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S Della Sala

Publications and source records attributed to S Della Sala.

At least 19 recordsLinked to original sources
PubMed1992

Recency, primacy, and memory: reappraising and standardising the serial position curve.

In this paper we consider the serial position curve in immediate verbal free recall. A large literature has argued that two components of the serial position curve, recency and primacy, reflect the functioning respectively of short-term and of long-term memory. However, there are a number of difficulties in interpreting the recency effect as a phenomenon uniquely associated with short-term memory. Moreover, the serial position curve has been used widely for clinical investigations in patients with memory deficits. This is despite the lack of norms for the measures derived from the curve. We present a set of standardised norms based on 321 Italian normal subjects. These norms are shown to be applicable both to an English speaking population, and to three groups of brain damaged-patients, namely Alzheimer's, amnesics, and frontals. The standardised norms offer a clinical and experimental tool which, coupled with a multiple single case approach, allows us to show dissociations and double dissociations among the performance patterns obtained from all three pathological groups. The paper concludes with a discussion of a possible interpretation of the recency effect as a emergent property of all types of memory system, including verbal short-term memory. Taking into account previous literature as well as our own data, the recency effect in immediate verbal free recall is here interpreted in terms of a two-component view of verbal short-term memory.

Adult↗
PubMed1992

A cancellation test: its reliability in assessing attentional deficits in Alzheimer's disease.

The aim of the study is to provide (i) a standardized procedure for a Cancellation Test of Digits, designed to assess in the visual modality selective attention deficits in patients with Alzheimer's disease, and (ii) a detailed analysis of how patients cope with it. Age-, education-, and sex-adjusted normative scores earned by 352 healthy controls are set forth, as well as data yielded by the Digit Cancellation Test in 74 Alzheimer patients, in 26 patients with a CT-assessed frontal lobe lesion and in a group of 24 healthy subjects urged to perform the task with a shortened time-constraint. Findings include discriminant power of Alzheimer patients versus healthy controls, sensitivity to cognitive evolution of the dementing process and analysis of errors. Attention data failed to supply psychometric support for the posterior-to-anterior algorithm of progressive cortical encroachment of Alzheimer's disease suggested by PET-findings. Emphasis is put on methodological aspects of neuropsychological research on Alzheimer patients and on the analysis of processing components of the tests employed. Results are discussed in the light of the relationships between psychometric assessments and related functions, and underlying neuronal degeneration.

Adult↗
PubMed1992

Does chronic lung failure lead to cognitive failure?

This study seeks to find out whether impaired cognition is associated with Chronic Obstructive Pulmonary Disease (COPD). Two experiments have been carried out to address two aspects of selective attention: a focused attention paradigm with a random and a facilitated condition and a divided attention paradigm with and without interference. Twenty-eight COPD patients and 28 matched healthy controls took part in both experiments. Reaction time (RT) was the variable considered. COPD patients had slower RTs than controls, however facilitation and interference had the same effect on both groups. No correlation was found between neuropsychological measures and lung failure indices. A threshold model in the lung-failure/brain-failure trade-off is envisaged.

Adult↗
PubMed1992

Neuropsychological evaluation of bleeding cirrhotic patients.

The cognitive profile was evaluated after an acute episode of esophageal bleeding in 26 patients with non-alcoholic hepatic cirrhosis and no previous history of acute hepatic encephalopathy. The neuropsychological test battery employed had been calibrated and standardized for age, sex, and education on a sample of 321 normal subjects. Cognitive deficits were found in some of the patients but it was not possible to selectively identify the tests that they failed or to establish a scale of severity for their scores. Further, there was no significant correlation between the psychometric and metabolic parameters. It would seem that the influence of chronic liver disease on brain functions builds up to a threshold effect, a hypothesis that calls for longitudinal studies.

Adult↗
PubMed1992

Efficacy of two temephos formulations against Chironomus salinarius (Diptera: Chironomidae) in the saltwater lagoon of Venice, Italy.

Two formulations of the organophosphorus insecticide, temephos (Abathion Granulare, 1% AI granular and Tambro Compresse, 2% AI tablet) were evaluated against Chironomus salinarius midge larvae in 50 x 50 m experimental plots in the saltwater lagoon of Venice, Italy. Each formulation was applied at 0.2 and 0.4 kg AI/ha. Abathion Granulare produced 56 to 73% larval reduction at 0.2 kg AI/ha and 69 to 83% reduction at 0.4 kg AI/ha during 3 wk after treatment. Abathion Granulare lost effectiveness at 4 wk after application at both rates. Posttreatment larval reductions resulting from Tambro Compresse applications ranged from 77 to 86% for 3 wk, and 82 to 92% for 4 wk at rates of 0.2 and 0.4 kg AI/ha, respectively. The tablet formulation (Tambro Compresse) gave better control of C. salinarius (magnitude and duration) than the granular formulation (Abathion Granulare) in these evaluations.

