Blindfolded adults use mental transformation strategies for spatial scaling of tactile maps

The current study tested strategies of spatial scaling in the haptic domain. Blindfolded adults (N = 31, aged 20-24 years) were presented with an embossed graphic including a target and asked to encode a target location on this map, imagine this map at a given scale, and to localize a target at the same spot on an empty referent space. Maps varied in three different sizes whereas the referent space had a constant size, resulting in three different scaling factors (1:1, 1:2, 1:4). Participants' response times and localization errors were measured. Analyses indicated that both response times and errors increased with higher scaling factors, suggesting the usage of mental transformation stratergies for spatial scaling. Overall, the present study provides a suitable, novel methodology to assess spatial scaling in the haptic domain.