Dynamical analysis of the interaction between object location and hand use in a midline crossing task in children with trisomy 21

• Autor(a) principal: Catela, David
• Data de Publicação: 2018
• Outros Autores: Abreu, Ana, Seabra, Ana Paula
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.15/4760
• topic: prehension; laterality; trisomy 21; spatial constraints; hysteresis; midline crossing

Objective: The aim of the study was to analyze the influence of spatial constraints on the hand use in children with trisomy 21. Methods: Participants were 31 children with trisomy (13.35 ± 2.78 years old, 18 girls) (T21) and 38 children with typical development (8.62±.79 years old, 22 girls) (TD), with similar APGAR scores at birth (1 mn and 5 mn), but with significantly different mental age in Goodenough test. Children grasped seven colored Styrofoam balls in a semi-circumference arraying; in a pseudorandom condition (R) and in a scaling condition (increasing sequence [IS]- from left to right hemispace; decreasing sequence [DS]- from right to left hemispace). Results: In the R, TD displayed a significantly greater frequency of midline crossing than T21, as in the DS; but not in the IS condition. T21 showed significantly larger hysteresis in the left hemispace, as well as in the midline location, but not in the right hemispace. In R, IS and DS, no significant differences were observed between TD and T21 in the frequency of left-hand use. Conclusion: Spatial constraints highly determined T21 hand-use, as clearly expressed in the pattern of midline crossing and of hysteresis. In T21, the scaling procedure permitted the detection of patterns of interaction among spatial and intrinsic constraints, that the traditional R procedure would not. This perceptual-motor pattern of behavior should be considered as criteria in the planning of perceptual-motor intervention for children with T21. We propose the “task constraints attunement hypothesis”, suggesting that T21 children (and, probably others with developmental problems) reveal more left-handedness and less asymmetry because they are compelled to use the hand in accordance with spatial constraints.