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Updated: Jul 16, 2026
Assessment of Static Graviceptive Perception in the Roll-Plane using the Subjective Visual Vertical Paradigm
Published on: April 28, 2020
Is backward disequilibrium in the elderly caused by an abnormal perception of verticality? A pilot study
Patrick Manckoundia1, France Mourey, Pierre Pfitzenmeyer
1INSERM/ERIT-M 0207 Motricité-Plasticité, Université de Bourgogne, Dijon, France. patrick.manckoundia@chu-dijon.fr
Objective:
We hypothesised that backward disequilibrium (BD), defined by a posterior position of the centre of mass with respect to the base of support, could be caused by a backward tilt in the perception of verticality.
Methods:
The relationship between BD, the perception of verticality, and the history of falls in 25 subjects aged 84.5+/-7.4 years was analysed. An original ordinal scale, the BD scale (BDS), was used to quantify BD. Postural (PV) and haptic verticals (HV) were measured in sagittal plane.
Results:
BDS scores closely correlated with the number of falls (r = 0.81, p =10(-5)). The more the PV was tilted backward, the greater the BDS scores (r = -0.95, p<10(-6)), with a huge backward tilt of about 15 degrees in 4 subjects with severe BD. In these subjects, the tilt in perception of verticality was transmodal since a severe backward HV tilt was also found.
Conclusions:
This transmodality suggested high-order cognitive disruption in the construction of the subjective vertical used in postural control by subjects showing BD, which confirmed our hypothesis.
Significance:
This study clearly shows that perception and action with respect to gravity are closely related and brings a new insight about fall mechanisms in the elderly.
