Development of Korean Staggered Spondaic Word Test

Abstract

Dichotic listening refers to ability to integrate or separate different auditory stimuli presented in each ear simultaneously. Dichotic listening tests have been shown to be sensitive to lesions in hemisphere, interhemisphere and brainstem. Staggered Spondaic Word (SSW) test is the most frequently used dichotic listening test, which consists of spondaic words presented in a partially overlapped manner. The purpose of this study was to develop a Korean version of SSW (K-SSW) test that is equivalent to the English-version test. The test items of 40 pairs of two-syllabic words with 160 monosyllabic words were selected based on the SSW criteria and produced into an audio compact disc in EC manner. These test items were proven by the frequency use of the phonemes, acoustical analysis of the alignment of competing syllables, analysis of the degree of the difficulty, and the similarity of the present conditions. Twenty young adult listeners (aged 20-28 years) with normal hearing sensitivity and central auditory processing were evaluated on the K-SSW test. The results revealed that average total number of errors (TNOE) were 2.95(±1.73), and the 4 competing and non-competing conditions (RC, LC, RNC, LNC) scored 0.2(±0.4), 0.1(±0.3), 0.5(±0.7), and 1.1(±1.2), respectively, showing significant differences among conditions. Performance in the competing conditions was significantly reduced comparing to those in the non-competing conditions. However, there were no significant differences between ears. The subjects' response biases that include ear effect, order effects, and reversals were 0.2(±0.5), -0.6(±1.2), and 0.5(±1.3), respectively. Only three reversals were observed for three listeners. The results indicate that young listeners with normal central auditory functions made few errors with small variability on K-SSW test. The test-retest reliability and the split-form reliability were verified by the significant correlations. The K-SSW test can be usefully applied for the evaluation of central auditory processing in various Korean populations through further verification of the test.