Summary: A revolutionary neurotechnology breakthrough has solved a historic engineering bottleneck by enabling scientists to simultaneously record and manipulate individual neuron activity deep within the living brain. The device, dubbed Neuropixels Opto, fuses large-scale electrophysiology with precise optogenetic light control on a single silicon shank narrower than a human hair.
Tested in mammalian mouse models, this next-generation probe has already shattered long-held assumptions about the architecture of the cerebral cortex, providing a high-resolution toolkit to decode the circuit disruptions underlying Alzheimerโs disease, schizophrenia, and Parkinsonโs disease.
Key Facts
- The Unified Neural Interface: Traditionally, neuroscientists have been forced to treat the brain look-or-control style: using separate electrophysiological probes to listen to raw electrical signals, and optogenetics to manipulate them with light. Combining these tools deep within subcortical structures without corrupting sensitive electrical recordings has been an impossible engineering barrier, until now.
- The Micro-Hair Silicon Architecture: Neuropixels Opto packs approximately 1,000 tightly spaced micro-recording sites alongside an array of microscopic light emitters onto a single silicon probe thinner than a human hair. This allows researchers to capture high-resolution electrical waveforms while firing precisely targeted light stimulation at multiple deep-brain sites simultaneously.
- A ยฃ15 Million Global Alliance: This breakthrough forms part of a massive ยฃ15 million scaled technology initiative funded by the Wellcome Trust, the Allen Institute, and international partners. The project is spearheaded by visual neuroscience pioneer Professor Matteo Carandini and co-lead author Dr. Karolina Socha at the UCL Institute of Ophthalmology.
- Shattering the Cortical Interconnection Myth: Utilizing Neuropixels Opto to audit the cerebral cortex, Dr. Socha uncovered a striking biological surprise. Neuroscientists long assumed that cortical neurons were so densely interconnected that stimulating a small cluster would inevitably flash a cascading wave across neighboring networks. Neuropixels Opto proved that cortical neurons can operate with remarkable localization and extreme independent autonomy.
- Isolating Absolute Causal Relationships: By giving investigators the power to selectively activate or silence specific types of cells while tracking the real-time response of surrounding circuits in the exact same experiment, Neuropixels Opto moves neuroscience past mere correlation. It provides an active canvas to map exactly how individual cells drive perception, learning, and decision-making.
- A Diagnostic Blueprint for Brain Disorders: Complex neurological and psychiatric conditionsโincluding Alzheimer’s disease, schizophrenia, and Parkinson’s disease, are driven by profound disruptions in circuit communication. By providing an accessible, high-resolution view of neural networks in both healthy and diseased states, this open tool helps global science engineer hyper-targeted medical interventions.
Source: UCL
A new breakthrough technology, co-developed by UCL scientists, that simultaneously records and manipulates neuron activity deep within the brain could transform our understanding of neural circuits and neurological conditions, such as Alzheimerโs disease and schizophrenia.
The device, known as Neuropixels Opto and researched in mice, integrates two powerful but traditionally separate techniques โ electrophysiology (the study of the electrical activity of living cells) and optogenetics (combining genetics and optics to control cells). They form a single probe, enabling unprecedented insight into how individual neurons in the brain function and interact.
Published in Nature Methods, the system allows researchers to monitor the electrical activity of hundreds of neurons while also selectively activating or silencing specific cells using light.
Developed by an international team, led by scientists at UCL and at the Allen Institute (Seattle, US), the research forms part of a ยฃ15 million project, funded by the Wellcome Trust, Allen Institute, and other partners, investigating Neuropixels probe technology.
Scientists believe Neuropixels Opto could transform our understanding of the brain by revealing how individual neurons interact within complex circuits to drive behaviour, perception and disease.
Co-author Professor Matteo Carandini (UCL Institute of Ophthalmology) said: โThe brain processes information through complex patterns of electrical activity, with billions of neurons communicating via rapid electrical signals.
โUnderstanding how these signals give rise to behaviour, thought and disease requires tools that can both observe and influence neuronal activity.
โUntil now, scientists have typically relied on separate approaches: electrophysiological probes to record neural activity, and optogenetics to control it. Combining the two has proved challenging, particularly in deeper brain regions, where delivering light without disrupting sensitive recordings is technically difficult.
โNeuropixels Opto overcomes these limitations by integrating both capabilities into a single device, enabling simultaneous measurement and manipulation of neural circuits.โ
A probe smaller than a human hair
At the centre of the technology is a silicon probe narrower than a human hair, equipped with hundreds of recording sites as well as microscopic light emitters.
These features allow the probe to capture detailed electrical signals from neurons distributed along its length while delivering precisely targeted light stimulation at multiple sites in the brain.
Professor Carandini, a Professor of Visual Neuroscience at UCL, added: โThis 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.
