JNCASR's Frog-Inspired Humidity-Responsive Neuromorphic Sensor Advances Energy-Efficient AI in India

In a groundbreaking advancement from India's research landscape, scientists at the Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR) in Bengaluru have engineered a humidity-responsive neuromorphic sensor inspired by the natural synaptic behavior of cricket frogs. This innovative device, detailed in a recent publication in the Journal of Materials Chemistry C, promises to slash energy consumption in artificial intelligence (AI) and Internet of Things (IoT) applications by integrating sensing, memory, and processing into a single ultra-efficient platform. As India's higher education and research ecosystem pushes boundaries in bio-inspired technologies, this development underscores JNCASR's role as a deemed university driving next-generation electronics.

The sensor's ability to mimic brain-like responses to environmental humidity addresses a critical bottleneck in conventional electronics: high power usage and data transfer overheads. Traditional systems separate sensing from processing, leading to inefficiency, but this frog-inspired design emulates biological synapses, where environmental cues like moisture directly modulate neural activity. With neuromorphic computing gaining traction globally, this Indian innovation positions the country at the forefront of energy-efficient edge computing.

JNCASR, established in 1989 as an autonomous institute under the Department of Science and Technology (DST), Govt. of India, holds deemed university status granted by the University Grants Commission (UGC) in 2002. Located in Jakkur, Bengaluru, it offers Ph.D., Integrated Ph.D., and M.Sc. programs across chemistry, physics, materials science, biology, and engineering, fostering over 500 researchers in an interdisciplinary environment. Ranked among India's top research institutions—4th in Nature Index for life sciences in 2020—JNCASR exemplifies how premier research centers contribute to higher education by blending advanced training with cutting-edge discoveries.

Leading the project is Prof. Giridhar U. Kulkarni, Chair of the Chemistry and Physics of Materials Unit, alongside Subi J. George from the Supramolecular Chemistry Laboratory, Sukanya Baruah, and Tejaswini S. Rao. Their work builds on JNCASR's legacy in neuromorphic devices, including previous efforts on crack-template synapses and stretchable metal networks, highlighting the institute's focus on sustainable computing solutions relevant to India's burgeoning AI sector.

Neuromorphic computing (from 'neuro' meaning nerve and 'morphic' meaning form) replicates the human brain's architecture using artificial neurons and synapses, diverging from the von Neumann model where processing and memory are separate. This paradigm shift enables parallel processing, low latency, and minimal power draw—crucial for AI tasks like pattern recognition and IoT data handling.

In India, neuromorphic tech aligns with national priorities under the National AI Strategy and IndiaAI Mission, projected to propel the market from USD 192 million in 2023 to USD 924 million by 2030 at 18.4% CAGR. JNCASR's sensor advances this by using humidity as a stimulus, a first in the field, enabling adaptive learning without constant power input.

Step-by-step, neuromorphic sensors work like this: (1) Input stimuli (e.g., humidity) alter conductance in synaptic materials; (2) Synaptic weight changes mimic short-term plasticity (e.g., paired-pulse facilitation); (3) Long-term memory via metaplasticity; (4) Output as spike-like electrical signals for processing. Unlike silicon chips consuming milliwatts per operation, these bio-mimics operate in nanowatts, ideal for battery-powered IoT.

Cricket frogs (Fejervarya limnocharis), common in India's wetlands, exhibit synaptic activity highly tuned to humidity. Studies show their neural firing ramps up with rising moisture, peaking during monsoons for breeding, while daylight modulates response. Field observations reveal they maintain optimal hydration (near 80-90% body water) for maximum jump performance, with behavior shifting from nocturnal calls in dry conditions to diurnal activity in wet ones. Cricket frogs maintain body hydration and temperature

This natural metaplasticity—influenced by environmental cues—inspired the sensor. Just as frog synapses facilitate stronger signals after initial pulses in humid conditions (paired-pulse facilitation, PPF index up to 3.5), the device enhances response with repeated humidity exposure, demonstrating 'learning' from environment.

The sensor's heart is one-dimensional (1D) supramolecular nanofibers formed from coronene tetracarboxylate (CS, donor) and dodecyl methyl viologen (DMV, acceptor) charge-transfer complex. Fabrication: (1) Grow nanofibers in water; (2) Drop-coat on interdigitated gold electrodes (IDEs) on glass; (3) Test in humidity chamber (20-90% RH via N2 flow).

• Humidity pulses (short/long intervals) trigger conductance changes, emulating facilitation/depression.
• Light (UV/vis) enhances response, mimicking frog daylight sensitivity.
• Logic gates (AND/OR) via pulse combinations.

Performance: PPF index 3.5 (highest reported for humidity-driven), stable over cycles, room-temp operation. Energy efficiency stems from event-driven spiking—no constant polling—cutting IoT power by orders of magnitude.Full paper DOI: 10.1039/D5TC03980K

India's IoT market, valued at USD 15B in 2025, grows 25% CAGR, driven by smart cities (Smart Cities Mission) and agriculture (Digital Agriculture Mission). This sensor enables:

• Environmental Monitoring: Wearables for humidity alerts in disaster-prone areas like Kerala floods.
• Healthcare: Sweat/humidity sensors for dehydration tracking in rural clinics.
• Edge AI: Low-power anomaly detection in factories (Make in India).
• Agriculture: Soil moisture synaptic learning for precision irrigation, saving 30% water.

Case study: Similar neuromorphic tech in pilot IoT farms (e.g., ICRISAT) cut energy 70%. Scaling via JNCASR's industry ties (e.g., past nitride semiconductor collaborations) could boost India's neuromorphic chip market to USD 4B by 2031.

DST's support via SERB-Core Research Grant fueled this work, aligning with National Quantum Mission and India Semiconductor Mission. JNCASR's PhD programs train neuromorphic experts, with alumni in Intel, IBM. Collaborations like C-DAC's neuromorphic projects amplify impact.

Challenges: Scaling fabrication, integration with silicon. Solutions: Supramolecular self-assembly offers low-cost, scalable production. Future: Hybrid sensors for multi-stimuli (temp, light, humidity).

Globally, neuromorphic market hits USD 1.3B by 2030 (89% CAGR). Leaders: Intel Loihi, IBM TrueNorth. India's edge: Bio-mimicry expertise (e.g., IISc locust-inspired chips). This sensor's humidity focus fills gap in tropical climates, exporting to SE Asia.

Stakeholders: Startups like Neurolabs; academia (IITs); industry (TCS AI labs). Implications: Reduces India's data center energy (3% national consumption), aids net-zero goals.

Challenges: Stability in extreme humidity, biocompatibility. Ethical: Data privacy in IoT. JNCASR addresses via adaptive designs.

Outlook: Prototypes for wearables by 2027; patents filed. Boosts India's R&D GDP (0.7% now, target 2%). Students: Pursue JNCASR PhDs for neuromorphic careers—explore research jobs.

Photo by Sonika Agarwal on Unsplash

JNCASR exemplifies how deemed universities drive innovation, training 100+ PhDs yearly. Impacts: Attracts global talent, startups (e.g., from Incubation Centre). For faculty/students: Interdisciplinary projects like this enhance NIRF rankings, funding.

Actionable: Collaborate via DST calls; upskill in supramolecular chemistry for AI hardware.