Activation qEEG and Biofeedback Therapy

Basic qEEG Concepts

The quantitative EEG (qEEG) is a digital analysis of the classical EEG analog tracings which neurologists have employed for seizure detection. the following figure shows a typical EEG record.

Quantitative EEG


The qEEG, however, is not appropriately used in the detection of seizure activity. The EEG analog signal is digitized and the information saved to a hard disk. Once the data has been saved to a permanent record, it then becomes possible to develop concepts, conduct statistical analysis on the wave forms and compare individuals to a normative databases on the selected variables. The wave forms are analyzed according to a period of time, called an epoch, and the waves that have occurred during that time period are analyzed. Historically, the frequencies have been divided into 5 groups: Delta (0-4 Hertz); Theta (4-8 Hertz); Alpha (8-13 Hertz); Beta (13-32 Hertz); and gamma (32-64 Hertz). The following figure visually presents how these frequencies will appear on an qEEG recording.


There has been a nomenclature developed to indicate the locations where the sensors are placed on the scalp. This figure presents the nomenclature.

The head figure image is presented from above. The subject’s nose is above, the left ear on the left and the right ear on the right. The letter F stands for frontal; T for temporal; C for central; P for parietal and O for occipital. Odd numbers represent locations in the left hemisphere and even numbers for the right hemisphere.


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