Brain scanning Flashcards
What is empirical method?
Experimental confirmation, exploration and debunking. Rather than proving something is wrong the alternative must be proved true.
What are behaviour empirical methods?
Self report, questionnaire, interviews, experiments and observations.
What are brain testing methods?
Hemodynamic, electrophysiological, anatomic and brain stimulation.
What are body testing methods?
Psychophysiology, heart rate and electrodermal.
What does MRI scans do and how?
Detects brain abnormalities, can scan and create images, tests structural differences in the brain all done by identifying haemodynamic blood flow.
What are the cons of MRI scans?
- Does not produce 3D image
- Low temporal resolution as has 5 second delay.
- Invasive method
- Time consuming
- Expensive
What are the pros of MRI scans?
-High spatial resolution
What is the difference between MRI and FMRI?
FMRI is an MRI scan whist the patient is undergoing cognitive tasks.
Why are FMRI’s used?
It allows the study of the function of the brain not only the structure.
How does the measurement of haemoglobin work in MRI scans?
When oxygen is transported to the brain via haemoglobin the MRI magnet detects the iron present in the deoxygenated haemoglobin molecules., when the brain is functioning the levels of deoxygenated haemoglobin are altered. Therefore the M+FMRI does not measure activity but the metabolic reaction which can be inferred.
How do PET scans work?
Radioactive tracer injected to make blood flow visible to scanner. More direct measurement of blood flow.
What are the cons of PET scans?
- Need ethical approval for injection
- Only measures blood flow whereas fMRI can measure blood density.
- Lower spatial resolution.
What are the pros of PET scans?
Higher temporal resolution.
-Movement does not disrupt as attached to the machine.
What is Donders subtraction method?
In brain scans it is the idea of doing tasks in steps in order to use subtraction to figure out each step as brain functioning. E.g. see hammer, say hammer, think hammer.
How is brain connectivity measured?
DTI which measures structural connectivity.
