WHY A QEEG?
The QEEG is a quantitative electroencephalogram. The QEEG is an assessment tool to objectively and scientifically evaluate a person’s brainwave function. A QEEG is similar to a regular EEG except that instead of having the neurologist look at the brain wave recordings across a piece of paper, the QEEG analyzes hundreds of samples of brain activity and compares them to age matched norms. The brain maps that emerge for the individual can then help to determine which if any of the brain activities recorded are outside normal values, and if so, how and where do they differ. Normal values are often used in medicine to determine whether something may be amiss. Blood tests are just one such example.
There are other reasons why a practitioner will suggest that a QEEG is an essential component before beginning any form of neurofeedback training. One of these being that during the examination of brainwave data, should seizure activity be noticed then an immediate referral can be made to a qualified neurologist. Another reason is that the QEEG provides an objective baseline to measure change whether from neurofeedback training or any other intervention. Yet another reason to consult a QEEG before any type of neurofeedback is that some brain activity is outside of normal values because the person may be gifted in some way, for example in mathematics or artistic expression. When the practitioner correlates the QEEG with the goals of the individual then training errors are minimized and only by measuring accurately can we know that what we are training is most likely to benefit the patient. Please see the article by Dr. C. Hammond, “What is Neurofeedback - An update” for a bibliography of many scientific peer reviewed papers on the subject of neurofeedback and the importance of the QEEG as a starting point.
The QEEG itself is a relatively simple procedure whereby a snug fitting cap is placed over the person’s head. The cap is filled with 20 electrodes and two earlobe connections that measure electrical activity at the scalp. These measures are then fed into an amplifier and stored in digital format for comparison to normative databases as mentioned above. Rest assured, the patient is not being exposed to any outside electrical activity or shock or any kind, it is only an assessment of that individual’s brainwave activity. The entire procedure typically takes about 40 minutes.
sLORETA QEEG and Neurofeedback: LORETA refers to low resonance electromagnetic tomography. This technology provides an estimation of the underlying brain generators being measured at the scalp (eg. the insula, the cingulate gyrus, the fusiform gyrus …) These brain maps look more like MRI slices and although research here is more preliminary than established, it is believed that neurofeedback with this approach can improve outcomes in difficult cases and also shorten treatment times.
Please also consider our paper on NEUROFEEDBACK FAQ for additional information on how the QEEG procedure is performed.