Author: Sue Othmer

Susan Othmer is Clinical Director of the EEG Institute. She has been involved in clinical research and the development of EEG biofeedback protocols since 1988. She teaches professional training courses in EEG biofeedback, and presents clinical research findings in professional forums.

Tracking EEG Amplitudes

Several neurofeedback clinicians have been reporting that they are tracking EEG amplitudes during training as a means of identifying the optimum reward frequency. The reported observation is that inhibit amplitudes, or amplitudes across the spectrum as seen in a 2D spectral plot, fall significantly when training with a reward frequency which produces a calm and alert state. If this is so, even just some of the time, it might be possible and useful for the software to detect the shift and bring it to the clinician’s attention. It occurred to me that we need a design that would allow for tracking of the various amplitudes over a number of time scales, so we can all see what is happening and share that information more effectively.

It is not unreasonable to expect amplitudes to decrease within session with appropriate training. The EEG is highly state dependent and can be used, for example, in tracking state changes in an overnight sleep study. Our desired training state is one of calm eyes-open alertness in which all frequencies should be low amplitude. Low frequencies might increase in amplitude as people become sleepy, foggy, distracted, fidgety, etc. And high frequency amplitudes might increase with increased agitation or tension. These state-dependent shifts are in addition to any EEG rhythms or bursts that are related to brain dysfunction resulting from developmental delays, injury, or physiological disregulation. I really wouldn’t expect low frequency bursts related to seizure or migraine, for example, to shift within a session. But even a person with a highly disregulated EEG will also show shifts in background EEG frequencies with state changes. Continue reading “Tracking EEG Amplitudes”

Working with Behaviorally Difficult Children

We are seeing increasing numbers of very difficult children. They may come diagnosed as Conduct Disorder, Oppositional Defiant Disorder, Bipolar Disorder, Reactive Attachment Disorder, Tourette’s, severe ADHD, or some combination of the above. The presenting symptoms might include unstable mood, physical agitation and hyperactivity, obsessive fears, emotional reactivity and over-reaction to perceived threats, need for complete control, rages, aggressive behavior, tics, impulsivity and attention deficits.

As we explore the benefits of inter-hemispheric versus left and right side training separately, we are rethinking the behavioral categories and how they respond to these different training approaches. We have also expanded our reach with our recent lower frequency training, which is proving very useful with this population. These behaviorally difficult children are generally very sensitive to the effects of neurofeedback. That is positive in that we are likely to significantly help them, but it also means that we need to be very careful in adjusting the reward frequency and in selecting training sites. These are kids we do not want to make worse. Continue reading “Working with Behaviorally Difficult Children”

Interhemispheric Versus Single Hemisphere Training

We have explored interhemispheric training over the past years, optimizing reward frequencies, and learning the specific effects of training different sites. Now that we have started also training left and right side separately again, we need to ask when and why we would choose to do one rather than the other. At first we moved to left and right side training in order to get low enough, especially when moving to prefrontal or parietal training. With our ability to train lower with narrower filters near zero, we can now separate the issues of frequency and placement. (See EEG Newsletter 14 May 2006.) Are there some people and some symptoms for which one approach is more effective?

We have moved people from one approach to the other at times in search of a stronger or more specific effect. We are now beginning to see that many people do clearly benefit more with interhemispheric or with single side training. Our task is to sort out any general rules that might guide us in fitting the protocol to the individual client. The emerging model is one of separating problems of instability of state from those of specific activation and arousal deficits. This of course brings us full circle to the initial need and rationale for interhemispheric training — stabilizing the brain against migraines with T3-T4.

We are finding that interhemispheric training (often specifically T3-T4) is proving more effective with global instabilities of state such as migraine, seizures, asthma, panic, vertigo, irritable bowel, mood swings and traumatic brain injury. I am expecting that it will also be more effective with PTSD, night terrors, sleepwalking and fibromyalgia. It may well be that interhemispheric coherence abnormalities will prove useful in pointing to specific interhemispheric sites that need training.

Left and/or right side training is giving stronger effects with activation and arousal deficits as with ADHD, anxiety and depression, OCD and tics, agitation, muscle tension, the autistic spectrum and probably RAD. In these cases we seem to get cleaner, more targeted effects and have an easier time finding an optimum reward frequency. We will need to rethink our categories of instability and sensitivity to fit these differential effects. It may be that hyperexcitabilities are impacted more strongly with interhemispheric training, while symptoms of disinhibition respond better to left or right prefrontal training.

