Physicists of Novosibirsk State Technical University (NETI), together with neurophysiologists from the Institute of Physiology named I.I. Pavlov, Russian Academy of Sciences, has developed an innovative method for minimally invasive, highly selective infrared neural stimulation using a fiber-optic interface between the brain and a laser source.
Currently, electrical, magnetic, infrared, and ultrasound methods of neural stimulation of the brain are used in physiology, basic medicine, and clinical practice. Choosing a specific method for implementing stimulation is always a compromise between simplicity, safety and comfort, which are characteristic of non—invasive transcranial methods, and high efficiency, which requires selective stimulation of individual brain regions with high temporal and spatial resolution, which requires complex invasive forms of stimulation with neurosurgical intervention. Scientists from Novosibirsk University and the Institute of Physiology of the Russian Academy of Sciences from St. Petersburg have proposed a new practical method for selective neural stimulation of the brain, which involves the use of laser radiation and a fiber-optic interface.
The method differs favorably from transcranial stimulation methods with a significantly higher (submillimeter) spatial resolution, and from previously known laser stimulation methods — by the absence of the need for preliminary genetic manipulations and its minimally invasiveness, due to which it is not necessary to disrupt the integrity of the meninges. In addition, the developed method almost does not limit the basic vital functions of patients.
According to Boris Nyushkov, one of the developers of the method, head of the Scientific Laboratory of General and Applied Photonics at NSTU-NETI, Head of the Department of Laser Systems at the Faculty of Physics and Technology, Candidate of Sciences in Physics and Mathematics, Associate Professor, this method was made possible by creating a unique fiber-optic interface between a laser source of stimulating patterns and the surface of the cerebral cortex. "The minimally invasive nature of the point implantation of such an interface makes it possible to preserve the integrity of the meninges, and its flexibility does not limit the basic vital functions and mobility of the patient's head," Boris Nyushkov noted.
An innovative approach in neurophysiology made it possible to conduct a long-term (multi-day) experiment on dynamic infrared neural stimulation of a selected area of the cerebral cortex and synchronous recording of the complex electrophysiological response of various parts of it to local stimulation in a rhesus macaque without anesthesia, which remained in states of natural sleep and wakefulness throughout the experiment. According to Alexey Kharauzov, head of the scientific group of physiologists who conducted the neurophysiological study, senior researcher at the Institute of Physiology of the Russian Academy of Sciences, Candidate of Biological Sciences, scientists were convinced of the feasibility and safety of a new approach to targeted laser infrared neural stimulation and registration of electrophysiological responses.
"The method opens up new opportunities for the scientific and medical community both for instrumental studies of the complex interaction of functional brain regions and the deepening of fundamental knowledge about the work of the brain and the central nervous system as a whole, and for the development of new clinical therapies for various disorders in the central nervous system," emphasized Alexey Kharauzov.
Igor Korel, Dean of the Faculty of Physics and Technology of NSTU NETI, Candidate of Physico-Mathematical Sciences, Associate Professor, who is a participant of the research, noted the importance of joint work. "This is a vivid example of the productivity of an interdisciplinary research format, when a unique result of such high practical significance was obtained literally at the junction of two different fields of scientific knowledge — laser photonics and neurophysiology," said Igor Korel.
The joint research work was presented at the BRICS Scientific Symposium on Biophotonics (BRICS Workshop on Biophotonics IV), and its results were published in the international scientific journal Brain Topography.
Earlier, scientists at NSTU-NETI developed new methods for generating and controlling laser pulses, which make it possible to increase the reliability and energy efficiency of laser sources, as well as expand their functionality to solve various applied problems. The results of this work were presented at the IEEE International Scientific and Technical Conference "Actual Problems of Electronic Instrumentation" APEP-2025.