Objective: The perception of pitch has recently gained attention. At present, clinical audiologic tests to assess this are hardly available. This article reports on the development of a clinical test using harmonic intonation (HI) and disharmonic intonation (DI).
Study design: Prospective collection of normative data and pilot study in hearing-impaired subjects.
Setting: Tertiary referral center.
Patients: Normative data were collected from 90 normal-hearing subjects recruited from 3 different language backgrounds. The pilot study was conducted on 18 hearing-impaired individuals who were selected into 3 pathologic groups: high-frequency hearing loss (HF), low-frequency hearing loss (LF), and cochlear implant users (CI).
Intervention(s): Normative data collection and exploratory diagnostics by means of the newly constructed HI/DI tests using intonation patterns to find the just noticeable difference (JND) for pitch discrimination in low-frequency harmonic complex sounds presented in a same-different task.
Main outcome measure(s): JND for pitch discrimination using HI/DI tests in the hearing population and pathologic groups.
Results: Normative data are presented in 5 parameter statistics and box-and-whisker plots showing median JNDs of 2 (HI) and 3 Hz (DI). The results on both tests are statistically abnormal in LF and CI subjects, whereas they are not significantly abnormal in the HF group.
Conclusion: The HI and DI tests allow the clinical assessment of low-frequency pitch perception. The data obtained in this study define the normal zone for both tests. Preliminary results indicate possible abnormal TFS perception in some hearing-impaired subjects.