Updated: Sep 25, 2019
In a neurofeedback evaluation, sensors are placed at various points around the head and brain activity is measured. These readings will allow us to see whether there are excesses and/or deficiencies of delta, theta, alpha, or beta brainwaves either globally or in particular areas of the brain. With this information we can then create a protocol that responds to the client's personal goals.
When attaching sensors to the head, I first need to clean the areas where they'll be attached. Our first two sensors will be placed on the earlobes and we need to prepare the skin by rubbing them with a slightly abrasive cream- this doesn't hurt at all but can feel cold at first (and it is certainly weird having someone rubbing your earlobes!). Once the skin is prepared, I then add a conductive paste to the sensors and clip them onto each earlobe. The sensors on the ears are used to filter out unwanted information; they will remain in place throughout the whole evaluation.
The two remaining sensors to be placed are the ones that will provide the information we need for the evaluation. For placing these sensors, the scalp is cleaned and prepared with the abrasive cream and the conductive paste put on the sensors and stuck to the head. Once the sensors are in place, I then check for impedance to ensure we are well connected and getting an accurate reading. If the sensors are well connected we can proceed with the readings, but if they're not, I need to make adjustments and this can take a few minutes, especially when there is a lot of hair involved.. If the client is bald, this process will take far less time!
The system that I use has two sensors for measuring brain activity. Since we want to read what is going on in ten key areas of the brain, the sensors are re-positioned five times in order to measure all ten areas.
Each placement corresponds to an area of the brain associated with particular functions. In the picture above, I am performing the final reading on the parietal and occipital areas (Pz and Oz). For each reading, the client must stare at an assigned focal point in the room and remain as still as possible for 2 minutes at a time.
Once the readings are done for all ten areas, all the sensors are removed, the pastes and creams are wiped off the skin and hair, and some hairstyling happens so that the client can leave looking somewhat like they did when they arrived! The process takes between 60-80 minutes depending on the client.
After the session, I then go through the data and remove any artifacts like blinking or muscle tension, this can be tedious or fairly straightforward depending on how easily it was for the client to sit still. When I've gathered all my clean data, I can then create graphs that allow me to see if and where there is an imbalance that might be related to the client's issues.
Below, you will see the graphs of a client (used with permission) who has been dealing with issues with concentration since childhood. The norm would be to have a ski slope trajectory, but here we see that between 3-5Hz the lines start moving upward and then start decreasing again after about 7Hz. This increase shows that the client has an excess of the slow brain wave known as theta. Individuals with ADD or ADHD often have an excess of theta, so this fits with the clients complaints of having difficulty focusing.
Once I've gathered my findings, I am then able to outline a preliminary protocol which I then discuss with my supervisor- a psychologist and highly experienced neurofeedback practitioner who works for the Institut Neurosens where I did my training. He runs the data through a database that can give us a better visual on how the client compares to the norm for his or her age. Below you will see the qEEG brain mapping results for the same person as above. The blue lines that you see around the edges should be ignored as we don't gather data for that area, what is of interest here is the red areas in the frontal and central parts of the head, especially on the left side signifying that there is an excess between 3 and 7Hz (theta waves).
For this case, the qEEG view confirms that the excesses seen in the original graph go beyond the norm for the population and that this is indeed the most important area to train.
The evaluation process fascinating for both the client and practitioner. As a practitioner, combining what is known about the different areas of the brain and piecing it together with the client's issues and intended outcomes is exhilarating. For clients, it's a unique opportunity to view what is happening with our most important organ in the body, and this helps to separate the brain from the person. This new perpective can off-load some of the guilt and frustration that people often carry when dealing with behavioural and health issues, and finally a path to self-improvement can feel within ones reach.