FREQUENCY-CHARACTERISTICS OF POSTURAL CONTROL OF CHILDREN WITH AND WITHOUT VISUAL IMPAIRMENT

During quiet standing on a force platform, centre of pressure frequenc y characteristics of normal and visually impaired children were invest igated under four conditions: normal surface, eyes open and closed; fo am surface, eyes open and closed. Total power was calculated between 0 and 4Hz. Slopes of logarithmically transformed data were used to comp are relative power at high and low frequencies. Younger children had g reater total power and relatively more high frequency power. The resul ts suggest that young children (four to six years) do not normally use immediate vision in postural control. Visually impaired children have greater instability than sighted children, with greatest differences between the two groups at 10 to 12 years.