The inner ear of teleost fishes is composed of three paired multimodal otolithic end organs (saccule, utricle, and lagena), which encode auditory and vestibular inputs via the deflection of hair cells contained within the sensory epithelia of each organ. However, it remains unclear how the multimodal otolithic end organs of the teleost inner ear simultaneously integrate vestibular and auditory inputs. Therefore, microwire electrodes were chronically implanted using a 3-D printed micromanipulator into the utricular nerve of oyster toadfish (Opsanus tau) to determine how utricular afferents respond to conspecific mate vocalizations termed boatwhistles (180 Hz fundamental frequency) during movement. Utricular afferents were recorded while fish were passively moved using a sled system along an underwater track at variable speeds (velocity: 4.0–12.5 cm/s; acceleration: 0.2–2.6 cm/s2) and while fish freely swam (velocity: 3.5–18.6 cm/s; acceleration: 0.8–29.8 cm/s2). Afferent fiber activities (spikes/s) increased in response to the onset of passive and active movements; however, afferent fibers differentially adapted to sustained movements. In addition, utricular afferent fibers remained sensitive to playbacks of conspecific male boatwhistle vocalizations during both passive and active movements. Here, we demonstrate in alert toadfish that utricular afferents exhibit enhanced activity levels (spikes/s) in response to behaviorally relevant acoustic stimuli during swimming.
Bibliographical noteFunding Information:
The authors acknowledge the Marine Resources Center staff at the Marine Biological Laboratory for providing toadfish care. The authors also acknowledge Dr. Joseph Sisneros for helpful comments on the manuscript, Dr. Geoffrey Boynton for statistical consultation, and Dr. Steve Zottoli for providing the image of the toadfish brain and inner ear used in Fig. 1B. Funding was provided by National Science Foundation Grants IOS 1354745 and DBI 1359230 & 1659604 (to A. F. Mensinger) and by the National Science Foundation Graduate Research Fellowship Program DGE 1762114 (to L. S. Rogers). All experimental procedures conformed to NIH guidelines for animal care and use of animals and were approved by the Marine Biological Laboratories Institutional Animal Care and Use Committee.
Funding was provided by National Science Foundation Grants IOS 1354745 and DBI 1359230 & 1659604 (to A. F. Mensinger) and by the National Science Foundation Graduate Research Fellowship Program DGE 1762114 (to L. S. Rogers). All experimental procedures conformed to NIH guidelines for animal care and use of animals and were approved by the Marine Biological Laboratories Institutional Animal Care and Use Committee.
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- fish hearing
PubMed: MeSH publication types
- Journal Article
- Research Support, U.S. Gov't, Non-P.H.S.