모국어 말소리 대조 시 작업기억과 변별능력 간의 연관성

Objectives: Large individual variability is documented for identification performance of native phones, especially in challenging situations. It is not known whether the ability to utilize cues available for phone identification is facilitated by cognitive abilities, thereby explaining a proportion of the individual variability. This study investigated the relationship between working memory capacity and identification of a few Malayalam phones in the absence of contextual cues among native listeners. Methods: Forty native listeners of Malayalam, aged between 18 and 25, participated in this study. Participants identified 8 Malayalam phones embedded in nonsense words. Working memory capacity was measured using tasks such as reading span, operation span, digit forward span, and digit backward span. Identification score for each phone, total phone identification score (average identification score from 8 phones), and reaction time during identification were obtained. Results: Phone identification score of participants ranged from 57.8% to 99%. Pearson product moment correlation analysis showed a significant positive correlation between all measures of working memory capacity and total phone identification score, indicating that working memory capacity play a role in the identification of phones. Reaction time showed a significant negative correlation with digit backward span and operation span. The measures of working memory capacity accounted for 24.7% of the variability in phone identification score. Conclusion: Identification of phones in the absence of contextual cues increases the cognitive load. Therefore, higher working memory capacity might aid in native phone identification in difficult situations. This study reveals the top down influence of cognition on native speech perception.