Assessment of performance validity in the Stroop Color and Word Test in mild traumatic brain injury patients: A criterion‐groups validation design

The current study assessed performance validity on the Stroop Color and Word Test (Stroop) in mild traumatic brain injury (TBI) using criterion‐groups validation. The sample consisted of 77 patients with a reported history of mild TBI. Data from 42 moderate–severe TBI and 75 non‐head‐injured patients with other clinical diagnoses were also examined. TBI patients were categorized on the basis of Slick, Sherman, and Iverson (1999) criteria for malingered neurocognitive dysfunction (MND). Classification accuracy is reported for three indicators (Word, Color, and Color–Word residual raw scores) from the Stroop across a range of injury severities. With false‐positive rates set at approximately 5%, sensitivity was as high as 29%. The clinical implications of these findings are discussed.     

Sensitivity and specificity of reliable digit span in malingered pain-related disability

The reliable digit span (RDS) performance of chronic pain patients with unambiguous spinal injuries and no evidence of exaggeration or response bias (n = 53) was compared to that of chronic pain patients meeting criteria for definite malingered neurocognitive dysfunction (n = 35), and a group of nonmalingering moderate-severe traumatic brain injury (TBI) patients (n = 69). The results demonstrated that scores of 7 or lower were associated with high specificity (> .90) and sensitivity (up to .60) even when moderate to severe TBI are included. Multiple studies have demonstrated that RDS scores of 7 or lower rarely occur in TBI and pain patients who are not intentionally performing poorly on cognitive testing. This study supports the use of the RDS in detecting response bias in neuropsychological patients complaining of pain as well as in the assessment of pain-related cognitive impairment in patients whose primary complaint is pain.     

Malingering in toxic exposure: classification accuracy of reliable digit span and WAIS-III Digit Span scaled scores

This study examined the sensitivity and false-positive error rate of reliable digit span (RDS) and the WAIS-III Digit Span (DS) scaled score in persons alleging toxic exposure and determined whether error rates differed from published rates in traumatic brain injury (TBI) and chronic pain (CP). Data were obtained from the files of 123 persons referred for neuropsychological evaluation related to alleged exposure to environmental and industrial substances. Malingering status was determined using the criteria of Slick, Sherman, and Iverson (1999). The sensitivity and specificity of RDS and DS in toxic exposure are consistent with those observed in TBI and CP. These findings support the use of these malingering indicators in cases of alleged toxic exposure and suggest that the classification accuracy data of indicators derived from studies of TBI patients may also be validly applied to cases of alleged toxic exposure.     

Adult attention-deficit/hyperactivity disorder: neuropsychological correlates and clinical presentation

We compared the neuropsychological test performance of adult ADHD patients to the neurocognitive profiles of control subjects recruited from the general population. We administered a neuropsychological test battery consisting of measures considered sensitive to either orbitofrontal or dorsolateral-prefrontal (DLPF) dysfunction. Orbitofrontal hypoarousal is associated with behavioral disinhibition and a relative indifference to punishment. The DLPF region may function as a central executive system. Indeed, DLPF dysfunction may underlie many of the cardinal symptoms associated with ADHD. We tested the following hypotheses: (1) adult subjects meeting DSM-IV criteria for ADHD, predominantly hyperactive-impulsive type, would display neuropsychological deficits on tasks sensitive to orbitofrontal dysfunction; (2) adult subjects meeting DSM-IV criteria for ADHD, predominantly inattentive type, would perform poorly on measures sensitive to DLPF dysfunction; and (3) adult subjects meeting DSM-IV criteria for ADHD, combined type, would exhibit performance deficits on orbitofrontal measures and on DLPF tasks. Results partially confirmed our hypotheses. Subtyping ADHD patients revealed important group differences. Distinct neurocognitive and clinical profiles were observed.     

WAIS digit span-based indicators of malingered neurocognitive dysfunction: classification accuracy in traumatic brain injury

The present study determined specificity and sensitivity to malingered neurocognitive dysfunction (MND) in traumatic brain injury (TBI) for several Wechsler Adult Intelligence Scale (WAIS) Digit Span scores. TBI patients (n = 344) were categorized into one of five groups: no incentive, incentive only, suspect, probable MND, and definite MND. Performance of 1,063 nonincentive patients (e.g., cerebrovascular accident, memory disorder) was also examined. Digit Span scores included reliable digit span, maximum span forward both trials correct, maximum span forward, combined maximum forward and backward span, Digit Span scaled score, maximum span backward both trials correct, and maximum span backward. In TBI, sensitivity to MND ranged from 15% to greater than 30% at specificities of 92% to 98%. Patient groups with documented brain pathology had higher false-positive error rates. These results replicate previous known-groups malingering studies and provide valuable data supporting the WAIS Digit Span scores in detection and diagnosis of malingering.     