So should we still start with T3-T4 or move directly to left and/or right side training with some individuals? The rationale for beginning with T3-T4 was that it asked the simplest question possible so as to give us the clearest answer. It was not left or right or front or back — just up or down to find the best reward frequency. More specific placements and effects could build on that. But we have already moved to right-side T4-P4 as the starting placement for RAD and autistic clients. Here the priority is to get individuals physically calm and settled and in their bodies. T4-P4 can be easier to figure out for many people because it specifically impacts body tension and agitation and awareness. This is a good place to start and continue for some sessions with autistic and RAD clients, but ADHD and anxiety/depression clients typically need to balance right posterior training with left prefrontal. So then the starting protocol would need to be both T4-P4 and T3-Fp1. Finding the optimum reward frequency at two sites might be a large task for the first session. We have a lot of history with T3-T4 as a starting place, so this may take time to evolve. If we do start T3-T4 and then shift to left and/or right side training, there are no firm rules to guide reward frequency selection. A reasonable solution is to start on the right side with the optimal reward at T3-T4 and expect to adjust as needed. The expected reward frequency on the left side is 2 Hz higher than that on the right.

We also expect that both approaches might be useful for some clients. It would make sense to stabilize first with interhemispheric training and then add more specific single sided placements for residual symptoms. We often see migraine clients benefit from T3-T4 very specifically, but then also need work on OCD or muscle tension symptoms. In such cases we would keep the T3-T4 in the mix, while adding other sites as needed and as they prove useful.

Left and Right Prefrontal EEG Training

For the last several years we have focused on interhemispheric EEG training including prefrontal Fp1-Fp2. Interhemispheric training influenced the activation of both left and right prefrontal areas and the coordination of activity between them. More recently we have moved back to left and right-side training separately in some cases. This brings us back to the issue of which functions we might impact with left-side versus right-side training.

Before interhemispheric training, we learned to carefully avoid right prefrontal training. At that time we were rewarding basic Beta and SMR frequencies, and we had found that T4-Fp2 training at those frequencies could precipitate emotional meltdowns or explosions. We now understand that right prefrontal training has a very strong impact and needs a reward frequency carefully tailored to the individual. At the time we settled on left prefrontal training (T3-Fp1 or T4-Fp1) to impact problems with attention and impulse control. Continue reading “Left and Right Prefrontal EEG Training”

Multiple Inhibits

We have recently shifted from wide inhibits to multiple inhibits in our clinic. This is useful in more clearly separating our understanding and implementation of rewards and inhibits. It also moves us along in shifting the burden of managing inhibits to the software and letting the clinician focus on adjusting reward frequency.

The wide inhibits (2-13 and 14-30 Hz) have effectively covered the entire range of 0-30+ Hz. High amplitude activity, meaning a transient increase in amplitude at any frequency, is detected and inhibited. We have for some while found the wide inhibits to be more clinically effective than narrower inhibit bands in most cases. And separate thresholds on the lower and higher frequency bands allow more effective feedback since amplitudes can be very different at high and low frequencies. Multiple inhibits now take us further in that direction, allowing the inhibit thresholds to fit the spectral like a glove rather than a mitten. Continue reading “Multiple Inhibits”

Reward Frequency — A Breakthrough in Getting Low Enough

While our inhibit filters typically cover the entire 0-30+ Hz band, it is clinically useful to target the reward frequency very specifically for each individual and each site. We find that the optimal training band can be anywhere from 0 to 30+ Hz. We also find that the majority of our clients need reward frequencies much closer to 0 than to 30 Hz. Every time we find a way to train which allows more calming, it seems that we have a surprising number of clients for whom we wish we could achieve even more calming.

With interhemispheric training, we know that the optimum reward frequency at T3-T4 (or C3-C4) for a given individual reliably predicts the optimum reward for interhemispheric training at parietal or occipital sites (4 Hz lower) or frontal or prefrontal sites (2 Hz lower). Since many high-arousal clients need a T3-T4 reward frequency lower than 4-7 Hz, we are unable to train low enough when we move to the back of the head. This is often a problem for autistic, reactive attachment disorder or bipolar children, and even for very hyperactive ADHD children. Continue reading “Reward Frequency — A Breakthrough in Getting Low Enough”