Neuropsychological, functional, and behavioral outcome in South African traumatic brain injury litigants

The neurocognitive profile of post-traumatic stress disorder (PTSD), major depressive disorder (MDD), and PTSD with comorbid MDD

OBJECTIVE

Neurocognitive dysfunction has been associated with post-traumatic stress disorder (PTSD) and major depressive disorder (MDD). However, although PTSD is often comorbid with MDD, there is little neurocognitive work to date on individuals who suffer from both PTSD and MDD. Here, we compared neurocognitive domains in individuals with PTSD, MDD, and comorbid PTSD and MDD with those of healthy controls.

METHODS

Participants comprised of mothers enrolled in the Drakenstein Child Health Study, a study exploring child health determinants in the Drakenstein district, Western Cape. N = 175 mothers (between 18 and 50 years) were recruited and divided into 4 groups: PTSD, MDD, PTSD with MDD, and healthy controls. Participants were assessed using the computerized NIH Toolbox, and paper and pencil neurocognitive tests. Domains assessed included executive function, memory, attention, learning, and processing speed.

RESULTS

Distinct patterns of neurocognitive dysfunction were observed in this sample. PTSD was associated with more intrusion errors and MDD was associated with delayed recall impairment, relative to healthy controls. PTSD with comorbid MDD was associated with processing speed impairments, relative to healthy controls, and monodiagnostic groups. No group differences were observed on measures of attention and executive function.

CONCLUSION

Distinct patterns of neurocognitive dysfunction were associated with diagnoses of MDD and PTSD. Greater anticipated dysfunction and impairment in comorbid PTSD and MDD was not observed, however. Further work is needed to replicate and extend these findings.

Length of post-traumatic amnesia and its prediction of neuropsychological outcome following severe to extremely severe traumatic brain injury in a litigating sample

Primary Objective: The aim of the current study was to examine the relationship between duration of post-traumatic amnesia (PTA) and neuropsychological outcome at one or more years following severe to extremely severe traumatic brain injury (TBI) in a litigating sample. Research Design: Retrospective study design, using data collected from 2010 to 2017. Methods and Procedures: Data from 41 cases obtained from a private medicolegal neuropsychological database was examined. The database comprised information pertaining to TBI etiology, TBI severity parameters, demographic variables, neuropsychological test results and scores on psychological questionnaires. PTA duration was examined as a continuous variable. All cases that demonstrated non-credible effort were excluded. Main Outcomes and Results: Continuous PTA duration was not found to be a significant predictor of cognitive impairment across domains of verbal intellect, non-verbal intellect, working memory, information processing speed, immediate memory, delayed memory, and executive functioning. Conclusions: The predictive relationship between duration of PTA and cognitive impairment that has been reported in non-litigating populations did not exist in a litigating TBI sample. Findings illustrate the importance of investigating the relationships between injury variables and cognitive outcome in a population undergoing litigation, to provide better understanding of outcome in this subgroup of patients with TBI.

Assessment of feigned cognitive impairment in severe traumatic brain injury patients with the Forced-choice Graphics Memory Test

INTRODUCTION

The Forced-choice Graphics Memory Test (FGMT) is a newly developed measure to assess feigned cognitive impairment. This study investigated the ability and reliability of FGMT for identification of malingering in patients with traumatic brain injury (TBI).

METHODS

The FGMT was administered to 40 healthy volunteers instructed to respond validly (Healthy Control, H-C), 40 healthy volunteers instructed to feign cognitive impairment (Healthy Malingering, H-M), 40 severe TBI patients who responded validly (TBI control, TBI-C), and 30 severe TBI patients who evidenced invalid performance (TBI malingering, TBI-M).

RESULTS

Both malingering groups (H-M and TBI-M) performed much more poorly than the nonmalingering groups (H-C and TBI-C). The FGMT overall total score, score on easy items, and score on hard items differed significantly across the four groups. The total score showed the highest classification accuracy in differentiating malingering from nonmalingering. A cutoff of less than 18 (total items) successfully identified 95% of TBI-C and 93.3% of TBI-M participants. The FGMT also demonstrated high test-retest reliability and internal consistency. FGMT scores were not affected by TBI patients' education, gender, age, or intelligence.

CONCLUSION

Our results suggest that the FGMT can be used as a fast and reliable tool for identification of feigned cognitive impairment in patients with TBI.

Neuropsychology in South Africa: confronting the challenges of specialist practice in a culturally diverse developing country

OBJECTIVE

This was an invited paper on the history and current status of neuropsychology in South Africa.

