"Next time someone tells you to watch your step, tell them you
already are. Placing your foot down when walking was thought to
be a predetermined process: lift foot, decide where to put it
based on what's on the ground, and if nothing moves, land it
down on the original target. Scientists thought this procedure
requires no immediate visual information once the foot was
lifted off the ground. But a new study has found that continuous
visual guidance mechanisms may be needed for accurate foot
placement. "We have demonstrated that vision can be used in an
online fashion to fine-tune foot placement during a step," said
Raymond Reynolds, of the Institute of Neurology, Queen Square,
London. "It was previously thought that vision was used to plan
the step in advance but not necessarily monitor its ongoing
progress.'" Click the title to read the entire article