The goldfish ear codes the axis of acoustic particle motion in three dimensions.
Auditory and vestibular nerve fibers of the goldfish are strongly directionally sensitive to whole-body acceleration at audio frequencies. The three-dimensional pattern of sensitivity shows that input from a receptor ensemble (hair cells) is essentially equivalent to that expected from a single hair cell having a given three-dimensional orientation of best sensitivity. Fibers from the sacculus, lagena, and utriculus differ with respect to distributions of directional orientation, but are similar in best threshold (less than 1 nanometer, root mean square, at 140 hertz). In combination with other mechanisms for detection of sound pressure, this directionality is a likely basis for directional hearing in fishes, and it could allow the determination of underwater acoustic intensity.
D000161:Acoustic Stimulation; D000818:Animals; D001306:Auditory Pathways; D001307:Auditory Perception / Q000502:physiology*; D003051:Cochlea / Q000294:innervation* / Q000502:physiology; D003530:Cyprinidae / Q000502:physiology*; D006054:Goldfish / Q000033:anatomy & histology / Q000502:physiology*; D006198:Hair Cells, Auditory / Q000502:physiology*; D012444:Saccule and Utricle / Q000294:innervation* / Q000502:physiology; D013017:Sound Localization / Q000502:physiology*