ISSN : 1226-9654
색-자소 공감각자들은 글자나 숫자를 볼 때 특정 색을 함께 경험한다. 큰 개인차에도 불구하고 공감각 색의 결정요인을 밝히려는 노력이 계속되어왔다. 예를 들어, 자소의 사용빈도가 공감각 색의 채도와 상관이 있다고 밝힌 연구가 있는가 하면(Beeli et al., 2007), 사용빈도가 파장과 상관을 보인다는 연구도 존재한다(Herman et al. 2013). 본 연구에서는 한국인 다중언어 공감각자를 대상으로 자소의 빈도가 공감각 색의 파장과 색상, 채도, 명도(HSL)와 상관이 있는지 알아보고자 하였다. 또한 빈도와 공감각 색 간의 상관관계가 모국어와 외국어에서 차별적으로 나타나는지 알아보고자 하였다. 7인의 한국인 다중언어 공감각자가 실험에 참여하였다. 이들은 한글 자음과 라틴 알파벳에 대해 경험하는 공감각 색을 모니터 상의 색 팔레트에서 고르는 과제를 수행하였다. 공감각 색의 RGB 값은 CIE xyY 좌표로 치환되었고, 이 좌표를 활용해 주파장과 HSL 값을 추출하였다. 자소 빈도는 표기빈도와 발화빈도 두 가지로 나뉘어 분석에 사용되었다. 주파장을 활용한 분석에서 한글 자음과 라틴 알파벳 모두 표기 및 발화에서 고빈도의 자소가 장파장을 가진 공감각 색을 유발하는 경향을 보였다. 그러나 이러한 경향은 공감각자 개인에게서 라틴 알파벳에 비해 한글 자음에서 더 명확하게 나타났다. 채도와 명도 또한 한글 자음의 빈도와 정적 상관을 보였다. 라틴 알파벳은 색상, 채도, 명도에 있어서 어떠한 유의미한 상관도 보이지 않았다. 언어 간 비교에서 주파장과 빈도 간의 상관은 모국어와 외국어 간에 유의미한 차이가 나타나지 않은 반면, 채도 및 명도는 언어 간 유의미한 차이를 보였다. 본 연구는 경험을 통해 암묵적으로 학습된 자소의 빈도가 공감각 색 경험에 영향을 주고 이 상관이 언어 습득 시기, 유창성 등으로 인해 모국어와 외국어에서 차별적으로 나타날 수 있음을 시사한다. 따라서 본 연구의 결과는 공감각 색 경험이 감각의 문제만이 아니라 언어, 학습, 기억 등 더 넓은 범주의 인지과정과 연합될 가능성을 제시한다.
Individuals with color-graphemic synesthesia experience idiosyncratic colors while viewing achromatic letters or digits. Despite the large individual difference in grapheme-color associations, several studies have tried to examine the determinants of grapheme-color synesthesia. For example, Beeli et al. (2007) found that the more a letter is frequently used in German, the more saturated was the synesthetic color induced by it, and Hermann et al. (2012) found the correlation between grapheme frequency and the wavelength of synesthetic color. In the present study, we investigated whether grapheme occurrence frequency is associated with hue, saturation, luminance (HSL) and dominant wavelength of induced synesthetic color. We also investigated whether the potential correlation between grapheme frequency and synesthetic color differs between the first and the second languages. Seven Korean multilingual synesthetes participated in a color-matching test where they picked their “colors” from the color palette on the color-calibrated monitor while viewing Korean consonants and Latin alphabets. The matched RGB values of those graphemes were converted into CIE xy coordinates on the CIE xyY color space. HSL value and dominant wavelength were extracted from the CIE xy coordinates. Two kinds of grapheme frequency - written and spoken - were considered. The results showed that graphemes used more frequently within written and spoken language tended to induce synesthetic colors with longer wavelength both for Korean consonants and for Latin alphabets. However, correlation between grapheme frequency and dominant wavelength was stronger for Korean consonants than for Latin alphabets. In terms of HSL, saturation and luminance showed positive correlation with frequency in Korean consonants. No significant correlations were found in Latin alphabets. Difference between Korean consonants and Latin alphabets in terms of saturation was found within written and spoken frequency and difference in terms of luminance was shown within spoken frequency. These results imply that grapheme frequency can shape synesthetic color perception and its’ influence can differ between the first and the second languages. The results from this study, therefore, suggest the possibility that synesthetic color experience is not only related to perception but broader ranges of cognitive processes including language, learning, and memory.
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