Biology subjects

Boys, A. J.

Publications and source records attributed to Boys, A. J..

3 recordsLinked to original sources

bioRxiv2024

Development of novel signal and spike velocity analysis tools in peripheral nerve cuffs

ObjectivePeripheral nerve neurotechnologies hold significant promise as avenues for new closed-loop clinical treatments. However, analysis tools for nerve recordings - a key component of closed-loop nerve technologies - remain underdeveloped compared to brain-focused methods. This study introduces and explores the performance of two novel nerve signal analysis techniques which rely on a defining feature of peripheral nerve signals: the reliable conduction velocity of signals transmitted by axons in nerves. ApproachWe test the capabilities of the introduced cross-correlation and spike delay velocity analysis techniques both in silico on synthetic nerve signals and on in vivo nerve signals acquired from freely-moving rats. Main resultsOur findings show that both techniques can be successfully employed to extract transmission direction and velocity information from nerve cuff recordings. Notably, cross-correlation analysis can be employed to detect neural signals of very low signal-to-noise ratio, otherwise undetectable by typical spike detection approaches. SignificanceOur findings provide new techniques to both enhance detection and extract new information in the form of velocity data from nerve recordings. As axon signal conduction direction and velocity is tightly linked to neural function, these techniques can support new research into peripheral nervous system function and new therapeutic approaches driven by neural interfaces.

neuroscience↗

bioRxiv2024

Implantable Bioelectronics for Real-time in vivo Recordings of Enteric Neural Activity

The gastrointestinal tract is regulated by a complex network of electrically-active cell types that communicate to drive gut function. One of these systems, the enteric nervous system, represents a primary point of contact for a host of factors that influence bodily health and behavior. This division of the autonomic nervous system is unique in both its extensivity, with neurons distributed throughout the gastrointestinal tract from the esophagus to the rectum, and its capability for local information processing. However, the constant intrinsic and extrinsic motion of the gut as well as the sparse distribution of the neurons that constitute the enteric nervous system has made, access and analysis for study of this important component of the gastrointestinal tract exceedingly challenging. Here, we present the construction and validation of a bioelectronic implant for accessing neural information from the distal colon. The implant, constructed for compatibility with a novel surgical approach applicable across multiple species, is designed to be positioned within the colonic wall in close proximity to the enteric nervous plexi. We captured complex multi-frequency electrophysiological responses to neural chemical stimulants and showed that we can record distension activity mimicking gut motility. We also show the feasibility of utilizing this device for recording from putative single neurons in freely-moving rats and examining colonic activity in the context of food intake and stress. This work marks a significant advancement in understanding the complex pathways of the gut-brain axis. Our bioelectronic monitoring system demonstrates the power of real-time electrophysiological monitoring for the distal areas of the autonomic nervous system. Furthermore, direct access to the communication pathways of the enteric nervous system paves the way for novel neuromodulation strategies targeting the gut-brain axis.

neuroscience↗

bioRxiv2022

3D Bioelectronics with a Remodellable Matrix for Long-term Tissue Integration and Recording

Bioelectronics hold the key for understanding and treating disease. However, achieving stable, long-term interfaces between electronics and the body remains a challenge. Implantation of a bioelectronic device typically initiates a foreign body response, which can limit long-term recording and stimulation efficacy. Techniques from regenerative medicine have shown a high propensity for promoting integration of implants with surrounding tissue, but these implants lack the capabilities for the sophisticated recording and actuation afforded by electronics. Combining these two fields can achieve the best of both worlds. Here, we show the construction of a hybrid implant system for creating long-term interfaces with tissue. We create implants by combining a microelectrode array with a bioresorbable and remodellable gel. These implants are shown to produce a minimal foreign body response when placed into musculature, allowing us to record long-term electromyographic signals with high spatial resolution. This device platform drives the possibility for a new generation of implantable electronics for long-term interfacing.

bioengineering↗