Eccentric eye and head positions in darkness induce deviation from the intended path

Head and gaze are aligned with the actual path during locomotion. Before a turn is made, gaze changes in the direction of the planned trajectory. We investigated whether eccentric horizontal head and/or eye position without vision causes deviations from the intended straight path. Twenty blindfolded healthy volunteers were asked to walk toward a previously seen target 10 m straight ahead. Various combinations of head and eye positions were tested (eye-in-head gaze straight ahead or 35 deg left or right with head straight ahead or 70 deg left or right). Head rotation to the left caused a gait deviation to the rig…