Brain Scans

Trepanation

process of relieving pressure on the brain, prehistoric times

EEG (Electroencephalogram)

electrodes record electrical brain activity

Alpha waves

Related to relaxation and attention, present when awake with eyes closed

Beta waves

Awake, eyes closed or open, influenced by drugs

Theta Waves

Sleep, not obvious for awake adults

Delta Waves

Deep sleep

PET (positron emission tomography)

injected radioactive glucose reveals the metabolic or biochemical function of tissues and organs

CAT (computerized tomography)

layered xrays, radiation, 3D imaging, complex structures

MRI (magnetic resonance imaging)

3D, no radiation, better for tissue

fMRI (Functional Magnetic Resonance Imaging)

Tracks blood flow in the brain to show real-time activity

Case Studies

In-depth investigations, unique brain-behavior relationship insights, major breakthroughs in neuroscience

Phineas Gage

Rod through frontal lobe, personality change

Henry Molaison

hippocampus removed to treat epilepsy, couldn’t form new memories