According to a pilot study published in the 'Patient Education and Counseling', it is possible to differentiate pain stimuli non-verbally through tones. However, the factor responsible (quality or intensity) for this differentiation is still not known.

For effective chronic pain treatment, not only measuring the quality but its intensity is also necessary. Hence, Patric Bialas et al. examined the non-verbal description of pain quality as per the tones, differentiating between the nociceptive and neuropathic pain.

A total of 80 chronic pain patients and 80 healthy subjects were given nociceptive and a neuropathic pain stimulus. All the participants matched both pain stimuli to an appropriate tone (in Hz) via a tone generator. The NRS-scale and the PainDETECT questionnaire was used to measure the stimulus intensity.

 It was found that both the groups matched a significantly higher tone to the neuropathic as compared to the nociceptive pain stimulus. The chronic pain patients allocated higher tones to both pain stimuli as compared to the healthy participants. Higher values were also revealed for the neuropathic pain stimulus, and chronic pain patients portraying an overall higher intensity of pain as healthy participants.