Local field potentials in the parietal reach region reveal mechanisms of bimanual coordination

Eric Mooshagian,Charles D Holmes,Lawrence H Snyder

doi:10.1038/s41467-021-22701-3

Eric Mooshagian, Charles D Holmes + Show 1 more

Open Access

https://doi.org/10.1038/s41467-021-22701-3

Copy DOI

Abstract

Primates use their arms in complex ways that frequently require coordination between the two arms. Yet the planning of bimanual movements has not been well-studied. We recorded spikes and local field potentials (LFP) from the parietal reach region (PRR) in both hemispheres simultaneously while monkeys planned and executed unimanual and bimanual reaches. From analyses of interhemispheric LFP-LFP and spike-LFP coherence, we found that task-specific information is shared across hemispheres in a frequency-specific manner. This shared information could arise from common input or from direct communication. The population average unit activity in PRR, representing PRR output, encodes only planned contralateral arm movements while beta-band LFP power, a putative PRR input, reflects the pattern of planned bimanual movement. A parsimonious interpretation of these data is that PRR integrates information about the movement of the left and right limbs, perhaps in service of bimanual coordination.

Highlights

Primates use their arms in complex ways that frequently require coordination between the two arms
Our findings support the hypothesis that the task-specific changes observed in beta-band local field potentials (LFP) (PRR input) are driven, in part, by spikes (PRR output) from the opposite hemisphere
There is a reliable relationship between spikes in one hemisphere and LFP in the other (Fig. 5c), consistent with direct communication between the left and right parietal reach region (PRR)

Summary

Introduction

Primates use their arms in complex ways that frequently require coordination between the two arms. We recorded spikes and local field potentials (LFP) from the parietal reach region (PRR) in both hemispheres simultaneously while monkeys planned and executed unimanual and bimanual reaches. The population average unit activity in PRR, representing PRR output, encodes only planned contralateral arm movements while beta-band LFP power, a putative PRR input, reflects the pattern of planned bimanual movement. Since spiking activity does not contain ipsimanual arm information, but beta-band LFP power does, we suggest that this information originates from PRR in the opposite hemisphere. This is supported by our finding of interhemispheric spike-LFP coherence in the beta band that, like LFP–LFP coherence, is modulated by the type of reach being planned. Our results suggest that bimanual reach planning is achieved in part by the interhemispheric transfer of information at the level of the parietal cortex

Methods

Results

Conclusion