The Masked ABR (mABR): a New Measurement Method for the Auditory Brainstem Response

AbstractThe auditory brainstem response (ABR) is relatively non-invasive, and in many species, the only practical way to assess auditory sensitivity. The two main methods for measuring ABR are using either transients or tone bursts as a stimulus. The transient stimulus produces strong neural responses that contain no frequency information. In contrast, tone bursts stimulate only a small part of the auditory system, eliciting weaker neural responses but supplying frequency information. Furthermore, short tone bursts become less and less frequency specific with increasing stimulus wavelength, making them unsuitable for testing low-frequency hearing. Here, we develop a method that can measure sensitivity to both low and high-frequency stimuli. The method is based on masking of a transient response by long-duration sinusoids. The measurement system is developed as a highly portable system that runs on battery power. It has been used in a variety of animals in our lab and in the field, including squid (Mooney et al. in J Exp Biol 213: 3748 –3759,2010), lungfish (Christensen-Dalsgaard et al. in J Neurophys 105: 1992 –2004,2011b), alligators (Bierman et al. in J Exp Biol 217: 1094 –1107,2014), and mink (Brandt et al. in J Exp Biol 216: 3542 –3550,2013). Here, we present data recorded from Tokay geckos and compare the results with tone burst ABR measurements. This method produces results comparable to tone burst stimulations at higher frequencies (above 1  kHz) but has sever...

Source: JARO - Journal of the Association for Research in Otolaryngology - September 20, 2018 Category: ENT & OMF Source Type: research