School of Audiology and Speech Sciences, The University of British Columbia, Vancouver, BC, Canada.
Ear Hear. 2009 Dec;30(6):713-5. doi: 10.1097/AUD.0b013e3181b61cc8.
In contrast to the transient (N1-P2) and steady-state (<20 Hz) cortical responses, neither the transient (auditory brain stem response) nor the steady-state (80 Hz) brain stem responses show the binaural masking level difference (BMLD). This study determined behavioral and 40-Hz auditory steady-state response (ASSR) BMLDs for both signal and noise interaural inversions. Results showed clear behavioral BMLD but no 40-Hz ASSR BMLD. However, ASSR amplitudes were significantly smaller in dichotic compared with diotic conditions. Thus, although 40-Hz ASSR thresholds do not reflect the BMLD, the amplitude suppression under dichotic conditions may be a precursor to the subsequent <20-Hz ASSR and behavioral BMLDs.
与瞬态（N1-P2）和稳态（<20 Hz）皮质反应相反，瞬态（听觉脑干反应）和稳态（80 Hz）脑干反应都没有表现出双耳掩蔽级差（BMLD）。本研究确定了信号和噪声的听觉稳态反应（ASSR）的行为和 40-Hz BMLD 。结果表明，行为 BMLD 明显，但 40-Hz ASSR BMLD 不存在。然而，与同听相比，双耳条件下的 ASSR 幅度明显较小。因此，尽管 40-Hz ASSR 阈值不能反映 BMLD，但双耳条件下的振幅抑制可能是随后 <20-Hz ASSR 和行为 BMLD 的前兆。
