Peak frequency is a statistic that tells us what the frequency within a band was that had the highest amplitude. For example, in the alpha band (8-12 Hz), 10 Hz should be highest in most adults. Values rising above that may result in problems experienced by the client, depending on where we see this, and peaks below 10 can often result in cognitive difficulties, word-finding problems, etc. The TQ shows you peaks in alpha, beta and the overall peak. Looking at the three together, once you understand more about the EEG and the assessment, you can tell a lot about a brain.
The great majority of the brains I’ve seen over the years don’t stay in one state or frequency for long periods. One great benefit of the brain lies in its very ability to shift states on a dime depending on what task lies before it, but that seems to disappoint and irritate you.
Frequencies Below 1 Hz
Any EEG value below 1 is not AC EEG that we train. It’s DC. It’s not produced in the cortex, nor even in the brain’s subcortical areas, as are the AC frequencies. It appears to be a signal from the brainstem. The published research that’s been done, or at least what I’ve seen, has been done on Slow Cortical Potentials (SCP) which range from about .3 to about .8 Hz, and it was done by serious researchers in Germany who recognized the danger of artifact from any kind of movement at all and used special techniques to identify and screen it out.
0.1 Hz means that your heart is pulsing 1/10 of a time per second–or 6 beats per minute. So 0.01 Hz would be a heart rate of 0.6 per minute or one heartbeat every 10 minutes. Good luck with that. A heartrate of 60/minute, for an athlete in top condition and resting would be 1 Hz.
The rhythm generator for the delta rhythm is the brain stem and hind-brain—it is not of the autonomic nervous system. Delta is unconscious.
Generally, delta in the 0-2 Hz range indicates that part of the brain is in a state of deep sleep. At times this is not good. Delta in the range of 2-5 Hz indicates drowsiness and may be the result of the training being done. Sometimes a change of diet does more to alleviate this problem than biofeedback. The culprit is usually sugar, processed flour and cereals or the drinking water.
Delta isn’t a really common thing to find. Spikes of it can be related to head injuries or artifacts. (Delta is also the frequency of the coma), and it can be resistant to training. Sometimes when it falls, other things appear, which is why I like to leave the squash in place.
Generalized slow activity is often effectively trained on the midline.
We may define delta differently from a neurologist, and there are many definitions of it. Neurologists often look at the morphology of wave patterns, especially looking for epileptiform activity. We look at numerical values representing amplitudes in each frequency. If we define delta as 1-3 Hz, as we do in the TQ Assessment, then a fair portion of that is 1-2 Hz., and there is no argument that activity this low in a waking EEG is largely artifact. However, saying that finding delta anywhere in any amount in someone in a resting state is abnormal would be a stretch in my experience–and I’m guessing also in that of those who use QEEG’s. Delta can be present without being abnormal. It’s a matter of how much of it and where it is and what happens to it when we activate. It’s perfectly possible that we are more likely to be asked to do assessments of folks who are “abnormal” in a neurologist’s terms. Certainly a preponderance of slow activity is a very common finding in our clients, and that’s not “normal”. I’ve looked at my assessment a number of times. Look at your own. See any delta there? I see it in mine. But you and I and many of our clients are functioning fairly effectively. So maybe “normal” isn’t a very useful concept in this case. When we see delta levels higher than we expect, then we have a training option, especially if there are performance issues that appear to be related.
If you find a spike of delta in one site or some contiguous sites, it can be an indicator of a lesion–normally white-matter damage, with neurons still functional but not connected, so they aren’t sending or receiving signals and drop to the lowest common-denominator rhythm, delta. This is not likely the issue if you are seeing delta all over the brain.
As a rule general, evenly distributed, high amplitude delta is indicative of slow brain maturation and training to decrease Delta amplitude usually proved beneficial. Almost any location will work but FZ, CZ and PZ seem to work better most of the time. Training to increase Alpha amplitude at PZ eyes closed also proved to be beneficial.
Temporal high amplitude Delta in the 0-2 Hz range usually accompanies a brain that is not very alert. Temporal high frequency high amplitude Delta in the 2-4 Hz range is an indication of an intuitive mind. This can be confirmed with high amplitude 100 Hz on either the right or both temporal lobes. (Training 100 Hz to increase intuition did not work.)
Frontal high amplitude Delta usually accompanies low levels of concentration, focus, attention and awareness. The lower the frequency of the Delta the more difficult to resolve these issues. Obsessive behaviors tend to manifest more with lower frequency frontal Delta. Training to decrease frontal Delta usually proves beneficial. I had good luck by training to decrease frontal Delta (0-3 Hz) while increasing parietal Alpha (10-14 Hz) either concurrently or following the Delta work. I would definitely try a squash or windowed squash, starting, say, at Afz/A1 and Fpz/A1.
