Some people have to see it to believe it. Concussions are perplexing to them. There is nothing to see. Diagnoses are based on subjective first-hand reports rather than “objective” testing.
Brain cells communicate with each other through electrical impulses.
These impulses can be recorded by an electroencephalogram (EEG). It’s sometimes called a “brain wave test.”
An EEG uses electrodes placed on a person’s scalp to detect electrical activity in that person’s brain.
The electrodes collect the brain’s electrical activity. This electrical activity is displayed as patterns of brain waves on a screen. This collection of the brain activity waves is known as an EEG “tracing.”
The EEG tracing is reviewed, manually and automatically, to remove unwanted artifacts like waves identifying eye blinks. The EEG tracing can be analyzed for irregular brain activity such as seizures or encephalitis. The use of EEG to ascertain a brain’s electrical activity has been in use for nearly 100 years.
qEEG (quantitative EEG) is the application of digitization to the basic “brain wave” test (electroencephalogram (EEG)).
qEEG analyzes the EEG tracing data. The quantitative analysis of an EEG tracing examines the function of a person’s brain. qEEG also produces a “brain electrical activity map.”
The examiner compares the subject’s EEG tracing to a normative database. That way the qEEG of the examinee can be compared to known clinical populations.
Here’s an important point: qEEG is not a stand alone diagnostic tool. A MTBI diagnosis is a prerequisite to the clinical use of qEEG.
qEEG provides a method of identifying brain functional abnormalities. These can then be correlated with neuropsychological test findings.
qEEG adds to the “convergent validity” of the forensic determinations made by neuropsychologists and other providers.
It also allows doctors to show—in a very graphic way—the differences between the injured person’s brain activity and “control” groups.
Studies show a very low error rate of qEEG in assessing TBI in the clinical context. A 2001 study found accuracy over 95% for classification of TBI. Similarly, a 2004 study found qEEG to be highly sensitive (96%) in identifying post-concussive syndrome.