The Effect of Donepezil on Problem-solving Ability in Individuals With Amnestic Mild Cognitive Impairment: A Pilot Study

BACKGROUND

Clinical trials involving individuals with mild cognitive impairment (MCI) have reported mixed results for the effects of cholinesterase inhibitors on cognitive outcomes. Our previous work demonstrated that a visuospatial problem-solving task was sensitive to non-memory impairments in individuals with MCI.

OBJECTIVE

To determine whether the same task is also sensitive to the effects of cholinesterase inhibitors in individuals with amnestic MCI (aMCI).

METHOD

We gave 22 individuals with aMCI (clinical dementia rating of 0.5) and Mini-Mental State Examination (MMSE) scores of at least 24 the following measures at baseline and at follow-up 1 year later: Hopkins Verbal Learning Test, Boston Naming Test, Rey Complex Figures Test copying task, anagrams task, and visuospatial problem-solving task. The MMSE was also given at the 1-year follow-up. Twelve of the individuals were drug naïve, having never taken cholinesterase inhibitors before, and donepezil was initiated and titrated to 10 mg daily after baseline in an open-label manner. Ten of the individuals had already been taking donepezil, and there was no change in treatment. We compared the two groups for amount of performance change over 1 year.

RESULTS

Individuals for whom donepezil was initiated performed significantly better on the visuospatial problem-solving task after 1 year compared with individuals who had already been taking donepezil. No difference was observed for any of the other variables.

CONCLUSION

The visuospatial problem-solving task appeared to be more sensitive than memory measures to the effects of cholinesterase inhibitors in individuals with aMCI, perhaps due to the high attentional demand of the task.

Validity of the Verbal Concept Attainment Test in multiple sclerosis

OBJECTIVE

As many as 70% of people with multiple sclerosis (MS) have clinically significant cognitive impairment, and most of these individuals exhibit executive dysfunction. Most research concerning executive dysfunction in MS has focused upon nonverbal measures. The Verbal Concept Attainment Test (VCAT) has demonstrated construct validity as an executive function measure in people infected with HIV and in people with focal brain lesions, but its validity among people with MS is unknown. The current study evaluated the VCAT's criterion, diagnostic, and ecological validity in people with MS.

METHOD

A comprehensive neuropsychological battery was administered to 44 healthy individuals and 97 people with MS. Based on existing norms, they were classified as impaired or unimpaired, resulting in 65 people with MS categorized as unimpaired and 32 as impaired. They were administered a battery assessing neuropsychological impairment and disability status.

RESULTS

The VCAT correlated with most measures of neuropsychological function, but its largest correlations occurred with measures of executive function, working memory, and verbal memory. Regarding classification accuracy, the VCAT achieved satisfactory sensitivity and specificity in identifying neuropsychological impairment in people with MS. The VCAT achieved moderate correlations with measures of disability status.

CONCLUSIONS

The data provide evidence for an optimal VCAT cutoff score for establishing neuropsychological impairment in people with MS, and they demonstrate that the VCAT possesses acceptable criterion, diagnostic, and ecological validity. As such, these data support the inclusion of the VCAT in research and clinical practice involving people with MS.

Digitally translated Self-Administered Gerocognitive Examination (eSAGE): relationship with its validated paper version, neuropsychological evaluations, and clinical assessments

Background

The original paper Self-Administered Gerocognitive Examination (SAGE) is a valid and reliable cognitive assessment tool used to identify individuals with mild cognitive impairment (MCI) or early dementia. We evaluated identical test questions in a digital format (eSAGE) made for tablet use with the goals of calibrating it against SAGE and establishing its association with other neuropsychological tests and clinical assessments of cognitive impairment.

Methods

Subjects aged 50 and over who had taken SAGE were recruited from community and clinic settings. Subjects were randomly selected to participate in a clinical evaluation including neuropsychological evaluations. SAGE and eSAGE were administered using a crossover design. Subjects were identified as dementia, MCI, or normal based on standard clinical criteria. Associations were investigated using Spearman correlations, linear regression, and sensitivity and specificity measures.

Results

Of the 426 subjects screened, 66 completed the evaluation. eSAGE score correlation to a battery of neuropsychological tests was 0.73 (p < 0.0001) with no significant difference between the paper and digital format. Spearman correlation of SAGE versus eSAGE was 0.88 (p < 0.0001), and they are related by the formula: eSAGE score = –1.05 + 0.99 × SAGE score. Since the slope is very close to 1 (p = 0.86) there is strong evidence that the scaling is identical between eSAGE and SAGE, with no scale bias. Overall, eSAGE scores are lower by an average of 1.21 and the decrease is statistically significant (p < 0.0001). For those subjects familiar with smartphones or tablets (one measure of digital proficiency), eSAGE scores are lower by an average of 0.83 points (p = 0.029). With a score 16 and higher being classified as normal, eSAGE had 90% specificity and 71% sensitivity in detecting those with cognitive impairment from normal subjects.

Conclusions

Tablet-based eSAGE shows a strong association with the validated paper SAGE and a neuropsychological battery. It shows no scale bias compared to SAGE. Both have the advantage of self-administration, brevity, four interchangeable forms, and high sensitivity and specificity in detecting cognitive impairment from normal subjects. Their potential widespread availability will be a major factor in overcoming the many obstacles in identifying early cognitive changes.

Trial registration

ClinicalTrials.gov, NCT02544074. Registered on 18 March 2015.

