Feeling Touch Through Glass: A Modified Rubber Hand Paradigm

Abstract

A variation on the rubber hand paradigm creates a striking illusion in which it seems to the participant that she or he is feeling touch through glass. This illusion provides insight about how individuals make use of predictive signals for integrating vision and touch.

Keywords: body representation; predictive signals; rubber hand illusion; tactile congruency.

Figure 1.

The experimental set-up. The participant’s left hand was positioned on the glass table top to the left of the visual divider. The prosthetic left hand was positioned beneath the glass table top to the right of the visual divider. The participant was seated so that the visual divider was in line with the participant’s left shoulder, thereby preventing the participant from seeing her or his own left hand. Note that a piece of cloth, placed on top of the table, concealed the arm of the prosthetic hand.

Figure 2.

Mean agreement ratings for Botvinick and Cohen’s (1998) questionnaire. Statements 1 to 3 in the figure assessed the illusion (visual capture, causation, ownership) and Statements 4 to 9 were included to control for suggestibility. (Note that the order of statements was randomized.) Agreement ratings were provided on a 7-point scale ranging from 0 (not at all) to 6 (very strongly agree).