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Bosz, E.

Publications and source records attributed to Bosz, E..

2 recordsLinked to original sources
bioRxiv2023

A cortico-subcortical loop for motor control via the pontine reticular formation

Movement and locomotion are controlled by large neuronal circuits like the cortex-basal ganglia (BG)-thalamus loop. Inhibitory output of the BG loop can directly control movement via specialized connections with the brainstem. Whether other parallel loops with similar logic exist is presently unclear. Here we demonstrate that glycine transporter 2-positive (GlyT2+) cells of the pontine reticular formation (PRF) receive cortical inputs and in turn innervate the thalamus. Thalamus-projecting GlyT2+ cells innervate subcortical regions distinct from BG targets. Cortical cells co-innervate PRF/GlyT2+ cells and thalamus as in the BG loops. Cortex exerts strong excitatory control on PRF/GlyT2+ cells and these neurons powerfully inhibit their thalamic targets. Activation of thalamus projecting PRF/GlyT2+ cells leads to contralateral turning. These results demonstrate that the PRF is part of a cortico-subcortical loop that regulates motor activity parallel to the BG circuits. The cortico-PRF-thalamus loop can synergistically control turning with the BG loops via distinct descending pathways. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=190 HEIGHT=200 SRC="FIGDIR/small/552594v2_ufig1.gif" ALT="Figure 1"> View larger version (25K): org.highwire.dtl.DTLVardef@fa1ed8org.highwire.dtl.DTLVardef@ff110dorg.highwire.dtl.DTLVardef@1b88ed7org.highwire.dtl.DTLVardef@1aa02a8_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗
bioRxiv2022

Region Selective Cortical Control Of The Thalamic Reticular Nucleus

Corticothalamic pathways, responsible for the top-down control of the thalamus display a classical, canonical organization in that every cortical region sends dual, layer 6 (L6) and layer 5 (L5) output to the thalamus. Here we demonstrate a qualitative, region-specific difference in the organization of corticothalamic pathways. We show that L5 pyramidal cells of the frontal, but not other cortical regions establish monosynaptic connection with the inhibitory thalamic reticular nucleus (TRN). The frontal L5-TRN pathway paralleled the L6-TRN projection but displayed distinct morphological and physiological features. The exact spike output of the L5 contacted TRN cells correlated with the level of cortical synchrony. Optogenetic perturbation of the L5-TRN connection disrupted the tight link between cortical and TRN activity. L5-driven TRN cells innervated all thalamic nuclei involved in the control of frontal cortical activity. Our data show that frontal cortical functions require a highly specialized cortical control over intrathalamic inhibitory processes.

neuroscience↗