Self-generated learning in people with multiple sclerosis: An extension of Chiaravalloti and DeLuca (2002)

Although memory impairment is common in people with multiple sclerosis (MS), few interventions have been tested to remediate forgetfulness in MS. Chiaravalloti and DeLuca (2002) examined the memory benefit of self-generated encoding over didactic presentation in people with MS and a control group. They found that self-generated encoding enhanced memory of MS patients and a control group alike. The present study extended this finding by examining self-generated encoding in memory-impaired MS patients as well. A control group and MS patients with and without memory impairment learned word-pairs that were either self-generated or didactically presented. All groups remembered more self-generated words than those that were read aloud, and severity of memory impairment failed to moderate this memory benefit. Implications of these findings for cognitive rehabilitation and the nature of memory impairment in MS are discussed.

The effect of propranolol on cognitive flexibility and memory in acute cocaine withdrawal

Upregulated noradrenergic activity occurs early in cocaine withdrawal. Our previous work revealed impaired cognitive flexibility in acute cocaine withdrawal, a cognitive domain that appears to be modulated by noradrenergic activity. Therefore, we wished to determine the effect of beta-adrenergic antagonists on cognitive performance in acute cocaine withdrawal. Eleven subjects acutely withdrawing from cocaine were tested in this pilot study on tasks of cognitive flexibility as well as word fluency, attention, verbal memory, and spatial memory, off and on propranolol in a double-blinded manner. Propranolol significantly benefited certain aspects of cognitive flexibility in acute cocaine withdrawal, and improved some measures of verbal fluency and verbal recall. Cocaine withdrawal treatment is characterized by high failure rates. Further research is needed to determine the role this finding of a reversible cognitive impairment in cocaine withdrawal has in treatment.

Problem Solving Ability in Patients With Mild Cognitive Impairment

BACKGROUND AND OBJECTIVE

It is important to determine which patients with mild cognitive impairment (MCI) are at risk for progression to dementia. The presence of mild impairments not restricted to the domain of memory may suggest such progression. Our goal is to determine how well a visuospatial problem solving task assessing the cumulative burden of frontal and posterior damage differentiates MCI patients from matched controls.

METHODS

Twenty-six patients with MCI [Clinical Dementia Rating (CDR) score of 0.5] and mini-mental state examination (MMSE) scores of at least 24/30, were compared with 20 age and education level matched controls without cognitive impairment. All patients were given the MMSE, Hopkins Verbal Learning Test (HVLT), Boston Naming Test (BNT), Rey Complex Figures copying (RCF), anagrams, and visuospatial problem solving battery (VPS). The VPS is a complex problem solving task, which we predicted would better discriminate patient groups than the relatively simpler tasks.

RESULTS

Differences existed between groups on most tasks, but logistic regression revealed that the VPS discriminated the 2 groups better than the other nonmemory cognitive tests.

CONCLUSIONS

The VPS, a problem solving task assessing the cumulative burden of frontal and posterior damage is more sensitive for detecting nonmemory impairments in MCI than other tasks. Future research will be needed to determine if impairment in the VPS is a sensitive predictor of progression to dementia or treatment response.

The stability of neurocognitive patterns in HIV infected men: classification considerations

For the neuropsychological impairment which takes place in HIV-1 infection, various classification systems, based on either neuropathological criteria, severity of the disorder or functional criteria, have been suggested in the literature. This study identifies the patterns of neurocognitive disorders in HIV-1 infection and investigates their stability at one-year follow-up. Two hundred and seventeen HIV-1-positive subjects in various stages of infection and 55 HIV-1-negative subjects were evaluated. Our results suggest that there is considerable diversity in the neuropsychological functioning of HIV patients but the patterns are relatively stable, functionally distinct, and differ with respect to the severity of the deficit. The overall pattern is consistent with existing neuropsychological knowledge on HIV infection. Comparison of the patterns identified in this study with other classification systems posed several problems, however, and these problems may have important implications for the theory and methodology of neuropsychological HIV research.

The relationship between age and cognitive function in HIV-infected men

Several studies have identified increased age as a risk factor for the development of cognitive impairment in human immunodeficiency virus (HIV)-infected subjects, but few have examined the potential synergistic effect of age and HIV serostatus on cognitive decline. The authors examined the possible combined effect of age and HIV serostatus on cognitive decline in 254 subjects stratified by age group and HIV status. After controlling for the effect of education, there were significant effects for serostatus and age group on overall cognitive impairment and a number of neuropsychological measures but no interaction effects. These data suggest that older seropositive individuals are not at an increased risk for HIV-related cognitive impairment when normal age-related cognitive changes are considered.

Marijuana use and cognitive function in HIV-infected people

The effect of marijuana use on cognitive function is controversial. Although marijuana use is common in HIV-infected individuals for recreational and medicinal purposes, there have been no studies of the impact of marijuana on cognitive function in these subjects. Marijuana also has known immunologic effects, which increases the relevance in HIV-infected patients. We examined the interaction of HIV disease-stage and marijuana use in 282 subjects, stratified by disease stage and frequency of marijuana use. After controlling for the effects of depression, anxiety, and alcohol use, a significant interaction was observed on an overall measure of cognitive impairment. The effect of marijuana use was greatest in subjects with symptomatic HIV infection. Further inspection suggested that this effect was due primarily to performance on memory tasks. These data suggest that although there is minimal impact of marijuana on uninfected individuals or those at early stages of HIV infection, there is a synergistic effect of HIV and marijuana use in patients with advanced HIV disease. This is consistent with other data suggesting that the subtle effects of some conditions may become more manifest in the setting of immunocompromise.

