EEG and MEG

Electrical measures encompass techniques that record brain activity directly, through scalp-surface detection of electrical and magnetic signals emitted by the brain. Electrical signals are the literal mechanism through which the brain communicates and synchronizes activity across different anatomical regions.  Electrical measurement techniques thus provide the most direct measures of cognitive processing, and are the only measures that record brain activity at the speed of cognition - that is, in milliseconds rather than seconds.

The two most commmonly used electrical measurement techniques are:

• Electroencephalography (EEG)
• Magnetoencephalography (MEG)