The influence of gaze behaviour on postural control from early childhood into adulthood

In the present study we aimed to track the influence of natural gaze behaviour on postural control from early childhood into adulthood. We measured time series of centre of pressure (COP) as well as head movement in three children groups aged around five (n = 16), eight (n = 15), and eleven (n = 14) and in one group of young adults (n = 15) during quiet stance with eyes closed, gaze fixed on a dot, and with gaze shifts between two dots. We adopted magnitude and irregularity of COP displacement as indexes of postural control and cross correlation between COP displacement and target oscillation as an index of the dynamical coupling between the postural and visual systems. Magnitude and irregularity of COP displacement decreased with age, which suggests a steady improvement of postural control from five to beyond eleven years of age. Cross correlations were weak and relative phases highly variable across age groups. Across conditions, and most prominently in the gaze shift conditions, 5-year-olds showed both more head movement and lower postural stability than other age groups. Finally, only in 5-year-olds did we find a marked deterioration of postural stability with gaze shifts. We thus conclude that excessive head movement, particularly during gaze shifts, may be a primary cause of lower postural stability in young children compared to older children and adults.

► Magnitude and irregularity of centre-of-pressure displacement decreased with increasing age from early childhood into adulthood. ► Magnitude of head movement during a stationary gaze and during gaze shifts decreased with increasing age from early childhood into adulthood. ► In 5-year-olds a marked deterioration of postural stability with gaze shifts. ► Gaze shifts had no influence on postural stability in 8-year-olds, 11-year-olds and young adults. ► Weak coupling between COP displacement and target oscillation and highly variable relative phases across age groups.