Effect of Anxiolytics on Cognitive Flexibility in Problem Solving

OBJECTIVE

Our purpose is to examine the effect of different classes of anxiolytics on cognitive flexibility.

BACKGROUND

Situational stressors and anxiety impede performance on "creativity" tests requiring cognitive flexibility. Noradrenergic agents have been shown to modulate cognitive flexibility as assessed by performance on anagrams. To determine whether these findings on noradrenergic modulation of cognitive flexibility are specific to the noradrenergic system or are a nonspecific anxiety effect, we compared the effects of propranolol, lorazepam, and placebo on the anagram task.

METHODS

Subjects attended 3 test sessions. Prior to each session, subjects were given 1 of the 3 drugs. As in previous research, the natural log of the solution latency of each test item was summed for each test session and compared across drug conditions.

RESULTS

For subjects able to solve the anagrams, solution times after propranolol, but not lorazepam, were significantly lower than after placebo.

CONCLUSIONS

Therefore, this suggests that the phenomenon of noradrenergic modulation of cognitive flexibility does not result from a nonspecific anxiolytic effect, but rather is specific to the noradrenergic system.

The effect of previous alcohol abuse on cognitive function in HIV infection

OBJECTIVE

The authors' goal was to study the potential effect on cognitive function of an interaction of HIV infection and a history of alcohol abuse.

METHOD

The subjects were 30 HIV-negative and 50 HIV-positive men with and without a past history of alcohol abuse. Thirty-three of the men (12 HIV negative and 21 HIV positive) had a past history of alcohol abuse, and 47 (18 HIV negative and 29 HIV positive) had never abused alcohol. Each subject's history of alcohol use was obtained by using a syndromal approach based on the Structured Clinical Interview for DSM-III-R and a quantitative approach. Each subject was given a battery of neuropsychological tests assessing verbal reasoning, reaction time, intelligence, memory, and dexterity. The subjects were then compared on a summary neuropsychological impairment rating.

RESULTS

There were no significant differences in CD4 level, age, education, depression, anxiety, or other drug abuse history between the HIV-positive and HIV-negative groups with and without a history of alcohol abuse. Significant effects on cognitive function were found for past alcohol abuse and HIV infection, with significant interactions in verbal reasoning, auditory processing, and reaction time. This demonstrates that HIV infection and a history of alcohol abuse have independent effects on some aspects of higher cognitive function but may have synergistic effects on other cognitive domains. In the HIV-negative subjects there were no differences in cognitive function between subjects with and without a history of alcohol abuse. Among the HIV-positive subjects, those with a history of alcohol abuse performed more poorly on tests of verbal IQ, verbal reasoning, and reaction time.

CONCLUSIONS

There are both additive and interactive effects of previous alcohol abuse and HIV infection on cognition. Individuals with a history of past alcohol abuse may be at greater risk for cognitive dysfunction in the context of HIV infection.

The relationship between stressful life events and cognitive function in HIV-infected men

Previous studies have demonstrated an impact of stress on immune function, and recent studies have suggested an adverse effect of stress on the brain. However, no previous study has examined the impact of stress on cognitive function. This article examines the relationship between stress and cognitive function in 82 HIV-negative subjects and 251 HIV-positive subjects. Subjects completed a comprehensive neuropsychological examination, measures of anxiety and depression, and a measure of stressful life events. After controlling for the impact of anxiety, depression, age, and education, stressful life events were related to cognitive impairment only among the HIV-positive subjects. The data were interpreted in the context of previous studies that have demonstrated an adverse effect of stress on the brain and suggest that this adverse impact may be expressed in the setting of a compromised immune system. Furthermore, this analysis suggests several implications for patient management.

Effects of past noninjection drug abuse upon executive function and working memory in HIV infection

Interactive effects of past noninjection drug abuse/dependence and HIV disease status upon measures of executive function were assessed in a group of 294 homosexual men. Participants were stratified according to HIV status and substance use diagnoses, thereby yielding a 4 (seronegative, asymptomatic seropositive, symptomatic seropositive, and AIDS defining illness) x 2 (never abused drugs, previous substance use disorder) design. Significant main effects of HIV status were found on the Wisconsin Card Sorting Test, Ruff Figural Fluency Test, Trail Making Test B, and total number of impaired performances. Analyses revealed that men with AIDS defining illness performed worse than the other three groups. Drug use history had no significant effect upon neurobehavioral function, and effect sizes for drug abuse history were small. The data suggest that prior drug use yields little if any residual cognitive impairment in HIV infection.

Central beta-adrenergic modulation of cognitive flexibility

Situational stressors and anxiety impede performance on creativity tests requiring cognitive flexibility. Preliminary research revealed better performance on a task requiring cognitive flexibility, the anagram task, after propranolol (beta-adrenergic antagonist) than after ephedrine (beta-adrenergic agonist). However, propranolol and ephedrine have both peripheral and central beta-adrenergic effects. In order to determine whether noradrenergic modulation of cognitive flexibility is a centrally or peripherally mediated phenomenon, we compared the effects of propranolol (peripheral and central beta-blocker), nadolol (peripheral beta-blocker), and placebo on anagram task performance. Solution latency scores for each subject were compared across the drug conditions. Anagram solution latency scores after propranolol were significantly lower than after nadolol. This suggests a centrally mediated modulatory influence of the noradrenergic system on cognitive flexibility.

