Institute of Cognitive Neuroscience, Biopsychology, Department of Psychology, Ruhr-University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany.
Cognitive Neurophysiology, Department of Child and Adolescent Psychiatry, Faculty of Medicine, TU Dresden, Fetscherstrasse 74, 01307 Dresden, Germany.
Sci Adv. 2018 Jul 11;4(7):eaar6830. doi: 10.1126/sciadv.aar6830. eCollection 2018 Jul.
The left hemispheric advantage in speech perception is reflected in faster neurophysiological processing. On the basis of postmortem data, it has been suggested that asymmetries in the organization of the intrinsic microcircuitry of the posterior temporal lobe may produce this leftward timing advantage. However, whether this hypothetical structure-function relationship exists in vivo has never been empirically validated. To test this assumption, we used in vivo neurite orientation dispersion and density imaging to quantify microcircuitry in terms of axon and dendrite complexity of the left and right planum temporale in 98 individuals. We found that a higher density of dendrites and axons in the temporal speech area is associated with faster neurophysiological processing of auditory speech, as reflected by electroencephalography. Our results imply that a higher density and higher number of synaptic contacts in the left posterior temporal lobe increase temporal precision and decrease latency of neurophysiological processes in this brain region.
言语感知的左半球优势反映在更快的神经生理处理速度上。基于尸检数据，有人提出，后颞叶内在微电路结构的不对称性可能产生这种左向时间优势。然而，这种假设的结构-功能关系是否存在于体内尚未得到经验验证。为了检验这一假设，我们使用体内神经突取向弥散和密度成像技术，以量化 98 个人的左右颞平面言语区的轴突和树突复杂性的微电路。我们发现，颞叶言语区的树突和轴突密度越高，脑电图反映的听觉言语神经生理处理速度越快。我们的结果表明，左后颞叶中更高密度和更多数量的突触接触增加了该脑区神经生理过程的时间精度并减少了潜伏期。
