Vision Science Program, University of California, Berkeley 94720-2020, USA.
Psychol Sci. 2013 Aug;24(8):1389-97. doi: 10.1177/0956797612473759. Epub 2013 Jun 12.
In vision, humans use summary statistics (e.g., the average facial expression of a crowd) to efficiently perceive the gist of groups of features. Here, we present direct evidence that ensemble coding is also important for auditory processing. We found that listeners could accurately estimate the mean frequency of a set of logarithmically spaced pure tones presented in a temporal sequence (Experiment 1). Their performance was severely reduced when only a subset of tones from a given sequence was presented (Experiment 2), which demonstrates that ensemble coding is based on a substantial number of the tones in a sequence. This precise ensemble coding occurred despite very limited representation of individual tones from the sequence: Listeners were poor at identifying specific individual member tones (Experiment 3) and at determining their positions in the sequence (Experiment 4). Together, these results indicate that summary statistical coding is not limited to visual processing and is an important auditory mechanism for extracting ensemble frequency information from sequences of sounds.
在视觉中，人类使用摘要统计信息（例如，人群的平均面部表情）来有效地感知特征群的要点。在这里，我们提供了直接的证据，表明集合编码对于听觉处理也很重要。我们发现，听众可以准确估计一组以对数间隔呈现的纯音的平均频率（实验 1）。当仅呈现给定序列中的一部分音时，他们的表现会严重下降（实验 2），这表明集合编码基于序列中的大量音。尽管对序列中个别音的表示非常有限，但这种精确的集合编码仍然存在：听众很难识别特定的个别成员音（实验 3），也很难确定它们在序列中的位置（实验 4）。这些结果表明，摘要统计编码不仅限于视觉处理，而是从声音序列中提取集合频率信息的重要听觉机制。
