Biomedical subjects

P Prosperini

Publications and source records attributed to P Prosperini.

9 recordsLinked to original sources

PubMed2001

Educational level and age influence spatial working memory and Wisconsin Card Sorting Test performance differently: a controlled study in schizophrenic patients.

The influence of educational level and age on executive function, as evaluated by the Wisconsin Card Sorting Test (WCST), and 'working memory,' as evaluated by means of a visual-manual delayed-response task, has been investigated in 25 schizophrenic patients and 35 healthy controls matched for age. Different patterns of correlations between educational level, age and cognitive variables were seen for the 'working memory' task but not for the WCST. No significant correlations between the WCST and the 'working memory' task indexes have been observed. Based on multivariate analyses, poor performance of schizophrenic patients on working memory and executive function tasks was observed; after covarying for the educational level, group differences were no longer significant for executive functions, but the difference in 'working memory' performance persisted. The implications of sociodemographic variables as well as the role of statistical manipulation are evaluated and their differential impact on 'working memory' and executive functions is proposed in further support of these neurocognitive constructs that may be dissociable.

Adolescent↗

PubMed2000

Processing of context information in schizophrenia: relation to clinical symptoms and WCST performance.

Failure in contextual information processing has been hypothesized as being the single function responsible for several impairments in cognitive tasks and symptoms, through an involvement of the prefrontal cortex, in patients with schizophrenia. A variant of the Continuous Performance Test (CPT) designed specifically to elicit deficits in the processing of contextual information has been administered to 20 schizophrenic patients and 20 healthy controls. The relation to Wisconsin Card Sorting Test (WCST), relatively specific to prefrontal damage and executive dysfunctioning, and clinical status by using scales for the assessment of positive, negative symptoms and outcome has been investigated. The data show that multi-episode schizophrenic patients manifest inability to use contextual information to inhibit habitual response to an ambiguous stimulus and to maintain information across delay, without a general attention deficit. We also found a relationship between contextual reasoning and WCST unique errors, hallucinations, formal thought disorders, and outcome evaluation. Our results further support the hypothesis that the deficit of contextual reasoning could account for cognitive impairments and symptoms of patients with schizophrenia.

Adult↗

PubMed2000

Awareness of illness and outcome in schizophrenia.

The purpose of the present study was to investigate whether awareness of illness affects specific measures of outcome in schizophrenia. Patient awareness was evaluated using a shortened version of the Scale to Assess Unawareness of Mental Disorder (SUMD). Patient outcome was assessed by means of the Strauss-Carpenter scale. Our findings indicate that lack of awareness of "negative symptoms" has a considerable impact on outcome: in fact "Social Contacts" highly correlated with Blunt Affect, Anhedonia and Asociality items on the SUMD. Lack of awareness seems then to be a powerful predictor of poor outcome.

Adult↗

PubMed2000

Neuromorphological abnormalities in schizophrenic patients with good and poor outcome.

OBJECTIVE: The present study was designed specifically to assess the relationship between brain morphology and outcome in schizophrenia. METHOD: Fifty-six schizophrenic patients and a matched group of 32 healthy subjects were studied with magnetic resonance (MR) imaging scans. Clinical assessment included the Krawiecka-Manchester Scale (K-MS) and the Outcome scale by Strauss and Carpenter. RESULTS: Along several neuromorphological measures the patients differed from controls only for right and left ventricular volumes. The 'poor outcome' patients had a left and right ventricular enlargement when compared to the 'good outcome' patients and healthy controls. A regression analysis showed that right ventricle volume, left temporal lobe volume and left hippocampal volume entered into the regression equation, accounting for a 27% of the outcome measure. CONCLUSION: The outcome does not seem to be predicted by one particular morphological site but involves different brain regions; however, the ventricular enlargement identifies a subgroup of patients with poor outcome.

Adult↗

PubMed2000

The cognitive bias task (CBT) in healthy controls: a replication study.

Contextual processing is the selection and bringing "on-line" of internal representations of a task that can be used in planning and mediating goal-appropriate behavioral responses and is a relevant issue that probably is involved in many neurological and psychiatric conditions. The Cognitive Bias Task is a measure of context-dependent responding, is sensitive to quadrant-lesion effects, and interacts with gender. The goal of this study was to replicate and detail more completely the method of context-dependent processing for healthy control patients on the Cognitive Bias Task. The results show the presence of three different cognitive patterns that could biases the response of control patients: context-independent, context-dependent, and mixed. Gender, but not handedness, significantly influences contextual processing, with more females than males producing a context-independent pattern of responding. Test results and the relation of contextual processing in psychiatric disorders were discussed.

Adult↗

PubMed1999

Spatial working memory assessment by a visual-manual delayed response task: a controlled study in schizophrenia.

