Ways to Study the Brain

Question 1

CAT (Computerized Axial Tomography) Scans (CT scan)

Answer 1

• X-rays to create image of the brain (tumor/abnormal swelling/bleeding…but it can’t tell us anything about what areas of the brain are active in a given time.)

Question 2

MRI (Magnetic Resonance Imaging)

Answer 2

• This method uses radio waves and they are exposed to a magnetic field.
• The radio waves are then added to the magnetic field and disrupts orientation of atoms.
• As atoms move back to alignment with magnetic field they release signals and those are used to create image.
• This also doesn’t tell us anything about brain function either.

Question 3

EEG (Electroencephalogram)

Answer 3

• External, can’t tell us about activity of individual/groups of neurons.
• Can only look at sum total.
• Can tell us about seizures, sleep stage, cognitive tasks. Not invasive!

Question 4

MEG (Megnetoencephalogram)

Answer 4

• Records the magnetic fields produced by electric currents in the brain.

Question 5

fMRI (functional Magnetic Resonance Imaging)

Answer 5

• same image from MRI but can look at which structures are active!
• Neurons that are active require oxygen.
• Measuring relative amounts of oxygenated vs deoxygenated blood in the brain.
• Acronym: f =functional = tells us function about specific region of brain

Question 6

PET (Positron Emission Tomography) Scans

Answer 6

• Inject glucose into cells and see what areas of brain are more active at given point in time.
• Active cells = use most glucose
• Acronym: PETs like glucose