本研究的目的是探討雙耳異訊測驗材料(數字、句子與疊詞)與年齡群(年輕與年長)在耳朵優勢的效應,以及此效應是否是另一耳的劣勢造成。受試者是29名年輕者與20名年長者,除了年長組的右耳8,000Hz之外,聽力都正常。(一)跨耳比較:右耳優勢有年齡與測驗材料效應(出現在年長組的句子與疊詞測驗),年長組從非競訊轉為競訊時,得分下降幅度左耳大於右耳(稱為左耳劣勢),這是造成右耳優勢的主因。95%的年長組個案有左耳 劣勢,但左耳得分下降幅度的個別差異很大;(二)跨年齡組比較:數字、句子與疊詞測驗都是年輕組表現較佳(左右耳皆如此),疊詞右耳例外(兩組相近);(三)右耳優勢人數:疊詞測驗多於句子測驗;顯然以疊詞測驗觀察年長者的左耳劣勢有其優勢。
The purpose of this study was to investigate the effects of test material and age on participants' listening performance in dichotic tests. A younger group (YG) consisting of 29 people and an elderly group (EG) consisting of 20 people participated in the study. A Mandarin dichotic digit (DDI-M) test, Mandarin dichotic sentence identification (DSI-M) test, and Mandarin staggered spondaic (SSW-M) test were administered. Aside from the thresholds at 8,000 Hz in the right ears of the participants in the EG, the participants' hearing abilities were within normal limits. Results showed the following: Right ear advantage (REA) was revealed in the DDI-M test results of the YG, as well as in the DSI-M and SSW-M test results of the EG. The decline of the scores from a noncompeting to a competing condition is referred to as ear disadvantage. The left ear disadvantage (LED) was greater than that in the right ear in the EG. LED seemed to be the major contributor to REA. LED was observed in 95% of the EG participants; however, the individual differences were great. The observed group differences included the following: the YG scored higher than the EG did in the DDI-M, DSI-M, and SSW-M tests, except for the right competing condition observed in the SSW-M test results. The participants who exhibited the REA phenomenon in the SSW-M outnumbered those who did in the DSI-M test. The advantage of administering the SSW-M test was revealing LED.