Definitions for EEG – EEG Questions And Answers

Electroencephalogram correct answer: An instrument that generates a record of the electrical activity of the brain by measuring electric potentials using electrodes attached to the scalp. Electroencephalograph correct answer: A chart of the brain waves picked up by the electrodes placed on the scalp. 10-20 System correct answer: A system of electrode application on the scalp using identifiable skull landmarks as reference. Distributed using percentages of 10 and 20. Montage correct answer: The particular arrangement by which a number of derivations are displayed simultaneously in an EEG record. Bipolar Montage correct answer: Chains of derivations that consist of electrodes along the same array, where input 2 in one channels in input 1 in the next. Transverse Montage correct answer: A montage consisting of derivations from pairs along coronal (transverse) arrays. Also called a Coronal Bipolar Montage. Longitudinal Montage correct answer: A montage consisting of derivations from pairs of electrodes along longitudinal, usually anterior to posterior, arrays. Reference Montage correct answer: An arrangement of derivations in which one input 2 is common to all channels. Derivation correct answer: A pair of electrodes recorded in the EEG. Polarity correct answer: The sign of potential different between an electrode affected by the given potential and another electrode.