I never did much work with high amplitude central or parietal Delta but I did observe that training to increase parietal Alpha tended to decrease parietal Delta and that excessive central Delta tended to decrease while the client was working to decrease frontal Delta.
According to the research done at the research center I ran while working for Lexicor, it all depends upon where the high amplitude delta is located in the brain, the frequency of the delta and the delta coherence between any two locations. In my opinion and experience anytime inhibiting delta is not working well, the problem is hyper coherent Delta. Find the locations involved and break up the hyper coherence and the delta “problem” is quickly resolved.
Generalized delta can be an indication of dissociation as well. People who have had traumatic experience will often have high levels of delta in which are buried the experiences that could not be processed.
And generalized delta can also be related to poor blood supply and hypo-oxygenation, which results in neurons being unable to sustain higher frequency pulse rates. Very often we see children who had early births or long or difficult birth processes (cord wrapped around the neck, long time in the birth canal, etc.) whose brains simply don’t provide much oxygen.
When delta “increases” at task at the F and even C sites, you might want to rule out that it is simply eye movement or eye blink activity.
There is some evidence that, as delta is the unconscious mind, Synchronous delta (not just delta) can be related to a kind of connection to the collective unconscious.
With delta and theta and even some of alpha there is a difference between synchronous and de-synchronized activity. Synchronous delta might be related to tuning in to the whole., but delta in most brains during waking states is not synchronous. It just represents very low metabolic activity, and perhaps low oxygenation.
As a rule, hyper-coherent delta is indicative of a closed head trauma while hypo-coherent delta usually accompanies learning disorders. Break up the coherence by training in the opposite direction for five minute intervals using an A – B – … – A format of 1, 3, 5 or 7 five minute mini sessions or until the client tires of the process. Change the direction of the training. Repeat this process but always end by training in the same direction as your first mini session training.
Theta is defined by some as 3-7 or 3-8 Hz and others as 4-8 Hz. Many more experienced trainers tend to prefer staying away from the Greek letter denominations and just talk about frequencies themselves.
3Hz activity is kind of a crossover point between delta and theta. It is a frequency which you generally will want to reduce. It is a very internal state, sometimes even a dissociative place, where contact with the environment is pretty minimal. It is also a frequency at which abreactions–re-experiencing of old traumatic material–takes place.
Theta in the 3-6 Hz range is more indicative of dissociation. In my experience abused children and women tend to have this low Theta that is difficult to differentiate from high Delta. If the client with high amplitude Delta in the 3-6 Hz range is alert and attentive, this is a good indication of low frequency Theta rather than high frequency Delta.
5Hz activity is still in the slow end of the theta range. It seems to be more related to cognitive issues, so you will often see lots of it in those who have learning problems, dyslexia, etc.
Getting up into higher theta, 7Hz theta is generally considered to be hippocampal theta. Its rhythm generator is the hippocampus, the brain’s main memory center. 7 Hz activity seems to show up when information is being put into or taken out of memory. 7Hz, hippocampal theta activates on the frontal midline (Fz to Cz) at task when memory is involved. It’s not necessarily the same thing that one sees when a client has a lot of theta.
6-8 Hz theta seems to be the frequency that most relates to memory, visualization and access to the subconscious. That’s why we train for 7 Hz crossovers in alpha-theta training, which ideally takes the client as an observer to the entrance to his own subconscious mind.
7 Hz is seen in various areas around the brain, though especially in the frontal midline (around Fz) when memory processing is taking place. It is called “hippocampal” theta, because it is a rhythm produced in the hippocampus, the memory center inside the temporal lobes, and appears in the cortex.
7Hz is also a visualization frequency. I like to train that (either through alpha/theta or directly) in the parietal or occipital lobes to improve a client’s ability to visualize performance in advance of doing it, a kind of programming of the subconscious with the desired outcome.
7Hz is also the crossover frequency we aim for in alpha/theta training. At that frequency clients tend to have visual images of old memory material, but it takes place without the client actually re-experiencing or abreacting that material.
Source of Theta
I believe there are two sources for theta in the sub-cortical brain: hippocampal theta, which is related to memory functions, is around 7 Hz. Lower theta is cortical response to rhythms from another area of the thalamus from that which produces the alpha rhythm.
Theta’s “globality” is more related to the fact that it generally emanates from a single source wherever you find it. However, training it down in one place doesn’t necessarily have any global effect on theta amplitudes. When you train down theta–as when you train down alpha–you are de-synchronizing specific pools of neurons from sub-cortical rhythm sections. This makes it easier for them to do specialized beta functions. You are probably also pushing blood supply to those neurons–and not necessarily all neurons.
Theta can be synchronous or asynchronous–the result of low metabolic activation.
Theta is a visual frequency in general (or at least a non-language processing frequency), so any task, like watching a movie, playing a video game, taking something apart and remembering how to put it back together, etc. are done very well with slower frequencies. The chances are that the high adrenaline content of many video games keeps the sleepy brains of ADHD kids awake, which is why they like them. It’s like risk-taking behavior, which many ADHD’ers also engage in a great deal.
