Publications (8)40.75 Total impact
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Article: No, it is not possible to be schizophrenic yet neuropsychologically normal.
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ABSTRACT: Cognitive impairment is well documented in schizophrenia, though some reports have been interpreted to suggest that it is possible to have schizophrenia without neuropsychological impairment. The authors tested this by comparing the neuropsychological profiles of closely matched patients with schizophrenia and healthy comparison participants. Sixty-four patients with schizophrenia and 64 healthy comparison cases, matched to within 3 Full-Scale IQ points, were tested using the Wechsler Adult Intelligence Scale (3rd ed.; D. Wechsler, 1997b) and the Wechsler Memory Scale (3rd ed.; D. Wechsler, 1997c). Neuropsychological profiles for these groups were markedly different, with the group of patients with schizophrenia exhibiting performance deficits in memory and speeded visual processing but superior verbal comprehension and perceptual organization relative to the group of healthy comparison participants matched on Full-Scale IQ. Thus, scoring in the normal range does not preclude neuropsychological abnormality in schizophrenia, confirming that neuropsychological impairment is a core feature of the illness.Neuropsychology 12/2005; 19(6):778-86. · 3.82 Impact Factor -
Article: Brief cognitive assessment in schizophrenia: normative data for the Repeatable Battery for the Assessment of Neuropsychological Status.
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ABSTRACT: The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) is a brief, standardized cognitive screening instrument that assesses several domains of interest and offers an efficient approach to screening for cognitive impairment in schizophrenia (SC). Prior studies have established the clinical validity and test-retest reliability of the RBANS in SC. The purpose of the current study was to guide clinical interpretation by providing normative data for the use of the RBANS as a measure of cognitive impairment in SC. We also sought to evaluate the role of demographic factors and to present percentile data accordingly. 575 patients (391 male, 184 female) meeting the diagnostic criteria for SC or schizoaffective disorder were recruited from 4 inpatient (n=117) and 6 outpatient (n=458) sites in 2 different mental health treatment systems. All participants were administered the RBANS according to standardized instructions and a subgroup of 242 patients were also administered the Wide Range Achievement Test (3rd Edition) (WRAT-3) Reading subtest. RBANS Total Scale score for patients with SC was approximately 2 standard deviations below the normal mean, was approximately 1 standard deviation below WRAT-3 Reading scores, and expected patterns of impairment were observed: measures of language and visuospatial ability were preserved relative to those of memory and attention. Aside from weak associations with Language (0.139) and Attention (0.112), age was not significantly associated with RBANS Index scores (which are age adjusted in healthy controls). Education was significantly associated with all RBANS scores and one-way ANOVA indicates that those with more than high school education scored consistently higher than the other two groups (less than and equal to a complete high school education). Normative tables with age and education based percentiles are presented. The RBANS is an efficient screening tool for assessing cognitive impairment in patients with SC thereby making it a useful instrument for clinical and research applications.Schizophrenia Research 11/2004; 70(2-3):175-86. · 4.75 Impact Factor -
Article: Assessment of depression prevalence in rural Uganda using symptom and function criteria.
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ABSTRACT: We sought to assess the prevalence of major depression in a region of sub-Saharan Africa severely affected by HIV, using symptom and functional criteria as measured with locally validated instruments. Six hundred homes in the Masaka and Rakai districts of southwest Uganda were selected by weighted systematic random sampling. A locally validated version of the depression section of the Hopkins Symptom Check List (DHSCL) and a community-generated index of functional impairment were used to interview 587 respondents. Of respondents, 21% were diagnosed with depression using three of the five DSM-IV criteria (including function impairment) compared with 24.4% using symptom criteria alone. Increased age and lower educational levels are associated with a greater risk for depression; however, a gender effect was not detected. Most community-based assessments of depression in sub-Saharan Africa based on the DSM-IV have used symptom criteria only. We found that expanding criteria to more closely match the complete DSM-IV is feasible, thereby making more accurate assessments of prevalence possible. This approach suggests that major depression and associated functional impairment are a substantial problem in this population.Social Psychiatry and Psychiatric Epidemiology 07/2004; 39(6):442-7. · 2.70 Impact Factor -
Article: The family pictures test as a measure of impaired feature binding in schizophrenia.
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ABSTRACT: We investigated the use of the Family Pictures test from the Wechsler Memory Scale III as a measure of the ability to bind the multiple features of a complex visual scene in a study group of 77 patients with schizophrenia and 44 healthy controls. Patients demonstrated impaired recall of all scene features as well as a reduction in the number of features recalled for each remembered character. Secondary analyses using patients and controls matched for character recall also showed reduced feature binding in the patient group. Such feature binding deficits likely implicate hippocampal dysfunction, consistent with neuroimaging evidence of structural and functional compromise of the medial temporal lobe in schizophrenia.Journal of Clinical and Experimental Neuropsychology 06/2004; 26(4):511-20. · 2.13 Impact Factor -
Article: General and specific cognitive deficits in schizophrenia.
