Ways of investigating the brain Flashcards
FMRIs
a technique of brain scanning that uses a magnetic field and radio signals to monitor the blood flow in the brain
EEG
Measures electrical activity in the brain by detecting small changes in voltage from action potentials in the neurones.
ERP
measure the electrical activity in the brain by detecting changes in the voltage when a certain stimuli is given to the participant e.g a loud noise, a specific response in produced.
Post mortem examinations
The brain is analysed after death to determine whether certain observed behaviors during the patient’s lifetime can be linked to abnormalities in the brain.
FMRI’s - AO3
Strength - non-invasive: does not expose patient to any harmful radiation
Strength- High spatial resolution allowing us to see in detail to the millimetre.
Weakness- Poor temporal resolution there is a time lag of 5 seconds between the activity in the brain and when it is shown.
Weakness- It doesn’t necessarily represent the neural activity as the neurones are not focused on, only the areas of the brain that the blood is delivered to.
EEG - AO3
Strength- Has been required for the diagnosis of epilepsy in people, and has therefore aided treatment
Strength- Extremely high temporal resolution to the millisecond.
Weakness- Poor spatial resolution as the exact area of the neural activity can’t be pinpointed.
Weakness- We can only get signals from the outer areas of the brain as the electrodes are attached to the scalp. therefore important areas like the hippocampus do not have detected electrical activity.
ERP - AO3
Strength- Extremely high temporal resolution and spatial resolution.
Strength- non-invasive
Weakness- As specific changes are the purpose of these, it can be hard to detect them and may require more than one trial, not practical.
Weakness- The electrodes are placed superficially so they will only detect the voltage changes in the outer areas of the brain.
Post Mortem examinations - AO3
Strength - vital in our early understanding of how the brain operates
Weakness - Length of time between death/post mortem, drug treatments and age of death are confounding variables
