Presentation of music as vibration to the skin has the potential to facilitate interaction between musicians with hearing impairments and other musicians during group performance. Vibrotactile thresholds have been determined to assess the potential for vibrotactile presentation of music to the glabrous skin of the fingertip, forefoot and heel. No significant differences were found between the thresholds for sinusoids representing notes between C1 and C6 when presented to the fingertip of participants with normal hearing and with a severe or profound hearing loss. For participants with normal hearing, thresholds for notes between C1 and C6 showed the characteristic U-shape curve for the fingertip, but not for the forefoot and heel. Compared to the fingertip, the forefoot had lower thresholds between C1 and C3, and the heel had lower thresholds between C1 and G2; this is attributed to spatial summation from the Pacinian receptors over the larger contactor area used for the forefoot and heel. Participants with normal hearing assessed the perception of high-frequency vibration using 1s sinusoids presented to the fingertip and were found to be more aware of transient vibration at the beginning and/or end of notes between G4 and C6 when stimuli were presented 10dB above threshold, rather than at threshold. An average of 94% of these participants reported feeling continuous vibration between G4 and G5 with stimuli presented 10dB above threshold. Based on the experimental findings and consideration of health effects relating to vibration exposure, a suitable range of notes for vibrotactile presentation of music is identified as being from C1 to G5. This is more limited than for human hearing but the fundamental frequencies of the human voice, and the notes played by many instruments, lie within it. However, the dynamic range might require compression to avoid the negative effects of amplitude on pitch perception.

This study investigated the perception and learning of relative pitch using vibrotactile stimuli by musicians with and without a hearing impairment. Notes from C3 to B4 were presented to the fingertip and forefoot. Pre- and post-training tests in which 420 pairs of notes were presented randomly were carried out without any feedback to participants. After the pre-training test, 16 short training sessions were carried out over six weeks with 72 pairs of notes per session and participants told whether their answers were correct. For amateur and professional musicians with normal hearing and professional musicians with a severe or profound hearing loss, larger pitch intervals were easier to identify correctly than smaller intervals. Musicians with normal hearing had a high success rate for relative pitch discrimination as shown by pre- and post-training tests, and when using the fingertips, there was no significant difference between amateur and professional musicians. After training, median scores on the tests in which stimuli were presented to the fingertip and forefoot were >70% for intervals of 3–12 semitones. Training sessions reduced the variability in the responses of amateur and professional musicians with normal hearing and improved their overall ability. There was no significant difference between the relative pitch discrimination abilities between one and 11 semitones, as shown by the pre-training test, of professional musicians with and without a severe/profound hearing loss. These findings indicate that there is potential for vibration to be used to facilitate group musical performance and music education in schools for the deaf.

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Performing music or singing together provides people with great pleasure. But if you are deaf (or hard of hearing) it is not always possible to listen to other musicians while trying to sing or play an instrument. It can be particularly difficult to perceive different musical pitches with a hearing aid or other hearing-assistance device. However, the human body can transmit musical sounds to the brain when vibrations are applied to the skin. In other words, we can feel music. Our research has identified a safe way for deaf people to hear musical notes through the skin of their hands and feet. We have shown that vibration allows people to safely feel music on the skin. This approach allows people to identify a musical note as being higher or lower in pitch than other notes, and it helps musicians to play music together.