Hölig Cordula, Föcker Julia, Best Anna, Röder Brigitte, Büchel Christian
Biological Psychology and Neuropsychology, University of Hamburg, Hamburg, Germany; Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
Department of Psychology and Educational Sciences, University of Geneva, Geneva, Switzerland.
Neuroimage. 2014 Dec;103:374-382. doi: 10.1016/j.neuroimage.2014.09.050. Epub 2014 Oct 2.
Blind individuals are trained in identifying other people through voices. In congenitally blind adults the anterior fusiform gyrus has been shown to be active during voice recognition. Such crossmodal changes have been associated with a superiority of blind adults in voice perception. The key question of the present functional magnetic resonance imaging (fMRI) study was whether visual deprivation that occurs in adulthood is followed by similar adaptive changes of the voice identification system. Late blind individuals and matched sighted participants were tested in a priming paradigm, in which two voice stimuli were subsequently presented. The prime (S1) and the target (S2) were either from the same speaker (person-congruent voices) or from two different speakers (person-incongruent voices). Participants had to classify the S2 as either coming from an old or a young person. Only in late blind but not in matched sighted controls, the activation in the anterior fusiform gyrus was modulated by voice identity: late blind volunteers showed an increase of the BOLD signal in response to person-incongruent compared with person-congruent trials. These results suggest that the fusiform gyrus adapts to input of a new modality even in the mature brain and thus demonstrate an adult type of crossmodal plasticity.
盲人接受通过声音识别他人的训练。在先天性失明的成年人中，已显示前梭状回在语音识别过程中会被激活。这种跨模态变化与成年盲人在语音感知方面的优势有关。本功能磁共振成像（fMRI）研究的关键问题是，成年期出现的视觉剥夺是否会伴随着语音识别系统的类似适应性变化。对晚期失明个体和相匹配的视力正常参与者进行了启动范式测试，其中随后呈现两个语音刺激。启动刺激（S1）和目标刺激（S2）要么来自同一个说话者（人物一致的声音），要么来自两个不同的说话者（人物不一致的声音）。参与者必须将S2分类为来自年轻人还是老年人。只有在晚期失明者中，而不是在相匹配的视力正常对照组中，前梭状回的激活受到语音身份的调节：与人物一致的试验相比，晚期失明志愿者在人物不一致的试验中表现出BOLD信号增加。这些结果表明，即使在成熟大脑中，梭状回也能适应新模态的输入，从而证明了一种成人类型的跨模态可塑性。