Neuropsychological impairment among manic, depressed, and mixed-episode inpatients with bipolar disorder

Previous research has demonstrated broad neurobehavioral abnormalities in bipolar affective disorder (cf. G. Cassens, L. Wolfe, & M. Zola, 1990). However, there have been no comparisons of neuropsychological function across patients with manic, depressed, or mixed subtypes. In the present study, 37 manic, 24 mixed-episode, and 25 depressed bipolar I inpatients and 34 control subjects were administered a brief battery of neuropsychological tests. The multivariate and univariate effects of participant group on the neuropsychological measures were uniformly significant (p < .05). Planned contrasts revealed that the bipolar participants performed worse than the controls, and few differences existed between the 3 patient groups. Additionally, the bipolar groups were impaired on 50% of the test battery. These abnormalities were unlikely attributable to differences in psychiatric symptomatology, medical illness, comorbid psychiatric diagnoses, or medication status. Findings imply that acute mood disturbance during bipolar disorder yields significant neurobehavioral dysfunction.

Practice effects on the Wisconsin Card Sorting Test-64 Card version across 12 months

The Wisconsin Card Sorting Test (WCST: Heaton, Chelune, Talley, Kay, & Curtiss, 1993) is among the most commonly administered measures of executive function. Recently, a short form of the test was developed (WCST-64: Kongs, Thompson, Iverson, & Heaton, 2000), and it affords psychometric properties commensurate with the full version of the test. Yet, similar to other measures of executive function, relatively little is known concerning the effects of repeated administration on the WCST-64. Towards this end, 53 men (age M = 32.38) were administered the WCST-64 twice over 12 months, and scores on several indices improved significantly during this interval. Suggestions concerning the use of these measures in longitudinal research designs and clinical follow-up examinations are offered, and reliable change indices concerning these measures are included.

Depression accounts for executive function deficits in obsessive-compulsive disorder

OBJECTIVE

To examine the relative impact of depression on executive function deficits in obsessive-compulsive disorder (OCD).

BACKGROUND

Existing data suggest that OCD is associated with basal ganglia and orbital frontal dysfunction, and neurobehavioral abnormalities that are putatively associated with these regions have been demonstrated in OCD. Nonetheless, few studies have accounted for the effects of depression, which is a common concurrent symptom among those with OCD.

METHOD

A broad battery of neuropsychological tests, including measures of executive function and sensory-motor function, was administered to 20 adults with OCD and 31 control subjects. To assess depressive severity, participants were administered the depression scale from the Minnesota Multiphasic Personality Inventory.

RESULTS

Data were analyzed using a regression model in two steps. In step one, patient group was entered, and patients with OCD demonstrated a pattern of executive function and sensory-motor deficits, similar to those shown in previous research. In step two, self-reported depressive symptom severity was entered as a predictor. As a consequence, depression accounted for some executive function deficits, whereas presence of OCD only predicted performance on measures of sensory-motor function.

CONCLUSIONS

These data suggest that abnormalities involving executive function in OCD are related to co-morbid depressive severity. However, sensory-motor deficits seem to be more consistent with basal ganglia/orbital frontal dysfunction in OCD.

Neurobehavioural consequences of substance abuse and HIV infection

Although our understanding of how human immunodeficiency virus (HIV)-related neurobehavioural deficits develop is nascent and preliminary, some clues have emerged which may clarify lingering uncertainties. In particular, HIV seems to yield brain dysfunction by mediating pathological changes upon neuronal function. HIV also compromises immunological integrity, thereby resulting in secondary infections that may further increase brain dysfunction. Notably, many individuals with HIV tend to be current or past abusers of drugs, and, in some cases, their drug use may have actually presented a pathway for initial HIV infection. Similar to HIV, many drugs tend to yield pathological changes upon neuronal function. Further paralleling HIV, some drugs seem to compromise immune function, which in turn may yield secondary detrimental effects upon the brain. Yet, despite the relatively high comorbidity rates of HIV infection and substance abuse, few investigations have addressed the potential interaction between these two factors upon neurobehavioural status. Towards this end, the present paper reviews the existing literature concerning neuropsychological effects of HIV and substance use, and suggests potential mechanisms whereby substance use may potentiate and exacerbate the onset and severity of neurobehavioural abnormalities in HIV infection.

Neuropsychological performance in asymptomatic HIV infection

This study compared 74 human immunodeficiency virus (HIV)-negative and 131 HIV-positive asymptomatic homosexual or bisexual men on an extensive neuropsychological test battery. HIV-positive subjects' performance was significantly worse on verbal memory and psychomotor skills. The prevalence of mild but persistent neurobehavioral impairment in the HIV-positive group was approximately twice that in HIV-negative patients, consistently across several criteria for impairment. There was evidence that degree of neuropsychological impairment was related to patients' perceptions of dysfunction in daily life. Findings were not related to degree of depression or to medication effects. These data suggest that approximately 10% to 20% of HIV-positive asymptomatic men suffer mild neuropsychological impairment that influences their daily lives.

