Gregory J. de Montfort in Association with
Learning Discoveries Psychological Services
Telephone and Facsimile:
Quantitative Electroencephalograph (QEEG)
What is a Quantitative Electroencephalograph?
Quantitative Electroencephalograph (QEEG) is the measurement, using digital technology, of electrical patterns at the surface of the scalp which primarily reflect cortical activity or "brainwaves". A multi-electrode recording of brain wave activity is recorded and converted into numbers by a computer. These numbers are then statistically analysed and can be converted into a colour map of brain functioning.
What are the advantages of QEEG in comparison to routine EEG's?
The amount of data generated by multi-electrode recording is so enormous it is difficult for clinicians to interpret all the data. QEEG's address this data analysis and summarisation of data in the form of coloured topographic maps of the brain, spectral analysis and graphs. Other advantages are:
* Data Base Comparisons
A patient's/client's performance can be statistically compared to that of a large population data base. Such comparisons allow the clinician to determine whether or not brain functioning is abnormal, to what degree, in what locations and in which frequency bands.
* Pharmacological Activation Test Dose
The QEEG provides a simple, tangible way to determine whether or not a client/patient will benefit from a psychotropic medication without the need for an extended trial.
* Discriminating Functional and Organic Disorders
QEEG's can also serve as an effective tool for differentiating between organic and functional brain disorders. This functional data provides an excellent supplement to data obtained from CT scans and MRI's. For instance, QEEG is a useful tool for differentiating between physiological and functional causes of depression and hyperactivity. It has also been helpful in the identification of schizophrenia and dementias. This procedure can be employed to identify cases of cerebral atrophy associated with alcoholism or drug abuse as well as determining whether a child is presenting with neurologically based attention deficit disorder or one of psychogenic origin.
* Simplicity of the Procedure
The procedure has the advantage of being non-invasive an of requiring no more than a few hours administration.
* Coloured Dynamic Brain Map
The coloured dynamic brain map generated by a computer makes it easy for clients/patients to visualise the problems which are being explained. Thus it facilitates communication and improves the client's (and family's) understanding of their conditions.
The sister technology to QEEG is called EEG biofeedback, neurofeedback or neurotherapy.
Neurotherapy is EEG biofeedback based on operant conditioning of EEG characteristics. The qEEG provides the "targeting" information by telling us where and under what conditions (reading, listening, maths etc.) the problem is worst. This analysis allows accurate electrode placement for feedback and suggests tasks that should be used during training. The EEG feedback signals the client when their brain is in fact in a more activated state, indexed by decreased delta (0.5-3Hz) and theta (4-7Hz) brain wave amplitudes and increased beta (12-18Hz)/alpha (8-12Hz) amplitudes.
For who would a QEEG be appropriate?
QEEG's are initially performed to determine the presence of focal or generalised cerebral dysfunction
following a closed head injury, stroke, heart attack, or pulmonary dysfunction following hypoxia;
when seizure disorders or tumours are suspected;
in suspected cases of Attention Deficit Disorder
in suspected cases of specific learning disabilities
in suspected cases of cerebral dysfunction related to substance abuse;
when pathological alterations in vigilance (narcolepsy, confusion, coma) or acute nervous system processes (acute headaches, vomiting, aphasia) have been observed;
to investigate cerebrovascular disorders.
QEEG's can also be used
as follow-up to monitor organic brain syndromes, alcohol withdrawal, chemotherapy/radiation treatment, withdrawal from psychotropic medication or illicit drugs;
to follow-up on infectious diseases such as encephalitis or meningitis
to follow-up on post-operative status.
What is the client's experience?
An ECI electrocap is placed on the head to facilitate ease of administration and consistency because it provides predetermined electrode placements. Then gel is inserted in each electrode to make a good connection. There is no pain or discomfort with this procedure. Recordings are then taken under four conditions: eyes closed, eyes open, a visual spatial task and a maths test.
What information is received from the QEEG?
The SKILTM Topometric QEEG provides information on brain functioning and its impact on cognition and learning. Computerised EEG results are compared to age-related norms of the QEEG database providing information about whether the client has a deviation in QEEG functioning which varies significantly from the norm. It indicates what locations, the amplitude and frequency of waves of interest, and under what conditions the abnormality manifests itself. Advanced artifact removal, time of day correction, multiple data and statistical displays, and state comparison analysis differentiate the SKILTM from other QEEG systems.
The information is visually summarised in five graphical displays: topographic maps, spectral plots, topometric distributions, covariation maps and tables. A written report follows ten days to a fortnight later.
The History of QEEG testing and neurotherapy
The 1970's and 80's were decades of exploration and experimentation with QEEG. The American Medical EEG Association (AMEEGA) Adhoc Committee on QEEG has stated "QEEG is of clinical value now and developments suggest it will be of even greater use in the future". The use of the QEEG in assisting the diagnosis of mild traumatic brain injury, ADHD, learning disabilities, stroke, and epilepsy is well documented.
Neurotherapy is based on the work of Professor M. Barry Sterman of the UCLA School of Medicine, Departments of Neurobiology and Behavioural Psychiatry. Professor Sterman recognised how brain function can be altered and normalised by operant conditioning of the EEG. QEEG and neurotherapy has been endorsed by the American Psychological Association as within the venue of psychologists with appropriate training. Neurotherapy training to decrease slow wave activity and increase fast desynchronised EEG activity has been used for over 20 years to ameliorate ADHD and epilepsy and is well documented in the scientific literature. More recently EEG operant conditioning has been successfully applied to patients with mild traumatic brain injury.
If QEEG and Neurotherapy are so good, why aren't more clinicians using it?
Most psychologists and physicians simply have not been educated in the clinical applications of EEG biofeedback and are unaware of the existing research and clinical literature, in spite of the fact that the applications to anxiety, epilepsy and attentional deficits date back to the 1970's.
Furthermore, the instrumentation is expensive and requires serious study and training to use competently. An estimated 700 clinicians are using neurotherapy and QEEG in the U.S.A. Although relatively new to Australia, a growing number of psychologists and psychiatrists are now beginning to use these tools each year to assist in client evaluation and thus in choosing appropriate treatment modalities.
QEEGs allow neurofeedback therapists to address the physiological basis of psychological, psychiatric, and neurological problems without medication. It and can also be used in conjunction with medication.
Abarbanal, A (19950: Gates, states, rhythms and resonances: The scientific basis of neurofeedback training. Journal of Neurotherapy, 1, 15-38.
Sterman, M.B.(1996): Physiological origins and functional correlates of EEG rhythmic activities: implications for self regulation. Biofeedback & Self Regulation, 21,3-33.
Zametkin, A.J. et al (1993): Brain metabolism in teenagers with ADHD. Archives of Gen. Psychiatry, 50,333-340.
For further information/appointments for QEEG assessments please contact:
Gregory J. de Montfort & Rosemary Boon at
Learning Discoveries Psychological Services
P.O.Box 7120, Bass Hill NSW 2197
Telephone: +61 2 9727 5794 Fax: +61 2 97542999