Animals↗
PubMed1991

Generative associative naming in dementia of Alzheimer's type.

Forty-eight patients with mild to moderate dementia of Alzheimer's type (DAT) were tested with a generative associative naming task, a task that combines the aspects of fluency and of word association tests. The variables taken into consideration were the number of adequate and inadequate responses, conventionality, word frequency and lexical-semantic relation to the target. DAT patients' performances were compared to those of a group of control subjects matched for sex, age and educational level. As a group, the patients gave fewer adequate responses, more idiosyncratic responses and perseverations, while there was no difference in the qualitative variables. However, the analyses of the performance profiles suggest that, irrespective of the severity of the disease, two major subgroups of DAT patients may be identified: (1) a first subgroup of subjects produced words with a lower conventionality rate and these were mostly in propositional relationship to the target; they also produced a higher rate of idiosyncratic responses and perseverations. (2) A second subgroup of subjects gave more conventional responses, mostly in the hierarchical-categorical relationship. The disorders of the former subgroup seem to correspond to a disrupted access to some relatively spared semantic abilities, whereas those of the latter to a semantic breakdown.

Aged↗
PubMed1991

Right-sided anarchic (alien) hand: a longitudinal study.

A patient with a bilateral frontal vascular lesion, encroaching upon the mesial cortex on the left and damage of the corpus callosum showed the 'alien hand' phenomenon on the right. The various hypotheses as to the nature of the lesion for the alien hand phenomenon to appear are discussed. It is proposed that an acute clinical condition, following a lesion of the corpus callosum only, should be differentiated from a chronic condition resulting from the additional fronto-mesial lesion.

Arm↗
PubMed1991

Case studies in working memory: a case for single cases?

Patterns of cognitive deficit in single neuropsychological cases are common sources of evidence for theories of normal cognition. In particular, the working memory model has benefited from data obtained from a number of contrasting patients, in some cases resulting in modifications of the working memory model. In this paper, patterns of data from short-term memory patients and anarthric patients are compared with patterns of data from normal subjects. The patterns of patient data that were unlike those patterns typically found for groups of normal subjects, could be incorporated within a modified version of the articulatory loop component of the working memory model. However a small number of individual normal subjects also did not show the pattern that is reported on the basis of average performance of groups of normal subjects. This causes some difficulty in interpreting those data from such 'aberrant normal' patterns, and those data from single patients with functional cognitive deficits. The implications of these findings for the interpretation of neuropsychological data are discussed in the context of the working memory model, but with the intention of making a general point pertaining to the development of functional models of cognition. It is argued that single case studies should continue to provide a useful source of evidence, providing that care is exercised in considering the implications of such data for models of normal cognition.

Adult↗
PubMed1991

The two-component hypothesis of memory deficit in Alzheimer's disease.

Becker (1988) has argued that Alzheimer's disease is particularly characterised by a combination of amnesic and dysexecutive deficits. He has supported this hypothesis by identifying patients who represent a relatively pure example of each of these. We describe a search for similarly pure patients in a sample of 55 carefully selected Alzheimer cases. We succeed in identifying one case each of relatively pure amnesia and relatively pure dysexecutive syndrome. We also, however, find cases of predominant STM deficit, as well as cases with defective visual but not verbal memory, and cases of the converse pattern. These cases do not seem to reflect simple random variation in the data, since less theoretically coherent patterns of symptoms are not found in this pure form. We conclude that AD can give rise to relatively specific cognitive deficits during its early stages, but that these do not necessarily argue for Becker's two-component interpretation of the cognitive deficit in Alzheimer's disease.

Aged↗
PubMed1991

The decline of working memory in Alzheimer's disease. A longitudinal study.

