Brain imaging techniques
Electroencephalography (EEG) is a non-invasive method of measuring the electrical activity of the brain by recording electrical potentials from the surface of the head using electrodes placed on the scalp. EEG is one of only two techniques currently available (the other being magnetoencephalopgraphy, or MEG) that allow us to measure the activity of the brain in real time, on a millisecond by millisecond basis, in awake people.
Functional magnetic resonance imaging (fMRI)
Magnetic resonance imaging (MRI) is a method of imaging the brain using a strong magnetic field and radio waves. Functional magnetic resonance imaging (fMRI) is a type of MRI that produces images of brain activity by measuring changes in blood oxygen level that occur in areas of the brain which are active.
Positron emission tomography (PET)
Positron emission tomography (PET) is a method of imaging brain activity that uses radioactively-labelled tracer compounds whose distribution in the brain can be detected, thus revealing which areas of the brain are actiive.