โThe ability to both record and control neuronal activity in the same experiment represents a significant advance for neuroscience.โ
Co-lead author, Dr Karolina Socha, a Research Fellow at UCL Institute of Ophthalmology, has started to use these probes to investigate the function of the cerebral cortex โ responsible for many of the brainโs most advanced capabilities. She says her studies in mice provide some surprising observations.
โBy 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,โ she said.
โWe 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.โ
This approach is expected to help address longstanding questions in neuroscience, including how information is processed across brain regions and how specific neural circuits contribute to perception, learning and decision-making.
Implications for studying brain disorders
The technology may also have important implications for understanding neurological and psychiatric conditions.
Many disorders, including schizophrenia, Alzheimerโs disease and Parkinsonโs disease, are associated with disruptions in how neurons communicate. By providing a clearer picture of how neural circuits function in both healthy and diseased states, Neuropixels Opto could support the development of more targeted treatments.
The development of Neuropixels Opto involved a wide-ranging collaboration between institutions in the US, UK and Europe, alongside engineering partners.
The work forms part of a broader effort to develop advanced tools for studying the brain at scale, with the aim of making high-resolution, large-scale neural recording more accessible to researchers worldwide.
A step forward for neuroscience tools
Neuropixelsย are next-generation silicon probes that act like tiny electrodes, allowing scientists to record the electrical activity of hundreds of neurons simultaneously across different brain regions.
By packing around 1,000 closely spaced recording sites onto an ultra-thin probe, they make it possible to capture high-resolution signals from individual brain cells while monitoring large neural networks at the same time.
Key Questions Answered:
A: Because the equipment required to control brain cells would systematically blind the equipment trying to listen to them. Scientists used metal electrodes to record electrical pulses, and optogenetics (light-activated proteins) to control neurons. However, trying to blast light deep into brain tissue without generating massive electrical noise and disrupting the sensitive recording sites proved to be a massive engineering dead end.
A: By leveraging state-of-the-art micro-silicon engineering to build an interface narrower than a human hair. The probe is built with roughly 1,000 closely spaced microscopic recording nodes packed along its ultra-thin shaft. Interwoven directly between these recorders are microscopic light emitters, allowing a single tiny wire to simultaneously act as a high-definition microphone and a targeted spotlight.
A: It proved that brain cells are far more independent than we ever imagined. For decades, the scientific consensus was that the neurons in our cerebral cortex were so tightly interconnected that activating a few would automatically trigger a massive, synchronized domino effect across the surrounding network. Neuropixels Opto proved that these neurons can actually toggle their activity with pinpoint localization, operating completely solo right next to resting cells.
Editorial Notes:
- This article was edited by a Neuroscience News editor.
- Journal paper reviewed in full.
- Additional context added by our staff.
About this neurotech research news
Author:ย Henry Killworth
Source:ย UCL
Contact:ย Henry Killworth โ UCL
Image:ย The image is credited to Neuroscience News
Original Research:ย Closed access.
โNeuropixels Opto: combining high-resolution electrophysiology and optogeneticsโ by Anna A. Lakunina, Karolina Z. Socha, Alexander E. Ladd, Anna J. Bowen, Susu Chen, Jennifer Colonell, Anjal Doshi, Bill Karsh, Michael Krumin, Pavel Kulik, Anna J. Li, Pieter Neutens, John OโCallaghan, Meghan Olsen, Jan Putzeys, Charu Bai Reddy, Harrie A. C. Tilmans, Sara Vargas, Marleen Welkenhuysen, Zhiwen Ye, Michael Hรคusser, Christof Koch, Jonathan T. Ting, Barundeb Dutta, Timothy D. Harris, Nicholas A. Steinmetz, Karel Svoboda, Joshua H. Siegle & Matteo Carandini.ย Nature Methods
DOI:10.1038/s41592-026-03076-z
Abstract
Neuropixels Opto: combining high-resolution electrophysiology and optogenetics
High-resolution extracellular electrophysiology is the gold standard for recording spikes from distributed neural populations and is especially powerful when combined with optogenetics for manipulation of specific cell types with high temporal resolution.
We integrated these approaches into prototype Neuropixels Opto probes, which combine electronic and photonic circuits. These devices pack 960 electrical recording sites and two sets of 14 light emitters onto a 70-ฮผm-wide, 1-cm-long shank, allowing spatially addressable optogenetic stimulation with blue and red light.
In mouse cortex, Neuropixels Opto probes delivered high-quality recordings together with spatially addressable optogenetics, differentially activating or silencing neurons at distinct cortical depths.
In the mouse striatum and other deep structures, Neuropixels Opto probes delivered efficient optotagging, facilitating the identification of two cell types in parallel. Neuropixels Opto probes represent a promising tool for recording, identifying and manipulating neuronal populations.
