Articles

It is an accepted phenomena in medicine and neuropsychology that traumatic injury to the brain (TBI) can and does cause lasting, adverse changes in the functioning of the mind and subsequently reduced efficiency in every day life. There has been an increasing interest in understanding and evaluating post TBI impairment relative to neuropsychological test scores, symptom reports, symptom severity and diagnoses. Researchers have demonstrated that although the majority of individuals experiencing mild head injury have been found to remit in their symptoms and impairments and improve to near or at pre-trauma level within a year’s time, it has always been recognized that a small group of individuals appear to not recover very well. The reasons for their failure to recover has still not been well understood. It appears that this small group, perhaps 10% to 15% of individuals experiencing even mild TBI do not recover at a normal rate and experience functional impairment long after there are any measurable or demonstrable signs of medical problems. Often these individuals suffer from accompanying chronic pain and post accident psychiatric problems as well as pre-accident problems.

Further a collection of post-concussive syndrome symptoms, including problems with thinking, physical impairments involving fatigue, dizziness, headache and sensory sensitivity as well as mood changes, occur in up to 80% of individuals during an acute period following a mild head trauma. Approximately 50% of affected individuals experience symptoms for at least three months with as noted 10% to 15% complaining of persistent post-concussive symptoms beyond that period. PCS symptoms overlap with other physical and psychological conditions making accurate assessment, interpretation and litigation difficult. Post-concussive symptoms are reported by some adults with no history of head trauma or other neurological illness. Taken in combination, these studies suggest, for example, that individuals seeking psychotherapy report as many if not more post-concussive symptoms than individuals without medical problems or those seeking help for other medical issues. These studies reveal that the frequency, intensity and duration of post-concussive symptoms were often correlated positively with daily stress. For example, individuals suffering from depression, even those with no established health problems, often report more frequent and more severe health symptoms than those who are not depressed. This appears true for a wide range of symptoms, including those that do not appear in any logical way related to the depression.

It remains to be determined whether affective changes following head injury, such as those related to depression might be the result of neurologic impairment combined with chronic pain and lifestyle change. Very clearly, additional research needs to be conducted and will be over the coming ten years. However, in the interim, as I have advised in past Legal Updates, the prudent, science based forensic neuropsychologist must provide a reasoned and reasonable theory of etiology when evaluating individuals experiencing chronic symptoms of minor closed head injury presenting chronic pain accompanied by psychiatric changes including depression and anxiety.

One of the most complex questions facing medical professionals and neuropsychologists is the matter of estimating pre-trauma levels of functioning. Recently, authors Rel Lange, Grant Iverson and Alice Rose in Vancouver, Canada addressed this issue examining post-concussion symptom reporting on what they refer to as the “good old days” bias following mild TBI. The sample consisted of individuals with hospital based concussions who were then evaluated a number of months post-injury. Patients provided retrospective pre-injury symptom ratings. The researchers compared them with a sample of healthy controls recruited from the community and a local university. Those with TBI reported a high level of pre-injury functioning. Individuals currently in litigation reported even more post-injury symptoms than controls. However, litigation status was not associated with self-reported, pre-injury retrospective ratings consistent with the “good old days” bias. It appears that patients with mild TBI misperceive their pre-injury functioning as better than the average person. This finding is consistent with the very few studies examining a similar pattern of bias. While this research requires replication, it still does not allow a confident conclusion as to whether the “good old days” bias, a social-psychological phenomena is in fact operative in most cases. These types of studies do not allow researchers to differentiate presumably subconscious recall bias from the deliberate under-reporting of past symptoms. Nevertheless, the “good old days” bias can potentially have a major negative impact on a patient’s perception of current problem severity and mis-attribution of most or all current symptoms and problems to a current injury and to the duration of recovery from injury.

To further address this issue, my colleague, Jack Naglieri, and I have been collecting reports of impairment in the general population. Our initial pilot of 400 adults reveals that most adults report some level of impairment in every day life independent of medical problems or other adversities. We are collecting standardization samples representative of the general population across age, geographic location, cultural and ethnic background and socio-economic status in an effort to provide a firm, baseline foundation of functioning in impairment in the general population by age and gender. Until such data are available the debate often generated between opposing forensic experts in litigation issues concerning etiology will likely continue.