Delogu Franco, McMurray Phillip
Lawrence Technological University, Southfield, MI, USA.
Cogn Process. 2019 Nov;20(4):479-494. doi: 10.1007/s10339-019-00922-1. Epub 2019 Jun 13.
Few studies have examined the stability of the representation of the position of sound sources in spatial working memory. The goal of this study was to verify whether the memory of sound position declines as maintenance time increases. In two experiments, we tested the influence of the delay between stimulus and response in a sound localization task. In Experiment 1, blindfolded participants listened to bursts of white noise originating from 16 loudspeakers equally spaced in a 360-degree circular space around the listener in such a way that the nose was aligned to the zero-degree coordinate. Their task was to indicate sounds' position using a digital pointer when prompted at varying delays: 0, 3, and 6 s after stimulus offset. In Experiment 2, the task was analogous to Exp. 1 with stimulus-response delays of 0 or 10 s. Results of the two experiments show that increasing stimulus-response delays up to 10 s do not impair sound localization. Participants systematically overestimated the eccentricity of the auditory stimulus by shifting their responses either toward the 90-degree coordinate, in alignment with the right ear, or toward the 270-degree coordinate, in alignment with the left ear. Such bias was analogous in the front and in the rear azimuthal space and was only marginally influenced by the delay conditions. We conclude that the representation of auditory space in working memory is stable, but directionally biased with systematic overestimation of eccentricity.
很少有研究考察空间工作记忆中声源位置表征的稳定性。本研究的目的是验证声音位置的记忆是否会随着保持时间的增加而下降。在两个实验中,我们测试了声音定位任务中刺激与反应之间延迟的影响。在实验1中,蒙住眼睛的参与者聆听来自16个扬声器发出的白噪声脉冲,这些扬声器在听众周围360度的圆形空间中均匀分布,使鼻子与零度坐标对齐。他们的任务是在不同延迟(刺激消失后0、3和6秒)提示时,用数字指针指示声音的位置。在实验2中,任务与实验1类似,刺激-反应延迟为0或10秒。两个实验的结果表明,将刺激-反应延迟增加到10秒不会损害声音定位。参与者通过将他们的反应要么朝着与右耳对齐的90度坐标,要么朝着与左耳对齐的270度坐标移动,系统地高估了听觉刺激的偏心率。这种偏差在前后方位空间中是类似的,并且仅受到延迟条件的轻微影响。我们得出结论,工作记忆中听觉空间的表征是稳定的,但存在方向性偏差,对偏心率有系统性的高估。