Subjective visual vertical and postural performance in healthy children.
BACKGROUND
Verticality is essential in our life, especially for postural stability. Subjective vertical as well as postural stability depends on different sensorial information: visual, vestibular and somesthesic. They help to build the spatial referentials and create a central representation of verticality. Children are more visuo-dependant than adults; however, we did not find any study focusing on how children develop their sense of verticality.


METHODS
WE STUDIED TWO GROUPS OF SUBJECTS: 10 children (from 6 to 8 years) and 12 young adults. We recorded postural stability with a Techno Concept plateform and perception of subjective visual vertical in the following conditions: while adjusting the vertical in the dark or with visual perturbation, while fixating the vertical bar, and with eyes closed.


RESULTS
Children are more instable than adults in terms of postural parameters, and also while performing a double task, especially when no visual references are present. They also present a higher variability and lower accuracy than adults in reporting their perception of true vertical reference.


CONCLUSIONS
Children might have limited attentional resources, and focus their attention on the more demanding task, corresponding to the U-shaped non-linear model.
Université Pierre et Marie Curie, Paris, France ; Children balance Evaluation Center, Robert Debré Paediatric Hospital, Paris, France.
Chrystal
C
Gaertner
Maria Pia
MP
Bucci
Rima
R
Obeid
Sylvette
S
Wiener-Vacher
D000328:Adult; D000704:Analysis of Variance; D002648:Child; D006801:Humans; D011187:Posture; D013028:Space Perception / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult