Article

Click-Evoked Auditory Brainstem Responses in an Australian Sea Lion (Neophoca cinerea)

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  • JASCO Applied Sciences, Australia
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Abstract

A single male Australian sea lion (Neophoca cinerea) was tested for its auditory sensitivity to in air sound. Short, broadband clicks were presented via headphones while the animal was immobilized during medical treatment. Click-evoked auditory brainstem responses (ABRs) were recorded in the animal after acoustic stimulation at decreasing sound pressure levels. A single wave was clearly and repeatedly identified in the neuronal responses and analyzed. Click-evoked brainstem activity was detectable in the presence of ambient and electrical noise at presentation levels down to 81 dB re 20 µPa peak equivalent sound pressure level for in air stimuli. As has been previously demonstrated for other pinniped species, this method is applicable for Australian sea lions and will be useful for auditory studies of individuals in captivity and in the field.

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