One exercise I like to incorporate in training is movement with eyes closed. This is a more advanced way to load up the vestibular system and decrease reliance on the visual system for ownership of movement.
Alternating lunges with eyes closed are a great example of a simple, but not necessarily easy way to train this.
When visual cues are removed during movement, I commonly see individuals lose speed or precision of their movement.
You can see the loss of balance as this individual returns to standing from the lunge and the need to re-right his trunk over center. This typically results in decreased speed of movement to correct and maintain balance/position.
A loss of balance during movement also decreases his ability to maintain his position when generating or experiencing a force and can take attention from acquiring and engaging targets.
Another common issue with increased visual dependence is loss of precision of movement.
You can see loss of precision demonstrated by this individual who turns almost 45 degrees from his starting position in less than 10 seconds of performing alternating lunges with his eyes closed.
Loss of precision of movement and orientation in space can have significant consequences for those who perform in low/no vision environments where every millisecond and millimeter matters.
Maintaining trunk positioning and balance is a key function of the vestibular system and incorporating training its performance is vital for readiness and lethality.