4 - Research Methods Flashcards
“Different regions of the brain perform different functions and are associated with different behaviours” is a key assumption of..?
Phrenology
What is the practice of pathology?
Studying someone’s brain posthumously
Which crevice present in typical brains was missing in Einstein’s?
Sylvian Fissure
Around what time was the study of a living human brain using imaging methods produced?
Early 1970s
How does a CT scan work?
Shows a structural brain anatomy by injecting a dye into the blood which increases contrast image when x-rays are passed through the brain and compiles a 3D image
What are CT scans extremely useful for?
Showing precise location or extent of damage or abnormalities in the brain
What is the main disadvantage of CT scans?
Radiation, possible link between CT scans in childhood and later brain tumours
How does an MRI scan work?
Uses harmless magnetic fields and radio waves to vibrate hydrogen atoms in the brain’s neurons, different brain strcutrues respond in slightly different ways when stimulated and these vibrations are detected by a huge magnet surrounding the person
What are MRI scans extremely useful for?
Determining brain damage or abnormalities in particular brain areas (better than CT)
Are MRI scans high or low spatial resolution?
High (1-2mm)
What are the two main disadvantages of MRI scans?
Low temporal resolution, and can’t be used by people who have internal metallic devices
What is an EEG
Functional method of brain sacan that records electrical activity in the brain through electrodes placed on the scalp (delta, theta, aloha, beta, gamma)
What are ERPs?
Measured by EEG averaged over time
What is topography vs tomography?
Topography is projecting a sensory surface, tomography is looking at slices of the rbrain
Does EEG use topography or tomography?
Topography
What are the major advantages of EEG?
Cheap, can be used for a long time, high temporal resolution (1msec)
What are the major disadvantages of EG?
Signal can be contaminated by artifacts, we can;t be sure which brain areas are active because of low spatial resolution
What is positron emission topography?
A method of functional brain imaging which moinotrs blood flow around the brain by injecting Pp with radioactive tracer which releases a positron which collies with an electron in the brain, producing photons which can be detected by a machine. The most active brain areas have the highest ocncentration of the tracer
What are the major advantages of PET scans?
Detailed images of brain function during a task, even more sensitive than CT and MRI, moderate spatial resolution
What aare the major disadvantages of PET scans?
Invasive, low temporal resolution (30 seconds per scan), limited number of scans per sossion
