Mongolian gerbil, Meriones unguiculatus, has been a good model animal for hearing, whose thresholds between 1 and 16 kHz are low. The animal also has a variety of repertoire in communication calls. Frequency range for 80% of communication calls was reported to be 30–50 kHz. However, the audiogram indicates that thresholds for 30–50 kHz are not low, not well suited for vocal communication. The present study examines if sensitivity for 30–50 kHz could be improved when necessary. We made a hypothesis that their attention might enhance inner ear sensitivity around 30–50 kHz for vocal communication. Then, frequency sensitivity of inner ear was examined by the cochlear microphonics (CM), comparing attended and unattended conditions. The findings suggest that attention to the companion animal may enhance CM power spectra around 30 kHz, especially for low intensities. Moreover, when a companion animal exists, even CM to short simple tone bursts of 25–40 kHz was enhanced. Findings from noise induced TTS experiments would also imply that CM responses around 30 kHz appeared to be amplified by the hair cell activities. [Work supported by Grant-in-Aid for Scientific Research (B) 26280064 from MEXT of Japan and Start-up grant from Shandong University.]