Indian Scientists Construct a Powerful Artificial Synaptic Network to Imitate the Human Brain

Scientists at the Jawaharlal Nehru Centre for Advanced Scientific Research in Bengaluru, an autonomous institute of the Indian government's Department of Science and Technology, developed a new approach for fabricating an artificial synaptic network (ASN) that resembles the biological neural network using a simple self-forming technique (the device structure is formed by itself while heating).

The JNCASR team investigated a material system that mimicked neuronal bodies and axonal network connection, much like the biological system, in order to produce a synaptic device for neuromorphic applications with a simple fabrication procedure. They discovered that a self-forming mechanism was simple, scalable, and cost-effective for creating such a structure.

In their research, the JNCASR team dewetted Silver (Ag) metal to create branched islands and nanoparticles with nanogap separations that resembled bio neurons and neurotransmitters. Dewetting is a process that involves rupturing a continuous film into disconnected/isolated islands or spherical particles. Numerous higher-order cognitive activities can be simulated using such an architecture.

The fabricated artificial synaptic network (ASN) consisted of a Silver (Ag) agglomerates network separated by nanogaps filled with isolated nanoparticles. They discovered that dewetting the Ag film at a higher temperature culminated in the creation of island structures split by nanogaps, which resembled a bio-neural network.

This hierarchical structure simulated numerous learning activities such as short-term memory (STM), long-term memory (LTM), potentiation, depression, associative learning, interest-based learning, supervision, and so on, leveraging programmed electrical signals as a real-world stimulus. Excessive learning-induced synaptic exhaustion and subsequent self-recovery were also simulated.

According to the report, remarkably, all these behaviors were emulated in a single material system without the aid of external CMOS circuits. A prototyping kit has been developed to emulate Pavlov's dog behavior which demonstrates the potential of this device towards neuromorphic artificial intelligence. By organizing a nanomaterial resembling the biological neural substance, the JNCASR team has moved a step further in accomplishing advanced neuromorphic artificial intelligence.