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bioRxiv · 10.1101/2023.07.17.549313

Dopaminergic manipulations affect the modulation and meta-modulation of movement speed: evidence from two pharmacological interventions

Hickman, L. J.·Sowden, S. L.·Fraser, D. S.·Schuster, B. A.·Rybicki, A. J.·Galea, J. M.·Cook, J. L.
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Abstract

A body of research implicates dopamine in the average speed of simple movements. However, naturalistic movements span a range of different shaped trajectories and rarely proceed at a single constant speed; instead, speed is reduced when drawing "corners" compared to "straights" (i.e., speed-modulation), and the extent of this slowing down is dependent upon the global shape of the movement trajectory (i.e., speed-meta-modulation) - for example whether the shape is an ellipse or a rounded square. By employing two pharmacological intervention studies - individuals with Parkinsons both ON and OFF dopaminergic medication (N = 32) and members of the general population on a D2 receptor blocker (haloperidol) versus placebo (N = 43) - we implicate dopamine in speed, speed-modulation and speed-meta-modulation. Our findings move beyond vigour models implicating dopamine in average movement speed, and towards a conceptualisation that involves the modulation of speed as a function of contextual information.

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Hickman, L. J., Sowden, S. L., Fraser, D. S., Schuster, B. A., Rybicki, A. J., Galea, J. M., Cook, J. L.. 2023-07-21. Dopaminergic manipulations affect the modulation and meta-modulation of movement speed: evidence from two pharmacological interventions. https://doi.org/10.1101/2023.07.17.549313

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