For younger and older adults in the wakeful rest and perceptual task delay conditions, the table shows (i) mean number of errors (wrong turns) made during route learning probe trials (standard deviations are shown in parentheses), and (ii) number of participants who performed at criterion (i.e. zero errors) in each probe trial relative to the number of participants who completed each probe trial. *One older adult in the rest group and one older adult in the task group exited the learning phase after Probe trial 1 due to nausea associated with the virtual reality equipment. These participants made zero errors in Probe trial 1.