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Understanding your QEEG
Your Quantitative Electroencephalogram (QEEG) report contains information to help both you and your therapist decide what interventions may be helpful to address your concerns. At first glance, there appears to be a great deal of technical information, followed by a series of colored charts. This descriptive information is provided not only for your information, but also for your therapist. It may also be helpful for other healthcare providers should you decide to share the report.
The following summary is to help you better understand elements of the report so that you can use its information.
What is a QEEG?
Your QEEG is ultimately the measurement of the electrical interactions in your brain. These interactions occur when neurons are recruited in various areas of the brain and network together to complete a process -- such as a thought, an emotion, the experience of a sensation or an action -- and even thinking about an action.
Circuits and networks of neurons are responsible not only for our emotional state, but also for our ability to respond to problems effectively and to efficiently process information. A specific behavior doesn't occur at only one site, but through a network of different areas of the brain cooperating together.
The electrical component of your EEG recorded from all 19 areas of the scalp looks like this:
While it may seem difficult, it is possible to discern meaningful characteristics of the EEG by the naked eye, a trained clinician may be able to understand a bit more about your level of alertness or proneness to anxiety or inattention. These characteristics may not be seen as abnormal by a neurologist, but certain characteristics may be a contributor to your concerns. For a thorough review of research on these characteristics, please see the references at the end of this paper.
While a QEEG can be helpful to neurologists, it can also be useful in guiding other treatment, such as neurotherapy, psychotherapy or psychiatry. As a growing body of research strengthens our understanding of mind-brain-body interactions, professionals in the therapeutic community look toward psychophysiological assessments such as QEEG in order to maximize the therapy they are able to offer.
The report you have received is intended to inform interventions such as neurotherapy, biofeedback and other integrated treatments. It is intended to help you understand more about your concerns. It is not intended to pronounce a diagnosis, but to help in assessment. That said, if any characteristics in your assessment arouse suspicion of the clinician, she or he may suggest you consult your physician or have a neurologist look at your EEG. This is not cause for alarm; your clinician wants to make sure you are getting the most appropriate treatment for your concern.
What's in a report?
Not only will you see a sample of your EEG, you'll also see a collection of maps representing levels of EEG function. They will look like this:
These maps show relative amounts of "power," or electrical contributions of the EEG. This is calculated and quantified by measuring the raw EEG at 19 sites. Fortunately, there are a number of clinical EEG software programs capable of these mathematical complexities.
Many of the maps are "Z-scored," which means the relative amount of power is compared to a "normal" population so that your neurofeedback therapist can have a sense of how your brain function may relate to your concerns or symptoms. In the example above, the EEG was compared to the Applied Neuroscience Normative Lifespan Database, which is one of two databases with FDA approval (Applied Neuroscience, 2007). This database is a large collection of EEGs from individuals of all ages who have no history of concussion, mood, learning, cognitive or other concern. You are compared to individuals of your age.
When maps are "Z-scored," they attempt to tell you how far from "normal" a finding is. The distance is measured in Standard Deviations and based on a Bell Curve (or Gaussian Distribution). Here is a bell curve below:
So a map with areas coded in red would suggest an over-abundance of EEG function in a certain area. Blue would suggest a level of functioning that is less than what would be expected in the average population. You and your therapist will explore the degree to which your unique findings represent a problem for you.
The maps are also divided into different bandwidths, such as delta, theta, alpha and beta. These represent the speed of firing of groups of pyramidal neurons, with delta being the slowest and beta being the fastest. So the QEEG maps above tell us about the firing speeds of neuronal groups and how different they are from a "normal" population.
In the map example above, you'll notice some diagrams with lines instead of colors. These diagrams are an indicator of how different parts of your brain are communicating. They measure timing and the quality of timing from one area to another. This is important because all activities depend on a network of neurons all performing different duties.
