Gravitoinertial force versus the direction of balance in the perception and control of orientation.

Curthoys and Wade (1990) appeal to land-based data in defending the traditional view that stimulation of the otolith organs leads to perception of the direction of gravitoinertial force. However, such data do not permit rejection of the hypothesis that the perception of orientation is based on the dynamically defined direction of balance, which is qualitatively different from the kinetically defined direction of gravitoinertial force. Furthermore, the approach of Curthoys and Wade is compromised by their failure to consider relations between the perception and control of orientation. Such relations must be considered in developing a general theory of orientation.