Full body aero-tactile integration in speech perception

We follow up on our research demonstrating that aerotactile information can enhance or interfere with accurate auditory perception, even among uninformed and untrained perceivers [1]. Mimicking aspiration, we applied slight, inaudible air puffs on participants’ skin at the ankle, simultaneously with syllables beginning with aspirated (‘pa’, ‘ta’) and unaspirated (‘ba’, ‘da’) stops, dividing the participants into two groups, those with hairy, and those with hairless ankles. Since hair follicle endings (mechanoreceptors) are used to detect air turbulence [2] we expected, and observed, that syllables heard simultaneously with cutaneous air puffs would be more likely to be heard as aspirated, but only among those with hairy ankles. These results demonstrate that information from any part of the body can be integrated in speech perception, but the stimuli must be unambiguously relatable to the speech event in order to be integrated into speech perception.