Publications by authors named "J Laurens"

People with late-stage Parkinson's disease (PD) often suffer from debilitating locomotor deficits that are resistant to currently available therapies. To alleviate these deficits, we developed a neuroprosthesis operating in closed loop that targets the dorsal root entry zones innervating lumbosacral segments to reproduce the natural spatiotemporal activation of the lumbosacral spinal cord during walking. We first developed this neuroprosthesis in a non-human primate model that replicates locomotor deficits due to PD.

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The Nodulus and Uvula (NU) (lobules X and IX of the cerebellar vermis) form a prominent center of vestibular information processing. Over decades, fundamental and clinical research on the NU has uncovered many aspects of its function. Those include the resolution of a sensory ambiguity inherent to inertial sensors in the inner ear, the otolith organs; the use of gravity signals to sense head rotations; and the differential processing of self-generated and externally imposed head motion.

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Retroperitoneal lipoma is exceedingly rare, and due to the difficulty in distinguishing between retroperitoneal lipoma and well-differentiated liposarcoma (WDLS), recommendation is en-bloc resection. A 58-year-old male was investigated for scrotal swelling, ultrasound and computed tomography showed a well-defined lipomatous mass occupying much of the left side of the lower abdomen. At laparotomy, a large left-sided retroperitoneal mass was found.

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Path integration is a sensorimotor computation that can be used to infer latent dynamical states by integrating self-motion cues. We studied the influence of sensory observation (visual/vestibular) and latent control dynamics (velocity/acceleration) on human path integration using a novel motion-cueing algorithm. Sensory modality and control dynamics were both varied randomly across trials, as participants controlled a joystick to steer to a memorized target location in virtual reality.

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Cannabis access laws allow for the use of cannabis in private and the trade, purchase and use of hemp-related products as a complementary medicine and for other benefits. Cannabidiol (CBD) has the treatment potential for several conditions but, with the lack of resources in South Africa to maintain the legislation, products contaminated with delta-9-tetrahydrocannabinol (Δ9-THC) are sold by some suppliers who do not comply with the legislative provisions in terms of the threshold concentrations for Δ9-THC. This dilemma complicates a medical review officer's decision regarding intentional use of Δ9-THC or otherwise, since a CBD user may have purchased the product legally and in good faith.

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