Computerized Vestibular Rehabilitation

The vestibulo-ocular reflex gain is the relationship between a rotation of the head and the evoked eye movement. The outcome measure is the ratio of the VOR gain after training to that before training. VOR gain is determined by a scaled fit of eye speed to evoking head speed (normal gain is 1). Note that this experiment was not a treatment of impairment but a test of the ability of the vestibular game to elicit motor learning (away from normal) in individuals with intact motor learning. In that context, an increase in the gain to a value greater than unity (faster eye movement relative to the head movement) is better with respect to the training goal, but it is not better with respect to real-world visual function, for which a gain of one is the goal. There is no threshold value for this type of motor learning experiment. Instead, the question is whether the gain is increased after training, and if so, by what percentage relative to the training goal.

Time frame: VOR measurements to determine gain were performed immediately before and after each approximately 30 minute training session. Pre- and post-training gains were then combined in the VOR gain ratio to determine the training effect.

Population: This measure applied only to Group 1: healthy individuals with intact vestibular function

Participants with vestibular hypofunction rated their nausea after each game block on a scale of 1 to 10. For each visit, there were up to 3 game-blocks, each of 10-minutes duration. The number of blocks was determined by the participant. A higher score is a worse outcome (more nausea). The average nausea scale rating was determined for each participant. The final result is the median of these averaged scores.

Time frame: Immediately after each 10-minute game block, median value calculated for each participant

Population: This measure applied only to Group 2: participants with vestibular dysfunction. Of the 6 enrolled participants in this group, one chose not to complete the game playing after consenting, and a second was found to have recovery of his vestibular function before game playing. The reported data are from the remaining four participants.