METHOD

Information was gathered from literature searches, personal communication, and the authors' experiences while occupying relevant professional and academic positions for over 30 years.

RESULTS

Since its origins in the 1950s, the development of neuropsychology in South Africa has faced numerous challenges, against a background of extreme sociocultural and socioeconomic disparity in the country that is on-going. The creation of the South African Clinical Neuropsychological Society in the 1980s, a credentialing and training body, gave impetus to the discipline. In the absence of a neuropsychology category within the South African professional framework, university instruction has been ad hoc with vastly different levels of competency depending on the institution involved. The small number of practitioners and/or academics involved in neuropsychology includes mainly masters, and some doctoral level psychologists registered in clinical, counseling or educational categories. A prime emphasis of neuropsychological research has been local norming of psychometric tests to facilitate valid assessment practices in the country. South Africa is on the cusp of achieving a hard-won neuropsychology professional register. It is anticipated that this development will provide impetus to the discipline by promoting training programs, the creation of neuropsychology posts, wider service delivery, and increased research funding.

CONCLUSIONS

Despite significant challenges in a culturally diverse, developing country, neuropsychology has evolved sufficiently to warrant the creation of a separate category in the professional framework. This development will facilitate training, research, and services in the country.

Factitious disorders and malingering in relation to functional neurologic disorders

Interest in malingering has grown in recent years, and is reflected in the exponential increase in academic publications since 1990. Although malingering is more commonly detected in medicolegal practice, it is not an all-or-nothing presentation and moreover can vary in the extent of presentation. As a nonmedical disorder, the challenge for clinical practice remains that malingering by definition is intentional and deliberate. As such, clinical skills alone are often insufficient to detect it and we describe psychometric tests such as symptom validity tests and relevant nonmedical investigations. Finally, we describe those areas of neurologic practice where symptom exaggeration and deception are more likely to occur, e.g., postconcussional syndrome, psychogenic nonepileptic seizures, motor weakness and movement disorders, and chronic pain. Factitious disorders are rare in clinical practice and their detection depends largely on the level of clinical suspicion supported by the systematic collection of relevant information from a variety of sources. In this chapter we challenge the accepted DSM-5 definition of factitious disorder and suggest that the traditional glossaries have neglected the extent to which a person's reported symptoms can be considered a product of intentional choice or selective psychopathology largely beyond the subject's voluntary control, or more likely, both. We present evidence to suggest that neurologists preferentially diagnose factitious presentations in healthcare workers as "hysterical," possibly to avoid the stigma of simulated illness.

Four-hour delayed memory recall for stories: Theoretical and clinical implications of measuring accelerated long-term forgetting

It has been noted that clinical neuropsychological assessment is "blind" to certain abnormalities of consolidation that occur beyond standard 30-min delay intervals. For example, normal forgetting at 30-min delays has been followed by enhanced forgetting at longer delays in temporal-lobe epilepsy, termed accelerated long-term forgetting (ALF). To evaluate whether ALF could be identified in the neuropsychological assessment of a small sample of examinees with head injuries or other neurological diagnoses (n = 42), a 4-hr delayed recall condition was added to the Logical Memory subtest of the Wechsler Memory Scale-Third Edition. A small percentage of examinees (5/42 or 11%), despite exhibiting unimpaired story recall immediately and after 30-min delays, showed increased forgetting when compared with the average retention of stories (M = 0.83, SD = 0.17) after a 4-hr delay. Three of these 5 examinees also had impaired scores on 20-min delayed recall of the California Verbal Learning Test-Second Edition (CVLT-II) and would have been identified as having memory impairment without an extended, 4-hr delayed recall. In fact, the highest correlation among memory indexes was between 4-hr delayed recall of stories and delayed recall of the CVLT-II word list (r = .59, p < .0001), suggesting different consolidation rates for relational and nonrelational material.

Traumatic brain injury: guidance in a forensic context from outcome, dose-response, and response bias research

Traumatic brain injury (TBI) occurs at a high incidence, involving millions of individuals in the U.S. alone. Related to this, there are large numbers of litigants and claimants who are referred annually for forensic evaluation. In formulating opinions regarding claimed injuries, the present review advises experts to rely on two sets of information: TBI outcome and neuropsychological dose-response studies of non-litigants and non-claimants, and response bias literature that has demonstrated the relatively high risk of invalid responding among examinees referred within a secondary gain context, which in turn has resulted in the development of specific assessment methods. Regarding prospective methods for detecting possible response bias, both symptom validity tests, for measuring over-reporting of symptoms on inventories and questionnaires, and performance validity tests, for measuring insufficient effort on ability tests, are considered essential.