Training down thelta (delta/theta) in a very slow brain requires the brain to work harder than it is accustomed, so train for short segments (I often suggest 2 minutes) and take breaks between segments (1-2 minutes is usually fine). Training up SMR, which is related to the ability to go from drowsy stage 1 sleep into stage 2, where you are actually asleep, often results in drowsiness early in training, though usually it doesn’t last long after a session.
More troublesome theta in the frontal lobes is usually found in the lower end of the frequency band (2-5 Hz), and it increases when the brain is trying to do a task, when it should be decreasing. And it is the relationship of theta to alpha and beta speeds more than the absolute amplitude of any one of them that is much more useful in determining if there is a problem worth training to achieve a specific behavioral/mood/performance outcome. If the relationship between alpha and theta is well below 1:1 with eyes closed, or if theta divided by beta is well above 2, then that may be worth training.
The combination of low theta/beta and high alpha/theta ratios most strongly suggests extremely low theta–perhaps especially in the 6-8 Hz band, but very possibly in low theta and delta also. That points to what is very frequently the underlying picture of any somatized pattern, a blockading of the subconscious. Theta (and particularly 6-8 Hz) is the gateway to the subconscious. Good levels of alpha provide a bridge across which subconscious material can reach the conscious and vice-versa. Extremely high or low alpha/theta ratios indicate that this is not happening–either there is no bridge (low alpha) or a drawbridge stuck open (high alpha).
There’s probably not much written about getting into theta, since most neurofeedback is about getting OUT of it. There’s no real problem to getting into it. Just stare off into space and daydream, or close your eyes and let yourself drift toward sleep, and you’ll go into theta dominant states. There’s a big difference between synchronous theta and asynchronous theta, which is a kind of spaced-out unfocused state.
Anything that moves a person into their head and out of contact with the environment will increase theta. It’s like the sick dog syndrome. The animal goes away and finds a place to hole up and let nature take its course. We humans (if we don’t get sucked too far into the healthcare system) tend to do the same. In a client’s case, if she’s “going away” the same as an ADD child does, by going into that internal, intuitive theta state, helping her to keep from getting “stuck” there is a perfectly appropriate and effective training goal.
Reading and Theta
Some people who use lots of slow activity actually read with theta. Since theta is an image-based processing speed, a person who “makes a video” of what she is reading will actually do exactly what you are describing. And, of course, will have a lot of trouble remembering details from what she read.
Alpha is the bridge between conscious (beta) and subconscious (theta) states. Alpha peaks should be around 10Hz. Alpha would be expected to be higher in back and on the right (except that O1 is probably higher than O2). The alpha frequency comes from the thalamic pacemaker (that’s what is meant by diffuse alpha projection system), and if you speed it up anywhere, you tend to speed it up everywhere.
People who don’t produce effective alpha are usually locked on one side or the other of the divide between conscious and subconscious states–theta processors get the ADD label because they have difficulty with the logical-rational language-based sequential processing states related to beta; beta processors are often locked away from their feelings and deeper memories. The ability to get into the alpha observer state allows one to consciously be aware of feelings.
Alpha is known in neurological terms as DPR (dominant posterior rhythm), because it dominates in most brains in the parietal and occipital lobes. It has a pretty specific sinusoidal form, much smoother than most frequency forms, and it has a specific characteristic that identifies it. When eyes are closed, in most brains it becomes very strong, and its amplitude tends to drop strongly (at least 30%) when eyes are opened.
So if the DPR appears in frequencies such as 6-10Hz, it’s still really alpha in terms of what alpha is like experientially. The wave form looks like alpha, though slower. And we can guess, seeing such a thing, that we are dealing with a rather young child, a very elderly adult or someone whose brain is quite tired. In any case, the information has some important training implications.
One of the signs of aging in most brains is a slowing of the alpha rhythm so the peak frequency drops below 10 Hz.
Alpha is most natural in the parietal/occipital lobes. Higher alpha frequencies in the back tend to relate to better working memory performance (and thus better scores in IQ tests), while higher peaks in the front relate to anxiety. However, an alpha peak differential in one site may indicate damage there, and since T4 would be highly related to anxiety, I would certainly train there. T4 and Oz being high suggests that O2 might be even higher than Oz. A right posterior head injury could be indicated. Training at either site to reduce 12-15 and increase 6-11 might be helpful.
People with slow brains usually have slow alpha as well. Slow alpha results in all kinds of cognitive problems.
