Research has suggested that altering the perceived\ud
shape and size of the body image significantly\ud
affects perception of somatic events. The current study\ud
investigated how multisensory illusions applied to the body\ud
altered tactile perception using the somatic signal detection\ud
task. Thirty-one healthy volunteers were asked to report the\ud
presence or absence of near-threshold tactile stimuli delivered\ud
to the index finger under three multisensory illusion\ud
conditions: stretched finger, shrunken finger and detached\ud
finger, as well as a veridical baseline condition. Both\ud
stretching and shrinking the stimulated finger enhanced\ud
correct touch detections; however, the mechanisms underlying\ud
this increase were found to be different. In contrast,\ud
the detached appearance reduced false touch reports—possibly\ud
due to reduced tactile noise, as a result of attention\ud
being directed to the tip of the finger only. These findings\ud
suggest that distorted representations of the body could\ud
have different modulatory effects on attention to touch and\ud
provide a link between perceived body representation and\ud
somatosensory decision-making