Whiplash Injury

EEG, Whiplash and Mild Head Injury

A great deal of research time has been spent on finding an objective tool that can be used to state for certain whether a whiplash patient has a legitimate injury. The value of such a test is obvious, but has proven elusive.

Two different groups of researchers have recently investigated the utility of EEGs in diagnosing objective signs of psychological distress after whiplash and mild head injury. This new work adds to previous study by Packard and Ham, who wrote that EEGs "can be clinically useful in assessing and detecting cognitive dysfunction in patients sustaining mild head injury and reporting difficulties with concentration and/or memory."1

The first study2 was done by a group of Dutch researchers who compared 40 whiplash patients to 12 mild head injury patients, 10 tension headache patients, and 19 asymptomatic control subjects. All subjects were given an EEG exam, and some of the whiplash patients and asymptomatic subjects were also given a P300 test. The P300 is an EEG exam that can be used to measure attention and concentration. P300 abnormalities have been found in PTSD patients and patients with anxiety or depression.

The researchers found that conventional EEG showed no significant differences between the three patient groups, but there were significant differences between the patient groups and the asymptomatic control subjects. The authors conclude that EEG differences "could be related to cognitive/emotional disabilities in post-traumatic patients and perhaps chronic pain may contribute to the EEG findings."

The second study3 looked at the relationship between mild head injury, stress, and the P300 component. The authors state their objective as such: "The P300 component of event-related potentials is affected by personal meaningfulness of the stimulus to the subject. Thus the P300 component could provide an objective parameter in the emotional assessment of road accident mild head injury patients, when exposed to relevant stimuli."

The study examined 13 patients with post-traumatic head injury and 14 healthy control subjects. P300 was measure during word tests; one set of words was accident-related, and the other set of words were "neutral" words.

The study found that the patients and controls differed significantly in their response to the different word types, and accident-related words resulted in a much larger P300 wave in post-traumatic patients. There was also a relationship between the objective EEG test and the patient’s anxiety level, as measure by the Zung State Anxiety test.
The authors conclude:

"None of the new brain imaging techniques nor quantitative EEG analyses have proved useful enough in the assessment of mild head injured, as well as whiplash, patients. Thus, in most cases diagnosis relies solely on the history given by the patient, who is often biased toward reporting more intense symptoms by the achievement of secondary gain. The present study suggests an objective neurophysiological parameter, the P300 wave, as a possible diagnostic tool for the situation."

  1. Packard RC, Ham LP. Evaluation of cognitive evoked potentials in post-traumatic headache cases with cognitive dysfunction. Headache Quarterly 1996;7(3):218-224.
  2. Viana PC, Barreira AA, Lopes FH, et al. Neurophysiological and neuropsychological studies on post-whiplash and minor head injury patients. Proceedings from the 1999 World Congress on Whiplash-Associated Disorders, p. 153.
  3. Granovsky Y, Sprecher E, Hemli J, Yarnitsky D. P300 and stress in mild head injury patients. Electroencephalography and Clinical Neurophysiology 1998;108:554-559.

 

Please note that this article is copyrighted and may not be reproduced without permission. To include our articles and videos on your website, check out our chiropractic website service.