Limited accuracy of premorbid intelligence estimators: a demonstration of regression to the mean

Regression-based premorbid intelligence estimators have been devised by Barona, Reynolds, and Chastain (1984), Barona and Chastain (1986), Hamsher (1984), Krull, Scott, and Sherer (1995; the Oklahoma Premorbid Intelligence Estimate: OPIE), and Vanderploeg, Schinka, and Axelrod (1996; BEST-3 approach), but little is known of their relative accuracy, particularly in outer ranges of intellectual ability (e.g., below-average, superior, etc.). Towards this end, the Wechsler Adult Intelligence Scale-Revised (WAIS-R) was administered to 150 neurologically normal adults, and estimated VIQ, PIQ, and FSIQ scores were computed according to each regression method. Results showed that methods based solely on demographic factors were most susceptible to meanward regression, rendering them poor estimators of IQ scores in outer ranges. Although the OPIE and BEST-3 performed somewhat better, their accuracy remained relatively weak. The findings suggest that regression-based estimates of premorbid IQ are very susceptible to error, particularly in outer ranges of intellectual function.

Estimated premorbid intelligence mediates neurobehavioral change in individuals infected with HIV across 12 months

This study tested whether estimated premorbid intelligence moderates worsening neurobehavioral dysfunction in HIV infection. 155 homosexual men (54 controls, 49 HIV+ asymptomatic, 24 HIV+ symptomatic, 28 AIDS) with stable disease status were tested on measures of executive function at baseline and 12-month follow-up. Premorbid intelligence was estimated on the basis of a demographically-based regression equation (Hamsher, 1984), and participants were classified as average or above-average intelligence. Regardless of disease status, participants with above-average IQ showed no declines on measures of executive function across time. In contrast, among those with average IQ, symptomatic groups showed declines, whereas the asymptomatic group did not. The findings support the hypothesis that estimated premorbid intelligence mediates declines in neuropsychological function in patients with stable HIV status. These findings are consistent with theoretical models of cognitive reserve capacity.

Effects of immunosuppression and disease severity upon neuropsychological function in HIV infection

Effects of immunosuppression and illness severity upon neuropsychological function were assessed in a group of homosexual men with AIDS across 6 months. Participants included 62 who were seronegative (HIV-), 74 asymptomatic seropositives (HIV+A), 31 symptomatic seropositives (HIV+S), 23 with AIDS defining illnesses (AIDS-DI), and 10 who were diagnosed with AIDS solely on the basis of CD4+ levels falling below 200 /mm3 (AIDS-CD4). Groups were equivalent in age, education, and IQ. None were drug users, and none experienced a change in disease status across the 6-month inter-test interval. There was little evidence of cognitive decline across time. Nonetheless, after collapsing across time intervals, the AIDS-DI group had worse new-learning than all other groups. Additionally, the AIDS-DI demonstrated a greater number of impaired performances than the other participant groups. The data suggest that cognitive impairment in AIDS is unlikely due to independent contributions of immunosuppression and illness. Rather neurobehavioral deficits are more likely attributable to a combination of the two.

Relative memory deficits in recurrent versus first-episode major depression on a word-list learning task

Although memory deficits are associated with major depressive disorder, few studies have identified which patient characteristics predict impairment. Because recurrent depression appears related to more severe cerebral dysfunction, the present study tested whether recurrent depressed individuals have worse memory function than first-episode depressed individuals. Two groups of young-adult, nonpsychotic, depressed inpatients (20 single episode [SE] and 46 recurrent episode [RE]) were administered the California Verbal Learning Test within a broader battery of neuropsychological tests. The groups were equivalent in age, education, estimated IQ, severity of depression, and demographic composition. The RE group demonstrated memory deficits relative to both the SE group and published norms, but no other significant difference was found across the battery. Data indicate that abnormal memory performance is associated with recurrent depression, whereas memory deficits are not prominent in first-episode depressed individuals.

Relative memory deficits in recurrent versus first-episode major depression on a word-list learning task

Although memory deficits are associated with major depressive disorder, few studies have identified which patient characteristics predict impairment. Because recurrent depression appears related to more severe cerebral dysfunction, the present study tested whether recurrent depressed individuals have worse memory function than first-episode depressed individuals. Two groups of young-adult, nonpsychotic, depressed inpatients (20 single episode [SE] and 46 recurrent episode [RE]) were administered the California Verbal Learning Test within a broader battery of neuropsychological tests. The groups were equivalent in age, education, estimated IQ, severity of depression, and demographic composition. The RE group demonstrated memory deficits relative to both the SE group and published norms, but no other significant difference was found across the battery. Data indicate that abnormal memory performance is associated with recurrent depression, whereas memory deficits are not prominent in first-episode depressed individuals.

Practice effects on commonly used measures of executive function across twelve months

Fifty men (age M = 32.50; education M = 14.98 years) were administered the Wisconsin Card Sorting Test (WCST), Ruff Figural Fluency Test (FFT), Verbal Concept Attainment Test (VCAT) Trail Making Test, Parts A and B (TMT), and F-A-S Verbal Fluency at baseline and 12 months later. WCST, FFT, and VCAT scores improved significantly over a 12-month interval. In contrast, TMT and F-A-S scores did not change. Level of intellectual ability failed to moderate the effect of previous testing upon performance. Suggestions concerning the use of these measures in longitudinal research designs and clinical follow-up examinations are offered, and reliable change indices concerning these measures are included.

Neuropsychological deficits in psychotic versus nonpsychotic unipolar depression

A broad range of neuropsychological function was compared in samples of young adult unipolar depressed inpatients with and without psychotic features. Consistent with expectations, the psychotic depressive group demonstrated a broad range of deficit and had more impaired performances than the nonpsychotic group. Relevance of these data for hypotheses concerning psychotic depression as a unique diagnostic entity is discussed. In the context of previous research, the current findings suggest that accounting for individual differences in depression may clarify discrepancies between earlier studies of neuropsychological function in depression, and our understanding of the mechanisms by which depression influences cognition may be refined.