Discrepancies between standardized measures of cognitive level and Halstead-Reitan impairment indices as inferences of brain damage following head injuries

z scores for measures of intelligence, memory, educational achievement, and neuropsychological impairment were obtained for 193 patients who had sustained impacts of mechanical energy to their skulls. Two sets of normative data, adjusted for age and sex and not adjusted for these variables, were employed to compute indices of neurocognitive proficiency (the inverse of impairment). 80% or 76 of the 96 patients whose Halstead-Reitan Indices were greater than 0.4 displayed scores for neurocognitive proficiency that were two or more standard deviations below the averages of their scores for intelligence, memory, and educational achievement. None of the patents whose Impairment Indices were 0.4 or less displayed this discrepancy. There were no statistically significant differences between these two groups of patients with respect to the presence of unconsciousness following the injury or the duration of posttraumatic memory disruptions. The results indicate that quantitative scores for neuropsychological impairments are still the most accurate criteria to discern brain dysfunction within the mild to moderate range.     

California verbal learning test indicators of Malingered Neurocognitive Dysfunction: sensitivity and specificity in traumatic brain injury

The present study used well-defined traumatic brain injury (TBI) and mixed neurological (other than TBI) and psychiatric samples to examine the specificity and sensitivity to Malingered Neurocognitive Dysfunction (MND) of four individual California Verbal Learning Test (CVLT) variables and eight composite CVLT malingering indicators. Participants were 275 traumatic brain injury and 352 general clinical patients seen for neuropsychological evaluation. The TBI patients were assigned to one of five groups using the Slick, Sherman, and Iverson (1999) criteria: no incentive, incentive only, suspect, and malingering (both Probable MND and Definite MND). Within TBI, persons with the strongest evidence for malingering (Probable and Definite) had the most extreme scores. Good sensitivity (approximately 50%) in the context of excellent specificity (> 95%) was found in the TBI samples. Issues related to the appropriate clinical application of these data are discussed.     

Neurocognitive impairment does not predict treatment outcome in obsessive-compulsive disorder

There is conflicting evidence pertaining to whether or not neurocognitive task performance at baseline predicts treatment response in obsessive-compulsive disorder (OCD). In the present study, we administered a set of executive neurocognitive tests with a putative sensitivity for treatment outcome to a sample of 138 OCD patients. Additionally, subjective neurocognitive dysfunction was determined via a questionnaire. All patients participated in a cognitive-behavioural treatment program (CBT). Results showed that responders (n = 73) did not differ from non-responders (n = 65) on any of the parameters except for decreased performance on the delayed alternation test (p < .1, effect size: .61). A subsidiary analysis revealed that slowing on the Trail-Making Test A and an enhanced rate of perserveration errors on the Wisconsin Card Sorting Test predicted poor outcome for the treatment of compulsions. It is concluded that neurocognitive impairment does not represent a reliable early warning sign for non-response to CBT.     

Utility of the trauma symptom inventory's atypical response scale in detecting malingered post-traumatic stress disorder

The authors examined the Trauma Symptom Inventory's (TSI) ability to discriminate 88 student post-traumatic stress disorder (PTSD) simulators screened for genuine PTSD from 48 clinical PTSD-diagnosed outpatients. Results demonstrated between-group differences on several TSI clinical scales and the Atypical Response (ATR) validity scale. Discriminant function analysis using ATR revealed 75% correct patient classification but only 48% correct simulator classification, with an overall correct classification rate of 59% (positive predictive power [PPP] = .71; negative predictive power [NPP] = .51). Individual ATR cutoff scores did not yield impressive classification results, with the optimal cutoff (T score = 61) correctly classifying only 61% of simulators and patients (PPP = .66, NPP = .54). Although ATR was not developed as a malingered PTSD screen, instead serving as a general validity screen, caution is recommended in its current clinical use for detecting malingered PTSD.     

Hormones and Cognition: Current Concepts and Issues in Neuropsychology

This article provides an extensive and comprehensive review of the effects of hormones on cognition. Studies detailing specific neurocognitive functions affected by variation in hormone levels across the life span are presented. Dysregulation of hormone levels is considered from models of both normal and diseased functioning. Patterns of cognitive dysfunction are described for a range of syndromes involving the neuroendocrine system, and evidence of specific neurophysiological mechanisms that can account for these findings is outlined. This review includes discussion of treatment outcomes and the permanency of endocrine-related cognitive dysfunction. The authors present a set of guidelines for clinical neuropsychologists to use for assessment of patients with neuroendocrine system dysfunction. Clinical and methodological issues in research and treatment settings are discussed.     

