Wiley Mittenberg

Base rates of malingering and symptom exaggeration

Base rates of probable malingering and symptom exaggeration are reported from a survey of the American Board of Clinical Neuropsychology membership. Estimates were based on 33,531 annual cases involved in personal injury, (n = 6,371), disability (n = 3,688), criminal (n = 1,341), or medical (n = 22,131) matters. Base rates did not differ among geographic regions or practice settings, but were related to the proportion of plaintiff versus defense referrals. Reported rates would be 2-4% higher if variance due to referral source was controlled. Twenty-nine percent of personal injury, 30% of disability, 19% of criminal, and 8% of medical cases involved probable malingering and symptom exaggeration. Thirty-nine percent of mild head injury, 35% of fibromyalgia/chronic fatigue, 31% of chronic pain, 27% of neurotoxic, and 22% of electrical injury claims resulted in diagnostic impressions of probable malingering. Diagnosis was supported by multiple sources of evidence, including severity (65% of cases) or pattern (64% of cases) of cognitive impairment that was inconsistent with the condition, scores below empirical cutoffs on forced choice tests (57% of cases), discrepancies among records, self-report, and observed behavior (56%), implausible self-reported symptoms in interview (46%), implausible changes in test scores across repeated examinations (45%), and validity scales on objective personality tests (38% of cases).

Changes in cerebral functioning associated with normal aging

It has been suggested that the normal aging process is characterized by a pattern of neuropsychological performance decline that implies relatively greater vulnerability of right-hemisphere functions. This hypothesis was tested in a sample of 68 volunteers aged 20-75 who were free of systemic and neurologic illness. Neuropsychologic measures of lateralized and focal function were specifically selected to eliminate systematic procedural differences among tests (e.g., timed vs. untimed, overlearned vs. unfamiliar). Inferences about the localizing significance of each measure were based on previously demonstrated double dissociation of function in lesion studies. Results suggested that declines in cerebral efficiency are not differentially lateralized. Age correlated performance changes implied bilateral reduction that was significantly more pronounced on operations associated with frontal-lobe function. Anatomic and theoretical explanations for this pattern were discussed.

Treatment of Post-Concussion Syndrome Following Mild Head Injury.

Approximately 38% of patients who sustain head trauma characterized by a brief disturbance of consciousness and clinically unremarkable neuroradiologic findings meet International Classification of Diseases 10th edition (ICD-10) diagnostic criteria for postconcussion syndrome (PCS). Physicians treat a majority of cases with nonsteroidal analgesics or antidepressants, and refer about 40% for psychological consultation. Psychological treatment typically involves education, reassurance, and reattribution of symptoms to benign causes. A review of controlled treatment outcome studies conducted over the past 2 decades in Scandinavia, Great Britain, Canada, and the United States suggests that early single session treatment can prevent the syndrome as effectively as traditional outpatient therapy. Several standardized, empirically supported treatment manuals are available.

Mood and Anxiety disorders following pediatric traumatic brain injury: A prospective study

Studies utilizing standardized instruments for assessing mood and/or anxiety disorders following pediatric traumatic brain injury have seldom been reported in the literature. Previous reports have largely focused on cognitive impairment, behavioral dysfunction, or adaptive functioning, and have typically relied on parental informants. In this study, children hospitalized for mild (N = 42) and moderate/severe (N = 19) brain injury were assessed 6-months postinjury using the Anxiety disorders Module A and the Mood disorders Module C of the Diagnostic Interview Schedule for Children – IV Revision (DISC-IV). The data collected for the brain injury groups were compared to an orthopedic control group (N = 35). The relationship between a new onset mood and/or anxiety disorder (NOD) and injury severity indices was examined. Sequential logistical regression was also utilized to examine the impact of a brain injury, demographic variables, preinjury psychiatric disturbance, development disorders, litigation status and postinjury environmental stress on emotional outcome. Results indicated a relationship between brain injury and NOD. Multivariate analysis demonstrated that postinjury level of stress and severity of brain injury were the most robust predictors of NOD, accounting for 23% of the variance in the model. These results support the premise that the development of a mood and/or anxiety disorder following pediatric head injury is mediated by multiple determinants. The findings suggest that early psychosocial assessment and interventions aimed at increasing a childs coping may attenuate the emotional consequences of pediatric brain injury.

Intrasubtest Scatter on the WAIS-R as a Pathognomonic Sign of Brain Injury

Patterns of intrasubtest scatter on the Wechsler Adult Intelligence Scale-Revised were compared among patients with closed head trauma, patients with focal cerebral lesions, and neurologically normal controls. Interpretive guidelines are suggested for future clinical cross-validation