Abstract
Full and accurate sensory information facilitates human spatial orientation and balance control. This study investigates how unisensory and multisensory information influences people’s skill at manually balancing an object. Adults with normal hearing, vision, and balancing skills performed the balance task on a computer by controlling a joystick. The object to be balanced was a virtual inverted pendulum, and it was presented in visual, auditory, or both modalities. The visual presentation was a ball on top of a pole pivoting at its base; the auditory modality was produced by manipulating the amplitude of sound from two speakers on each side of the computer. The coherent visual and auditory cues were combined in the multisensory conditions. Different gravity levels were used to manipulate the falling rate of the pendulum. Participants experienced all factorial combinations of the 3 sensory modalities and 2 gravity levels in each of three blocks of eight 30-second trials. The results indicated that auditory cues facilitated balance control less than visual and combined cues. Participants’ performances were the same in the visual and combined conditions, indicating that the auditory cues did not interfere with the visual cues. In addition, gravity levels influenced balance control; a higher gravity level led to more falls. Our findings suggest that visual information is the primary source when people balance a virtual object, while auditory information has a potential benefit closely related to multisensory integration.
Keywords: Balance, virtual inverted pendulum, auditory cueing, multisensory integration