When the peak of alpha is below 10 Hz (as we see in the TQ), semantic memory suffers, working memory suffers, you may become more depressed/low energy, sleep and ability to learn (related to working memory) will tend to deteriorate. One way of looking at this is to look at the relationship between 8-10 Hz alpha and 10-12 Hz alpha. If the ratio of high alpha to low alpha is 1 or a bit higher, that’s probably good. If it’s below 1.0, then you’ll probably experience some of the above problems (also called age-related cognitive decline because it happens to many of us after we pass 50 or so).
The biggest alpha consideration in older adults is very likely that it is slower than it should be. If you check for alpha peak frequency (you can do this directly with the EEG software), you will almost certainly find it below 10 Hz–perhaps well below. Training the alpha peak frequency back up to 10 Hz in the back and 10 or higher in the front is one of the main things I have done in my BrainPrime program with older adults, and Tom Budzynski also mentions this issue.
According to Jay Gunkelman (and this actually seems to work), the best way to diminish slow alpha (8-10 Hz) is to increase fast alpha in the parietal/occipital area. I like to train down 2-9.5 Hz and reward activity at 10-14 Hz at P4 or Pz or even O1 or Oz. The idea is that alpha is generated by rhythm generators (sets of nuclei) in the thalamus–a different site for slow and fast alpha. (BTW, slow theta, 4-6 Hz, and SMR–12-15 hz in the sensorimotor cortex–are also both generated by separate rhythm generators in the thalamus). In either of these cases, when you train down slow alpha and train up fast alpha (or train down theta and up SMR), you are encouraging the cortical neurons we can see in the EEG to switch from linking to the slower generator to the faster generator. Since alpha and SMR are regional rhythms, getting the neurons to switch in one area tends to get them to switch in others as well.
As alpha begins to slow–and often begins to move forward as well–the somatic effects begin to be felt.
If alpha is reversed in the parietals–that is there is more on the left than on the right–that could be related to sleep problems and a kind of negative/depressive view of the world.
In the TQ Assessment, alpha asymmetries could be a likely candidate to cause These problems, either too much on the left or too much in the front. Motivation problems are often related to alpha or excessive slow activity in the frontal midline area around Afz and Fz. General slowing in the left frontal quadrant would also be likely, as could be generalized slowing around the brain. Low levels of alpha (especially EC) in the back of the head or very low slow-frequency coherences could also be related.
In Davidson’s article published in 2005, he extended his work showing the importance of alpha dominance in the right prefrontal in two ways. First, he found that an alpha imbalance anywhere in the brain seemed to be related to the more negative, risk-averse, view of the world; second, he found that the imbalance in higher alpha (10-12 Hz) seemed much more important than in lower alpha.
When you look at the Analyze page in the TQ7, you’ll see that all site pairs give the ratio for beta, alpha and high alpha. I usually look for sites that are below 1 on most or all of these values as being prime places to train.
High Amplitude Alpha
It is possible to have too much alpha, and it shows up as high alpha/theta ratios, slow alpha, or poor alpha blocking.
We talk about alpha being the bridge between subconscious (theta) and conscious (beta). Very low levels of alpha: No bridge, and the client remains unaware of subconscious processes. But very tall alpha bridges can be conceived of as a drawbridge stuck open: you STILL can’t get across from one side to the other. One of the characteristics of the high alpha person is a kind of anesthesia, like wrapping the brain in cotton, which very often in my experience results in a somaticization of the emotional material. Lots of fibromyalgia, chronic pain and chronic fatigue folks show this pattern–especially if the alpha peak is low, and especially if there is a lot of alpha in front.
Too much alpha can be as much a problem as too little, especially if it doesn’t block. Very high alpha (especially when it is a bit slow and doesn’t block well–it still is dominant with eyes open) is the “drawbridge stuck open”. The drawbridge is that type of bridge that opens in the middle to let ships pass, then closes so vehicles can cross it. This is a kind of self-anesthesia which keeps a client from feeling emotional drive issues and dealing with them. The result can be a kind of “numbness” emotionally, and often as the client reaches their 40s and above, it can be found in people with chronic pain or fatigue.
With high alpha, I would wonder about drug use or drinking, especially if it is also high in the frontals. The effect of the high alpha can be kind of like wrapping the brain in cotton batting, so the client doesn’t experience much, and cognitively it’s like shifting into auto-pilot when he should be landing the plane. Why the brain has chosen this pattern is an interesting question–sometimes a way of protecting against stressful events.
Long-term meditation might result in overall high levels of alpha, especially if it is synchronous. Generally though that would be related more to back of the head sites, and it would block effectively with eyes open and at task.
Slow alpha being high could relate to marijuana use over a long period, which your client says has not happened.
Also, high levels of alpha that don’t block at specific sites can be an indication of a gray-matter head injury.
If it is high (especially slow alpha) everywhere, there is the possibility that it is the brain’s response to a trauma that has not been integrated (emotional trauma), and the brain is using the alpha as an “anesthetic” to keep from feeling it.
