TMS-induced theta phase synchrony reveals a bottom-up network in working memory

Eri Miyauchi; Keiichi Kitajo; Masahiro Kawasaki

doi:10.1016/j.neulet.2016.04.008

TMS-induced theta phase synchrony reveals a bottom-up network in working memory

Neurosci Lett. 2016 May 27:622:10-4. doi: 10.1016/j.neulet.2016.04.008. Epub 2016 Apr 7.

Authors

Eri Miyauchi¹, Keiichi Kitajo², Masahiro Kawasaki³

Affiliations

¹ Department of Intelligent Interaction Technology, Graduate School of Systems and Information Engineering, University of Tsukuba, Japan.
² Rhythm-based Brain Information Processing Unit, RIKEN BSI-TOYOTA Collaboration Center, RIKEN Brain Science Institute, Japan; Laboratory for Advanced Brain Signal Processing, RIKEN Brain Science Institute, Japan.
³ Department of Intelligent Interaction Technology, Graduate School of Systems and Information Engineering, University of Tsukuba, Japan; Rhythm-based Brain Information Processing Unit, RIKEN BSI-TOYOTA Collaboration Center, RIKEN Brain Science Institute, Japan; Laboratory for Advanced Brain Signal Processing, RIKEN Brain Science Institute, Japan. Electronic address: kawasaki@iit.tsukuba.ac.jp.

PMID: 27063284
DOI: 10.1016/j.neulet.2016.04.008

Abstract

Global theta phase synchronization between the frontal and sensory areas has been suggested to connect the relevant areas for executive processes of working memory (WM). However, little is known regarding network directionality (i.e. top-down or bottom-up) of this interaction. To address the issue, the present study conducted transcranial magnetic stimulation (TMS)-electroencephalography (EEG) experiment during WM tasks. Results showed that TMS-induced increases in theta phase synchronization were observed only when TMS was delivered to the sensory areas but not the frontal area. These findings suggest that network directionality represented in WM is bottom-up rather than top-down.

Keywords: EEG; Synchronization; TMS; Theta; Working memory.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Acoustic Stimulation
Adult
Electroencephalography Phase Synchronization
Female
Humans
Male
Memory, Short-Term / physiology*
Photic Stimulation
Theta Rhythm
Transcranial Magnetic Stimulation
Young Adult