Handedness and differences of verbal and spacial orientation skills among children in terms of their laterality
Abstract
This study focuses on the phenomen of handedness and possible differences of verbal skills and spatial orientation abilities among left-handers and right-handers. Such differences may be caused by discrepancies in the distribution of specialized functional areas in the brain hemispheres among these two groups or environmental factors.
Differences between left-handers and right-handeres have been explored in a series of studies but the findings remain inconclusive. In this study I focus on a group of elementary school students at the age of 10 to 11 years.
Students were classified as left or right-handers after performing ten common manual tasks. Language-analytical and spatial orientation tests were administrated in a paper form, verbal fluency was tested orally.
Statistical calculation carried out through multivariate analyses of variance revealed that age has significant influence on the results of the tested students. The effect of sex was found only at the verbal fluency task, where the girls outperformed the boys.
The effect of handedness was found also only at the verbal fluency task, where the right-handers outperformed the left-handers. In both of the latter mentioned cases the findings were not identified as significant.
Possible fluctuating influence of sex among left and right-handers wasn't found nor the fluctuating influence of the handedness among girls and boys. Small effect size was calculated for all of the results.
These findings are showing large interindividual differencies and ongoing developement among this old children in both verbal and spatial orientation skills. Also they're showing possibility of relationship between left-handedness and onerous ability of articulation as a motoric ability that may be caused by the discrepancies in distribution of specialized functional areas in the brain hemispheres.