You can train down globally high alpha on the midline or on the left or toward the front–the areas of the brain that should be faster. Take a look at her histograms and maps with eyes open and see if alpha is not still dominant. I would generally try training it down with eyes open, though doing it with eyes closed may be useful as well.
It’s likely that anxiety is related to the high peak alpha frequencies.
High alpha in the temporals, especially if it stays high with eyes open, could certainly disrupt memory function or emotional responses which are linked to the temporal areas. Since F8 is an emotional regulation area, any excessive slow activity or alpha there (again, especially with EO) would indicate it was having difficulty doing its job.
You can absolutely have excessive alpha in the back. There is a whole class of client who are anxious and even compulsive who have very high eyes closed alpha levels. However, there are also heavy meditators who produce lots of it. I’d say if the alpha/theta ratio is above about 2.5 with eyes closed in the P or O sites, that would lead me to try downtraining it. Especially so if the drop when eyes open is not below 1.0–or if the ratio rises again at task.
Now in a relatively activated brain (perhaps more so in a very active brain) beta and alpha are antagonists. When you are producing alpha (synchronized with the mid-brain) you will be blocking beta; when you produce beta in the cortex, you de-synchronize from the alpha generators in the thalamus. Take a look at where the alpha is when it surges. If it’s in the 8-10 range, that would go along with the sleepiness; but bursts of 10-12 Hz alpha shouldn’t be a problem. If they still are, then try doing a squash, or training down the whole band.
Alpha at Task
Alpha should NOT go up at task, for sure! Alpha is the resting ready state–and this primarily in the back of the head, not the front. When you perform a task, alpha should drop, or stay the same, depending on how well it blocked with eyes open compared with eyes closed.
Alpha should attenuate (reduce in amplitude) when eyes are open.
When alpha looks the same with eyes closed and eyes open, especially when this is true in the back of the head, it may be one of two problems:
1. Failure to produce alpha with eyes closed; this suggests the neurons aren’t willing or able to let go of their beta processing speeds, even when there is no task requiring those speeds.
2. Failure to block alpha with eyes open or at task; this suggests the neurons aren’t able to shift out of their ready/resting state and actually kick into gear to perform a task.
The best way to tell which is happening is by looking at the alpha/theta ratios.
If the ratios are low with eyes closed and in range with eyes open or at task, that suggests option 1 is occurring. Train for that by increasing alpha in the parietals. If the ratios are in range with eyes closed and high with eyes open or at task, that suggests option 2. Train for that by blocking alpha with eyes open in the front or central areas.
Also be aware, though, that ratios can be thrown off by very slow peak frequencies (as we would expect in children). If you look at the histogram and see the “alpha pattern”–high with EC, drop with EO and stay down at task–it may not only occur in the 8-10 and 10-12 Hz bands. It may be at 6-8 and 8-10, or even lower.
Alpha shouldn’t be high with eyes open. If someone is uncomfortable training with eyes closed, I’d wonder, instead of what’s NOT there (e.g. alpha), what IS there that could be trained down. Alpha and the betas don’t coexist well.
Too much alpha is better seen in a failure to go away (or block) when you open your eyes and perform a task. Alpha should be about 30% higher with eyes closed than open. Frontally, your theta/alpha ratio will usually run between .8 and 1.25 with eyes closed. If alpha amplitudes rise when you perform a frontal task (e.g. memorizing) that’s a sign of failure to shift out of the speed when you should. Alpha is a kind of “auto-pilot” state, and people who stay in auto-pilot when they should be “flying” the plane, often experience that “in one ear and out the other” sense when they try to process information.
A 30-50% drop is an expected level. More important, as Karen said, is that the eyes-open and task levels of A/T are below 1.0 in the back. If the client has high alpha EC and blocks to that level, then even if the drop is 70%, that’s fine. May indicate the client is a meditator, has high alpha coherence, etc. Also, as Karen mentioned, the very high alpha eyes closed can be indicative of anxiety or, as I just posted, chronic pain or fatigue
Intelligence and Alpha
High FREQUENCY posterior alpha has been correlated in some studies with higher scores on IQ tests and improved working memory. That’s not the same as high AMPLITUDE alpha.
I don’t say that low alpha peaks are related to low intelligence. Only that, in some studies, faster alpha peaks have correlated with better scores on IQ tests and working memory tasks. In some studies, not. But there is a definite change that occurs (what Tom Budzynski calls “age-related cognitive decline” as alpha peak drifts down below 10 Hz. Usually semantic memory is one of the first things to be affected, but there is also a description in many clients of the brain feeling fuzzy or foggy, difficulty learning new material, completing tasks, etc. This has no more to do with a person’s intelligence than does ADD. Very intelligent people can have either issue, but either will tend to compromise their ability to “show” their intelligence to its fullest extent.
When I mentioned senile dementia, it was because one of the definitions of this in terms of EEG is an alpha peak in the low 8’s or lower. Again, even highly intelligent people can be affected by this.
