LONDON — Neuropixels Opto, a new brain probe that simultaneously records and manipulates neuron activity deep within the brain, was developed by an international team led by scientists at University College London and the Allen Institute in Seattle, U.S. The device integrates electrophysiology and optogenetics into a single probe, enabling researchers to monitor the electrical activity of hundreds of neurons while selectively activating or silencing specific cells using light.
The probe is narrower than a human hair and equipped with hundreds of recording sites and microscopic light emitters. Neuropixels probes, the foundation of this technology, are next-generation silicon probes that function as tiny electrodes with around 1,000 closely spaced recording sites, allowing simultaneous observation of neural activity across different brain regions.
The research was conducted in mice and published in Nature Methods in 2026 under the title “Neuropixels Opto: combining high-resolution electrophysiology and optogenetics” by Lakunina, A.A., et al. The work emerged from a £15 million project funded by the Wellcome Trust, the Allen Institute, and other partners, and involved collaboration between institutions in the U.S., the U.K., and Europe, alongside engineering partners.
Matteo Carandini, Professor of Visual Neuroscience at UCL Institute of Ophthalmology and co-author of the study, said the technology enables new types of experiments. “The ability to both record and control neuronal activity in the same experiment represents an advance for neuroscience.” He said, “This makes it possible, for the first time, to directly test how specific neurons influence the activity of surrounding circuits – revealing causal relationships between neuronal activity and brain function.”
Dr. Karolina Socha, Research Fellow at UCL Institute of Ophthalmology and co-lead author of the study, described early findings made possible by the probe. “By selectively activating or silencing specific types of neurons while monitoring the response of nearby cells, we can begin to map how different components of the brain work together to produce behaviour.” She said, “We were surprised to discover that the activity of neurons in the cortex can be remarkably localised. Up to now, we thought that neurons are so interconnected that there would be no way to activate some of them without activating many others. The new Neuropixels Opto probes revealed that these neurons can operate not only in concert but also rather independently.”
Researchers suggest the technology may help address longstanding questions in neuroscience, including how information is processed across brain regions and how neural circuits contribute to perception, learning, and decision-making. It may also have implications for understanding neurological and psychiatric conditions such as schizophrenia, Alzheimer's disease, and Parkinson's disease.