Visuospatial and Attentional Abilities Predict Driving Simulator Performance Among Older HIV-infected Adults.

OBJECTIVES: To examine the effects of aging and neuropsychological (NP) impairment on driving simulator performance within a human immunodeficiency virus (HIV)-infected cohort. METHODS: Participants included 79 HIV-infected adults (n = 58 > age 50, n = 21 ≤ 40) who completed a NP battery and a personnel computer-based driving simulator task. Outcome variables included total completion time (time) and number of city blocks to complete the task (blocks). RESULTS: Compared to the younger group, the older group was less efficient in their route finding (blocks over optimum: 25.9 [20.1] vs 14.4 [16.9]; P = .02) and took longer to complete the task (time: 1297.6 [577.6] vs 804.4 [458.5] seconds; P = .001). Regression models within the older adult group indicated that visuospatial abilities (blocks: b = -0.40, P <.001; time: b = -0.40, P = .001) and attention (blocks: b = -0.49, P = .001; time: b = -0.42, P = .006) independently predicted simulator performance. The NP-impaired group performed more poorly on both time and blocks, compared to the NP normal group. CONCLUSIONS: Older HIV-infected adults may be at risk of driving-related functional compromise secondary to HIV-associated neurocognitive decline.

Operationalization of the updated diagnostic algorithm for classifying HIV-related cognitive impairment and dementia.

BACKGROUND: This study applies the updated HIV-Associated Neurocognitive Disorders (HAND) diagnostic algorithm. METHODS: Participants were 210 HIV-infected-adults, classified using proposed HAND criteria: HIV-Associated Dementia (HAD), Mild Neurocognitive Disorder (MND), Asymptomatic Neurocognitive Impairment (ANI). RESULTS: The algorithm yielded: normal = 32.8%, ANI = 21.4%, MND = 34.3%, and HAD = 11.4%. Normal participants performed superior to HAND-defined participants on cognition, and HAD participants performed more poorly on global cognition and executive functioning. Two distinct subgroups of interest emerged: (1) functional decline without cognitive impairment; (2) severe cognitive impairment and minimal functional compromise. CONCLUSIONS: The algorithm discriminates between HIV-infected cognitively impaired individuals. Diagnosis yields two unique profiles requiring further investigation. Findings largely support the algorithm's utility for diagnosing HIV-cognitive-impairment, but suggest distinct subsets of individuals with discrepant cognitive/functional performances that may not be readily apparent by conventional application of HAND diagnosis.

DHEAS and POMS measures identify cocaine dependence treatment outcome.

UNLABELLED: Early attrition is a significant problem in the treatment of cocaine dependence, but it is unclear why some patients succeed in treatment while others relapse or drop out of treatment without a demonstrated relapse. The goal of this study was to determine whether baseline levels of select hormones, including the adrenal hormone and excitatory neurosteroid dehydroepiandrosterone sulfate (DHEAS), would distinguish between treatment outcome groups. Based on the literature, completion of 90 days of treatment was established as a key outcome variable. METHODS: Quantitative urine levels of the cocaine metabolite benzoylecgonine (BE) and other substance of abuse analytes, plasma levels of DHEAS, DHEA, cortisol, and prolactin, and the profile of mood states (POMS) were serially measured in 38 male cocaine-dependent (DSM-IV) patients and in 28 controls of similar gender and age over a six month study. Exclusion criteria for the patients and controls included Axis I mood, anxiety or psychotic disorders. The patients could not manifest substance dependence except to cocaine. The patients and controls received remuneration for urine and blood collection. Blood samples for hormone levels were obtained between 8 and 10 a.m. on days 1, 14 and 21 of a 21-day inpatient treatment program and throughout 6 months of outpatient study visits at 45-day intervals. RESULTS: Attrition from treatment and study appointments occurred predominately at the junction between inpatient and outpatient programs. Forty percent of patients made the transition to outpatient treatment and remained abstinent and in treatment for a median of 103 days (ABST). Forty-two percent of patients dropped out of treatment during the inpatient stay or never returned after completing the inpatient program (DO) and 18% had a documented relapse either during, or within the first week after, the inpatient stay (REL). POMS total scores were elevated at treatment entry for both the ABST and DO groups. Plasma DHEAS levels in the DO patients were decreased compared to controls and increased in the ABST patients. POMS total scores for the REL patients at baseline were at control levels. Baseline cortisol levels were not statistically different between the outcome groups, though they were elevated for all cocaine patient groups. When treatment outcome was collapsed into whether patients completed (ABST) or did not complete 90 days of treatment (90N), ABST plasma DHEAS and cortisol were significantly elevated compared to the 90N patients and controls across the first 3 weeks of cocaine withdrawal. CONCLUSIONS: At treatment entry, each of the three patient outcome groups was identified by levels of circulating DHEAS and distressed mood. In the ABST patients, distressed mood during withdrawal may have been mitigated through antidepressant-like actions of enhanced endogenous DHEAS activity, thus contributing to improved abstinence and treatment retention. Patients, such as the DO group, with high levels of distressed mood at treatment entry and low DHEAS levels may benefit from adjunctive pharmacotherapy that targets DHEAS and POMS measures. Patients, such as the REL group, who lack distressed mood at treatment entry, may require intense application of motivational approaches plus residential treatment.