Meditation and Alpha
The Zen master pattern shows strong synchronous alpha and gamma, alpha high with eyes closed, blocking efficiently at task and with eyes open. Not much high-beta. Most prominently is the ability to be still and present most of the time, shift into focus on a task when one is at hand, and ability to shift back again when the task is finished.
Some people with low slow-wave activity do well training up slow activity (6-10 or 6-13) on the right side and in the rear of the head while limiting beta/high beta or even (in the 2C design) 13-38. Others who have slow wave activity, can train to reduce 9-13 or 12-16 with eyes closed to block fast alpha.
One of the keys, from my point of view, is to recognize that there is a relationship between activation patterns and mind states. If you can find the observer place within you: a state of still, calm, presence in the moment–no thought, no judgment, no “trying”–you’ll usually find that you produce the EEG you are trying to train. Consider the feedback as a mirror to show you when you are there.
In an alpha state, one becomes an observer–able to separate from an ego state. Holding on to any emotional experience and sense of what someone “did to” me, blocks me from entering the observer state. And I would argue that, with all due respect for psychology, that acceptance of my feelings about something that “happened to” me is not the same as letting the feelings dissolve. Not hiding them or denying them, but simply letting them go is, in my experience, the ultimate freedom.
Highly synchronous alpha can produce harmonics at 20 (and sometimes smaller ones at 30 and/or 40). It’s likely an artifact of the EEG measurement. Beta can often go up with alpha due to what are called harmonics. Activity at 10 Hz has a “shadow” effect at 20 Hz, etc. This may result in seeing a beta increase.
In the brain, especially sinusoidal waveforms (like alpha and particularly synchronous alpha) can set up “harmonics”, which are resonances that occur at multiples of the waveform itself. These are like the overtones, or harmonics, that give music its timbre. So beta at, say, 30 Hz can be beta, or it can also be a 2nd harmonic of a strong 10 Hz alpha activity. Since the former is likely to occur with eyes closed (when we would not necessarily expect to see high degree of beta at 30 Hz), it is more likely to be a harmonic frequency response. Also, harmonics tend to be narrow, like the little spike at 39 Hz mentioned in the earlier post. Ordinarily we don’t expect to see that kind of picture in the brain, since the EEG usually looks more like a class picture, with a variety of amplitudes clustered around one another, than like a picture of a Lombardi Poplar in Nebraska, with a single tall item with nothing around to support it.
Alpha/theta ratios with eyes closed in the front would be expected to be around 1.0 to 1.5 (in the back, 1.5-2.5). With eyes open they should drop to around 0.7 in the front and 1.0 or below in the back.
If alpha is very high in front, especially if it doesn’t block 30-50% when eyes are opened or task is performed, especially if it is slow (8-10 Hz) alpha, those are all patterns that could relate to low motivation and difficulty with control functions as well as attention.
If you look at the Histograms page and see that the level of “SMR” is much higher with eyes closed and drops with eyes open, then you may be dealing with fast alpha, not with SMR. Especially if this appears in the front half of the brain and the client wants to deal with anxiety, then you may want to train to change it.
Whenever you look at a ratio, it’s worth seeing whether the ratio is high or low because one side is very low or the other is very high.
If the alpha/theta ratio is high, it could be that alpha is roughly in the range in terms of amplitude as it is elsewhere in the brain, but the theta is very low. Or it could be that the alpha is much higher than elsewhere.
If theta is low–especially in the back–that suggests that there is subconscious material the client is cutting off. Especially if alpha is slow and doesn’t block well with eyes-open or at task, training to let the brain come in contact with that material is a good thing.
If alpha is particularly high–especially in all three states–in one spot or contiguous spots or even opposite spots on the head (e.g. O2 and F3), that may well be the result of gray-matter head injury sometime in the past.
A large spike of alpha in the occipitals can also suggest that there is traumatic experience–usually visual–that is being dissociated.
Alpha Beta Relationship
Beta and alpha are antagonists. A neuron not involved in a task can resonate to the brain’s alpha generators. A neuron performing a task produces beta. It can’t do both at once. As you are able to release the fast activity, the alpha may start up, or you can train it up.
If increasing beta does not decrease alpha, this is an indication that the brain is under-aroused. When beta rises and alpha falls (or vice-versa), brain activation is in a good range.
It’s fine to use something like 19-38 or 23-38 Hz inhibits and 6-13 or 9-13 rewards, but don’t be surprised if the “reward” band doesn’t go up–or even goes down. You are asking the brain to pat its head and rub its belly at the same time. (re: training down beta and up alpha at t3/t4)
Alpha and Brain Injury
When alpha shows a spike at a site relative to the rest of the head, one of the first things to rule out is a closed head injury. Gray matter damage (neurons, not axons) results first in reduced amplitudes in all frequencies (fewer neurons to fire), but as the neurons are replaced the amplitude comes back–though the connections don’t–and it’s not uncommon to see a spike of alpha.
