You often see clear abnormalities in the EEG with epilepsy, with head injury, or from a variety of other causes. When you train the EEG, there is often a reduction or elimination of those EEG abnormalities. For some clients, from ADD to depression to anxiety, training may also produce reductions in excessive amplitudes or variability. This is seen as a result of training over time. That excessive slow or fast activity, variability or timing problems (coherence) isn’t by definition an EEG abnormality. But those issues are highly-correlated with problems related to behavior, cognitive function, affect, and more.

For some patients, a specific amplitude change in the EEG cannot be measured, but improvement is seen in symptoms. It’s possible in these cases that the measure of change is not being recorded because the EEG is a complex wave form, and there are many locations on the head it can recorded. There are thousands of possible ways it could be measured.  The reality is you just may not always see the change. Even in a laboratory setting, there are times when no clear change is noted in the EEG. There’s only so much time and effort one can make to measure. There are ongoing efforts to develop new measures of relevant change.

However, the goal isn’t observing the EEG change; it’s observing the client change.  If the client is making progress, many clinicians, particularly ones less technical, don’t worry about seeing a specific EEG change.

There are a number of therapists who don’t pay close attention to whether the EEG is changing. They stay tuned closely to changes in the client clinically. It doesn’t mean the EEG isn’t changing. Most training produces, at a minimum, subtle change in the EEG, and many clinicians focus more on training strategies, frequencies, and targeting specific sites or parts of the brain to train. It’s the clinical side of neurofeedback. This symptom and training-based model has worked very well for many years, and there is a very good course that has been developed to teach and target this approach.

Others believe that “normalization” of the EEG should always be a primary goal. That is, you should be able to identify something in the EEG that needs changing, and you should be able to see it change.

The answer is probably somewhere in-between. There are clearly times when the EEG is very dysregulated, with clear, excessive slow or fast activity. Most clinicians report that if they observe a reduction in that excessive slow or fast activity, it usually correlates with client improvements. Can you achieve the improvements without watching the EEG closely? Sure. But combining the two approaches to help encourage faster learning is probably optimal.

More research is needed, but both approaches work. 1) Training to normalize the EEG, and 2) training to improve symptoms. Recent research suggests greater changes in the EEG correlate to more change in cognitive function or symptom improvement. But does watching it matter more than staying tuned to the client? Can you do both? Does one produce better outcomes than the other? Every answer produces more questions.