Gallun Frederick J, Durlach Nathaniel I, Colburn H Steven, Shinn-Cunningham Barbara G, Best Virginia, Mason Christine R, Kidd Gerald
Hearing Research Center, Boston University, 635 Commonwealth Avenue, Boston, Massachusetts 02215, USA.
J Acoust Soc Am. 2008 Jul;124(1):439-49. doi: 10.1121/1.2924127.
Detection was measured for a 500 Hz tone masked by noise (an "energetic" masker) or sets of ten randomly drawn tones (an "informational" masker). Presenting the maskers diotically and the target tone with a variety of interaural differences (interaural amplitude ratios and/or interaural time delays) resulted in reduced detection thresholds relative to when the target was presented diotically ("binaural release from masking"). Thresholds observed when time and amplitude differences applied to the target were "reinforcing" (favored the same ear, resulting in a lateralized position for the target) were not significantly different from thresholds obtained when differences were "opposing" (favored opposite ears, resulting in a centered position for the target). This irrelevance of differences in the perceived location of the target is a classic result for energetic maskers but had not previously been shown for informational maskers. However, this parallellism between the patterns of binaural release for energetic and informational maskers was not accompanied by high correlations between the patterns for individual listeners, supporting the idea that the mechanisms for binaural release from energetic and informational masking are fundamentally different.
检测针对由噪声(一种“能量型”掩蔽声)或十组随机抽取的音调(一种“信息型”掩蔽声)掩蔽的500赫兹纯音进行测量。以各种双耳差异(双耳幅度比和/或双耳时间延迟)双耳呈现掩蔽声以及目标音调,相对于单耳呈现目标音调时(“双耳掩蔽释放”),检测阈值降低。当应用于目标的时间和幅度差异“增强”时(有利于同一耳,导致目标处于偏向位置)观察到的阈值与差异“相反”时(有利于相对的耳,导致目标处于居中位置)获得的阈值没有显著差异。目标感知位置差异的这种无关性是能量型掩蔽声的经典结果,但此前尚未在信息型掩蔽声中得到证明。然而,能量型和信息型掩蔽声的双耳释放模式之间的这种平行性并未伴随着个体听众模式之间的高度相关性,支持了能量型和信息型掩蔽的双耳释放机制根本不同的观点。