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ABSTRACT: It is controversial whether the cognitive deficit in schizophrenia is better characterized as generalized or as reflecting relatively independent deficits in different cognitive domains. The issue has implications for assessment practice, intervention design, and the exploration of schizophrenia genetics. We used a specialized structural equation modeling approach, single common factor analysis, to explore the relative importance of generalized versus independent cognitive deficits in schizophrenia. Eighteen subtest scores from the Wechsler Adult Intelligence Scale-III and the Wechsler Memory Scale-III were included in the analysis. We analyzed these data for 97 schizophrenia or schizoaffective disorder outpatients and 87 healthy control subjects. Approximately two thirds of the overall effect of a schizophrenia diagnosis on cognitive performance was mediated through a single common factor. The Wechsler subtest scores showed almost uniformly strong relationships with this factor. The independent associations of group status with the subtest scores were smaller in magnitude and only selectively significant. The relatively greater magnitude of illness effects mediated through the common factor in this analysis, compared with the specific, independent effects, suggests that a generalized cognitive deficit is a core feature of schizophrenia.Biological Psychiatry 05/2004; 55(8):826-33. · 8.28 Impact Factor -
Article: Working memory for visual features and conjunctions in schizophrenia.
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ABSTRACT: The visual working memory (WM) storage capacity of patients with schizophrenia was investigated using a change detection paradigm. Participants were presented with 2, 3, 4, or 6 colored bars with testing of both single feature (color, orientation) and feature conjunction conditions. Patients performed significantly worse than controls at all set sizes but demonstrated normal feature binding. Unlike controls, patient WM capacity declined at set size 6 relative to set size 4. Impairments with subcapacity arrays suggest a deficit in task set maintenance: Greater impairment for supercapacity set sizes suggests a deficit in the ability to selectively encode information for WM storage. Thus, the WM impairment in schizophrenia appears to be a consequence of attentional deficits rather than a reduction in storage capacity.Journal of Abnormal Psychology 03/2003; 112(1):61-71. · 4.86 Impact Factor -
Article: Local perceptions of the mental health effects of the Uganda acquired immunodeficiency syndrome epidemic.
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ABSTRACT: Despite much attention in developed countries, little is known about the relationship between mental health problems and the human immunodeficiency virus (HIV) in Africa. The objectives of the current study were a) to investigate how people in an African community severely affected by HIV view the mental health effects of the epidemic and b) to use these data to investigate the local construct validity of the Western concepts of depression and posttraumatic stress disorder. Ethnographic methods-free listing and key-informant interviews-were used among participants from the Rakai and Masaka districts of southwest Uganda. Participants described two independent depression-like syndromes (Yo'kwekyawa and Okwekubaziga) resulting from the HIV epidemic. No syndromes similar to posttraumatic stress disorder were detected. We conclude that local people recognize depression syndromes and consider them pertinent consequences of the HIV epidemic.Journal of Nervous & Mental Disease 07/2002; 190(6):394-7. · 1.68 Impact Factor -
Article: Test-retest stability of the Repeatable Battery for the Assessment of Neuropsychological Status in schizophrenia.
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ABSTRACT: The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) was designed as a cognitive screening test, providing both a total scale score and five specific cognitive ability index scores. This study examined the test-retest stability of the RBANS in individual patients with schizophrenia relative to a healthy comparison group. A total of 181 patients with schizophrenia or schizoaffective disorder were recruited from three clinical settings. Healthy comparison subjects were recruited as part of the RBANS standardization. Participants were administered one form of the RBANS on one occasion and another form at a later date, with intervals ranging from 1 to 134 days. Intraclass correlation coefficients for the RBANS total scale were 0.84 for the patients with schizophrenia and 0.77 for the healthy comparison subjects. Confidence intervals and percentile data for the total scale change scores were similar for both groups. The RBANS demonstrated reasonable intraclass correlation coefficient test-retest reliability for both schizophrenia patients and healthy comparison subjects. Confidence intervals are comparable to those previously published for the WAIS-R and Wechsler Memory Scale-Revised, suggesting that retest measurement error is not dramatically increased in the RBANS, despite the brevity of the test. These data may serve as an informative guide for using the RBANS to evaluate neuropsychological change on the level of the individual subject.American Journal of Psychiatry 06/2002; 159(5):838-44. · 12.54 Impact Factor
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Institutions
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2002–2005
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University of Maryland-School of Medicine
Baltimore, MD, USA
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2004
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University of Maryland, Baltimore
- Department of Psychiatry
Baltimore, MD, USA
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