Neurocognitive functioning is associated with employment status: a quantitative review.

Neurocognitive assessment is frequently used as a basis for making determinations regarding a person's ability to work; yet, to our knowledge, a review of the association between neurocognition and employment status has not been conducted. For this review, we utilized meta-analysis to quantify objectively the association between eight neurocognitive domains and employment status. The meta-analysis revealed that performance in each domain was significantly associated with employment status, and that the associations were greatest for the following domains: intellectual functioning, executive functioning, and memory. These findings support the ecological validity of neurocognitive assessment.

Base rate of a WMS-R malingering index in a sample of non-compensation-seeking men infected with HIV-1.

HIV-1 infected persons who are pursuing disability benefits are increasingly seeking neuropsychological assessment for purposes of corroborating functional impairment. Thus, research on the utility of measures of symptom validity among these patients is needed. Recently, Mittenberg, Azrin, Millsaps, and Heilbronner (1993) proposed a malingering index score for the WechslerMemoryScale-Revised that is derived by subtracting the Attention/Concentration Index (ACI) score from the General Memory Index Score (GMI). This study is a cross-validation of the specificity of the GMI-ACI Malingering Index in a sample of 55 non-compensation-seeking HIV-positive (HIV+) patients. An overall false-positive rate of 7% was observed for the GMI-ACI Malingering Index. However, further analyses showed that GMI-ACI Malingering Index scores were correlated with GMI scores such that false-positive errors were substantially higher (18%) among patients who obtained above-average GMI scores. These findings suggest a cautious approach to application of the GMI-ACI Malingering Index, particularly among patients who obtain above-average GMI scores.

Effects of acute smoked marijuana on complex cognitive performance.

Although the ability to perform complex cognitive operations is assumed to be impaired following acute marijuana smoking, complex cognitive performance after acute marijuana use has not been adequately assessed under experimental conditions. In the present study, we used a within-participant double-blind design to evaluate the effects acute marijuana smoking on complex cognitive performance in experienced marijuana smokers. Eighteen healthy research volunteers (8 females, 10 males), averaging 24 marijuana cigarettes per week, completed this three-session outpatient study; sessions were separated by at least 72-hrs. During sessions, participants completed baseline computerized cognitive tasks, smoked a single marijuana cigarette (0%, 1.8%, or 3.9% Delta(9)-THC w/w), and completed additional cognitive tasks. Blood pressure, heart rate, and subjective effects were also assessed throughout sessions. Marijuana cigarettes were administered in a double-blind fashion and the sequence of Delta(9)-THC concentration order was balanced across participants. Although marijuana significantly increased the number of premature responses and the time participants required to complete several tasks, it had no effect on accuracy on measures of cognitive flexibility, mental calculation, and reasoning. Additionally, heart rate and several subjective-effect ratings (e.g., "Good Drug Effect," "High," "Mellow") were significantly increased in a Delta(9)-THC concentration-dependent manner. These data demonstrate that acute marijuana smoking produced minimal effects on complex cognitive task performance in experienced marijuana users.

Hippocampal and anterior cingulate activation deficits in patients with geriatric depression.