There is research that links posterior alpha production with serotonin release.
Mu is just a normal variant of alpha. It shows up in about 20% of young adults. It often seems to exist in EEGs with a lot of frontal slowing–as you might expect in ADHD. However, when you train SMR up, regardless of the frequency, you aren’t necessarily impacting mu–even if there were some reason NOT to do so. Alpha and mu both exist in the same frequency band, but training up alpha doesn’t necessarily affect mu.
So you could try hitting the slow frontal activity first, which could help reduce the mu and improve impulse control; or you could just find your SMR rhythm and don’t worry about mu; or you could have the client imagining himself moving while he sits very still and relaxed, which should raise SMR and block mu at the same time.
Mu should be found in the sensory-motor cortex over the dominant hemisphere, more than likely the Left. In which case, training at C4 over the right hemisphere shouldn’t affect it anyway.
Every 5-year-old I’ve ever trained has figured out in a matter of minutes that moving a finger or hand will make it go away. The only way to separate out Mu waves, if you really want to, is to look at the morphology of the wave forms or just have the client move his/her hand. If the activity drops as long as there is movement, it’s Mu.
Mu isn’t a problem, so don’t waste your time training it.
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Alpha or MU?
If you want to worry about Mu waves, then you need to look at the raw EEG tracing. That’s the only way to tell the difference between alpha and mu. Mu has what is described as a “wicket” shape. They can occur in the frontal sensorimotor cortex or other motor areas, so they may be actually slowed SMR pulses.
Alpha is primarily found in the rear of the brain, over sensory areas.
SMR is the frequency above alpha in the sensorimotor cortex, between C3 and C4. In adults, alpha is expected to have its peak at 10 Hz, in a band from 8-12 Hz, so SMR is likely to be around 12-15 Hz. In children of 8 years, the peak alpha frequency is often around 8 (perhaps lower in children who are behind the developmental curve, as most ADHD people are), so the alpha band might be closer to 6.5-9.5 Hz, which would put SMR around 9-12 Hz.
Starting there usually makes sense and saves time with younger children, but often titrating down the frequency further will end up discovering a band where the body begins to relax and slump, eyes get heavy, breathing deepens and the client gets still. Some will even fall asleep. If the client becomes drowsy, you can start bumping the frequency back up 0.1 Hz at a time.
Remember that SMR does not exist in most neurology texts. It is simply called Beta 1 or Low Beta. Even in neurofeedback, it only exists in the central strip, between C3 and C4. It is a frequency that relates to the thalamic filtering system functioning effectively, controlling inputs and outputs from the brain.
ALL frequencies are variable by person. The definitions of frequencies were not brought down by Moses on stone tablets–they were defined by men (and there are many different definitions of them).
The best way to find the SMR band is empirical: start at 12-15 Hz (I like to use 13-15 or 12-16, so we keep 14 Hz in the center of the filter) and adjust it downward a little at a time if you don’t get the desired response. For those younger than 16 years, it will almost certainly be a lower frequency. You can look for the alpha band by looking at the power spectrum (brain mirror display) at P4 with eyes closed and eyes open. In most people a particular band will surge out and become dominant with eyes closed and then drop down sharply when eyes are opened. When you know where alpha is, then SMR is likely to be just above that.
The key, though, is to see the client’s body relax, muscle tone dropping significantly, and often becoming sleepy. SMR is also called “sleep spindles” at night, and it is correlated with the move from stage 1 to stage 2 sleep. When you find the right frequency, the change is often quite dramatic.
Training up SMR (or SMR%) at C4/A2 or Cz/A2 (often better for muscle and sleep issues) will actually lead the brain to increase the SMR relative levels at the target site.
SMR, like the other faster frequencies, is not intended to be a dominant frequency. It appears, as you can see on the Power Spectrum and the waveform display, in spindles or packets–as does beta. The question can be re-stated as, “should relaxing the muscles become the most important function the brain is performing at any given time?”, and the answer is very likely no. There are many other things happening at any given time.
Sleep and SMR
SMR helps you get to sleep, but the brain’s ability to stay out of beta and produce synchronous resting frequencies, including alpha, and to be able to desynchronize into beta without locking up are very related to ability to sleep restfully, have good REM cycles, etc. In my own opinion, training for a symptom–no matter how important–and sleep issues are near the top of the heap–often doesn’t have the desired effect. Training a range of patterns that actually exist in the client’s brain to help it improve its efficiency and effectiveness overall will likely have a better result on sleep along with many other things.
If you train SMR in a person who is sleep deprived, it is not uncommon–or undesired–to have him appear to sleep during the session. Watch for the big spikes in Theta and drop in alpha, if he has any, to see that he is really sleeping and not just in a deep resting state. In any case, training during this state can be very helpful in my experience.
