Biology subjects

Poitreau, J.

Publications and source records attributed to Poitreau, J..

4 recordsLinked to original sources

bioRxiv2024

Dorsal striatum involvement in response conflict management - A lesion study in rats

Action control allows to respond to relevant stimuli while ignoring the non-relevant stimuli in the surrounding environment. In humans this process is generally studied in conflict tasks, such as the Simon task, in which participants respond with a left or right button press to the non-spatial relevant feature (e.g. the color) of a lateralized stimulus, while ignoring the stimulus position. In this study we used a visual version of the Simon task that we have previsously developed in rats to investigate the involvement of the dorsal striatum, a brain area that is central in action control processes. We tested the effect of excitotoxic lesions of the dorsomedial (DMS) and dorsolateral (DLS) areas in learning to control response interference. We showed that both DMS and DLS lesions negatively impacted rat performances, and this effect strongly depends on task practice. These results suggest an involvement of both areas in learning to manage response conflict.

neuroscience↗

bioRxiv2024

At the roots of interference control: Conflict task in rats reveals the commonalities of onto- and phylo-genetic development

Responding to internal goals and filtering irrelevant environmental cues is essential for adapted behavior. To better understand their phylogenetic evolution, we explored the underlying mechanisms in rats, thanks to the adaptation of a well-established conflict task in Humans. Besides mean performance, state of the art data analysis based on distribution analysis and formal modeling (diffusion model adapted to conflict tasks that proved very powerful in Humans) revealed mechanisms similar to the ones observed in human adults, grounding any theoretical explanation into an evolutionary perspective. Besides, the dynamics of the underlying processes in this simple conflict task resembles the ones observed in human children performing a more challenging conflict task, including the tendency to loose goals. The present study bridges the gap between onto- and phylo-genetic development of cognitive control, opening new perspectives to understand both their functional and neural implementation.

animal behavior and cognition↗

bioRxiv2023

Coding dynamics of the striatal networks during learning

The rat dorsomedial (DMS) and dorsolateral striatum (DMS), equivalent to caudate nucleus and putamen in primates, are generally required for goal-directed and habit behaviour, respectively. However, it is still unclear whether and how this functional dychotomy emerges in the course of learning. In this study we investigated this issue by recording DMS and DLS single neuron activity in rats performing a continuous spatial alternation task, from the acquisition to optimized performance. We first applied a classical analytical approach to identify task-related activity based on the modifications of single neuron firing rate in relation to specific task events or maze trajectories. We then used an innovative approach based on Hawkes process to reconstruct a directed connectivity graph of simultaneously recorded neurons, that was used to decode animal behavior. This approach enabled us to better unravel the role of DMS and DLS neural networks across learning stages. We showed that DMS and DLS display different task-related activity throughout learning stages, and the proportion of coding neurons over time decreases in the DMS and increases in the DLS. Despite theses major differences, the decoding power of both networks increases during learning. These results suggest that DMS and DLS neural networks gradually reorganize in different ways in order to progressively increase their control over the behavioral performance.

neuroscience↗

bioRxiv2023

Distinct sources and behavioral correlates of macaque motor cortical low and high beta

HIGHLIGHTSO_LIThe low beta rhythm is dominant in M1 and the high beta rhythm in PMd C_LIO_LIThe beta rhythms correlate with task-instructed and uninstructed behavior C_LIO_LILow beta reflects movement preparation and spontaneous postural dynamics C_LIO_LIHigh beta reflects temporal task prediction and dynamical visuospatial attention C_LI Low and high beta frequency rhythms were observed in the motor cortex, but their respective sources and behavioral correlates remain unknown. We studied local field potentials during pre-cued reaching behavior in macaques. They contained a low beta band (<20Hz) dominant in primary motor cortex and a high beta band (>20Hz) dominant in dorsal premotor cortex. Low beta correlated positively with reaction time from visual cue onset, and negatively with uninstructed hand postural micro-movements throughout the trial. High beta reflected temporal task prediction, with selective modulations before and during cues, which were enhanced in moments of increased focal attention when the gaze was on the work area. This double-dissociation in sources and behavioral correlates of motor cortical low and high beta, with respect to both task-instructed and spontaneous behavior, reconciles the largely disparate roles proposed for the beta rhythm, by suggesting band-specific roles in both movement control and spatio-temporal attention. O_FIG O_LINKSMALLFIG WIDTH=179 HEIGHT=200 SRC="FIGDIR/small/534535v2_ufig1.gif" ALT="Figure 1"> View larger version (48K): org.highwire.dtl.DTLVardef@fdd46aorg.highwire.dtl.DTLVardef@84b620org.highwire.dtl.DTLVardef@d12baaorg.highwire.dtl.DTLVardef@89a757_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