A recent experiment by researchers from Great Britain finds that ongoing visual feedback during walking plays a more critical role than once thought. It was previously believed that vision was crucial only while lifting your foot to take a step and not as important once the target of your step was determined and your foot was in the air. As it turns out, constant visual monitoring is needed to guarantee accurate foot placement while walking. LiveScience.com has an article today about the unexpected results of the study.
During the experiments, led by Dr. Raymond Reynolds and Dr. Brian Day of the Institute of Neurology, Queen Square, London, the researchers recorded how accurately subjects could step on a target while they walked. Half of the time the scientists blocked the subject’s vision immediately after they lifted their foot to take a step. A marked decrease in accuracy was observed in the subjects who had their vision impaired. Their accuracy did return when they were allowed to walk with no visual interruptions.
“Because vision was blocked only after the foot had left the floor, this research shows that we use visual information to adjust our footfall while our foot is moving forwards – it is not simply predetermined at the beginning of the step,” said Dr. Reynolds.
While the fine tuning afforded by constant visual input may not be so important when walking on consistently flat surfaces, it certainly is crucial for navigating inconsistent or rough terrain where a misstep could lead to a fall and injury. Reynolds also beliefs visual guidance is important in athletics citing gymnasts and tightrope walkers as examples.
The doctors hope their work studying foot placement in healthy people will help them understand and treat neurological disorders that affect walking. The next phase of their research entails determining how much ability people have to alter the placement of a step mid-stride.
The study appears in the December issue of the Journal of Physiology.