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Children with SLI use argument structure cues to learn verbs.

Across two tasks, children's use of argument structure cues to learn verbs was tested. In Task 1, we examined children's use of cues to interpret novel verbs while viewing single action scenes. In Task 2, we examined the role of cues for novel verb interpretation and retention through a story viewing task. The participants were 20 6-year-olds who were diagnosed as specifically language impaired (SLI) and 40 normally developing children who served as either age-matched or language-matched controls. Across tasks, the children with SLI demonstrated an ability to use cues to interpret verb meaning. For Task 1, scores of the children with SLI were not significantly different from those of either control group; for Task 2, their scores exceeded chance and were not found to be different from those obtained by the language-matched controls. When verb retention was examined, scores of the children with SLI were lower than those of both control groups, and they also did not exceed chance even after repeated exposure to the stimuli and additional testing. Patterns within the data ruled out inattention and an inability to follow the narrative as contributing to the children's low scores. Additionally, poor verb retention was not found to be related to a limitation in the perception and encoding of the cue content. Specific deficits with the storage and retrieval of grammatical information within the lexicon, general working memory/capacity limitations, or both are posited as plausible, but unconfirmed, explanations for the verb retention difficulties of the children with SLI.

Child↗

Subjective cognitive dysfunction in first-episode and chronic schizophrenic patients.

Previous studies indicate that first-episode and chronic schizophrenic patients do not differ regarding neuropsychological performance as assessed with standard cognitive tasks. For the present study, it was investigated whether first-episode and chronic schizophrenics report similar subjective cognitive deficits. The Frankfurt Complaint Questionnaire (FCQ), a scale devised for assessing subjective cognitive disturbances in schizophrenia, was administered to 20 first-episode and 36 chronic schizophrenic patients, as well as 20 healthy controls. The schizophrenic subsamples did not differ on any of the FCQ subscales or on a "lie scale," measuring illness denial. Psychopathological ratings were comparable for both groups. As expected, healthy subjects reported significantly less cognitive and perceptual problems than schizophrenic patients. In marked contrast to a Kraepelinian view of schizophrenia, the present data confirm previous studies conducted with objective neuropsychological tests that schizophrenia is a neurodevelopmental rather than a neurodegenerative disorder.

Adult↗

The nature of the naming deficit in Alzheimer's and Huntington's disease.

A comparison of naming performance, on the Boston Naming Test, of 52 patients with dementia of Alzheimer's type (DAT), 16 patients with Huntington's disease (HD) and 52 normal control subjects was performed using a comprehensive classification of error types. Spontaneous and cued naming scores were significantly impaired both in the DAT and HD groups, but performance in the DAT patients was significantly worse than that of the HD patients. Normal controls made predominantly semantic-category and circumlocutory errors. The HD group differed from normal only in the proportion of visually based errors, which was greater in the patient group. By contrast, the DAT patients made a significantly greater proportion of semantic-superordinate and semantic-associative errors. The same pattern of naming errors was found when a group of DAT and HD patients matched for overall naming ability was compared. A subgroup of 22 DAT patients was followed longitudinally over 3 y. Their deterioration in overall naming performance was accompanied by a consistent change in the profile of naming errors: the proportion of semantic-associative errors increased significantly as did the proportion of visual errors. These results are considered in the light of current cognitive models of naming. They suggest that in HD, naming deficits initially involve disruption of perceptual analysis, whereas in DAT such impairments in the early stages reflect a breakdown in semantic processes. However, as DAT progresses, perceptual problems also begin to contribute to the patients' naming difficulties. Postlexical (phonemic) processes remain relatively intact throughout in both diseases.

Aged↗

Cognitive rehabilitation for schizophrenia: is it possible? Is it necessary?

Limitations of available psychosocial interventions combined with the increasing evidence that schizophrenia is characterized by diverse deficits in information processing has stimulated great interest in the possibility of cognitive rehabilitation. However, the current optimism seems unjustified. The precise role of information processing in the behavioral handicaps evidenced by schizophrenic patients is not clear, and the neuropsychologic and experimental psychopathology tasks used to assess information processing generally cannot specify precisely which cognitive functions are deficient. Thus, the choice of cognitive targets for rehabilitation is arbitrary. The strategies currently employed for rehabilitation emphasize an exercise model of treatment and the use of complex mnemonics. Neither approach has been successful in rehabilitating brain-injured patients, and preliminary results with schizophrenic patients are not very promising. It is concluded that the field might be better served by focusing on environmental change and compensatory strategies until we determine how and why schizophrenic patients fail.

Behavior Therapy↗

Category fluency is also predominantly affected in Swiss Alzheimer's disease patients.

OBJECTIVES: To establish the comparative efficacy to differentiate between Swiss patients with dementia of the Alzheimer type (DAT) and elderly normal control subjects (NC) on two different verbal fluency tasks: category fluency and letter fluency. MATERIAL AND METHODS: Fifty Swiss German DAT patients in the early stages of the disease and 50 matched normal control subjects were compared on letter and category fluency tasks. RESULTS: DAT patients exhibited an overproportional impairment on category fluency as compared with letter fluency. Receiver operating characteristic curves (ROC) showed that category fluency correctly classified a significantly higher number of DAT patients and NC subjects (84%) than letter fluency (70%). CONCLUSION: As similar findings have been described for English-speaking DAT patients, we conclude that deficiencies in category fluency are a general phenomenon, reflecting impaired structures of semantic knowledge occurring early in the course of Alzheimer's disease.

Aged↗

The clinical syndrome of Alzheimer's disease: aspects particularly relevant to clinical trials.

This paper describes the natural history of the clinical syndrome of Alzheimer's disease (AD) including the cognitive deficit, the neuropsychiatric symptoms, impact on daily functioning, risk factors, medical complications and impact on the use of health-care resources. The clinical presentation of the disease varies greatly from the prodrome through end stage; instruments used to quantify the severity of each aspect of the disease have been developed and are described along with their use in clinical drug trials. Drug treatments for AD are usually developed by first showing a positive effect on the cognitive deficit, with later studies investigating drug effects on other clinical aspects of the disease.

Alzheimer Disease↗

Increased middle cerebral artery flow velocity during the initial phase of cardiopulmonary bypass may cause neurological dysfunction.

One hundred twenty-seven patients undergoing coronary artery bypass graft surgery were monitored by transcranial Doppler ultrasonography. Five patients had more than 50% increases in middle cerebral artery mean flow velocity during the initial phase (10-120 sec) of cardiopulmonary bypass. Four of these 5 developed neurological complications including stroke and encephalopathy. These results indicate that overperfusion of the basal cerebral arteries during cardiopulmonary bypass procedures may contribute to neurological dysfunction after the surgery.

Adult↗

Testing a computational account of category-specific deficits.

Patients displaying mild symptoms of Alzheimer's disease sometimes have more difficulty naming items from an artifact than from a natural kind category; others displaying more severe symptoms almost always have more difficulty naming items from a natural kind than from an artifact category. This paper examined a computational model of this double dissociation (Devlin, Gonnerman, Andersen, & Seidenberg, 1998). Four basic tests of the model were proposed: The model should be able to generalize to new exemplars, the model should be expandable such that training sets of a realistic size can be used, the model's performance should not be unduly affected by small changes in architecture, and the learning algorithm should produce results that are not inconsistent with any major underlying factor of semantic organization. The model was found to be deficient in all four areas. Results reported from the model may therefore have been idiosyncratic to the model and not reflect general properties of a real semantic system.

Algorithms↗