Does seeing ice really feel cold? Visual-thermal interaction under an illusory body-ownership

Area of Science:

• Neuroscience
• Psychology
• Sensory Perception

Background:

• Visual cues (e.g., color) are anecdotally linked to thermal perception, but empirical evidence for visual-thermal sensory interaction is limited.
• The rubber hand illusion (RHI) demonstrates illusory ownership of a prosthetic limb.
• Illusory thermal sensations have been reported in RHI with apparent thermal visual stimuli.

Purpose of the Study:

• To investigate if body ownership enhances visual-thermal sensory interaction.
• To determine if the perceived ownership of a body surface influences the impact of visual thermal information on tactile thermal perception.

Main Methods:

• Orthogonal manipulation of three variables: induced hand ownership, visual thermal information, and tactile thermal information.
• Utilizing the rubber hand illusion (RHI) paradigm to establish illusory hand ownership.
• Assessing thermal judgments of an object physically touching the hand under different visual and ownership conditions.

Main Results:

• The presence of an apparently-thermal visual stimulus on a rubber hand, when perceived as one's own (RHI), significantly affected thermal judgments of a physically touching object.
• This visual-thermal interaction effect was absent when the RHI was not established.
• Demonstrated a significant role of body ownership in modulating visual-thermal sensory integration.

Conclusions:

• Body ownership is a critical factor in enabling visual-thermal sensory interactions.
• The study provides evidence for a top-down influence of ownership on multisensory integration.
• Findings highlight the importance of the perceived self in shaping sensory experiences, particularly the integration of visual and thermal information.