The relationship between collisions and pseudoneglect: is it right?

When walking through narrow doorways people collide more frequently on the right side than on the left. This rightward collision bias has been attributed to pseudoneglect. Originally pseudoneglect was defined as leftward errors on a line bisection task; however, the term is used more broadly now to refer to the slight tendency to neglect the right side of space and attend more towards the left. Thus, rightward collisions are said to occur because the right side is neglected. In the present experiments, we examined this pseudoneglect hypothesis by assessing the influence of three factors (age, cuing, and motor activity) known to affect performance on traditional measures of pseudoneglect, such as line bisection tasks. Navigation and line bisection tasks were completed by younger and older adults performing a concurrent motor task (Experiment 1) and by younger adults performing no concurrent motor task (Experiment 2). In both experiments, attention was cued to the left, right, or both sides of space, or was uncued. In contrast to previous reports, in both experiments we found a leftward collision bias on the navigation task; this bias was relatively unaffected by age or cuing manipulations, and was attenuated by concurrent motor activity. In addition, we found no relation between performance on the navigation and line-bisection tasks, indicating that the leftward bias on the navigation task cannot be attributed to pseudoneglect. We provide alternative hypotheses that may explain differences between our results and those observed in others' studies.