Hand Temperature Is Not Consistent With Illusory Strength During the Rubber Hand Illusion

Area of Science:

• Neuroscience
• Psychology
• Somatosensory research

Background:

• The rubber hand illusion (RHI) is a well-established phenomenon demonstrating the sense of ownership over an artificial limb.
• Quantifying the subjective experience of ownership in RHI is typically done via questionnaires.
• There is ongoing research into reliable physiological biomarkers for RHI ownership.

Purpose of the Study:

• To investigate the potential of hand skin temperature as a physiological biomarker for the strength of the rubber hand illusion.
• To determine if changes in hand temperature correlate with the subjective sense of ownership during the RHI.

Main Methods:

• Participants underwent the rubber hand illusion experiment.
• Thermal imaging was used to record hand skin temperature during the illusion.
• Reported illusory strength was measured using standard questionnaires.
• Correlation analysis was performed between skin temperature and reported illusory strength.

Main Results:

• No significant relationship was found between reported illusory strength and measured skin temperature of the hand.
• Skin temperature did not vary in accordance with the perceived strength of the rubber hand illusion.

Conclusions:

• Skin temperature is not a suitable physiological biomarker for quantifying the strength of the rubber hand illusion.
• Further research is needed to identify reliable objective measures for the sense of ownership in somatosensory illusions.