The role of vision and proprioception in self-motion encoding: An immersive virtual reality study.

Past research on the advantages of multisensory input for remembering spatial information has mainly focused on memory for objects or surrounding environments. Less is known about the role of cue combination in memory for own body location in space. In a previous study, we investigated participants' accuracy in reproducing a rotation angle in a self-rotation task. Here, we focus on the memory aspect of the task. Participants had to rotate themselves back to a specified starting position in three different sensory conditions: a blind condition, a condition with disrupted proprioception, and a condition where both vision and proprioception were reliably available. To investigate the difference between encoding and storage phases of remembering proprioceptive information, rotation amplitude and recall delay were manipulated. The task was completed in a real testing room and in immersive virtual reality (IVR) simulations of the same environment. We found that proprioceptive accuracy is lower when vision is not available and that performance is generally less accurate in IVR. In reality conditions, the degree of rotation affected accuracy only in the blind condition, whereas in IVR, it caused more errors in both the blind condition and to a lesser degree when proprioception was disrupted. These results indicate an improvement in encoding own body location when vision and proprioception are optimally integrated. No reliable effect of delay was found.