PT - JOURNAL ARTICLE AU - Kevin R. Measor AU - Brian C. Leavell AU - Dustin H. Brewton AU - Jeffrey Rumschlag AU - Jesse R. Barber AU - Khaleel A. Razak TI - Matched Behavioral and Neural Adaptations for Low Sound Level Echolocation in a Gleaning Bat, <em>Antrozous pallidus</em> AID - 10.1523/ENEURO.0018-17.2017 DP - 2017 Jan 01 TA - eneuro PG - ENEURO.0018-17.2017 VI - 4 IP - 1 4099 - http://www.eneuro.org/content/4/1/ENEURO.0018-17.2017.short 4100 - http://www.eneuro.org/content/4/1/ENEURO.0018-17.2017.full SO - eNeuro2017 Jan 01; 4 AB - In active sensing, animals make motor adjustments to match sensory inputs to specialized neural circuitry. Here, we describe an active sensing system for sound level processing. The pallid bat uses downward frequency-modulated (FM) sweeps as echolocation calls for general orientation and obstacle avoidance. The bat’s auditory cortex contains a region selective for these FM sweeps (FM sweep-selective region, FMSR). We show that the vast majority of FMSR neurons are sensitive and strongly selective for relatively low levels (30-60 dB SPL). Behavioral testing shows that when a flying bat approaches a target, it reduces output call levels to keep echo levels between ∼30 and 55 dB SPL. Thus, the pallid bat behaviorally matches echo levels to an optimized neural representation of sound levels. FMSR neurons are more selective for sound levels of FM sweeps than tones, suggesting that across-frequency integration enhances level tuning. Level-dependent timing of high-frequency sideband inhibition in the receptive field shapes increased level selectivity for FM sweeps. Together with previous studies, these data indicate that the same receptive field properties shape multiple filters (sweep direction, rate, and level) for FM sweeps, a sound common in multiple vocalizations, including human speech. The matched behavioral and neural adaptations for low-intensity echolocation in the pallid bat will facilitate foraging with reduced probability of acoustic detection by prey.