Biopsychology- Ways Of Investigating The Brain Flashcards
Functional magnetic resonance imaging (MRI) -
A method used to measure brain activity while a person is performing a task that uses MRI technology (detecting radio waves from changing magnetic fields). This enables researchers to detect which regions of the brain are rich in oxygen and thus are active.
Electroencephalogram (EEG) -
A record of the tiny electrical impulses produced by the brain’s activity. By measuring characteristic wave patterns, the EEG can help diagnose certain conditions of the brain.
Event-related potentials (ERPs) -
The brain’s electrophysiological response to a specific sensory, cognitive, or motor event can be isolated through statistical analysis of EEG data.
Post-mortem examinations -
The brain is analysed after death to determine whether certain observed behaviours during the patient’s lifetime can be linked to abnormalities in the brain.
How does functional magnetic resonance imaging (fMRI) work?
fMRI detects changes in blood oxygenation and flow resulting from neural activity. Increased activity in a brain area leads to increased oxygen demand and blood flow (haemodynamic response).
What does fMRI produce, and why is it important?
fMRI produces 3D activation maps, showing brain areas involved in specific mental processes, aiding understanding of localisation of function.
What does an electroencephalogram (EEG) measure?
EEG measures electrical activity in the brain via electrodes on the scalp, recording brainwave patterns from millions of neurons.
How is EEG used as a diagnostic tool?
EEG helps detect unusual arrhythmic brain activity patterns, which may indicate epilepsy, tumors, or sleep disorders.
What are event-related potentials (ERPs)?
ERPs are brainwave responses linked to specific sensory, cognitive, or motor events, derived from EEG recordings by filtering out extraneous activity.
What can post-mortem examinations reveal?
They analyze brain damage after death to identify causes of rare disorders and deficits, often comparing with neurotypical brains.
What are the strengths of fMRI?
Non-invasive and risk-free.
High spatial resolution (detailed by the millimeter).
Provides clear localisation of brain activity.
What are the weaknesses of fMRI?
Expensive.
Requires participants to stay perfectly still.
Poor temporal resolution (5-second lag).
Measures blood flow, not individual neuron activity.
What are the strengths of EEG?
Useful for diagnosing epilepsy and understanding sleep stages.Extremely high temporal resolution (milliseconds).
What is a weakness of EEG?
It provides generalized data and cannot pinpoint exact neural activity sources or distinguish between adjacent brain regions.
How do ERPs improve upon EEG?
ERPs add specificity to EEG measurements, offering precise insights into cognitive processes with excellent temporal resolution.
What is a weakness of ERPs?
Lack of standardisation between studies and challenges in eliminating background noise can affect data reliability.
What are the strengths of post-mitten studies?
Essential for early understanding of brain functions (e.g., Broca and Wernicke).
Improves medical knowledge and generates hypotheses.
What are the weaknesses of post-mortem studies?
Causation issues: damage observed may be unrelated to deficits
Ethical concerns: individuals may not give informed consent before death (e.g., HM).
