Electroencephalography (EEG) How It Works

Electrodes on scalp measure electrical activity in neurons. Sample Finding: Depression and anxiety linked with increased activity in right frontal lobe.

Magnetoencephalography (MEG) How It Works

Head coil records magnetic fields from brain’s electrical currents. Sample Finding: Soldiers with PTSD show stronger magnetic fields in visual cortex when viewing trauma images.

Computed Tomography (CT) How It Works

X-rays of the head show brain damage. Sample Finding: Children’s brain injuries on CT predict lower intelligence and memory performance.

Positron Emission Tomography (PET) How It Works

Tracks where radioactive glucose goes in brain during tasks. Sample Finding: Monkeys with anxious temperament show more glucose use in fear and memory regions.

Magnetic Resonance Imaging (MRI) How It Works

Uses magnetic fields and radio waves to map brain structure. Sample Finding: People with history of violence have smaller frontal lobes tied to moral judgment and self-control.

Functional MRI (fMRI) How It Works

Measures blood flow to brain regions by comparing MRI scans. Sample Finding: Plane crash survivors showed more activation in fear, memory, and visual centers when viewing trauma footage.