Comparison of the haptic and visual deviations in a parallelity task

Abstract

Deviations in both haptic and visual spatial experiments are thought to be caused by a biasing influence of an egocentric reference frame. The strength of this influence is strongly participant-dependent. By using a parallelity test, it is studied whether this strength is modality-independent. In both haptic and visual conditions, large, systematic and participant-dependent deviations were found. However, although the correlation between the haptic and visual deviations was significant, the explained variance due to a common factor was only 20%. Therefore, the degree to which a participant is "egocentric" depends on modality and possibly even more generally, on experimental condition.

Fig. 1

Deviations obtained in the haptic and visual conditions for all 32 participants, ordered by the size of the deviation in the haptic condition. Deviations are averaged over all 32 trials of a participant. Error bars indicate standard deviations

Fig. 2

Visual and haptic deviations as a function of reference orientation and averaged over all female or male participants. Error bars indicate standard errors