Hirano S, Naito Y, Okazawa H, Kojima H, Honjo I, Ishizu K, Yenokura Y, Nagahama Y, Fukuyama H, Konishi J
Department of Hearing and Speech Science, Faculty of Medicine, Kyoto University, Japan.
Exp Brain Res. 1997 Jan;113(1):75-80. doi: 10.1007/BF02454143.
To investigate how auditory input from each ear contributes to spoken language processing, cortical activation by monaural speech sound stimulation was examined in 12 normal subjects using 15O-labeled water positron emission tomography. Regional cerebral blood flow (rCBF) was measured under four different sound stimulation conditions: (1) silence, (2) white noise, (3) sequential Japanese sentences ("speech"), and (4) Japanese sentences played backward ("reversed speech"), and the results were evaluated by statistical parametric mapping (SPM). Noise induced significant rCBF increase in the contralateral Heschl's gyrus. Speech and reversed speech stimuli caused significant rCBF increase in the contralateral Heschl's gyrus and the bilateral superior temporal gyri, with contralateral activation broader than that in the ipsilateral hemisphere. Monaurally input speech sound signals that reach the contralateral Heschl's gyrus may be processed chiefly and phonologically in the surrounding superior temporal gyrus in the same hemisphere. Comparison of speech activation with reversed speech activation failed to demonstrate a significant difference, which made it difficult to identify the area for lexical and semantic processing.
为研究每只耳朵的听觉输入如何促进口语加工，使用15O标记水正电子发射断层扫描技术，对12名正常受试者进行单耳语音刺激的皮质激活情况检测。在四种不同声音刺激条件下测量局部脑血流量（rCBF）：（1）安静，（2）白噪声，（3）连续的日语句子（“语音”），（4）倒放的日语句子（“倒序语音”），并通过统计参数映射（SPM）评估结果。噪声引起对侧颞横回rCBF显著增加。语音和倒序语音刺激导致对侧颞横回和双侧颞上回rCBF显著增加，对侧激活范围比同侧半球更广泛。到达对侧颞横回的单耳输入语音信号可能主要在同一半球周围的颞上回进行语音处理。语音激活与倒序语音激活的比较未显示出显著差异，这使得难以确定词汇和语义处理区域。
