Introduction: This work is a part of the population studies conducted among deaf children and adolescents, aged 7 - 19, in Poland under the government’s grant. The aim of this study was to determine the level and trends of the somatic and motor skills development changes. The body lateralization was one of the diagnosed parameters.
Material and methods: The research was conducted in 24 centers for deaf children localized on the Polish territory. A total of 1194 subjects were examined including 482 girls and 712 boys. In the group of subjects aged 14 to 16 was 415 people including 161 girls and 254 boys. The lateralization evaluation was made using the Wroclaw Asymmetry test. The direction and the profile of functional asymmetry in the examined age groups were determined; the assessment of the change trends and the dimorphic diversity in the 14 to 16 years of age group was carried out.
Results: Analysis of obtained results showed that the level of lateralization in the deaf, aged 14 to 16 years, is high and similar to the trends known from the ontogenesis in normal hearing subjects. An eye was the higher oriented organ and a lower limb - the lower. The right handiness was most often observed as to the handiness. The dominant profile was the determined uniform one. Both the direction and the profile are making significantly differentiating girls from boys. In the age between 14 and 16 years of age the body lateralization changes occur and they are especially visible in organs characterized by the low lateralization.
Conclusions: Lateralization is an important process in human development, because its established level determines the proper action. Children with impaired lateralization often have learning difficulties, both intellectual and motor. Diagnosing the level of lateralization is therefore an important area for educational activities that could help to stimulate the process of lateralization and thus to prevent developmental abnormalities in pupils.
Financed by the National Centre for Research and Development under grant No. SP/I/1/77065/10 by the strategic scientific research and experimental development program:
SYNAT - “Interdisciplinary System for Interactive Scientific and Scientific-Technical Information”.