摘要:

SummaryWe followed a cohort of 223 intravenous drug users (99 HIV and 124 HIV+) for up to 3.5 years, examining change in performance over time as a function of HIV status, disease severity, and neurological signs and symptoms. Analyses were performed by applying generalized estimating equations (GEE) to regression analyses with repeated measures, and controlled for age, education, and length of substance use. None of the subjects had AIDS at baseline. There were 147 men (85 HIV+and 62 HIV) and 76 women (39 HIV+and 37 HIV). Memory performance was worse in the HIV+than HIV−women. In the men, performance on the memory, executive, language, and attention factors improved significantly overtime, but this improvement was attenuated in the HIV men for the attention and orientation factors. In the HIV+women. AIDS was associated with worsening performance on attention tests. The presence or onset of clinically significant neurological findings was associated with poorer language and motor speed performance. In the HIV+men, memory performance was worse when the CD4 count fell below 200: it declined over time in men with AIDS but not in those without. A learning effect for language was attenuated in men who developed AIDS. The presence or development of a clinically significant neurological sign was associated with poorer memory, executive, language, attention, and motor speed performance. Our findings parallel those that we previously reported in a prospectively followed cohort of gay men. In combination, our studies of gay men and IDU cohorts suggest that (a) HIV can affect cognition early, even when the patient is medically asymptomatic; (b) cognitive difficulties worsen as the severity of HIV infection increases; and (c) the advent of clinically significant neurologic signs is associated with progression to more severe cognitive deficits. Our data suggest that the neurological and neuropsychological changes are both manifestations of the central effect of HIV on the CNS.

ISSN:0894-878X    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

SummaryThe extent to which individual discrete movements of Parkinson's disease (PD) patients could be facilitated by external cues was addressed in a simple sequential button-pressing task. A total of 16 PD patients and their individually age- and sex-matched controls participated. By systematically varying the placement of an auditory cue in each discrete movement of the sequence, the locus that best facilitated each person's performance could be determined. When the placement of the cue was individually tailored for each individual in the movement cycle, and a selected subset of such movements were individually cued, it was found to significantly facilitate sequential movement only for the PD patients and not the controls. However, the benefit accruing to PD patients from such selective cuing was far less than when all such movements in a sequence receive cuing, indicating the probable role of response set in Parkinsonian facilitation. A second experiment, this time involving 12 PD patients and their matched controls, examined the extent of dependence of PD patients' performance on external information. Although Parkinsonian performance was improved by the presence of advance visual information, as predicted, nevertheless the provision of irrelevantdelayedcues failed to disrupt performance. Although PD patients did not therefore appear stimulus bound, they may nevertheless depend extensively on external stimuli in performing sequential movements. It was concluded that problems in the smooth sequencing of movements is a major aspect of the movement deficit in PD, which could perhaps be attributed to loss of automatic internal cuing mechanisms from the dysfunctional basal ganglia.

ISSN:0894-878X    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

SummaryThe ability to organize, perform, monitor, and remember sequences of movements is typically ascribed to the frontal cortex. In this study, 13 Huntington's disease (HD) patients and 13 healthy control subjects (NC) were examined on a modified version of the Petrides and Milner self-ordered pointing task. HD patients made more errors in every task condition relative to NC subjects. However, task manipulations, including variations in list length, verbal versus nonverbal materials, and concrete versus abstract stimuli, affected HD patients in the same way as they did the NC subjects. Among the patients, disease severity correlated with performance in the most difficult condition only. The HD patients' impaired performance on this task is most likely attributable to disruption of frontal-subcortical circuits stemming from striatal neuronal loss.

ISSN:0894-878X    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

SummaryWe explored the inter-rater agreement and validity of diagnoses of Alzheimer's disease (AD) and other dementias made in an epidemiological study. A previously described protocol for cognitive screening and clinical assessment was applied to a large registry of twins. An expert panel then reviewed results from the assessment of 41 subjects whose screening results suggested the presence of AD. After review of the information at each of four stages of data collection, we assessed inter-rater agreement among the experts as well as their individual agreement with the final consensus diagnosis. We investigated these measures to assess the amount and quality, respectively, of new and diagnostically useful information that was revealed at each stage. A new scheme of weighted differences among the available diagnostic categories was developed for these analyses. As expected, incremental information from successive stages of data collection enabled the panel to increase their diagnostic agreement and rates of “correct” diagnoses. Over half of the total information was available, however, after review of only the initial telephone screening results (stage 1). A brief standardized videotape segment of the mental status and neurologic examinations provided substantial additional information. We were able to compare the final consensus diagnoses with autopsy results from seven individuals who had consensus clinical diagnoses of Probable or Possible AD (n = 6) or “demented, questionable etiology” (n = 1). All these subjects had Definite AD.

