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Biomedical subjects

J B Davidoff

Publications and source records attributed to J B Davidoff.

7 recordsLinked to original sources

A dyscalculic patient with selectively impaired processing of the numbers 7, 9, and 0.

A patient (J.C) had particular difficulties with the numbers 7, 9, and 0 in aurally and visually presented calculations. These problems were explained in terms of a modified version of the McCloskey, Caramazza, & Basili (1985) model of calculation processes. His calculation difficulties were attributed to degraded semantic representations of the numbers 7 and 9 and to lost knowledge of rules governing calculations involving the number 0. Use of "noncalculation" number processing tasks confirmed that his 7/9 problem was not at the level of acoustic analysis, the auditory input lexicon, the phonological output lexicon, visual analysis, or the orthographic output lexicon.

Brain Injuries

Some effects of color on naming and recognition of objects.

In this article, we investigated the role of color in the recognition and naming of everyday objects. In the first experiment we found that color pictures were named faster than black-and-white and that shape information did not facilitate color naming. Experiment 2 was carried out to determine at which stage of object processing the color facilitation occurred. We found that color had no effect on object recognition but did facilitate object naming, even when color was redundant for discrimination. This did not apply to naming abstract shapes. Experiment 3 replicated the findings of Experiment 2 using different objects and colors. The results showed that color could facilitate but not inhibit object naming and did not affect object recognition.

Adolescent

Hemispheric differences in dot detection.

Two experiments are reported using normal subjects which show a superior detection for dots in the left visual field. This is shown to be more pronounced for stimuli of reduced contrast and for male subjects. The cerebral activation hypothesis of hemispheric asymmetries is tested and found to contribute towards a visual field advantage to some extent but a structural account is also suggested. It is considered that the right hemisphere is prepotent for dealing with simple perceptual stimuli even when there is no spatial component for the task.

Adult