Yost William A
Speech and Hearing Science, Arizona State University, P.O. Box 870102, Tempe, Arizona 85287, USA.
J Acoust Soc Am. 2017 Mar;141(3):2093. doi: 10.1121/1.4978614.
Spatial Release from Masking (SRM) was measured for identification of a female target word spoken in the presence of male masker words. Target words from a single loudspeaker located at midline were presented when two, four, or six masker words were presented either from the same source as the target or from spatially separated masker sources. All masker words were presented from loudspeakers located symmetrically around the centered target source in the front azimuth hemifield. Three masking conditions were employed: speech-in-speech masking (involving both informational and energetic masking), speech-in-noise masking (involving energetic masking), and filtered speech-in-filtered speech masking (involving informational masking). Psychophysical results were summarized as three-point psychometric functions relating proportion of correct word identification to target-to-masker ratio (in decibels) for both the co-located and spatially separated target and masker sources cases. SRM was then calculated by comparing the slopes and intercepts of these functions. SRM decreased as the number of symmetrically placed masker sources increased from two to six. This decrease was independent of the type of masking, with almost no SRM measured for six masker sources. These results suggest that when SRM is dependent primarily on binaural processing, SRM is effectively limited to fewer than six sound sources.
在存在男性掩蔽词的情况下，测量了空间掩蔽释放（SRM），以识别女性目标词。当两个、四个或六个掩蔽词从与目标相同的声源或空间分离的掩蔽声源呈现时，呈现来自位于中线的单个扬声器的目标词。所有掩蔽词均由位于前方位半场中围绕中心目标声源对称放置的扬声器呈现。采用了三种掩蔽条件：语音中语音掩蔽（涉及信息掩蔽和能量掩蔽）、语音中噪声掩蔽（涉及能量掩蔽）和滤波语音中滤波语音掩蔽（涉及信息掩蔽）。心理物理学结果总结为三点心理测量函数，该函数将正确单词识别的比例与共置和空间分离的目标声源和掩蔽声源情况下的目标与掩蔽比（以分贝为单位）相关联。然后通过比较这些函数的斜率和截距来计算SRM。随着对称放置的掩蔽声源数量从两个增加到六个，SRM降低。这种降低与掩蔽类型无关，对于六个掩蔽声源几乎没有测量到SRM。这些结果表明，当SRM主要依赖双耳处理时，SRM有效地限制在少于六个声源。
