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Garcia Ramirez, J.

Publications and source records attributed to Garcia Ramirez, J..

2 recordsLinked to original sources

An intracortical brain-computer interface for navigation in virtual reality in macaque monkeys

We present an innovative intracortical Brain-Computer Interface (BCI) to bridge the gap between laboratory settings and real-world applications. This BCI approach introduces three key advancements. First, we utilized neural signals from three macaque brain regions - primary motor, dorsal and ventral premotor cortex - enabling precise and flexible decoding of real-time three-dimensional (3D) sphere/avatar velocities. Second, we developed a realistic, immersive 3D virtual reality setup with dynamic camera tracking, allowing continuous navigation and obstacle avoidance that closely mimic real-world scenarios. Finally, our BCI approach is very well suited for use by paralyzed patients, featuring a brief passive fixation without overt movements and closed-loop operation without retraining of the decoder during online decoding, relying on the users neural plasticity and the decoders robust generalization across tasks. Our BCI adapted to different environments, targets, and obstacles, illustrating its potential to substantially enhance the quality of life for paralyzed patients by enabling natural, reliable and flexible control in complex settings.

neuroscience↗

Fine-grained neural coding of bodies and body parts in human visual cortex

The visual image of a human body provides a valuable source of socially relevant information. However, our understanding of the neuronal mechanisms underlying body perception in humans remains limited given the spatiotemporal constraints of functional imaging. Here we recorded multi-unit spiking activity in two neurosurgical patients in or near the extrastriate body area (EBA), a critical region for body perception. Our recordings revealed a strong preference for human bodies over a large range of control stimuli. Notably, this preference was driven by a distinct selectivity for body parts. Moreover, the observed body selectivity generalized to non-photographic depictions of bodies such as silhouettes and stick figures. Overall, our study provides an unprecedented access into the representation of bodies in the human visual cortex to bridge the gap between human neuroimaging and macaque electrophysiology studies, and form a solid basis for computational models of human body processing.

neuroscience↗