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E Sieroff

Publications and source records attributed to E Sieroff.

5 recordsLinked to original sources

Right spatial neglect after left hemisphere stroke: qualitative and quantitative study.

OBJECTIVES: Comparatively little research has been conducted on right neglect after left brain damage. The authors sought to assess contralateral neglect in subacute left hemisphere stroke patients using a comprehensive test battery validated in a large control group after right hemisphere stroke. METHODS: Seventy-eight left hemisphere stroke patients were assessed. The test battery included a preliminary assessment of anosognosia and visual extinction, a clinical assessment of gaze orientation and personal neglect, and paper-and-pencil tests of spatial neglect in the peripersonal space. Only nonverbal tests were used. RESULTS: Drawing and cancellation tasks revealed neglect in 10 to 13% of patients. The combined battery was more sensitive than any single test alone. A total of 43.5% of patients showed some degree of neglect on at least one measure. Anatomic analyses showed that neglect was more common and severe when the posterior association cortex was damaged. CONCLUSIONS: The frequency of occurrence of right neglect was, as expected, much lower than that reported in a study using the same assessment battery in right brain damage stroke patients. Nevertheless, neglect was found in a substantial proportion of patients at a subacute stage, suggesting that it should be considered in the rehabilitation planning of left brain damage stroke patients.

Awareness↗

[Presenting a battery for assessing spatial neglect. Norms and effects of age, educational level, sex, hand and laterality].

The aim of this study was to build up a battery for assessing spatial neglect, then to analyse the norms and potential effects of age, education level, sex, hand used, and laterality. It was also to contribute evaluating the pseudoneglect phenomenon described by Heilman, which consists in a tendency of normal subjects to neglect the right peripersonal space. Tasks selected were presented to important groups of normal subjects, most often larger than 450. The battery comprised of a bell cancellation test, scene copy, clock drawing, two line bisection tasks, identification of overlapping figures, text reading, writing task, and the representational task of the France map. For each of them, different variables were selected, especially investigating the difference between performance in the right and the left hemispaces. This study allowed defining the threshold values (percentiles 5 and 95) for deciding of the pathological character of a patient performance. It also showed that the pseudoneglect phenomenon is more obvious in some tasks such as line bisection, and probably also in the representational task of the France map and writing. His importance and at times his side were influenced by the factors we studied, with between tasks differences, but also by the nature of the task to be performed, and especially his verbal component.

Adult↗

Preparatory attention: experiment and theory.

This study investigated attention to a spatial location using a new spatial preparation task. Participants responded to a target dot presented in the center of a display and ignored a distractor dot presented to the right or left of the center. In an attempt to vary the level of preparatory attention directed to the target, the distractor dot was presented prior to the onset time of the target and the relative frequency of distractor dots to target dots within a block of trials was varied. The results from the first three experiments showed that when instructions induce weak preparatory attention to the target location, response times to a target on target-only trials increase substantially as the percentage of trials containing a distractor increases from 0 to 75%. In Experiments 2 and 3, instructions and display saliency were used to induce strong preparatory attention to the target location, resulting in almost constant response times across distractor percentages. Experiment 4 varied percentage of target trials in the absence of distractors, with the result that response times decreased as target trial percentage increased. Accounts of these data by early "activity-based" and late "criterion-based" attention theories are compared, and the early theory is given a more detailed description within the context of a cognitive neuroscience theory of attention.

Adolescent↗

[Writing disorder using a word processor: role of the left hand].

A young female secretary developed a writing disorder, exclusively expressed when using a word processor, following an ischemic vascular event involving the insula and the right posterior parietal region. There was no disturbance of laterality. The neurological examination, completed by neuropsychological tests eliminated any persistent phasic or gnostic disorders. The analysis of the text produced revealed abnormalities leading to the conclusion that the left hand was responsible for all the errors observed. A sensorimotor integration disorder produced a melokinetic apraxia which appeared to be the cause of the writing disorder which would have most likely remained unknown had the subject not been a secretary.

Adult↗