Hasson Uri, Skipper Jeremy I, Nusbaum Howard C, Small Steven L
Department of Neurology, The University of Chicago, Chicago, IL 60637, USA.
Neuron. 2007 Dec 20;56(6):1116-26. doi: 10.1016/j.neuron.2007.09.037.
Is there a neural representation of speech that transcends its sensory properties? Using fMRI, we investigated whether there are brain areas where neural activity during observation of sublexical audiovisual input corresponds to a listener's speech percept (what is "heard") independent of the sensory properties of the input. A target audiovisual stimulus was preceded by stimuli that (1) shared the target's auditory features (auditory overlap), (2) shared the target's visual features (visual overlap), or (3) shared neither the target's auditory or visual features but were perceived as the target (perceptual overlap). In two left-hemisphere regions (pars opercularis, planum polare), the target invoked less activity when it was preceded by the perceptually overlapping stimulus than when preceded by stimuli that shared one of its sensory components. This pattern of neural facilitation indicates that these regions code sublexical speech at an abstract level corresponding to that of the speech percept.
是否存在一种超越语音感官属性的神经表征？我们使用功能磁共振成像（fMRI）来研究，在观察次词汇视听输入时，大脑中是否存在这样的区域，即其中的神经活动对应于听者的言语感知（即“听到的内容”），而与输入的感官属性无关。在目标视听刺激之前呈现的刺激分别为：（1）与目标具有相同听觉特征的刺激（听觉重叠），（2）与目标具有相同视觉特征的刺激（视觉重叠），或（3）既不与目标具有相同听觉特征也不具有相同视觉特征但被感知为目标的刺激（感知重叠）。在左半球的两个区域（岛盖部、颞极平面），与具有一种感官成分重叠的刺激相比，当目标刺激之前呈现感知重叠刺激时，目标引发的活动更少。这种神经易化模式表明，这些区域在与言语感知相对应的抽象水平上对次词汇语音进行编码。
