QUANTITATIVE EEG BRAIN MAPPING
Trying to describe a dynamic, complex, chaotic system like a brain with static numbers is like trying to describe a 30-minute sunset with a snapshot. Nevertheless, measuring the ebb and flow of energy in the brain’s electrical domain across time and under various conditions remains the best option for creating a uniquely tailored map of each individual brain.
While a standard electroencephalogram (EEG) used by neurologists measures small electrical discharges in the brain as a means of identifying the presence of seizure activity, a quantitative EEG (QEEG) conducts numerous calculations in order to provide a much more rounded map of brain activity. Data are generally recorded from 20 or more standard EEG sites on the head during eyes closed, eyes open and task conditions. The result is a picture of how brain activation changes from resting to awareness to active processing states with the data being presented in terms of the main measures of brain activity: frequency, amplitude, stability, and connectivity.
There are two main approaches to looking at all this data:
Population-based: Compares hundreds of measures from the client against a database of people recorded over the past 30 years to produce dozens of “Z-scores” — specific measures in specific areas of the client’s brain which differ from “average”. Whether these differences are positive or negative, adaptive or mal-adaptive is not clear.
Pattern-based: Identifies stable activation patterns that have been linked in QEEG research to problem areas in a person’s life. These were developed by comparing people with specific issues (e.g., anxiety, ADHD) against the population to see where they reliably differ. If a pattern present in the brain is consistent with areas in which you would like to see change or improvement, then training the brain to change that pattern using neurofeedback can be expected to result in changes to the mood, behaviour, performance, or symptom of concern.
While population-based QEEGs are great for group research, they may not be so helpful when it comes to the individual. They can’t distinguish between functional and problematic variances, so they risk training down the client’s strengths when used to generate neurofeedback brain-training protocols. The notion of training everyone towards the average of a particular group is fine if you're below average but may be not so good if you’re on the other side of the equation. And who wants to be average anyway?
Accordingly, we use the pattern-based approach with the aim of developing an individually tailored whole-brain training plan that will address your areas of concern, maximise your unique potential, and get you into a flow state more quickly, more often. And while QEEGs are generally used for designing neurofeedback training protocols, they are also a valuable means of evaluating treatment effectiveness for any number of interventions such as medication, supplements, meditation, or other therapy regimes by utilising pre- and post-treatment brain maps. They also satisfy the curiosity of those who simply want to know what’s going on in their engine room. After all, you wouldn’t send your car to a mechanic who didn’t at least check under the bonnet.
BRAIN PATTERNS ON THE QEEG
Below are some examples of brain patterns that may be seen on a QEEG:
GREY MATTER HEAD INJURIES
Grey-matter injuries kill neurons. Most immediately the brain shows lower amplitudes in all frequencies. The brain replaces these neurons over time, but the new neurons may not re-form the connections of those which are lost. Result: a spike in Alpha brain wave activity that does not go away with eyes open or at task.
FAST-BRAIN PATTERN
Fast-brain patterns can be related to stressed, anxious, angry, obsessive states — being stuck in “fight-or-flight”. Because this brain burns so much energy, even at rest, adrenal fatigue, low energy levels and depression can result as well. The hotter the brain is on the right hemisphere and/or right-rear quadrant, the more problematic.
WHITE MATTER HEAD INJURIES
White-matter injuries tear axons, breaking neuronal connections. The neurons keep firing, but they can’t receive or pass along signals, so they pulse at the Delta rhythm. White matter cannot be repaired. Result: a spike in Delta brain wave activity that does not go away with eyes open or at task.
SLOW-BRAIN PATTERN
Slow-brain patterns may be depressed, inattentive, dreamy, have difficulty processing language or working with sequences and hierarchies. When the brain de-activates (gets slower at task) it is metabolically unable to sustain higher energy states involved in processing.
BURNED OUT ANTERIOR CINGULATE
The Anterior Cingulate is involved with motivation and it is the spigot that controls the flow of emotions from the limbic system to the prefrontal cortex. When emotional drive is very strong — or the brain’s strategy is to deny feelings — the cingulate has to work very hard, but we often see it nearly shut down after years of over-use. The result can often be obsessive thoughts or compulsive behaviour and, for some people, can extend to the need for sameness, routine and ritual, fear of change, lining up objects, etc. Anything to control emotional overdrive.