When moving in a public place, the elderly use a different pedestrian avoidance strategy than the young, a team from Laval University demonstrates after experiments in a virtual environment. The slower reaction time to adjust their movement could lead to unfortunate consequences.
“Our results suggest that older people need more time to analyze the visual information collected. As a result, their attention is diverted from obstacles that might stand in their way. In older people with mobility or balance problems, this avoidance strategy could increase the risk of hitting an object or taking a wrong step that leads to a fall,” summarizes the professor at the University of Laval Faculty of Medicine and researcher at the Interdisciplinary Institute Research Center for Rehabilitation and Social Integration (Cirris) of the CIUSSS de la Capitale-Nationale, Bradford McFadyen.
To arrive at these results, the team examined the evasion strategies of 14 young people, with an average age of 24, and 14 people older than 70 years. The participants moved in a virtual reality environment that represented a shopping mall.
“We asked them to walk to a grocery counter at a normal pace. During the ride, a virtual pedestrian appeared in their field of vision and walked towards them. Participants had to walk around it,” says Professor McFadyen.
During the tests, the research team measured, among other things, the observation time of the virtual pedestrian, the location at which the participants looked, the distance pedestrian-virtual pedestrian at the initiation of the detour and the minimum distance detour.
Their results showed that older adults:
- Looking at the virtual pedestrian 70% of the time, compared to 50% for young people;
- spend half as much time as young people engaging with the environment;
- spend twice as much time as teenagers watching the virtual pedestrian’s legs;
- start detour later when they are 1 m closer to the virtual pedestrian.
When the virtual pedestrian moved without moving a limb, members of both groups started walking earlier, but the difference was more pronounced in older people. “This indicates that the movements of the virtual pedestrian’s limbs are used to plan the detour. When this information is withheld, participants, especially older people, are more cautious,” says Professor McFadyen.
To improve older people’s avoidance strategy and prevent accidents, Professor McFadyen suggests that the virtual environment used in the study could be used
as a training device for people with reduced mobility due to age or health problems such as stroke. This study was published in the journal Human Movement Science. The signatories are Félix Fiset and Bradford McFadyen from Université Laval and Anouk Lamontagne from McGill University.
Source :
Public Relations and Protocol Team
Laval University
Article from the CIRRIS website