Sparse and specific somatosensory functional innervation of dorsolateral striatal neurons

Kenza Amroune (1) , Lorenzo Fontolan (1, 2) , David Robbe (1, 2) , Ingrid Bureau (1)

1 INMED - INSERM U1249 - Institut de Neurobiologie de la Méditerranée [Aix-Marseille Université]
2 TCLS - Turing Centre for Living Systems [Marseille]

The dorsal striatum receives dense and overlapping cortical projections making it an important structure for sensory integration. However, the degree of input convergence to individual striatal projection neurons (SPNs) is unclear. To address this issue, we investigated convergence in the vibrissal corticostriatal projection using an ex vivo functional approach combining laser scanning photostimulation in the mouse barrel cortex with patch-clamp recordings in the dorsolateral striatum. We found that the functional innervation of individual SPNs is sparse and specific to each cell, suggesting that sensory integration occurs at the population level. However, patterns with different degrees of input convergence were observed. Interestingly, they are associated with intrinsic behavioral biases of mice placed in an open field: preference for contralateral tactile input for direct pathway SPNs and locomotion speed for indirect pathway SPNs. Altogether, these results suggest that corticostriatal connections are selectively formed, constraining the convergence of vibrissal input to each SPN and generating innervation patterns that reflect individual biases in tactile behavior.

Mots clés: Corticostriatal projection; barrel cortex; functional mapping; connectivity

Domaines: Neurosciences; Neurobiologie

Kenza Amroune, Lorenzo Fontolan, David Robbe, Ingrid Bureau. Sparse and specific somatosensory functional innervation of dorsolateral striatal neurons. 2024. ⟨hal-04567026⟩