OBJECTIVE: The authors assessed frontotemporal function in patients with geriatric depression, a debilitating and increasingly prevalent disorder that has not been examined with brain activation paradigms. METHOD: Six depressed elderly patients and five healthy comparison subjects underwent high-sensitivity [(15)O]H(2)O positron emission tomography scans during a paced word generation task and a resting condition. RESULTS: Bilateral activation deficits were noted in the dorsal anterior cingulate gyrus and hippocampus of the depressed geriatric patients relative to the comparison subjects. Patients had memory deficits that correlated with lower hippocampal activity during both rest and activation. CONCLUSIONS: These initial findings suggest that hippocampal and dorsal anterior cingulate hypoactivation may constitute contributing neural substrates of geriatric depression. They also suggest that hippocampal dysfunction is related to the memory dysfunction characteristic of this disorder.

Post-Daubert admissibility of scientific evidence on malingering of cognitive deficits.

In Daubert v. Merrell Dow Pharmaceuticals, Inc. (1993) the Supreme Court held that evidence must be "reliable" to be admissible and for scientific evidence "evidentiary reliability" is based on scientific validity. This article addresses the question "Do the Rey 15-Item Test ('FIT'), the Test of Memory Malingering ('TOMM'), and the Validity Indicator Profile ('VIP') likely meet the Daubert standard for admissibility of scientific evidence?" Sensitivity, specificity, positive and negative predictive values (PPV and NPV, respectively), and base rates of 30 and 15 percent were calculated for each test. Given the existing literature on malingering and the implications of a misclassification of malingering, we discuss the findings for each of the three tests using a PPV > or = 80 percent with a base rate of malingering of < or = 30. Our analyses indicate that the Rey 15-FIT fails to meet this standard of scientific validity. In contrast, the TOMM shows high specificity and PPV, and our findings suggest cautious optimism regarding the VIP. These results are discussed within the context of the courts' guidelines for the Daubert standard.

Long-term effects of high-dose zidovudine treatment on neuropsychological performance in mildly symptomatic HIV-positive patients: results of a randomized, double-blind, placebo-controlled investigation.

This study examined the treatment outcome of high-dose (1500 mg/day) zidovudine (AZT) on neuropsychological (NP) functioning (Trailmaking Test A & B, WAIS-R Digit Symbol, and Rey Auditory Verbal Learning Test) across a 12-month period in mildly symptomatic HIV-1 seropositive men (n = 46 at entry) enrolled in a randomized, double-blind, placebo-controlled trial (VA Cooperative Studies Program #298). Neither short-term (0-6 months) nor long-term (0-12 months) AZT administration revealed enhancement in NP performance. The results suggest that, although AZT may afford patients prophylactic benefits, protracted high-dose AZT treatment does not improve NP functioning in mildly symptomatic HIV-positive individuals.

Diffusion tensor imaging of patients with HIV and normal-appearing white matter on MR images of the brain.

BACKGROUND AND PURPOSE: HIV enters the CNS early in the course of infection and produces neuropsychiatric impairment throughout the course of illness, which preferentially affects the subcortical white matter. The development of a neuroimaging marker of HIV may allow for the earliest detection of cognitive impairment. The purpose of this study was to determine whether MR diffusion tensor imaging can detect white matter abnormalities in patients who have tested positive for HIV. METHODS: Ten patients with HIV (eight men and two women; mean age, 42 years) underwent MR imaging of the brain with MR diffusion tensor imaging, which included routine fluid-attenuated inversion recovery and fast spin-echo T2-weighted imaging. Diffusion constants and anisotropy indices were calculated from diffusion tensor maps. Peripheral viral load, Centers for Disease Control staging, and cluster of differentiation 4 levels were determined. RESULTS: All patients had normal results of MR imaging of the brain, except for mild atrophy. Four of 10 patients had undetectable viral loads. These patients were receiving highly active antiretroviral therapy. The diffusion constant and anisotropy were normal. Four of 10 patients had viral loads between 10,000 and 200,000. Diffusion anisotropy in the splenium and genu was significantly decreased (P < .02). The diffusion constant of the subcortical white matter was elevated in the frontal and parietooccipital lobes (11%). Two of 10 patients had viral loads >400,000. Anisotropy of the splenium was half normal (P < .0004) and of the genu was decreased 25% (P < .002). The average diffusion constant was diffusely elevated in the subcortical white matter. CONCLUSION: Calculating the diffusion constant and anisotropy in the subcortical white matter and corpus callosum in patients with HIV detected abnormalities despite normal-appearing white matter on MR images and nonfocal neurologic examinations. Patients with the highest diffusion constant elevations and largest anisotropy decreases had the most advanced HIV disease. Patients with the lowest viral load levels, who had normal anisotropy and diffusion constants, were receiving highly active antiretroviral therapy.

