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C Umiltà

Publications and source records attributed to C Umiltà.

At least 91 records · Page 5Linked to original sources

Evidence for a right hemisphere superiority and for a serial search strategy in a dot detection task.

In Experiment I the subjects manually signaled whether a solid dot was present or not in an array of empty dots presented either in the right or in the left visual field. The dots were either three or six and the target could appear in any of the possible locations. The results showed (a) a left visual field superiority; (b) a left hand superiority; (c) faster responses to three-dot than to six-dot displays, and (d) an effect of the location of the target in the display. Experiment II exactly replicated the previous experiment with the exception that the stimuli were centrally projected. The results showed: (a) a left hand superiority; (b) an effect of the number of dots in the display. These results can be interpreted to indicate: (a) a right hemisphere specialization in a simple feature detection task without any spatial component; (b) the compatibility of a right-hemisphere advantage with a serial search strategy.

Adult↗

Hemisphere-dependent cognitive performances in epileptic patients.

Short-term memory (STM), long-term memory (LTM), and recency judgment were investigated in 75 right-handed nonaphasic patients without visual deficits who had epileptic foci localized in one of four different regions of the brain: right temporal lobe, left temporal lobe, right frontal lobe, and left frontal lobe. The results led to the following conclusions: (1) left temporal lesions yielded comparatively greater impairment for the verbal LTM task, whereas right temporal lesions were more disruptive for the spatial LTM task; (2) no significant differences between left- and right-brain-damaged patients in STM tasks were obtained; (3) left frontal lesions yielded deficits in a recency task in accordance with hemispheric specialization; (4) only prolonged epileptic syndromes impaired neuropsychological performance in those tests; (5) comparisons between male and female patients and between those with and without clear evidence of a structural lesion did not reach statistical significance.

Adolescent↗

Different levels in processing simple geometrical figures.

An experiment has been conducted in order to extend to geometrical figures Posner's (1969) findings of various levels of processing for alphabetical material. Pairs of simple figures (triangles and trapezoids) were tachistoscopically presented to subjects asked to judge if they were "same" or "different". Subjects were instructed to respond "same" either if the two figures had the same shape or the same name, e.g., a scalene triangle paired with a right-angled one. The results support the theory of different levels of processing also for geometrical figures.

Adult↗