Ways Of Studying The Brain Flashcards
What are the four ways of studying the brain?
-fMRI.
-EEG.
-ERP.
-Post-mortem examination.
What are the non-invasive methods of studying the brain?
-fMRI.
-EEG.
-ERP.
What is the invasive method of studying the brain?
-Post-mortem examination.
What is spatial resolution?
Identification of where brain activity took place.
What is temporal resolution?
Identification of when a brain activity took place.
What is fMRI?
3D scans using magnetic & radio waves track haemoglobin blood flow in the brain. Active areas (oxygenated blood) can be compared with areas that are lower in activity (deoxygenated blood) and can be shown on the fMRI image.
Evaluation points for fMRI:
+Good spatial resolution of 1mm (helps identify localisation).
-Expensive (NHS costs, small sample size of machines).
-Participant needs to remain still throughout the 45 minute procedure.
-Poor temporal resolution - 5 second delay, capturing brain activity that isn’t live (e.g. trying to find a reaction to a picture of a dog: with a 5 second delay, it will be impossible to capture the live reaction).
What is EEG?
Electrodes (flat metal discs) are placed on the scalp, picking up neuronal activity from the brain over a period of time, sending the information to an EEG machine.
What does the EEG show?
-Amplitude: size/intensity of activity.
-Frequency: speed of activity.
What are the EEG wavelengths?
-Alpha.
-Beta.
-Gamma.
-Theta.
What is ERP?
Measures the brain’s response to a stimulus using EEG apparatus & technique. The stimulus is presented many times and a statistical average response is graphed.
Waves generated during the ERP:
-‘< 100 milliseconds’: sensory.
-‘> 100 milliseconds’: cognitive.
Evaluation points for EEG & ERP:
+Cheaper than fMRI.
+Tests reliability on self-report techniques.
+Good temporal resolution (detects disorders that affect brain activity, like Alzheimer’s disease, epilepsy, and sleep disorders).
-Poor spatial resolution (electrodes only measure brain activity for cells directly below).
What is post-mortem examination?
An examination of the corpse where the brain is examined to correlate structural abnormalities to behavioural deficits (e.g. Broca’s area).
Evaluation points for post-mortem examination:
+Aids us in understanding localisation of function (e.g. Broca’s area).
-No brain activity can be measured as the person is DEAD.
-Difficult to compare the brain after death with prior functioning, as neuronal changes may be due to death: any relationship found would be correlational.
