Bloch M I, Hellige J B
Department of Psychology, University of Southern California, Los Angeles 90089-1061.
Brain Cogn. 1989 Jan;9(1):136-48. doi: 10.1016/0278-2626(89)90049-3.
The present experiment was designed to investigate the effects of the following two variables on the identification of dichotically presented CV syllables: (1) the relative difference in intensity levels of the stimuli presented to the two ears and (2) the instructions to attend to both ears or to focus attention on one ear. As expected for a verbal task, more CV's were identified from the right ear than from the left ear. Furthermore, identification of stimuli presented to one ear improved when (1) those stimuli were relatively higher in volume than the stimuli presented to the other ear and (2) when subjects were instructed to focus attention on only that ear rather than distribute attention across both ears. Of particular importance is the finding that the effects of relative stimulus intensity are the same under conditions of focused attention as under conditions of divided attention. This finding is inconsistent with an attention explantation of the relative intensity effects. Instead, the results are consistent with a model of dichotic listening in which ear of stimulus presentation and relative stimulus intensity influence a perceptual stage of information processing and attentional instructions influence a subsequent response selection stage.
本实验旨在研究以下两个变量对双耳呈现的CV音节识别的影响：（1）呈现给两只耳朵的刺激强度水平的相对差异；（2）关注两只耳朵或专注于一只耳朵的指令。正如言语任务所预期的那样，从右耳识别出的CV音节比左耳更多。此外，当（1）呈现给一只耳朵的那些刺激在音量上相对高于呈现给另一只耳朵的刺激，以及（2）当受试者被指示仅专注于那只耳朵而不是将注意力分散到两只耳朵时，对呈现给一只耳朵的刺激的识别得到了改善。特别重要的是这一发现：在集中注意力条件下，相对刺激强度的影响与在分散注意力条件下相同。这一发现与对相对强度效应的注意力解释不一致。相反，结果与一种双耳分听模型一致，在该模型中，刺激呈现的耳朵和相对刺激强度影响信息处理的感知阶段，而注意力指令影响随后的反应选择阶段。
