An experiment was carried out to evaluate the vibrotactile recognition of musical scales produced by an harmonium. The stimuli consisted of four scales played by an Indian performer living in Europe: two western, and two oriental. After listening to the scales without touching the harmonium during a training session, subjects had to put their hands on the instrument and wear headphones emitting a masking noise. Under such conditions they evaluated the same scales, played by the same performer. The experiment was made in Italy and then repeated in India, involving native population groups. Results reveal ability of both groups to recognize the ethnic origin of the scales, limitedly to musicians and with no significant differences between groups. The surprisingly high performance level may suggest possible support during the task of auditory cues capable to bypass the masking noise through bone conduction, and/or perceptual bias due to temporal nuances introduced by the performer. More intriguing appears the hypothesis on possibilities for the musicians to draw from a well-developed tactile memory for tones or harmonic series, result of the training on their acoustic musical instrument. Further experiments would be needed to clarify the importance of touch in the recognition of musical scales, especially for multimodal interface designs in which such temporal patterns may bring significant vibrotactile information to users.
