Otoacoustic emissions in African mole-rats

Geoffrey A. Manley, Bert Maat, Sabine Begall, Pascal Malkemper, Kai R. Caspar, Leif Moritz, Pim van Dijk

Research output: Contribution to journalArticlepeer-review

Abstract

African mole-rats display highly derived hearing that is characterized by low sensitivity and a narrow auditory range restricted to low frequencies < 10 kHz. Recently, it has been suggested that two species of these rodents do not exhibit distortion product otoacoustic emissions (DPOAE), which was interpreted as evidence for a lack of cochlear amplification. If true, this would make them unique among mammals. However, both theoretical considerations on the generation of DPOAE as well as previously published experimental evidence challenge this assumption. We measured DPOAE and stimulus-frequency otoacoustic emissions (SFOAE) in three species of African mole-rats (Ansell's mole-rat - Fukomys anselli; Mashona mole-rat - Fukomys darlingi; naked mole-rat - Heterocephalus glaber) and found unexceptional otoacoustic emission values. Measurements were complicated by the remarkably long, narrow and curved external ear canals of these animals, for which we provide a morphological description. Both DPOAE and SFOAE displayed the highest amplitudes near 1 kHz, which corresponds to the region of best hearing in all tested species, as well as to the frequency region of the low-frequency acoustic fovea previously described in Ansell's mole-rat. Thus, the cochlea in African mole-rats shares the ability to generate evoked otoacoustic emission with other mammals.

Original languageEnglish
Article number108994
JournalHearing Research
Volume445
DOIs
StatePublished - Apr 2024
Externally publishedYes

Keywords

  • DPOAE
  • Mole-rats
  • Otoacoustic emissions
  • Rodent hearing
  • SFOAE

Fingerprint

Dive into the research topics of 'Otoacoustic emissions in African mole-rats'. Together they form a unique fingerprint.

Cite this