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bioRxiv · 10.1101/2023.09.11.556575

Rat movements reflect internal decision dynamics in an evidence accumulation task.

Abstract

Perceptual decision-making involves multiple cognitive processes, including accumulation of sensory evidence, planning, and executing a motor action. How these processes are intertwined is unclear; some models assume that decision-related processes precede motor execution, whereas others propose that movements reflecting on-going decision processes occur before commitment to a choice. Here we develop and apply two complementary methods to study the relationship between decision processes and the movements leading up to a choice. The first is a free response pulse-based evidence accumulation task, in which stimuli continue until choice is reported. The second is a motion-based drift diffusion model (mDDM), in which movement variables from video pose estimation constrain decision parameters on a trial-by-trial basis. We find the mDDM provides a better model fit to rats decisions in the free response accumulation task than traditional DDM models. Interestingly, on each trial we observed a period of time, prior to choice, that was characterized by head immobility. The length of this period was positively correlated with the rats decision bounds and stimuli presented during this period had the greatest impact on choice. Together these results support a model in which internal decision dynamics are reflected in movements and demonstrate that inclusion of movement parameters improves the performance of diffusion-to-bound decision models. HighlightsO_LIDevelopment and validation of a free response pulse-based accumulation task for rats C_LIO_LIResponse times are well described by drift diffusion models C_LIO_LIIncorporating movement data into diffusion models improves inference of latent decisions variables C_LIO_LIRats weight sensory evidence most strongly prior to movement C_LI

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BibTeXRIS

Kane, G. E., Senne, R. A., Scott, B. B.. 2023-09-13. Rat movements reflect internal decision dynamics in an evidence accumulation task.. https://doi.org/10.1101/2023.09.11.556575

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