A versatile robotic platform for the design of natural, three-dimensional reaching and grasping tasks in monkeys

Abstract

Objective. Translational studies on motor control and neurological disorders require detailed monitoring of sensorimotor components of natural limb movements in relevant animal models. However, available experimental tools do not provide a sufficiently rich repertoire of behavioral signals. Here, we developed a robotic platform that enables the monitoring of kinematics, interaction forces, and neurophysiological signals during user-defined upper limb tasks for monkeys. Approach. We configured the platform to position instrumented objects in a three-dimensional workspace and provide an interactive dynamic force-field. Main results. We show the relevance of our platform for fundamental and translational studies with three example applications. First, we study the kinematics of natural grasp in response to variable interaction forces. We then show simultaneous and independent encoding of kinematic and forces in single unit intra-cortical recordings from sensorimotor cortical areas. Lastly, we demonstrate the relevance of our platform to develop clinically relevant brain computer interfaces in a kinematically unconstrained motor task. Significance. Our versatile control structure does not depend on the specific robotic arm used and allows for the design and implementation of a variety of tasks that can support both fundamental and translational studies of motor control.

Epidural Electrical Stimulation of the Cervical Dorsal Roots Restores Voluntary Upper Limb Control in Paralyzed Monkeys

“…The arrays implantation was achieved using a pneumatic compressor system (Impactor System, Blackrock Microsystems). A pedestal ( Pedestal A ) was then fixated to a compliant titanium mesh (Medtronic Ti-Mesh) modelled to fit the skull shape and implanted in a previous surgery a few weeks earlier 27 .…”

“…Clinically effective systems should demonstrate the ability to enable truly functional arm movements rather than simplified tasks such as single-joint movements. Consequently, we developed a robotic platform allowing the quantification of reach and grasp movements 27 that would feel natural and unconstrained to monkeys. We trained three Macaca fascicularis monkeys to reach for, grasp, and pull an instrumented object placed on the end effector of a robotic arm ( Figure 1 ).…”

Motor cortical dynamics are shaped by multiple distinct subspaces during naturalistic behavior

“…To test our hypothesis, we simultaneously recorded the activity of neural populations from motor and somatosensory cortex of four monkeys as they reached for and interacted with objects 26 . Using trajectory tangling 17 , we showed that the neural population dynamics substantially differed between the two cortical regions.…”

Spatiotemporal Maps of Proprioceptive Inputs to the Cervical Spinal Cord During Three-Dimensional Reaching and Grasping

“…Two females Macaca Fascicularis (Mk-Sa, age 7 years, weight 4 kg and Mk-Br, age 4 years, weight 3.5 kg) were trained to reach with the left arm for a spherical object, grasp it, and pull it towards a return position to receive a food reward [41]. Animals were housed within a group of five animals at the University of Fribourg, Switzerland.…”