eg HM)