ISSN:0894-878X    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

SummaryThe “feeling of a presence” (FOP) refers to the illusion of being accompanied by an invisible being. The neurological mechanism underlying the illusion seems to be a projection of postural and kinaesthetic parts of the body scheme into extracorporal space. Its visual analogue is heautoscopy, i.e., thedoppelgängerexperience, and the FOP is, thus, best conceived as an awareness of one's invisibledoppelgänger.We present a tabular review of 27 published cases ofunilateralFOP after brain damage. We also report four new cases. Of the total 31 cases, in 19 (61%) the “presence” was lateralized to the right side of the body. Of the 12 cases with unilateral brain lesions, eight were in the left hemisphere and four in the right. It is concluded that the accepted notion of a general association between the FOP and right hemisphere dysfunction is incorrect. Prospective clinical studies will have to establish the reliability of the slight right hemispace bias we found for the appearance of the invisibledoppelgänger.Procedures known to elicit an illusory dislocation of the body scheme may further help to elucidate the neurological underpinnings of the FOP as well as of other forms of autoscopic reduplication.

ISSN:0894-878X    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

SummaryThe antiphospholipid antibody syndrome (APS) is defined by the presence of lupus anticoagulant or anticardiolipin antibodies and recurrent fetal losses, vascular thromboses, and thrombocytopenia. The recurrent vascular events may lead to stroke syndromes starting at a young age. Twenty APS patients, 14 with previous neurologic symptoms (APSWNS), six without neurologic symptoms (APSWONS), and 10 matched healthy volunteers, participated in the study. Evaluation included neurologic and psychiatric examination and the following neuropsychological tests: digit span, digit symbol (WAIS-R), logical memory (WMSR), eight-word list learning and recall, three words-three figure, trail A + B, Rey complex figure, and word-list generation. All patients underwent brain computed tomography (CT) or magnetic resonance imaging (MRI). Of the 14 APSWNS patients, 13 manifested hyperreflexia. Neurocognitive deficits included impaired attention, slowness, impaired semantic fluency, impaired memory, and impaired visuospatial functions. APS may be associated with neurocognitive dysfunction early in the course of the disease.

ISSN:0894-878X    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

SummaryWe studied long-term recovery from Ideomotor apraxia < 10 years after onset in 15 subjects with aphasia and apraxia. A detailed battery of praxis and language tests was administered twice: at a mean of 4.5 months after onset (T1) and at a mean of 81.6 months after onset (T2). Long-term recovery from apraxia — both limb apraxia (LA) and buccofacial apraxia (BFA)—was striking. However, differences were clear for recovery from LA and BFA. Long-term recovery from LA can be predicted by initial apraxia severity: the more severe the initial impairment, the less complete the long-term outcome. LA in fluent aphasics and nonfluent aphasics resolved equivalently. Recovery from BFA, in contrast, was more variable. BFA in nonfluent aphasics, although initially more severe than in fluent aphasics, resolved well in the long term, whereas recovery from BFA in fluent aphasics was poor. Recovery from LA and BFA demonstrated no significant correlation with recovery of language deficits. Aphasia and apraxia seem to have related but distinguishable recovery processes.

ISSN:0894-878X    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

SummaryThe records of 15 inpatients with a history of delusions or hallucinations after sustaining traumatic brain injury were procured from the archives of a state hospital. Studies of brain function and structure such as electroencephalogram (EEG), computerized EEG, single photon emission computerized tomography (SPECT), CT, and MRI were examined to investigate the relationship between lesion site and the presence of secondary psychosis. Although the majority of subjects had bilateral abnormalities on imaging studies, the modal lesion area was the right temporal area, followed closely by the left temporal and frontal areas. The majority of the patients also had a history of seizures and/or temporal lobe abnormalities on EEG studies. The results of our studies are generally consistent with those described in the literature.

ISSN:0894-878X    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

SummaryWe would like to describe two cases of treatment-resistant psychosis secondary to narcolepsy, successfully treated with stimulants. Narcolepsy may be confused with schizophrenia due to the hypnagogic hallucinations caused by REM intrusion into wakefulness. Narcolepsy should be considered as a possible diagnosis in patients with schizophrenia and a history of treatment-resistant psychosis.

ISSN:0894-878X    

出版商:OVID    

年代:1996

数据来源: OVID

ISSN:0894-878X    

出版商:OVID    

年代:1996

数据来源: OVID