Subtyping obsessive-compulsive disorder: neuropsychological correlates

We administered neuropsychological measures considered sensitive to prefrontal dysfunction (both orbitofrontal and dorsolateral prefrontal neocortex) to obsessive-compulsive disorder (OCD) patients and control subjects. OCD subjects exhibited performance deficits, in comparison to community controls, on three measures sensitive to orbitofrontal neocortex dysfunction. Contrary to expectation, OCD patients also exhibited performance deficits on measures sensitive to dorsolateral prefrontal neocortex dysfunction. However, distinct neurocognitive profiles emerged when we examined the impact of comorbid schizotypal personality features on neuropsychological test performance. Primary OCD patients displayed impaired performance on measures sensitive to orbitofrontal dysfunction; however, they did not differ from control subjects on tests of dorsolateral function. OCD subjects presenting with schizotypal personality features performed poorly not only on tests sensitive to orbitofrontal dysfunction, but also on tests sensitive to dorsolateral dysfunction. Findings suggest that OCD can be subdivided into clinical subtypes, and distinct prefrontal subsystems may be differentially involved in these subtypes.     

Computerized Neurocognitive Testing in the Management of Sport-Related Concussion: An Update

Since the late nineties, computerized neurocognitive testing has become a central component of sport-related concussion (SRC) management at all levels of sport. In 2005, a review of the available evidence on the psychometric properties of four computerized neuropsychological test batteries concluded that the tests did not possess the necessary criteria to warrant clinical application. Since the publication of that review, several more computerized neurocognitive tests have entered the market place. The purpose of this review is to summarize the body of published studies on psychometric properties and clinical utility of computerized neurocognitive tests available for use in the assessment of SRC. A review of the literature from 2005 to 2013 was conducted to gather evidence of test-retest reliability and clinical validity of these instruments. Reviewed articles included both prospective and retrospective studies of primarily sport-based adult and pediatric samples. Summaries are provided regarding the available evidence of reliability and validity for the most commonly used computerized neurocognitive tests in sports settings.     

Development of a Brief Cognitive Screen for Mild Cognitive Impairment and Neurocognitive Disorder

Abstract

The purpose of this study was to develop and evaluate a brief cognitive screen for possible Mild Cognitive Impairment (MCI) and other neurocognitive impairment in a sample of general medical patients. Two hundred community-dwelling general medical patients aged 65 or older participated in this study. Age and education corrected scores from the Rey Auditory Verbal Learning Test and Mattis Dementia Rating Scale were used to classify participants into three groups: MCI, neurocognitive disorder, cognitively intact. Groups were then compared on an independent set of measures: the Consortium to Establish a Registry for Alzheimer’s Disease (CERAD) neuropsychological battery, Mini-Mental State Examination, and Clock Drawing Test. The MCI group constituted 9% of the sample, while 10.5% of the sample was classified into the neurocognitive disorder group. The CERAD Verbal Category Fluency and CERAD Word List Memory Test Delayed Recall measures were individually and collectively the most effective in differentiating cognitively intact elders from persons in both the MCI and neurocognitive disorder groups. We conclude that these two brief measures appear to be effective for detecting possible MCI or neurocognitive disorder, thereby facilitating identification of candidates who would benefit from more detailed neuropsychological assessment.     

Neurological malingering

The detection of malingering in terms of neurologic signs and symptoms is described, including malingered coma, simulated deafness, feigned blindness, feigned weakness, and diminished sensation. While neurologic malingering is not an actual diagnosis, it is best detected through medical procedures. To identify malingering, the physician must demonstrate that the malingered sign or symptom is not caused by a diagnosable order and is instead clearly a consequence of the subject's volition.     

Neuropsychological profile in patients with schizotypal personality disorder or schizophrenia

Neuropsychological impairments have been consistently reported in patients with schizophrenia. As little is known whether subjects with schizotypal personality disorder exhibit neurocognitive dysfunction similar to that in schizophrenia, we assessed the neuropsychological profile of 15 subjects with schizotypal personality disorder and compared it with that for 15 patients with schizophrenia and for 15 psychiatrically normal volunteers. All participants were administered a standard neuropsychological battery assessing language ability, spatial ability, visuomotor function, verbal memory, visual memory, auditory attention, visual attention, and executive function. Performance on most of the cognitive domains was impaired in patients with schizotypal personality disorder but less than patients with schizophrenia. Specifically, impairment in verbal memory and visuomotor ability in patients with schizotypal personality disorder and patients with schizophrenia were comparable, while patients with schizophrenia performed worse on the test of executive function than did patients with schizotypal personality disorder. As a whole, cognitive deficits in patients with schizotypal personality disorder were qualitatively similar to, but quantitatively milder than, those for patients with schizophrenia. The results suggest that cognitive abilities related to frontotemporal lobe function are disturbed across these schizophrenia-spectrum disorders.     

