Quantitative Electroencephalography(QEEG)
QEEG is an accurate assessment procedure designed to measure the electrical activity of the cerebral cortex/brain. It aids in the diagnosis of brain dysfunction. Research has found that the QEEG is as reliable as other routinely used clinical tests.
QEEG is sometimes called brain mapping. A comprehensive 1999 literature review by Hughes and John in the Journal of Neuropsychiatry and Clinical neuroscience’s reported “of all the imaging modalities, the greatest body of replicated evidence regarding pathophysiological concomitance of disorders has been provided by EEG and QEEG studies.”
Brainwaves:
Brainwaves occur at a range of frequencies, some fast, some slow.
Delta brainwaves (below 4Hz) are the slowest, highest amplitude brainwaves and occur during sleep.
Theta brainwaves (4-8 Hz) have two patterns:
Theta (4-6 Hz) occurs in the state between waking and sleep. Theta (6-8 Hz) occurs with activity such as memory processing.
Alpha brainwaves (8-12 Hz) are associated with a state of relaxation.
Beta brainwaves (13-18 Hz) are associated with higher cognitive activity, attention and concentration.
Each individual always has some degree of each of these brainwave bands present in different regions of the cerebral cortex/brain.
If one is drowsy there are more delta brainwaves, if one is daydreaming there are more theta brainwaves. People with ADHD or head injuries have excessive slow wave activity. This leads to difficulties with attention, concentration, memory, impulse control and mood states.
QEEG Data Acquisition:
This procedure takes about a hour. It involves placing a snug cap on the head that contains sensors that measure the electrical activity coming from the cerebral cortex.
Information is gathered on brainwave patterns, interactions of different parts of the brain and the efficiency of the brain. This is done with the individual sitting quietly under the following conditions: eyes open, eyes closed and while reading or carrying out a cognitive task.
The QEEG data is then analysed, and imbalances or abnormalities in brainwave activity are noted. These become the focus of Neurofeedback Therapy which can help to re balance the brainwaves and alleviate the Central Nervous System dysfunction, so restoring, or producing best performance and function.
Research and Endorsements:
Since the 1990’s there have been hundreds of scientific articles documenting the usefulness of QEEG as an aid in the evaluation of conditions, such as mild traumatic brain injury, ADD/ADHD, learning disabilities, stroke and epilepsy. International Associations exist for professionals who use these procedures, including the Society of Applied Neuroscience (SAN) (www.applied-