'Working memory' dysfunction has been proposed as a central cognitive feature in schizophrenia. To further explore this issue we developed a computerized easy and fast to administer test using the standard keyboard as visual-manual subject-computer interface along a delayed-response paradigm. The test has been administered to 25 patients who met the DSM-III-R criteria for schizophrenia and 25 healthy control subjects matched as possible for sex. The data confirm the visuo-spatial 'working memory' dysfunction in schizophrenic patients. The test maintains the discriminative capacity of similar previously devised tasks with the advantages of being usable on almost every standard computer and shorter and more acceptable for severely disabled patients also. The test can be considered an useful tool to study the 'working memory' impairment in the cognitive deficit of schizophrenia.

Adult↗

PubMed1997

Is Wisconsin Card Sorting Test performance related to 'working memory' capacity?

The Wisconsin Card Sorting Test (WCST) is a multifactorial and complex test, and it involves so many different kinds of functions that it is difficult to understand why patients fail. Capacity of 'working memory' is possibly involved in the WCST performance and is considered a relevant factor responsible for the schizophrenics' poor performance. The present study was specifically designed to assess the relationship between 'working memory' measurements and WCST performances of schizophrenics. Furthermore, we investigated the relationship between the cognitive dysfunction and the clinical symptomatology. The following tests were administered to 30 schizophrenics and 25 healthy subjects: WCST, Digit Span Test (Backward and Forward), Digit Symbol Substitution Test and Visuo-Spatial 'working memory' Test, a card test appropriately devised. Clinical assessment included the Italian version of the scale of Krawiecka Manchester Scale (K-MS) and the Outcome scale by Strauss and Carpenter (1972). The 30 patients differed significantly in all the neuropsychological variables from the controls. WCST indexes did not correlate significantly with any of the 'working memory' measures (visuo-spatial and verbal) in the samples studied. No relationship was seen between the neuropsychological performances and clinical symptomatology as evaluated by the K-MS scale. WCST indexes and DSST significantly correlated with the outcome measure. The results do not support the hypothesis that executive dysfunction as evaluated by WCST is attributed to 'working memory' impairment, rather they could suggest that these two neuropsychological functions identify different neurocognitive constructs.

Adult↗

PubMedDate not supplied

Cognitive function in euthymic bipolar patients, stabilized schizophrenic patients, and healthy controls.

Studies on cognitive function in bipolar disorder have led to contrasting results and few data are available on affected subjects during the euthymic phase. In the present study we investigated the cognitive function of a cohort of bipolar (n=40) and schizophrenic (n=66) patients compared to healthy controls (n=64). Patients were evaluated in the outpatient setting over at least 3 months using a computerized version of Wisconsin Card Sorting Test. Schizophrenic patients showed the worst performance while that of the bipolar patients was somewhere between schizophrenic and controls. A discriminant analysis was able to classify correctly 60.59% of the subjects (schizophrenics 48.5%, bipolars 40%; healthy controls 85. 9%). The scores of the Wisconsin Card Sorting Test were entered into a principal component analysis, which yielded a 2-factor solution. Even in that analysis bipolar patients showed intermediate features in comparison with the other groups. These data indicate that bipolar patients have subtle neurocognitive deficits even after the resolution of an affective disorder. As well as observing quantitative differences between groups, the results show different dimensions of cognitive performance within groups suggesting that the deficit of euthymic bipolars could be a dishomogeneous entity, probably more heterogeneous than that in schizophrenia. Studies administering a more complete neuropsychological battery could further clarify the nature and meaning of the cognitive deficits in schizophrenia and bipolar disorder.

Adult↗

PubMedDate not supplied

Tower of Hanoi and WCST performance in schizophrenia: problem-solving capacity and clinical correlates.

We administered a computerized version of WCST, a well established test, sensitive to executive function deficits in schizophrenia that involves many features of cognitive processing, and of Tower of Hanoi, a test that may offer cognitive challenges more specifically related to planning and sequencing, to 28 schizophrenic patients and 28 matched controls to examine a worthwhile question regarding the relative ability of these two tasks to differentiate schizophrenia and normal groups as well as exploring the relationship of these two instruments to clinical variables. The schizophrenic patients performed significantly worse than normal subjects both on Tower of Hanoi test and on WCST. The discriminant analysis identified in a multivariate way a pattern of indexes that differentiate the two groups. This pattern, characterized by specific indexes of WCST and TOH, could suggest the existence of a common underlying factor that determines the cognitive impairment in problem-solving of schizophrenics. These findings and the relationship with positive and negative symptoms have been discussed in the light of the model of the impairment in the internal representation of context information.

Adult↗