Department of Psychiatry, Boston Children's Hospital, Boston, Massachusetts 02115, USA.
Department of Electrical and Computer Engineering, University of Massachusetts Dartmouth, Dartmouth, Massachusetts 02747, USA.
J Acoust Soc Am. 2020 Jan;147(1):371. doi: 10.1121/10.0000584.
Perceptual anchors are representations of stimulus features stored in long-term memory rather than short-term memory. The present study investigated whether listeners use perceptual anchors to improve pure-tone frequency discrimination. Ten amateur musicians performed a two-interval, two-alternative forced-choice frequency-discrimination experiment. In one half of the experiment, the frequency of the first tone was fixed across trials, and in the other half, the frequency of the first tone was roved widely across trials. The durations of the interstimulus intervals (ISIs) and the frequency differences between the tones on each trial were also manipulated. The data were analyzed with a Bayesian model that assumed that performance was limited by sensory noise (related to the initial encoding of the stimuli), memory noise (which increased proportionally to the ISI), fluctuations in attention, and response bias. It was hypothesized that memory-noise variance increased more rapidly during roved-frequency discrimination than fixed-frequency discrimination because listeners used perceptual anchors in the latter condition. The results supported this hypothesis. The results also suggested that listeners experienced more lapses in attention during roved-frequency discrimination.
感知锚点是存储在长期记忆中而不是短期记忆中的刺激特征的表示。本研究调查了听众是否使用感知锚点来提高纯音频率辨别力。十名业余音乐家进行了两次间隔、两种选择的强制选择频率辨别实验。在实验的一半中，第一音的频率在试验中是固定的，而在另一半中，第一音的频率在试验中广泛地漫游。刺激间隔（ISIs）的持续时间和每个试验中两个音之间的频率差也被操纵。数据使用一个贝叶斯模型进行分析，该模型假设性能受到感官噪声（与刺激的初始编码有关）、记忆噪声（与 ISI 成比例增加）、注意力波动和响应偏差的限制。假设在漫游频率辨别中，记忆噪声方差的增加速度比固定频率辨别中更快，因为听众在后一种情况下使用感知锚点。结果支持了这一假设。结果还表明，在漫游频率辨别中，听众的注意力更容易出现失误。
