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Cornil, A.

Publications and source records attributed to Cornil, A..

2 recordsLinked to original sources

Complementary coding of behaviors in striatal pathways supports a dual selection-suppression function

The basal ganglia are known to control actions and modulate movements. Neuronal activity in the two efferent pathways of the dorsal striatum, a major input to the basal ganglia, is critical for appropriate behavioral control. Previous evidence has led to divergent conclusions on the respective engagement of both pathways during actions. We used calcium imaging to evaluate how neurons in the direct and indirect pathways in the dorsal striatum encode behaviors during self-paced spontaneous explorations in an open field. We observed that the two striatal pathways exhibit distinct tuning properties during spontaneous behaviors. We applied supervised learning algorithms and found that direct pathway neurons encode behaviors through their activation, whereas indirect pathway neurons exhibit behavior-specific silencing. These properties remain stable for weeks. Our findings highlight a complementary encoding of behaviors in the two striatal pathways that supports an updated model, reconciling previous conflicting conclusions on motor encoding in the striatum.

neuroscience↗

Unexpected inhibition of motor function by dopamine activation of D1/D2 co-expressing striatal neurons.

The central function of the striatum and its dopaminergic (DA) afferents in motor control and the integration of cognitive and emotional processes is commonly explained by the two striatal efferent pathways characterized by striatal projection neurons (SPNs) expressing DA D1 receptors and D2 receptors (D1-SPNs and D2-SPNs), without regard to SPNs coexpressing both receptors (D1/D2-SPNs). We developed an approach that enables the targeting of these hybrid SPNs and demonstrated that although these SPNs are less abundant, they play a major role in guiding the motor function of the other two main populations. D1/D2-SPNs project exclusively to the external globus pallidus (GPe) and have specific electrophysiological features with distinctive integration of DA signals. Optogenetic stimulation and loss-of-function experiments indicated that D1/D2-SPNs potentiate the prokinetic and antikinetic functions of D1-SPNs and D2-SPNs, respectively, and restrain the integrated motor response to psychostimulants. Overall, our findings demonstrate the essential role of this third unacknowledged population of D1/D2 coexpressing neurons, which orchestrates the fine-tuning of DA regulation in the thalamo-cortico-striatal loops. One-Sentence SummaryD1/D2 SPNs modulate the motor function of both D1- and D2-SPNs

neuroscience↗