Neuropsychological deficits in psychotic versus nonpsychotic unipolar depression

A broad range of neuropsychological function was compared in samples of young adult unipolar depressed inpatients with and without psychotic features. Consistent with expectations, the psychotic depressive group demonstrated a broad range of deficit and had more impaired performances than the nonpsychotic group. Relevance of these data for hypotheses concerning psychotic depression as a unique diagnostic entity is discussed. In the context of previous research, the current findings suggest that accounting for individual differences in depression may clarify discrepancies between earlier studies of neuropsychological function in depression, and our understanding of the mechanisms by which depression influences cognition may be refined.

Neuropsychological correlates of negative, disorganized and psychotic symptoms in schizophrenia

Recent studies suggest that three dimensions (negative, disorganized and psychotic) categorize schizophrenic symptoms. A developing literature indicates distinct cerebral correlates of each symptom cluster, but few investigations have determined their neuropsychological correlates. In the present study, the Schedules of Negative and Positive Symptoms measured symptom severity in 62 schizophrenics, and a subsequent principal components analysis revealed three symptom dimensions. Factor scores, age and parental socio-economic status were simultaneously entered into regression equations to explain variance across a broad neuropsychological test battery. Negative symptoms were associated with deficits involving intelligence, executive function, memory, sustained-attention and sensory-motor function, whereas disorganized symptoms correlated with decreased intelligence, attention-span and sensory-motor function. Psychotic symptoms were unrelated to deficits. These data are consistent with hypotheses that these three symptom dimensions have distinct neurobehavioral correlates.

Impaired neuropsychological functioning in Tourette's syndrome subjects with co-occurring obsessive-compulsive and attention deficit symptoms

This study examined neuropsychological performance by 92 children with Tourette's syndrome (TS) grouped by the presence or absence of obsessive-compulsive and/or attention deficit symptoms. The identified groups did not differ with respect to age, education, age at onset of TS symptoms, or medication use. After statistical control for complex motor symptoms, impaired performance on measures of achievement and executive functioning was correlated with obsessive and obsessive/attention symptoms, but not with attention symptoms alone. The presence of both obsessive and attention symptoms identified children with impairment across several tasks. Clinical and functional implications are discussed.

Cognitive deficits distinguish patients with adolescent- and adult-onset schizophrenia

Recent studies have shown that patients with schizophrenia who have an adolescent-symptom onset (before age 21) have a worse clinical course and greater frequency of cerebral abnormalities than those with an adult-onset (after age 25). However, little is known about the neuropsychological functioning of these groups. A comprehensive neuropsychological examination was administered to groups of patients with schizophrenia with either an adolescent- or adult symptom-onset and a healthy control group. The adolescent-onset group performed worse than the adult-onset and control groups, particularly on measures of memory and executive function. The adult-onset group also performed worse than the controls, but to a lesser extent than did the adolescent-onset group. Results are discussed with reference to hypotheses that adolescent-onset schizophrenia represents a distinct neurodevelopmental disease entity.

Screening for cognitive dysfunction in multiple sclerosis

BACKGROUND

With the use of comprehensive neuro-psychological assessments, a substantial proportion of patients with multiple sclerosis have been found to have substantial cognitive impairment. Although data generated from comprehensive examinations are useful in making recommendations for treatment interventions and compensatory strategies, the cost of such assessments prohibits their use with all patients.

OBJECTIVE

To develop a screening battery to detect cognitive impairment in patients with multiple sclerosis that is sensitive, specific, brief, and cost-effective, and could identify patients who might benefit from a more comprehensive neuropsychological examination.

DESIGN

On the basis of a comprehensive neuropsychological assessment battery, the presence of significant cognitive impairment was determined in patients with multiple sclerosis. The screening battery consisted of a subset of tests from the comprehensive battery. Performance on the screening battery was then used to predict presence of cognitive impairment on the comprehensive battery in validation and cross-validation samples. Severity of impairment on the screening battery was also regressed on ratings of functional impairment derived from the Expanded Disability Status Scale.

RESULTS

In the validation sample, the screening battery had 100% sensitivity, 80% specificity, and 88.1% overall diagnostic accuracy. In the cross-validation sample, the screening battery had 100% sensitivity, 81.8% specificity, and an overall diagnostic accuracy rate of 90.7%. chi 2 tests showed that the accuracy of the screening battery was significantly better than chance in both samples. Performance on the screening battery also predicted the level of disability ratings on the Expanded Disability Status Scale and functional systems scales.

CONCLUSIONS

The screening battery had a high degree of sensitivity, specificity, and diagnostic accuracy, while maintaining a brief administration time and high cost-effectiveness. The screening battery also predicted higher levels of disability and functional impairment as assessed by the Expanded Disability Status Scale, thereby enhancing its clinical utility. Despite its advantages, the findings do not suggest that the screening battery may be an effective substitute for a more detailed examination.

