qEEG


With a qEEG (quantitative electroencephlagram), your brain can be mapped in terms of the electrical power at numerous sites on your scalp and the connections between those sites. The results can be compared to norms and, using symptom questionnaireS, it can be determined what needs adjustment. Using computer displays and sound systems, you (more accurately, your brain) can be guided to greater balance and improved functionality.

Raw EEG

The display on the left shows a short segment of the raw EEG recorded at 19 channels. A skilled observer can tell what kinds of brain waves are exhibited. Typically two resting-state conditions are recorded–eyes open and eyes closed–for approximately 5-10 minutes each. The recording is then examined for artifacts such as eye movement, jaw clenching, movement and so on. These artifacts need to be taken out of consideration since they are not EEG. In order to do mapping, at least one minute of “clean” EEG with no artifact is required.  Reliability criteria must also be met. The clean recording is then analyzed and compared to a normative database consisting of individuals of the same age. The normative database consists of individuals with no history of psychiatric illness or head injury and average to above average intelligence. It really isn’t representative of the general population but of more high functioning individuals. 

Brain map–summary

The map on the right summarizes an eight minute recording in the eyes closed condition that has been compared to the normative database. It shows the absolute and relative power in each of the bands and the connections between the 19 sites in terms of amplitude asymmetry, coherence and phase from Delta (very slow waves) to High Beta (very fast waves). Hot colors (red, orange and yellow) indicate higher than average values, whereas cold colors (dark and light blue) indicate lower than average values. Green indicates “normal” values.

This individual exhibits a high concentration of absolute power in the Theta and Alpha bands. Relative power shows how the brain allocates resources. Most of this individual’s brain’s resources are allocated to the Alpha band. Asymmetry is shown in the Theta and High Beta range. High coherence (the degree to which sites are associated or coupled) is shown in the Theta and Alpha bands. Phase Lag (the degree to which a wave is behind another wave of the same frequency in time) is most apparent in the Theta band.

This map is from a recording of a Buddhist monk who had been meditating for over 30 years. It illustrates the point that  sometimes skills show up as “abnormalities.” These maps are not diagnostic and need to be compared to symptoms to determine whether we are looking at a highly developed skill or a problem that needs to be remedied. This is why we use symptom checklists to determine what are the problems that need to be addressed. Based on the checklists, we can generate hypotheses regarding what the actual map should look like. We then compare the hypothetical map with the actual map to determine what needs to be addressed.