Optogenetics Nobel Highlights Advances in Studying and Controlling Neurons

Researchers whose work led to optogenetics have won the 2026 Nobel Prize in physiology or medicine, according to The Conversation. The technique allows neuroscientists to use light to manipulate neuronal activity millisecond by millisecond, helping them investigate how the brain functions.

The Conversation placed the breakthrough within a sequence of technological developments that enabled scientists to visualise the brain, measure its activity and control neurons. It described the scale of the challenge: a cubic millimetre of brain tissue contains tens of thousands of neurons and supporting cells that influence one another.

Neurons do not naturally respond to the light used in optogenetics, the outlet explained. Scientists use a virus, described in the report as harmless, to deliver instructions that make some neuronal proteins responsive to light. This enables researchers to target the activity of particular groups of neurons.

According to The Conversation, researchers are testing whether optogenetics can alleviate symptoms or improve treatment for conditions including vision loss, Alzheimer’s disease, Parkinson’s disease, epilepsy, multiple sclerosis, diabetes and cancer. The report describes ongoing investigations, rather than establishing that the technique is an effective treatment for all these conditions.

The article traced earlier advances to the late 1800s, when Spanish neuroscientist and artist Santiago Ramon y Cajal painted neurons observed through a microscope. He examined brain tissue made visible with a silver-staining technique developed by Italian neuroscientist Camillo Golgi. Their work received the 1906 Nobel Prize in physiology or medicine.

The Conversation reported that tracing methods developed in the 1970s subsequently helped scientists map pathways between neurons. More recent techniques include electron microscopy, which uses electrons to produce highly detailed images, and expansion microscopy, which physically enlarges tissue samples to reveal cells and their connections.

Combined with artificial intelligence algorithms, these methods allow researchers to examine the complexity within a cubic millimetre of brain tissue, according to the outlet. Mapping neuronal connections forms the field of connectomics.

The report also highlighted functional magnetic resonance imaging, which measures blood flow to investigate activity across the brain without invasive procedures. It noted that the development of MRI techniques supporting functional MRI received the 2003 Nobel Prize in physiology or medicine.

Measuring electrical signals provided another route to understanding neurons. The Conversation reported that Alan Hodgkin and Andrew Huxley received the 1963 Nobel Prize in physiology or medicine for work measuring the electrical impulses neurons use to communicate.

Modern probes can record hundreds of neurons across different brain areas simultaneously, the outlet said. It cited studies published in 2025 showing that 95% of an animal’s brain was actively involved while it made a decision, rather than only areas traditionally associated with decision-making.

The Conversation also described deep brain stimulation, developed by French neurosurgeon Alim-Louis Benabid in the late 1980s to help relieve Parkinson’s symptoms. It noted that implanted electrodes influence nearby cells, making the method less precise than newer approaches.

Another technique, designer receptors exclusively activated by designer drugs, or DREADDs, uses viral instructions to alter neuronal receptors so they respond to specific drugs. Unlike optogenetics, it controls neuronal activity chemically rather than through light. According to The Conversation, clinical trials are testing its potential for Parkinson’s disease, epilepsy and neuropathic pain.

Sources

• The Conversation: Optogenetics wins the Nobel – one neuroscience breakthrough in a line of technological innovations helping scientists map and control the brain