A Multi-Site Accelerator-Rich Processing Fabric for Scalable Brain-Computer Interfacing

Karthik Sriram; Raghavendra Pradyumna Pothukuchi; Michał Gerasimiuk; Oliver Ye; Muhammed Ugur; Rajit Manohar; Anurag Khandelwal; Abhishek Bhattacharjee

arXiv · 2301.03103

A Multi-Site Accelerator-Rich Processing Fabric for Scalable Brain-Computer Interfacing

Karthik Sriram·Raghavendra Pradyumna Pothukuchi·Michał Gerasimiuk·Oliver Ye·Muhammed Ugur·Rajit Manohar·Anurag Khandelwal·Abhishek Bhattacharjee

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Abstract

Hull is an accelerator-rich distributed implantable Brain-Computer Interface (BCI) that reads biological neurons at data rates that are 2-3 orders of magnitude higher than the prior state of art, while supporting many neuroscientific applications. Prior approaches have restricted brain interfacing to tens of megabits per second in order to meet two constraints necessary for effective operation and safe long-term implantation -- power dissipation under tens of milliwatts and response latencies in the tens of milliseconds. Hull also adheres to these constraints, but is able to interface with the brain at much higher data rates, thereby enabling, for the first time, BCI-driven research on and clinical treatment of brain-wide behaviors and diseases that require reading and stimulating many brain locations. Central to Hull's power efficiency is its realization as a distributed system of BCI nodes with accelerator-rich compute. Hull balances modular system layering with aggressive cross-layer hardware-software co-design to integrate compute, networking, and storage. The result is a lesson in designing networked distributed systems with hardware accelerators from the ground up.

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Karthik Sriram, Raghavendra Pradyumna Pothukuchi, Michał Gerasimiuk, Oliver Ye, Muhammed Ugur, Rajit Manohar, Anurag Khandelwal, Abhishek Bhattacharjee. 2023-01-08. A Multi-Site Accelerator-Rich Processing Fabric for Scalable Brain-Computer Interfacing. https://arxiv.org/abs/2301.03103

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