CLAASIC: a Cortex-Inspired Hardware Accelerator



This work explores the feasibility of specialized hardware implementing the Cortical Learning Algorithm (CLA) in order to fully exploit its inherent advantages. This algorithm, which is inspired in the current understanding of the mammalian neo-cortex, is the basis of the Hierarchical Temporal Memory (HTM). In contrast to other machine learning (ML) approaches, the structure is not application dependent and relies on fully unsupervised continuous learning. We hypothesize that a hardware implementation will be able not only to extend the already practical uses of these ideas to broader scenarios but also to exploit the hardware-friendly CLA characteristics. The architecture proposed will enable an unfeasible scalability for software solutions and will fully capitalize on one of the many CLA advantages: very low computational requirements and optimal storage utilization. Compared to a state-of-the-art CLA software implementation it could be possible to improve by 4 orders of magnitude in performance and up to 8 orders of magnitude in energy efficiency. Embracing the problem’s complex nature, we found that the most demanding issue, from a scalability standpoint, is the massive degree of connectivity required. We propose to use a packet-switched network to tackle this. The paper addresses the fundamental issues of such an approach, proposing solutions to achieve scalable solutions. We will analyze cost and performance when using well-known architecture techniques and tools. The results obtained suggest that even with CMOS technology, under constrained cost, it might be possible to implement a large-scale system. We found that the proposed solutions enable a saving of ~90% of the original communication costs running either synthetic or realistic workloads.