Understanding diaschisis models of attention dysfunction with rTMS

Javier O Garcia,Lorella Battelli,Emily D Grossman,Zaira Cattaneo,Ela Plow,Jean Vettel

doi:10.1038/s41598-020-71692-6

Abstract

Visual attentive tracking requires a balance of excitation and inhibition across large-scale frontoparietal cortical networks. Using methods borrowed from network science, we characterize the induced changes in network dynamics following low frequency (1 Hz) repetitive transcranial magnetic stimulation (rTMS) as an inhibitory noninvasive brain stimulation protocol delivered over the intraparietal sulcus. When participants engaged in visual tracking, we observed a highly stable network configuration of six distinct communities, each with characteristic properties in node dynamics. Stimulation to parietal cortex had no significant impact on the dynamics of the parietal community, which already exhibited increased flexibility and promiscuity relative to the other communities. The impact of rTMS, however, was apparent distal from the stimulation site in lateral prefrontal cortex. rTMS temporarily induced stronger allegiance within and between nodal motifs (increased recruitment and integration) in dorsolateral and ventrolateral prefrontal cortex, which returned to baseline levels within 15 min. These findings illustrate the distributed nature by which inhibitory rTMS perturbs network communities and is preliminary evidence for downstream cortical interactions when using noninvasive brain stimulation for behavioral augmentations.

Highlights

Visual attentive tracking requires a balance of excitation and inhibition across large-scale frontoparietal cortical networks
This study proceeded as a “condition-and-map” paradigm, in which participants received 15 min of 1 Hz inhibitory active stimulation over the left intraparietal sulcus. repetitive transcranial magnetic stimulation (rTMS) followed immediately, within 5 min, by the initiation of functional magnetic resonant imaging (fMRI)
Inhibitory rTMS over left parietal cortex targets cortical networks that competitive mechanisms that support one’s ability to engage in bilateral visual tracking[20,49,50]

Summary

Introduction

Visual attentive tracking requires a balance of excitation and inhibition across large-scale frontoparietal cortical networks. RTMS temporarily induced stronger allegiance within and between nodal motifs (increased recruitment and integration) in dorsolateral and ventrolateral prefrontal cortex, which returned to baseline levels within 15 min. These findings illustrate the distributed nature by which inhibitory rTMS perturbs network communities and is preliminary evidence for downstream cortical interactions when using noninvasive brain stimulation for behavioral augmentations. Repetitive TMS is a effective tool for modulating large-scale brain networks, including downstream from the stimulation site, by employing a propagation of pulses that travel through functionally connected s ystems[18, 21,22,23,24,25,26]. The extended action of rTMS makes it well-suited for pairing with functional magnetic resonant imaging (fMRI) using a “condition-and-map” approach by which the durable impacts of neuromodulation on the dynamics of functionally connected circuits can be e valuated[31]

Objectives

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Results

Discussion

Conclusion