Fig. 2A: Somatotopic cerebellar activations evoked by optogenetic intracortical microstimulation of the primary motor cortex (monkey C)

Fig. 2B: Somatotopic cerebellar activations evoked by optogenetic intracortical microstimulation of the primary motor cortex (monkey N)

Fig. 3AB: Cerebral Cortex: Summary

Fig. 4A: Regions of Interest

Supplementary Fig. 1A: tSNR map

Supplementary Fig. 1B: Effect of light pulse parameters on fMRI activity

Supplementary Fig. 5AC: Results of control fMRI experiments

Figs_Goda_et_al_OptofMRINHP.scene

FULL TITLE:
Cerebro-cerebellar interactions in non-human primates examined by optogenetic functional magnetic resonance imaging

SPECIES:
Macaque

ABSTRACT:
Functional magnetic resonance imaging (fMRI) is a promising approach for simultaneous and extensive scanning of whole-brain activities. Optogenetics is free from electrical and magnetic artifacts and is an ideal stimulation method for combined use with fMRI. However, the application of optogenetics in non-human primates remains limited. Recently, we developed an efficient optogenetic intracortical microstimulation method of the primary motor cortex (M1), which successfully induced forelimb movements in macaque monkeys. Here, we aimed to investigate how optogenetic M1 stimulation causes neural modulation in the local and remote brain regions in anesthetized monkeys using 7-tesla fMRI. We demonstrated that optogenetic stimulation of the M1 forelimb and hindlimb regions successfully evoked robust direct and remote fMRI activities. Prominent remote activities were detected in the anterior and posterior lobes in the contralateral cerebellum, which receives projections polysynaptically from the M1. We further demonstrated that the cerebro-cerebellar projections from these M1 regions were topographically organized, concordant with the somatotopic map in the cerebellar cortex previously reported in macaques and humans. The present study significantly enhances optogenetic fMRI (opto-fMRI) in non-human primates resulting in profound understanding of the brain network thereby accelerating the translation of findings from animal models to humans.

PUBLICATION:
Cerebral Cortex Communications - DOI: 10.1093/texcom/tgac022