Kinaesthetic mirror illusion and spatial congruence

Area of Science:

• Neuroscience
• Perception Science
• Human Motor Control

Background:

• Position sense and kinaesthesia rely on integrating somaesthetic and visual information.
• Visual input can dominate perception, especially in mirror paradigms, creating kinaesthetic illusions.

Purpose of the Study:

• To investigate if kinaesthetic illusions in the mirror paradigm adhere to spatial congruence rules of multisensory integration.
• To determine how spatial incongruence between visual and proprioceptive signals affects kinaesthetic illusions.

Main Methods:

• Participants experienced kinaesthetic illusions induced by a reflected moving arm while their unseen arm remained static.
• The static arm was positioned parallel or at varying degrees of incongruence (15°-90°) relative to the moving reflected arm.

Main Results:

• Kinaesthetic illusion frequency decreased slightly with increasing spatial incongruence but remained high.
• Greater incongruence delayed illusion onset and reduced its perceived speed.

Conclusions:

• While vision dominates visuoproprioceptive conflict, the brain dynamically adjusts signal weightings based on spatial incongruence.
• The degree of pre-movement spatial mismatch influences the perception and timing of kinaesthetic illusions.