A previous study (Baddeley et al., 1986) explored the hypothesis that patients suffering from dementia of the Alzheimer type (AD) are particularly impaired in the functioning of the central executive component of working memory. It showed that, when patients are required to perform 2 concurrent tasks simultaneously, the AD patients are particularly impaired, even when level of performance on the individual tasks is equated with that of age-matched controls. Although the results were clear, interpretation was still complicated by 2 issues: first, the question of comparability of performance on the separate tests between AD and control patients; secondly, the question of whether our results could be interpreted simply in terms of a limited general processing capacity being more taxed by more difficult dual tasks than by the individual tasks performed alone. The present study followed up the AD and control patients after 6 and 12 mths. We were able to allow for the problem of comparability of performance by using patients as their own control. Under these conditions, there is a very clear tendency for dual task performance to deteriorate while single task performance is maintained. A second experiment varied difficulty within a single task in which patients and controls were required to categorize words as belonging to 1, 2 or 4 semantic categories. There was a clear effect of number of categories on performance and a systematic decline in performance over time. There was, however, no interaction between task difficulty as measured by number of alternatives and rate of deterioration, suggesting that the progressive deterioration in performance shown by AD patients is a function of whether single or dual task performance is required, and is not dependent on simple level of task difficulty. Implications for the analysis of the central executive component of working memory are discussed.

Aged↗
PubMed1991

Amyotrophic lateral sclerosis: a possible example of autosomal recessive inheritance.

A family is reported in which three out of four siblings of a consanguineous healthy couple developed adult onset Amyotrophic Lateral Sclerosis (ALS). All patients showed a similar clinical course with regard to disease progression and absence of cognitive deterioration. Laboratory findings included modification of Spinal Evoked Potential (SEP) and normal value of thiamine and thiamine monophosphate in cerebrospinal fluid (CSF). These data suggest an autosomal recessive mode of inheritance of ASL in this family.

Adult↗
PubMed1990

Post-traumatic extrapyramidal syndrome: case report.

We report the case of a young man with possible post-traumatic extrapyramidal syndrome. Some features of this case have a bearing on the controversy surrounding the existence of post-traumatic Parkinson disease.

Adolescent↗
PubMed1990

Controversial neuropsychological issues in Alzheimer's disease: influence of onset-age and hemispheric asymmetry of impairment.

A battery of 21 standardized neuropsychological tests was used in a retrospective study carried out on 52 mildly demented Alzheimer patients to analyse the relationship between age at onset of disease and the progress of cognitive impairment. Early onset was found to be associated with a more severe impairment. Possible sampling biases are discussed. Forty-seven patients were also tested for hemisphere asymmetry of cognitive impairment with two subsets of tests predominantly tapping left and right hemisphere abilities, respectively. We found a significant predominance of left-sided impairment which was not related to age at onset of disease. Possible relationship of this finding to healthy brain asymmetries is discussed.

Aged↗
PubMed1989

Selective visual attention in Alzheimer's and Parkinson's patients: memory- and data-driven control.

An automated visual search experiment was carried out on patients with incipient Alzheimer's disease, non-demented Parkinsonians and healthy controls to test for selective attention control within the framework of the Norman and Bobrow (1975) model. The performances of the Parkinsonians and healthy controls were consistent with the predictions of this model but those of the Alzheimer patients were not. These patients appeared to be no longer sensitive to the facilitation supplied by the stimulus context and to spend most of their residual resources on achieving accuracy. The reduction of their attentional resources possibly interferes with the control of the speed-accuracy trade-off.

Aged↗
PubMed1989

Autobiographical memory. Its impairment in amnesic syndromes.

Three groups of brain-damaged patients with severe anterograde episodic amnesia, manifest both ecologically and psychometrically, were tested with an autobiographical memory (ABM) inquiry for which age-education adjusted normal baselines were available. One group was made up of 19 patients in the early stages of Alzheimer's disease and the other of 12 "pure" amnesic patients, 6 of whom had focal diencephalic damage and 6 widespread brain damage. ABM information retrieval was severely impaired in 84% of the early-stage demented patients and in the "pure amnesics" with widespread brain damage, but much less in those with focal damage. No temporal gradient emerged in either group and confabulation was only a marginal factor. Poor performances of demented and nonfocal amnesics were attributed to inertness in the search process.

Alzheimer Disease↗
PubMed1989

Autobiographical memory. Sensitivity to age and education of a standardized enquiry.

A structured enquiry for assessing autobiographical memory is proposed. It is made up of three standardized time-cued sets of questions focusing on three life periods: adolescence, early and late adulthood, with five questions for each life period. Standardized testing procedure, checking for veracity and scoring methods are described. Normative data from 157 healthy individuals aged over 55 are converted into 'equivalent scores' for use with the enquiry and for diagnostic purposes. Education and ageing, but not sex, appear to be significant factors in the efficiency of retrieval from the autobiographic repertoire.

Aged↗