Neuropsychological correlates of learning disability subtypes in children with Tourette's syndrome

Neuropsychological deficits in Tourette's syndrome (TS) may be associated with learning disabilities. We examined the neuropsychological performance of 70 children with TS between the ages 6 and 18 years who were classified into four groups based on their pattern of performance on the Wide Range Achievement Test-Revised. The groups included three learning disability subtypes and a nonlearning disabled comparison group. The groups differed significantly on several measures in a comprehensive neuropsychological test battery. The pattern of differences was not entirely consistent with previous research, however, suggesting that neuropsychological correlates of learning disabilities may be influenced by the specific pathophysiology associated with TS. Thus, previous research on the neuropsychology of learning disability subtypes might not be generalizable to children with discrete neuropsychiatric disorders such as TS.

Neuropsychological function in patients with end-stage heart failure before and after cardiac transplantation

This study was performed to examine cognitive function in patients with end-stage heart failure, to identify possible cardiovascular factors associated with cognitive function, and to evaluate changes in cognitive function in a subgroup of patients who received heart transplantation. An extensive battery of neuropsychological tests were given to 62 patients with end-stage cardiac failure as part of their evaluation for cardiac transplantation. Most patients were consecutive referrals, not selected because of cognitive complaints. A small subgroup of transplanted (n = 7) and non-transplanted (n = 4) patients received a repeat neuropsychological examination. At initial examination, approximately 50% of the patients met criteria for impairment in reference to normal control values. Higher stroke volume index and cardiac index and lower right atrial pressure were correlated with better cognitive function. In the subgroup of patients re-examined, the transplanted patients demonstrated significantly improved cognitive function, whereas the non-transplanted subjects were unchanged. These data indicate that in patients with end-stage heart failure there is a high prevalence of impaired cognitive function which is related to measures of cardiovascular efficiency. Preliminary evidence suggests that these impairments may be partially ameliorated by cardiac transplantation.

Obsessive-compulsive symptom clusters and urinary amine correlates in Tourette syndrome

This study was conducted to identify clusters of obsessive-compulsive characteristics in Tourette syndrome subjects and to explore their neurochemical correlates. Patients completed a 40-item questionnaire assessing obsessive-compulsive symptoms. Each subject had a 24-hour urine specimen collected and analyzed for a variety of biogenic amines and their metabolites. Factor analysis identified eight symptom clusters, the majority of which appeared to reflect obsessive symptoms. Consistent relationships were observed between symptom clusters and levels of catecholamine and indolamine amines and metabolites. Overall, the primary metabolite of serotonin, 5-hydroxyindoleacetic acid, appeared to be the most highly correlated with the individual obsessive-compulsive symptoms.

Neurochemical and some related psychopharmacological aspects of Tourette's syndrome: an update

Neurochemical investigations of Tourette's syndrome (TS) suggest that the symptoms of this disorder may be the result of an imbalance among several neurotransmitter and/or neuromodulator systems. Neurochemicals which have been studied included: catecholamines; acetylcholine; tryptophan and its metabolites; the amino acids γ-aminobutyric acid (GABA), glutamate, phenylalanine and p-tyrosine; trace amines; opioid peptides; cyclic AMP and androgenic hormones. A suitable animal model of TS would do much to advance our understanding of this disorder, and there are some interesting recent developments in this regard.

Clinical predictors of psychopathology in children and adolescents with Tourette Syndrome

Tourette Syndrome (TS) is a neuropsychiatric disorder of childhood onset characterized by vocal and motor tics and associated psychopathologies. The current study was undertaken to explore the associations between tic symptomatology, related clinical variables and behavioral dysfunction within a cohort of TS subjects. Ninety-two child and adolescent TS subjects were rated through self-measure, and by parents on measures of tic symptomatology, OC characteristics, and dysfunctional behaviors including learning difficulties and attention deficits. Statistical modeling revealed associations among tic clusters, clinical items and behavioral measures, which were unique for the child and adolescent subgroups.

The course of tics in Tourette syndrome: a 5-year follow-up study

The current study was undertaken to explore the course of tics in Gilles de la Tourette's syndrome (TS). As part of a prospective 5-year follow-up of non-clinically based TS subjects who had originally participated in a comprehensive research protocol, 23 subjects (ages 11 to 53 years) were reevaluated for tics and obsessive-compulsive (OC) characteristics. Three (13%) of the subjects had an improvement in total tic symptomatology, while 15 (65.2%) had no change and 5 (21.7%) worsened. Improvement or worsening was independent of baseline developmental age across child, adolescent, and adult subgroups. Complex motor tics at baseline predicted complex motor tics and simple phonic tics at follow-up. Baseline OC and complex motor tics independently predicted subsequent OC and complex motor symptoms. Data from the current study provide evidence of the stability of tic subtypes over time and developmental period.

Neuropsychological performance and CD4 levels in HIV-1 asymptomatic infection

The performance of 68 HIV-1 seropositive asymptomatic (HIV+) subjects stratified on CD4 levels were compared with 82 HIV-1 seronegative (HIV-) subjects on a battery of neuropsychological, mood state, and perceived health status measures. The neuropsychological test battery included measures of attention, reaction time, memory, intellectual ability, psychomotor speed, frontal lobe or "executive" function, and decision time. None of the HIV+ subjects were taking antiviral agents. The groups did not differ for age, mood state, or WAIS-R Verbal and Performance IQ scores. Due to group differences for education and weekly ethanol consumption, both variables were used as covariates in multivariate analyses of variance. Relatively few differences were observed between subgroups of HIV+ patients or between these subgroups and control subjects. These data suggest that factors other than absolute levels of immunosuppression as expressed by CD4 levels alone, appear to be responsible for the deficits observed in HIV+ asymptomatic patients.