Feigning in adjudicative competence evaluations

Competence to stand trial (adjudicative competence) is the most requested forensic psychiatric evaluation, with an estimated 60,000 referrals annually. The challenge of detecting feigned incompetence has not been systematically studied until the past decade. Estimates of feigned adjudicative incompetence vary from 8 to 21%. This article reviews techniques for detecting malingered psychosis and malingered cognitive impairment during competence evaluations. Specific techniques for assessing feigned adjudicative incompetence and estimating the malingerer's genuine abilities are discussed. A stepwise approach to suspected feigned adjudicative incompetence is proffered. Copyright © 2010 John Wiley & Sons, Ltd.     

Obstructive Sleep Apnea Syndrome in Prader-Willi Syndrome: An Unrecognized and Untreated Cause of Cognitive and Behavioral Deficits?

Prader-Willi Syndrome (PWS) is a rare genetic disorder characterized by a range of physical, psychological, and physiological abnormalities. It is also distinguished by the high prevalence of obstructive sleep apnea syndrome (OSAS), i.e., repetitive upper airway collapse during sleep resulting in hypoxia and sleep fragmentation. In non-PWS populations, OSAS is associated with a range of neurocognitive and psychosocial deficits. Importantly, these deficits are at least partly reversible following treatment. Given the findings in non-PWS populations, it is possible that OSAS may contribute to neurocognitive and psychosocial deficits in PWS. The present review examines this possibility. While acknowledging a primary contribution from the primary genetic abnormality to central neural dysfunction in PWS, we conclude that OSAS may be an important secondary contributing factor to reduced neurocognitive and psychosocial performance. Treatment of OSAS may have potential benefits in improving neurocognitive performance and behavior in PWS, but this awaits confirmatory investigation.     

Effect of symptom information and intelligence in dissimulation: an examination of faking response styles by inmates on the Basic Personality Inventory

This study employed the Basic Personality Inventory (BPI) to differentiate various types of dis-simulation, including malingered psychopathology and faking good, by inmates. In particular, the role of intelligence in utilizing symptom information to successfully malinger was examined. On admission to a correctional facility, 161 inmates completed the BPI under standard instructions and then again under instructions to fake good (n = 55) or to malinger psychotic (n = 35), posttraumatic stress disorder (n = 36), or somatoform (n = 35) psychopathology. Unlike symptom information, intelligence evidenced some support for increasing inmates' effectiveness in malingering, although there was no relationship between higher intelligence and using symptom information to successfully evade detection. Overall, the BPI was more effective in detecting malingered psychopathology than faking good. Implications for the detection of dissimulation in correctional and forensic settings are discussed.     

An analysis of neurological soft signs in children with learning problems

Eighty children with learning problems were systematically evaluated for neurological soft signs, general intelligence, scholastic achievement, hyperactivity, and neurocognitive dysfunction. A factor analysis yielded six factors, and a higher order, general ability factor was derived from an orthogonal rotation. Neurocognitive functions appeared in three factors suggesting “types” of dysfunctions. The higher order general ability factor represents a broad range of skills. The two other factors with neurocognitive loads suggest a distinction between verbal-motor integration and visual-motor integration. Age, sex, and hyperactivity formed the remaining clusters.     

An introduction to organic brain syndromes

Organic brain syndromes are of forensic interest for several reasons. First, patients with organic brain syndromes may require judicial determination of competence in any of a number of areas, e.g., testamentary capacity, need for financial guardianship, or competence to make medical decisions. Second, any patient whose mental state is of legal interest will need evaluation for contributing organic factors; uncovering these factors may have considerable medical and legal consequence. Third, the discovery of organic factors may be decisive in the outcome of a judicial proceeding, where “hard” biological data are often accorded more weight, and are thus more persuasive, than “soft” psychological data. This article provides an introductory overview of the organic brain syndromes. For each syndrome, the clinical features are described and are illustrated with a case vignette, the more common etiologies are presented, and selected aspects to the evaluation are highlighted. In addition, since the detectian of malingered mental illness is a key component in many forensic contexts, characteristics are described which help to distinguish actual from malingered mental illness.