Abstract
<title>Abstract</title> <p> Cortical auditory evoked potentials (CAEPs) provide a minimally invasive approach for investigating hearing in naturally behaving small animals. Previous research in anesthetized rodents and one species of bat identified two discrete middle-latency peaks in the CAEP waveform that correlated with activation of primary auditory cortex (P1) and a secondary auditory field (P2). However, anesthesia differentially suppresses thalamocortical activity and precludes attentional processes, hiding important elements of the neural signal processing chain from the CAEP waveform. To address this limitation, CAEPs were recorded and compared from both anesthetized and awake, Jamaican fruit bats ( <italic>Artibeus jamaicensis</italic> ) using chronically implanted subdermal electrodes. Recordings from 6 anesthetized bats confirmed that this frugivorous bat species displayed CAEP waveforms qualitatively similar to those obtained from mice and insectivorous bats, including 2 prominent middle-latency peaks. CAEP waveforms obtained from awake, freely moving bats closely resemble those from anesthetized bats, but displayed ~ 17-fold greater amplitudes and roughly 10 dB lower thresholds. These results quantify the effects of isoflurane anesthesia on the middle-latency CAEPs in bats, illustrate that data obtained from anesthetized bats are qualitatively predictive of data obtained from awake bats, and provides the first comparison of CAEPs between two species of bats with different biosonar behaviors. This method may be useful for investigating how auditory cortical networks process spectrotemporally complex auditory signals during natural communication. </p>