title: Auditory brainstem response of the Japanese house bat (Pipistrellus abramus).
abstract: Auditory brainstem responses (ABR) to high frequencies encompassing the species' vocal repertoire were recorded from the inferior colliculus of the Japanese house bat, Pipistrellus abramus. Amplitudes of tone pips were systematically decreased to obtain a threshold of response at different tone frequencies. The compiled audiogram has a broad U-shape over the frequency range from 4 to 80 kHz, with low thresholds between 20 and 50 kHz. The most sensitive frequency region of 35-50 kHz occurs at the quasi-constant-frequency terminal portion of the bat's downsweeping frequency-modulated echolocation pulses. Good sensitivity extending down to 20 kHz includes the frequency range of the first harmonic of communication sounds. The ABR audiogram does not show distinct, narrow peaks of greater sensitivity at the dominant frequencies in species vocalizations. Latencies of peaks in ABR responses lengthened as stimuli were attenuated. At 40 kHz, response latencies traded with amplitude by -7 to -9 μs/dB, a value smaller than measured in another frequency-modulated bat using lower frequencies for echolocation. These results have implications for understanding the significance of amplitude-latency trading in a comparative context.
authors: Neurosensing and Bionavigation Research Center, Faculty of Life and Medical Sciences, Doshisha University, Kyotonabe 610-0321, Japan.
authors: Shokei
authors: S
authors: Boku
authors: Neurosensing and Bionavigation Research Center, Faculty of Life and Medical Sciences, Doshisha University, Kyotonabe 610-0321, Japan.
authors: Hiroshi
authors: H
authors: Riquimaroux
authors: Department of Cognitive, Linguistic and Psychological Sciences, Brown University, Providence, Rhode Island 02912.
authors: Andrea Megela
authors: AM
authors: Simmons
authors: Department of Neuroscience, Brown University, Providence, Rhode Island 02912.
authors: James A
authors: JA
authors: Simmons
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D001309:Auditory Threshold; D002685:Chiroptera / Q000502:physiology*; D004455:Echolocation; D004569:Electroencephalography; D016057:Evoked Potentials, Auditory, Brain Stem; D007245:Inferior Colliculi / Q000502:physiology*; D010898:Pitch Perception; D011930:Reaction Time; D013018:Sound Spectrography; D013045:Species Specificity; D013997:Time Factors; D014828:Vocalization, Animal