Drug exposure and EEG/qEEG findings

A technical guide by Jay Gunkelman, QEEG-D

General comments:

There is a generally reciprocal effect between alpha and beta, as brain stem stimulation desynchronizes the alpha generators, beta is seen.  During states of under-arousal, this relationship is not seen, as when the subject is alerted, when both alpha and beta increase.

The point is that the arousal level changes the EEG responses expected, as when a stimulant is given to an under-aroused subject, increasing alpha. In a normally aroused subject, stimulants decrease alpha, and in an anxious (low voltage fast EEG variant) subject alpha will not be seen as changed by a stimulant.

Though there is a response stereotype for each medication, there are also individual responses, which vary. Mixtures of medications become too complex to evaluate each individual medication’s contribution, not to speak of synergistic effects not seen with any single medication, which may be seen in polytherapy.

The following pages represent a summary of many articles, papers, reviews and books on medications and the CNS function, and finally nearly 30 years of experience in clinical and research EEG. The difficulty in this area is the definitions of bands varies, the methods of analysis range from visual inspection of the raw EEG to quantitative measures, not all of which are clearly defined… and thus the need for a brief summary which puts this into a concise form for reference.

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Concern Regarding the Mitsar Amplifier

The concern regarding the Mitsar amplifier expressed with so much vigor by those with competing interests has met the reality test of actual recorded data.  The concern expressed was over a theoretical time skewing error due to the data sampling of an older version of the Mitsar amplifier.

I suggested at the time that all the emotion was merely an example of someone yelling “the sky is falling”, like Chicken Little. There was no real problem, just lots of crying out and hand wringing.

I requested in an open international forum for anyone to send me a sample of the problem, and none could be produced. I suspected there was no real problem, as the sample issue was concerning a 500 sample/second device having a time skew… though this was in comparison to a database collected on a 100 sample per second device, with the waveforms interpolated from these samples.

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Derived Feedback Metrics such as Z-score Training

As the technologies advance and the software speed starts to allow derived measures to be used for feedback, the field is being offered many new tools for neurofeedback, including ICA based feedback, LORETA based feedback, and Z-score feedback.

All of these new tools will require clinical validation prior to being able to be considered standard techniques within our field’s armamentarium of efficacious techniques and clinical applications. All of these techniques offer great hope at this time with preliminary results, but careful clinical outcome studies remain to be performed.

In this brief note I will discuss Z-score feedback. This promising technique offers to set normative boundaries around the mean of many features of the EEG, and allow feedback to be controlled by these parameters. This obviously offers great hope to clinical outliers, as their Z-score divergence should be related to their pathology. One difficulty is that database Z-scores also show divergence when an adaptive or counter-balancing feature is used to cope with an abnormal finding. A crutch is not a normal finding, but you can’t walk without it if you have a broken leg.

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Neurofeedback Demonstrated on “The Doctors”

On this episode of the Doctors Dr Michael Linden helps “Noah” with his ADD. Part 1 of this story give a bit of information about what Noahs parents have been dealing with and the struggle they face with deciding whether or not to medicate their young child.

In Part 2 you see how Noah parents learn there are alternatives to Ritalin and other drugs that may be given to their child. Learn about how Neurofeedback and EEG Brain Mapping may be able to help without the use of dangerous pharmaceutical drugs.

Dr. Linden is a Clinical Psychologist and Nationally Certified in Neurofeedback and Biofeedback. He is the director of The Attention Learning Center, which has offices located in San Juan Capistrano, Irvine and Carlsbad, California.

Dr. Linden is a regular contributor to the Journal of Neurotherapy and has been a speaker in many seminars and conferences related to ADD/ADHD and neurotherapy.