Relationships among apathy, depression, and cognitive impairment in HIV/AIDS.

This study was designed to determine whether apathy is associated with neurocognitive symptoms and/or depressive symptoms in HIV/AIDS and also whether apathy is associated with patient expectancies about antiretroviral medication adherence. Seventy-five HIV+ homosexual men and 58 HIV+ women were assessed for depressive disorders and symptoms. Neuropsychological tests measured attention, concentration, learning, memory, executive function, and psychomotor speed. Other measures included Marin's Apathy Evaluation Scale, the Adherence Determinants Questionnaire, CD4 cell count, and HIV RNA viral load. Apathy was consistently related to depression and unrelated to neuropsychological impairment. Patient expectancies regarding medication adherence were unrelated to apathy when the analysis was controlled for depressive symptoms.

Psychiatric comorbidity of methamphetamine dependence in a forensic sample.

The objective of this study was to examine the association between psychiatric symptoms and methamphetamine dependence. A four-hour survey was administered to 1,580 arrestees sampled from the 14 most populous counties in California. The survey included items assessing demographic profile, history of substance dependence, and psychiatric symptomatology. In the 12 months prior to the assessment, methamphetamine-dependent individuals were more likely to report depressive symptoms and suicidal ideation than individuals denying methamphetamine dependence, even after controlling for demographic profile and dependence on other drugs. Methamphetamine-dependent individuals also were more likely to report a need for psychiatric assistance at the time of the interview. These findings suggest that methamphetamine-dependent individuals are at greater risk to experience particular psychiatric symptoms. Further study to determine the etiology of these symptoms is warranted.

Subtypes of cognitive impairment in depressed older adults.

The authors examined the cognitive profiles of 104 older adults with major depression and empirically identified three subgroups with distinct patterns of cognitive impairment. The entire sample demonstrated memory impairment relative to age-standardized scores, distributed equally across the three cognitive subgroups. One-third of subjects displayed either executive impairment or attentional deficits. The subgroup with executive dysfunction had greater behavioral disability. Identification of executive impairment in depressed older adults may facilitate intervention for disturbances in planning, sequencing, organizing, and abstracting. Demonstrating the presence of subtypes of cognitive impairments in older adults may provide the basis for further investigation of mechanisms of late-life depression and the pathophysiology of antidepressant response. The association of behavioral disability with executive dysfunction can initiate an inquiry into the biology of functional impairment ultimately linking biological research to studies of treatment effectiveness.

A dramatic loss of non-verbal intelligence following a right parietal ependymoma: brief case report.

Virtually all reports on the effects of focal brain lesions upon specific neuropsychological functions are based upon estimates of cognitive loss in persons following a lesion, without proof of premorbid capacity. This report presents the case of a 19-year-old left-handed male with assessment of Verbal and Performance I.Q. testing 1 year prior to a subsequent brain tumor for reasons unrelated to the neoplasm. The patient was then re-tested 23 months later, following the diagnosis and treatment of a supratentorial ependymoma in the right parietal region. His multi-modal treatment regimen included a partial surgical resection of the tumor, cranio-spinal irradiation with focal boost to the primary site, and chemotherapy. Results demonstrate a striking 58-point decline in the Wechsler Adult Intelligence Scale - Revised (WAIS - R) Performance I. Q. with no significant change in Verbal I.Q. These findings clearly document the important cognitive functions associated with the right parietal lobe.

Responses to perceived unethical practices in clinical neuropsychology: ethical and legal considerations.

Neuropsychologists often review the work of colleagues who have performed a neuropsychological evaluation. At times, these reviews may cause one to believe that a colleague acted in an unethical manner. However, it is often unclear whether the situation warrants contacting the colleague or filing a complaint. This article provides examples of potential unethical practices in neuropsychology, and then reviews the relevant ethical principles and legal precedents concerning the obligations and possible risks of reporting perceived unethical practices of a colleague. The paper concludes with a series of recommendations and options as to when and how one should proceed in such situations.

