Quantitative Electroencephalogram (QEEG), also known as a Brain Map, is a diagnostic technique in neurofeedback. An elastic net cap with 19 sensors on the head measures brainwave activity with no poking the skin or pain at all as the sensors barely touch the head. Brainwaves are recorded with eyes closed and with eyes open. This data is compared to one or more normative databases to determine if there are any findings for treatment. This guides the selection of neurofeedback protocols that are specifically designed to correct the brainwave dysfunctions identified. The QEEG may reduce the number of neurofeedback sessions necessary and increase the effectiveness of treatment.
Brain Maps guide efficient and effective treatment by guiding where the sensors should be placed and what frequencies should be addressed in training.
Understanding the numbers and graphics
The numbers generated are called Z scores which is a metric representing how normal or abnormal a score is in comparison to the Neuroguide Database. A Z score of +1 represents a score exceeding 84% of individuals that age; +1.25 exceeds 89%; +1.5 exceeds 93%; +2.0 exceeds 98%.
A combination of tables and graphics of Z scores appear below for either the traditional EEG bands (e.g. Delta 1-4 Hz.; Theta 4-7 Hz.; Alpha 8-12 Hz., Beta 12-25 Hz, etc.) or for specific single Hz. bins to enable increased precision.
The heads use colors to represent the Z scores at the 19 sites, with the nose on the top. Grey represents scores that are normal (+/- 1 Z score). The dots on the head are electrode sites (e.g. the top two being prefrontal sites)
Here is an example of three seconds of EEG recorded at 19 sites which shows the brain making normal brainwaves to start but then shifts into a dysregulated state where it makes the larger, slower brainwaves (theta). This dysregulated state is likely occurring when this ADHD child is inattentive.
ADHD Child’s EEG (8yrs old)
When this child’s recorded brainwaves are averaged and compared to a database we find that he is making more theta activity in the frontal and prefrontal sites is greater than 97% of children his age. This information can be represented in graphs as seen below.
We can see his excessive theta activity in the graph below:
An overanxious woman with a head injury has a different looking brainmap, showing the excessive delta and theta in the back of her head (at the site of injury), in addition to the excessive alpha everywhere.
Adult with Obsessive Compulsive Disorder
An adult suffering with severe Obsessive Compulsive Disorder has a QEEG which shows very excessive fast wave activity, a common pattern in OCD:
An adolescent with a severe seizure disorder (5x/week) had this QEEG before and after treatment:
Connectivity: A measure of how the various parts of the brain communicate with each other
Brainmaps provide a great deal of additional information in a variety of tables and graphs. In addition to measures of the power of the EEG at various speeds, the Connectivity measures give information about but about how well one part of the brain is communicating with another part of the brain.
This adolescent with ADHD and Obsessive Compulsive Disorder has difficulties with effective communication between various prefrontal and frontal lobe sites.