Ram Prasadh Narayanan

arXiv2026

Frequency demodulation with magnetoelectric coreshells: A novel approach to enhanced bio-stimulation

Magnetoelectric (ME) coreshell devices have interesting applications in biomedical technologies including biosensing and communication, due to their strong inter-coupling between the magnetostrictive core and the piezoelectric shell. This property could be utilized for specific applications in localized bio-stimulation of cells. This paper provides a conceptual proof of using the non-linear property of ME coreshell devices for frequency demodulation and stimulation. We use the Multiphysics simulation approach, wherein the ME coreshell was biased with a DC magnetic field and perturbed through dual coil alternating magnetic fields. The combined effect of the ME non-linear magnetostriction and the dual coil perturbation resulted in the demodulation of the interference frequency component, that induced equivalent electrical hotspots on the piezoelectric shell. We provide a cross model verification, where the generated electrical current density on the piezo shell was provided as an input to a Hodgkin-Huxley (HH) neural cell model to actively induce membrane potentials on the cell. Future applications as a standalone, battery- and electronics-free, controllable, multi-functional and localized coreshells for targeted drug delivery, backscatter communication and bio-stimulation, is envisioned.

eess.SP↗

arXiv2026

Design and Validation of a Modular Smart Headband with Embroidered Electrodes for Comfortable EEG Monitoring

The wearable EEG device sector is advancing rapidly, enabling fast and reliable detection of brain activity for investigating brain function and pathology. However, many current EEG systems remain challenging for users with neurological conditions due to bulky wiring, lengthy skin preparation, gel-induced discomfort, risk of irritation, and high cost, all of which limit long-term monitoring. This study presents a proof-of-concept smart modular headband incorporating adjustable, replaceable embroidered electrodes for EEG acquisition. Compared with conventional devices, the smart headband reduces wiring complexity, removes the need for skin preparation, and minimizes irritation associated with gel-based electrodes. Its modular structure allows adjustable fitting without requiring multiple size options, enhancing comfort and adaptability for everyday EEG monitoring. The smart headband prototype was tested on 10 healthy university students using three behavioral tasks: (1) eyes open/closed, (2) auditory oddball, and (3) visual oddball paradigms. The smart headband successfully captured alpha peaks during the eyes-open/closed task (p = 0.01) and reliably recorded the event-related potentials associated with the oddball effects - the auditory P300 (p = 0.014) and the visual N170 (p = 0.013) - demonstrating an equivalent performance to a commercial sponge-based EEG cap. A user survey indicated improved comfort and usability, with participants reporting that the soft, structurally designed headband enhanced wearability relative to a conventional cap. Overall, this prototype provides a comfortable, modular, and cost-effective solution to reliable EEG monitoring in real-world applications.

cs.ET↗