Go with 5minute segments, then have him open his eyes and talk with him a little about how he feels, what happened with his eyes closed, etc. Then return for another 5 minutes. If he can fall asleep in 5 minutes, he’s REALLY sleep deprived.
Training Band for SMR
Train SMR where it is in children and where it should be in adults. Looking for the alpha shape, alpha strongest with eyes closed and then blocking 30-50% when the eyes are opened, is one way of identifying where the alpha peak frequency is–and that can help us determine where the SMR band may be.
If you are training SMR, you will be either inhibiting slow activity (and fast activity if it is present), or training to increase the percent of SMR (often achieved by reducing the activation in other frequencies.
Look for the client to become calmer and more still, perhaps begin to slump in the chair a bit (low muscle tone) and even sometimes get heavy eyes and have trouble keeping them open.
SMR helps with restless sleep, bruxism, tics, tremors and other involuntary uncontrolled behaviors.
The coaching for SMR is just let it happen.
I’ve had numerous experiences of clients who trained SMR and became ravenous following the session. We actually kept power bars and juice in the office because a) kids would arrive not having eaten anything in 3-5 hours; or b) kids who didn’t feel hungry at all suddenly became incredibly aware of their appetites following an SMR session.
Usually the only reason I’d train it down would be to see its effect in someone with spasticity or a locked up physiology. If it is super high percentage-wise, then I’d look at what is very low (unless the microvolt levels are really high as well). First thing to look at would be whether you have alpha bleeding over into SMR, very high Alpha PF. But if you have a very hyper kid, you could try training it down if it’s very high.
I’ve seen a nasty response to SMR on occasion, generally from people who don’t express anger easily, swallow or bury it. It seems to take the lid off a little and let some of the steam out.
The useful range of beta for most folks is from around 15 to around 22 Hz. Studies as far back as the 1970s have shown that some people experience the faster range (18-22 Hz) as intense focus, curiosity and engagement; others experience it as anxious and obsessive. Above 22 Hz, it’s pretty safe to say that the experience will not be good, no matter the age.
15-18 and 19-22 Hz are in the beta range. Most kids do better with the lower band, but a lot of adults like the faster beta. However, neither of these is “high-beta”.
Because the brain speeds up with age, with younger children you may have to drop the beta frequency below 15-18 Hz to find a frequency that results in focus without buzzing. By the age of 15, though, in my experience some kids do better at 15-18, some at 18-22 and some elsewhere in that range.
As far as percentage, I would consider 15-17% EC Beta to be a reasonable range. If the levels of beta and high beta are high and higher on the right (say 16%/12% or so), then that could be an indicator for anxiety. You have to be careful with high-beta rising at task unless you were very careful about tension. Muscle tension increasing is very common when someone thinks they’re going to be “tested”.
When beta is significantly higher than theta, you have a brain which is doing all it can to lock out access from subconscious material.
When a person is anxious and can’t stop thinking, you’ll usually see high beta. High beta or beta 3 is 23-38 Hz and should not be trained up. It’s not a frequency brains ordinarily make much, because it’s tremendously wasteful of energy and not particularly useful unless you are in a seriously threatening situation. Many people can cover their fear when they have something to pay attention to–though high theta is not necessarily “paying attention”–but when their eyes are closed, internal issues, or frustrated vigilance, can trigger the amygdala and appear as high-beta in the temporal. With eyes closed, clients can feel very vulnerable, and the fear comes to the surface.
High beta is 23-38 Hz–a 15 Hz band–compared with beta 15-19 Hz–a 4 Hz band. That’s nearly 4 time more frequencies, so it’s not at all unusual to see high-beta above beta a little bit. Just looking at the right side of the spectrum doesn’t help much anyway, because there are such great differences in alpha levels and it’s possible to have very high slow-wave activity as well. That’s why I look at the percent of total.
I would train to reduce it with eyes closed.
High beta in left temporal lobe
This pattern of very high left side often relates to lack of nurturing during early childhood–emotional neglect or abandonment instead of abuse. I think that finding something that reduces the activation at T3 will likely have the most positive effect. Chances are pain and sleep will improve with this training as well.
Gamma represents a pretty small share in most brains, and the overall band has increased from 40 to 42 Hz.
Jay Gunkelman did a fascinating presentation at FutureHealth in which he reviewed studies on gamma and its role as the “binding” frequency going back several decades. He showed quite impressively that gamma appears to be an adjunct to this state–not the driver as is often stated or implied in recent NF writings. His candidate for the true key player was slow cortical potentials (on which gamma “rides”) produced by the brain stem–the on/off switch for arousal and consciousness.
If you are really training gamma (which I usually do training synchrony), it shouldn’t have much of an effect on high beta. The gamma state is more of a communication connection. High beta is more like rumination, anxiety, pressure.