Service de Neuropsychologie et de Neuroréhabilitation, Département des Neurosciences cliniques, CHUV, Universtité de Lausanne, Switzerland.
Neuropsychologia. 2011 Jul;49(9):2794-7. doi: 10.1016/j.neuropsychologia.2011.05.024. Epub 2011 Jun 6.
Auditory spatial functions, including the ability to discriminate between the positions of nearby sound sources, are subserved by a large temporo-parieto-frontal network. With the aim of determining whether and when the parietal contribution is critical for auditory spatial discrimination, we applied single pulse transcranial magnetic stimulation on the right parietal cortex 20, 80, 90 and 150 ms post-stimulus onset while participants completed a two-alternative forced choice auditory spatial discrimination task in the left or right hemispace. Our results reveal that transient TMS disruption of right parietal activity impairs spatial discrimination when applied at 20 ms post-stimulus onset for sounds presented in the left (controlateral) hemispace and at 80 ms for sounds presented in the right hemispace. We interpret our finding in terms of a critical role for controlateral temporo-parietal cortices over initial stages of the building-up of auditory spatial representation and for a right hemispheric specialization in integrating the whole auditory space over subsequent, higher-order processing stages.
听觉空间功能，包括辨别近源声音位置的能力，由一个大型颞顶额网络提供支持。为了确定顶叶的贡献是否以及何时对听觉空间辨别至关重要，我们在刺激后 20、80、90 和 150 毫秒应用单脉冲经颅磁刺激右侧顶叶皮层，同时参与者在左或右半空间完成了二选一的强制选择听觉空间辨别任务。我们的结果表明，当在刺激后 20 毫秒应用于左（对侧）半空间呈现的声音时，以及在刺激后 80 毫秒应用于右半空间呈现的声音时，右侧顶叶活动的短暂 TMS 干扰会损害空间辨别。我们根据以下假设来解释我们的发现：在听觉空间表示建立的初始阶段，对侧颞顶皮层起着关键作用，而在随后的更高阶处理阶段，右半球专门用于整合整个听觉空间。