You may already be familiar with the various lobes of the brain and their general function. The frontal lobe, for instance, is well known for its function in planning, paying attention and regulating emotion. However, it depends on neuronal functions in other areas of the brain to complete its tasks. As an example, the attention network encompasses more than 20 sites within the cortex (Trans Cranial Technologies, 2012).
What is a LORETA Image?
In addition to the color-coded maps, your report might have several images produced using functional brain imaging technology known as Low Resolution Electromagnetic Tomography (LORETA). You may also notice mention of "Brodmann Areas." While the maps shown above are more general, the LORETA image and corresponding Brodmann Areas are a more precise indicator of function.
LORETA imaging is a complex set of mathematics that uses the information from the 19 sensors on the scalp and triangulates what area within the cortex is generating the electrical potentials that we see on the surface of the cortex in the raw EEG. Much like a Global Positioning Satellite receiver uses numerous satellites to determine our location on earth, we can use LORETA to detect the location of the brain's EEG generators more specifically.
Brodmann areas refer to very specific areas within the cortex that have specific functions or participate in a network to accomplish an activity. They are defined by their very specific cellular pattern. These areas are numbered and their function will be described in your report.
A LORETA image looks like this:
How does a QEEG relate to symptoms and concerns?
You might already be getting a sense of how these maps relate to you. Here's the nutshell: when parts of the brain either under-cooperate or over-cooperate, the body and brain attempt to regain a balance. This can be caused by lots of things -- illness, genetics, stress, trauma -- or a combination. Everyone is unique.
Symptoms and illnesses result from either the body's inability to adapt or rebalance itself, or as a consequence of over-compensation. An example of this is when an individual with memory and attention problems also has issues with anxiety -- which ultimately arises due to stress caused by not being able to remember or pay attention in the first place!
The firing speeds of neurons discussed above can tell us something about your state. If you're under-aroused or have a good deal of trouble paying attention, you may have too much neuronal firing in the theta range in certain areas of your brain. If you're anxious, you may have too much neuronal firing in the high beta range in certain areas of your brain This will be explored in your report and with the help of your therapist. In addition, please see the references at the bottom of this report for resources to learn more about specific EEG findings and their relation to function.
Other areas outlined in the report include the quality and characteristics of the raw EEG. Some examples may be "low voltage fast," "slowing" or "disorganized." These also tell a clinician a bit about your level of alertness or proneness to anxiety or inattention.
Here's the good news: not every QEEG finding is a problem. For example, individuals who are public speakers might have an excess of activity in speech output areas of the brain. Executives may have excessive beta activity in the frontal and central areas because they have developed the ability to focus intensely. Those are gifts and skills.
You and your therapist will sort out which functions work for you and when, and which ones do not. Based on your unique brain function and concerns, certain therapies might be recommended for you, such as neurofeedback, biofeedback, home-based practice, psychotherapy or medical intervention.
Keep in mind the goal is not to eliminate the unique characteristics of your brain's function, but to help build a more flexible, resilient response. For instance, an executive who needs to pay intense attention in the board room might find that intensity creates anxiety and sleeplessness at home. She or he needs to learn to shift from that "always on" state.
The goal of neurofeedback is to de-emphasize old neural pathways and restore proper sequencing of neural events.
For instance, when we excessively ruminate or become distractible often, our brain responds by creating its own version of a well-trodden trail in the form of reinforcing and building numerous neural pathways that support the behavior. That's why when we spend a good deal of time depressed, anxious or angry, we seem to be able to become depressed, anxious or angry more easily. Our brain is adept at remembering the way!
We can retrain not only through neurofeedback, but also through constantly practicing our preferred behavior and by learning skills to help us in that endeavor. Biofeedback, cognitive-behavioral therapy, meditation and mindfulness training are also useful in these areas.
