Department of Psychology, Graduate School of Humanities and Sociology, The University of Tokyo, Tokyo, Japan.
Department of Psychology, College of Contemporary Psychology, Rikkyo University, Saitama, Japan.
Psychon Bull Rev. 2020 Aug;27(4):700-706. doi: 10.3758/s13423-020-01732-9.
Synesthesia is a condition in which the perception of a stimulus in one modality automatically triggers a secondary sensation in another modality or processing stream. Our study focused on grapheme-color synesthesia, in which the visual perception of letters or numbers (graphemes) induces a specific color sensation (the synesthetic color). Grapheme-color synesthetes do not typically experience colors for novel graphemes. However, synesthetic colors associated with familiar graphemes can be transferred to graphemes learned later, even in adulthood. A previous study has shown that such a transfer can take place after only a 10-min writing exercise. In this study, we found that this immediate transfer occurs only when the synesthetic colors for familiar graphemes contribute to the discrimination of the graphemes to be learned. Synesthetes learned six novel graphemes, each of which was arbitrarily associated with one of six familiar graphemes. Half of the synesthetes were assigned to the heterogeneous condition, in which the synesthetic colors of one group of familiar graphemes were different from one another. The other half of the synesthetes were assigned to the homogeneous condition, in which the various colors of a whole group of familiar graphemes were categorically the same. After this learning session, less transfer of synesthetic colors to novel graphemes from the corresponding familiar graphemes occurred in the homogeneous condition than in the heterogeneous condition. These results support the view that synesthetic colors for graphemes may function as a grapheme acquisition aid.
联觉是一种状态，其中一种感觉模式的刺激感知会自动触发另一种感觉模式或处理流的二次感觉。我们的研究集中在字母-颜色联觉上，其中字母或数字（字母）的视觉感知会引起特定的颜色感觉（联觉颜色）。字母-颜色联觉者通常不会对新的字母产生颜色。然而，与熟悉的字母相关联的联觉颜色可以转移到以后学习的字母上，即使是在成年后。先前的一项研究表明，这种转移仅在 10 分钟的写作练习后即可发生。在这项研究中，我们发现只有当熟悉的字母的联觉颜色有助于区分要学习的字母时，才会发生这种即时转移。被试学习了六个新的字母，每个字母都与六个熟悉的字母之一任意相关联。一半的被试被分配到异质条件下，其中一组熟悉的字母的联觉颜色彼此不同。另一半被试被分配到同质条件下，其中整组熟悉的字母的各种颜色都是相同的。在这个学习过程之后，从相应的熟悉字母向新字母转移的联觉颜色在同质条件下比在异质条件下要少。这些结果支持了这样一种观点，即字母的联觉颜色可能作为一种字母获取辅助工具发挥作用。
