Abstract
For working memory (WM), the fontal region is mainly related to executive functions, which is reported to be communicated with task-relevant sensory posterior regions. However it is not clear about an information flow within the networks. Here we conducted simultaneous electroencephalograph (EEG) and transcranial magnetic stimulation (TMS) experiments during auditory WM tasks which required mental calculation of auditory presented numbers and visual WM tasks which required mental spatial manipulation of visual stimulus. These tasks were conducted under single-pulse TMS over frontal, temporal and parietal regions, and sham/no TMS. Performance showed no differences among conditions. EEG time-frequency analyses revealed the frontal theta (6Hz) and temporal and parietal alpha (10Hz) activities during the auditory and visual WM, respectively. These regions revealed modulation of phase synchronization and propagation of TMS-induced phase resetting in a task-relevant way. These results suggested the neural oscillatory dynamics of the frontal and posterior regions for WM manipulation.
