Proprioceptive uncertainty promotes the rubber hand illusion

Area of Science:

• Neuroscience
• Cognitive Science
• Psychology

Background:

• Body ownership is the multisensory perception of one's body.
• Bayesian causal inference models explain body ownership illusions by assessing the probability of common sources for visual and tactile signals.
• Proprioception, the sense of body position, is crucial for body ownership perception.

Purpose of the Study:

• To investigate how proprioceptive information and its reliability influence the Bayesian causal inference process in body ownership perception.
• To examine the impact of proprioceptive noise on the emergence of the rubber hand illusion.

Main Methods:

• Utilized a detection task based on the rubber hand illusion.
• Manipulated visual-tactile stimulus synchrony and introduced proprioceptive noise via tendon vibration to the forearm.
• Assessed participants' reports on whether the rubber hand felt like their own.

Main Results:

• The probability of the rubber hand illusion increased with higher levels of proprioceptive noise.
• The observed results were well-fitted by a Bayesian causal inference model.
• The findings indicated a shift in the a priori probability of a common cause for vision and touch due to proprioceptive uncertainty.

Conclusions:

• Proprioceptive uncertainty significantly shapes multisensory perception of one's own body.
• The brain's inference about body ownership is influenced by the reliability of proprioceptive signals.
• These findings provide new insights into the mechanisms underlying body ownership and self-perception.