Obsessive characteristics in subjects with Tourette's syndrome are related to symptoms in their parents

The symptom characteristics of two Tourette's syndrome (TS) subgroups formed on the basis of their parents' obsessive-compulsive (OC) symptomatology were explored. TS subjects with parents having OC symptoms had significantly more OC symptoms and complex tics and a later age of symptom onset than the balance of the TS cohort. These findings suggest an association between parental OC symptoms and OC symptoms in their TS offspring.

Patterns of obsessive compulsive symptoms in Tourette subjects are independent of severity

Studies have examined the expression of obsessive compulsive (OC) symptoms in obsessive compulsive disorder (OCD), OCD with co-occurring Tourette's Syndrome (TS) or chronic motor tic disorder (CMT) and TS alone. In adult samples, there appears to be a relatively consistent OC symptom thematic content that characterizes OCD alone and OCD in conjunction with tics or TS. Previous studies have controlled for the severity of OC symptoms in OCD and TS groups. In the current study, it was our objective to determine whether patterns of OC symptoms in TS are independent of OC symptom severity. The current exploratory study examined OC symptom expression in a nonclinically based TS sample with a broad range of OC symptoms and severity and a selected clinical OCD sample without TS/tics. Univariate and multivariate statistical analysis explored patterns of OC symptom expression between the two groups. Similar to previous reports examining OC symptoms in OCD and OCD with TS/tics, subjects with OCD alone were characterized by contamination obsessions and cleaning compulsions. In contrast, TS subjects had more somatic, sexual and symmetry obsessions and more checking, counting and touching/blinking compulsions, independent of OC symptom and tic severity. A discriminant function using obsessive items alone correctly grouped 91.4% of cases. The current study replicates patterns of OC symptom expression unique to OCD alone. Patterns of OC symptoms, in particular obsessive symptoms, can robustly predict membership in OCD or TS groups, even with a substantial variation in OC symptom severity as measured by the Y-BOCS score.

Duration of illness and neuropsychological performance in asymptomatic HIV infection

The relationship between duration of illness and neuropsychological performance was examined in 25 asymptomatic HIV-infected men with an estimated date of seroconversion. Mean duration of illness was approximately 2 years. After controlling for CD4 level at the time of neuropsychological examination, duration of illness was correlated with measures of visual attention, mental flexibility, dexterity, auditory information processing, and response fluency, as well as an overall measure of neuropsychological performance. Although these patients performed within normal limits, these data suggest that duration of infection may be related to subtle alterations in neuropsychological performance. These results are discussed with regard to possible mechanisms that implicate gradual accumulation of neurotoxins.

Self-report of symptoms and neuropsychological performance in asymptomatic HIV-positive individuals

This study examined the relationship between subjective complaints and neuropsychological performance in 133 HIV-positive asymptomatic and 80 HIV-negative gay or bisexual men. Presence and duration of self-reported symptoms were most strongly related to measures of information processing and reaction time. These relationships remained significant when the effect of depression was statistically controlled, and no significant relationships were found between CD4 level and either presence or duration of symptoms. These data suggest that 1) depression does not completely account for the relationship between subjective complaints and neuropsychological performance and 2) early subjective recognition of symptoms may represent a risk factor for subsequent development of neurobehavioral abnormalities.

Change in neuropsychological performance in asymptomatic HIV infection: 1-year follow-up

OBJECTIVE

To examine the stability of cognitive function in patients with asymptomatic HIV infection.

DESIGN

Previous longitudinal studies of cognitive function have focused on patients who progress in terms of disease stage. The present study avoided this potential confounding factor by including only subjects who remained in the asymptomatic stage of infection over the follow-up period.

METHOD

Subjects were administered an extensive neuropsychological test battery at baseline and 1 year follow-up. Overall performance was characterized as normal or abnormal based on the performance of a well-matched HIV-negative control group.

RESULTS

A significantly higher proportion of HIV-positive subjects became abnormal at the follow-up examination. Comparison of the seropositive subjects who remained normal with those who became abnormal revealed no differences at baseline on age, education, depression or CD4 levels. Subjects who became abnormal had worse performance at baseline on measures of information processing, verbal learning and memory, and reaction time.

CONCLUSIONS

These data indicate that cognitive function may decline in some patients who continue to be in the asymptomatic stage of infection. Patients with a pattern of cognitive abnormalities at baseline, which includes information processing and reaction time deficits, may be at increased risk for declines in function during early stages of infection.

Trace amines and Tourette's syndrome

There has been considerable interest in recent years in possible neurochemical abnormalities in Tourette's Syndrome (TS). In studies combining neuropsychological and neurochemical measurements, we have investigated the possible roles of trace amines in this disorder. Urinary levels of free beta-phenylethylamine (PEA) and plasma levels of its precursor amino acid phenylalanine were decreased in TS patients when compared to values in normal children. These urinary PEA levels in TS patients were inversely related to several scores from the Tourette's Syndrome Global Scale (TSGS). Further investigation of the group of subjects with low urinary PEA indicated that they also had low levels of MHPG, normetanephrine, 5-HT and m- and p-tyramine. Patients with low PEA were also compared on an extensive battery of neuropsychological measures and observed to perform significantly worse than TS patients with normal urinary PEA levels. Biochemical measurements also suggest a possible abnormality in tryptamine turnover in TS since urinary levels of indole-3-acetic acid (IAA; the acid metabolite of tryptamine) are significantly lower in TS patients than in normal controls.