Neurofeedback also encourages communication between cortical and sub-cortical structures, as well as different cortical regions of the brain. It helps re-establish the rhythmic patterns of the EEG (by regulating thalamic firing) and encourage internal self-regulation and choice. Ultimately, it is a therapy that encourages more efficiency and balance. Similarly biofeedback creates balance and has an impact on the brain's balance through the body.
Neurofeedback is considered a "top-down" intervention because it encourages cortical regulation, which influences other body and brain processes. By contrast, biofeedback exerts influence on the body and in turn the regulatory processes within the brain stem, which network with the cortex.
How much research does QEEG, neurofeedback and biofeedback have?
A search of PUBMED, the National Library of Medicine's research database yields over 450 reviews of QEEG. Specific concerns -- such as depression and QEEG -- can also be researched. Neurofeedback and related search terms provide 3,877 reviews. Biofeedback (which also may include neurofeedback) results in 8658 reviews.
The bottom line is that more research is found than can be reviewed in this short summary, and it's growing daily. At the end of this paper, you'll see several references in case you want to read more about QEEG, neurofeedback or biofeedback.
Some helpful websites to access more information include the International Society for Neurofeedback and Research (www.isnr.org), the Association for Applied Psychophysiology and Biofeedback (www.aapb.org), the Biofeedback Certification International Alliance (www.bcia.org) and the EEG and Clinical Neuroscience Society (www.ecnsweb.com).
A QEEG doesn't diagnose, but it can help you gain insight about how you function and help you and your therapist decide on appropriate therapies. When you do use therapies to balance your body and brain, you might be in a better position to address your concerns.
Your QEEG report will contain some ideas and suggestions. Through research, you may find some of your own as well. Please be sure to critically evaluate the research and discuss these with your therapist and other health care practitioners to make sure they complement your present treatment.
Finally, the choice to find health and balance is difficult at best under the present pressures and stresses of our society, but well worth it. Change might include difficult choices and departures from the expectations of others. Congratulations on your efforts and best of luck in your endeavors!
Thank you for allowing me to share some information with you on QEEG.
Linda A. Walker, MHR, LPC, BCN, BCB
Inland Seas Neurotherapy and Counseling
Adjunct faculty, Western Michigan University
ISNR Comprehensive Neurofeedback Bibliography:
What is QEEG/brain mapping?: http://qeegsupport.com/what-is-qeeg-or-brain-mapping/
Budzynski, Thomas H.; Budzynski, Helen K.; Evans, James R.; and Abarbanal, Andrew (2nd ed. 2009). Introduction to Quantitative EEG and Neurofeedback:
Advanced Theory and Applications. Burlington, MA: Elsevier.
Gunkelman, Jay (Fall 2006). Transcend the DSM Using Phenotypes. Biofeedback. 34 ( 3) 95-98.
John ER, Prichep LS, Almas M. (1992). Subtyping of psychiatric patients by cluster analysis of QEEG. Brain Topography. 4, 21-326.
Kaiser, David A. (2006). What is QEEG? Journal of Neurotherapy, 10(4)37-52.
Prichep LS, John ER. (1992). QEEG profiles of psychiatric disorders. Brain Topography. 4, 249- 257.
Schomer, Donald L., Lopes da Silva, Fernando H (Eds.) (Sixth Ed, 2011). Niedermeyer's Electroencephalography: Basic Principles, Clinical Applications, and
Related Fields. New York: Lippincott Williams & Wilkins.
Thatcher, R.W.; Walker, R.A.; Biver, C.J., North, D.M. and Curtin, R. (2003). Normative Database: Validation and Clinical Correlation. Journal of Neurotherapy.
Yucha, C., & Gilbert, C. (2008). Evidence-based practice in biofeedback and neurofeedback. Wheat Ridge, CO: Association for Applied Psychophysiology and
A representation of pyramidal cell interaction in the human brain. Pyramidal cells are a type of neuron found in the cortex and are responsible for producing the electrical activity recorded in the EEG
The brain's general functional divisions
Cortical Functions, Transcranial Technologies, 2012