The future of criminal violence: juveniles tried as adults.

Juveniles tried as adults (JTA) represent a select and small subsample of juvenile offenders. This study seeks to provide a profile of habitually violent JTAs transferred to the adult penal system and to compare them with their adult counterparts. Twenty-nine incarcerated violent male juveniles tried as adults were compared with a sample of 27 incarcerated violent male offenders across demographic, neuropsychological, criminal history, psychopathy, and substance abuse variables. The JTAs were characterized by a high rate of gang membership (96%), substance abuse (alcohol, marijuana, and phenylcyclidene), and use of guns. In the juvenile sample, 65 percent used guns in violence not leading to arrest, and 93 percent used guns in a violent crime leading to arrest. Juvenile offenders were similar to their adult counterparts in patterns of criminality, although adult offenders had higher psychopathy scores. Both groups revealed generally intact neuropsychological functioning with the exception of a higher rate of perseverative responses in the adult sample. The results are discussed in terms of the implication of the degree of violence in a young offender population.

Have we forgotten the base rate problem? Methodological issues in the detection of distortion.

The search for valid and reliable methods of detecting malingering and distortion has become an increasingly important task for forensic psychologists and neuropsychologists. This report highlights several important methodological issues commonly observed in research on the prediction of malingering. The choice of indices for determining optimal cutoff scores on the utility of existing measures, the impact of base rates of malingering on the accuracy of prediction models, the incremental accuracy of combining multiple measures, and the relationship of test validity to the interpretation of data are described with regard to the prediction of malingering on neuropsychological tests. These methodological concerns are discussed in reference to several recent publications assessing the utility of various methods for the detection of malingering.

The relationship between employment and neuropsychological impairment in HIV infection.

The relationship between neurocognitive impairment and employment in a cohort of 130 predominantly symptomatic individuals with HIV-1 infection was examined. Participants were classified as employed (full or part-time for pay) or unemployed (N = 64) and administered a neuropsychological test battery. When covarying for CD4 count, age, and physical limitations, the results revealed that unemployed men performed below that of employed participants on tasks of memory, set shifting-cognitive flexibility, and psychomotor speed. The results are discussed within the context of similar findings in other illnesses.

Declarative and procedural memory in bipolar disorder.

BACKGROUND: Memory function is an important but under researched area for neuropsychological investigation in persons with bipolar disorder. Previous studies have reported cognitive deficits on tasks of declarative memory in bipolar patients in the euthymic state. METHODS: This study extended these findings by investigating declarative as well as procedural learning and memory in bipolar patients (with and without alcohol abuse) who were examined in the euthymic state. The California Verbal Learning Test, Star Mirror Tracing Task, Pursuit Rotor Task, American National Adult Reading Test, and the Vocabulary Subtest of the WAIS-R, were administered to bipolar patients and control subjects by researchers who were blind to the subject's group. RESULTS: Bipolar patients performed worse than control subjects on a measure of declarative memory (California Verbal Learning Test) but did not differ from the performance of control subjects on either of the two procedural learning tasks (Pursuit Rotor Task and Star Mirror Task). CONCLUSIONS: These results suggest disturbed function of temporal lobe, but not basal ganglia, structures in persons with bipolar disorder.

Screening for dementia: comparison of three commonly used instruments.

The sensitivity and specificity of three cognitive screening measures - the Mini-Mental State Exam (MMSE), Mattis Dementia Rating Scale (MDRS), and Neurobehavioral Cognitive Status Examination (NCSE) - were compared in a cohort of subjects with dementia as well as normal elderly individuals. Twenty-two patients met criteria for probable Alzheimer' s disease (AD), 19 for vascular dementia (VaD), and 12 were normal control subjects. The use of standard cutpoints resulted in poor to good classification accuracy for the three measures, but measurable improvement in sensitivity was obtained by adjusting the cutpoints for each measure. Discriminatory power was maximized with an MMSE cutpoint of < or = 26, an MDRS cutpoint of < or = 134, and requiring one or more NCSE subtests to be in the impaired range. Use of age and education adjusted norms resulted in good to excellent classification accuracy for the MMSE and MDRS. The NCSE subtest score pattern failed to differentiate between AD and VaD.