通过功能性磁共振成像技术考察了额下回眶部(BA47)在言语中的音高和时长信息加工中的作用,发现音高和时长信息的加工在该脑区存在着明显的分离,这种分离可能是听觉加工腹侧通路的重要组成部分,即左脑和右脑颞叶的听觉和听觉相关皮层分别负责音高和时长信息的声学特征分析,而对应的额下回腹侧眶部则分别负责相关信息在工作记忆中的表征和保持,研究结果为音高和时长信息加工的声音信号假设提供了更为全面的证据。
Using fMRI, we explored the role of the ventral prefrontal cortex (BA47) in the processing of pitch and duration information in speech and found that the processing of pitch and duration information was dissociated in this brain area, i.e. the left side was sensitive to duration variation, while the right side was sensitive to pitch patterns. The dissociation in BA47 was similar to that in the auditory cortex reported before. The auditory cortex and BA47 that constitute the ventral auditory pathway played different roles in auditory processing, that is, the auditory cortex was involved in the perceptual analysis of signals and BA47 was involved in maintaining information in working memory. The results indicate that the processing of pitch and duration is dissociated at the stages of both signal analysis and short-term maintenance of information, providing further support for the acoustic cue hypothesis.