On October 5, the Nobel Committee awarded the 2026 Prize in Physiology or Medicine to Karl Deisseroth, Peter Hegemann and Georg Nagel for work on light-gated ion channels and optogenetics, the technique that switches individual nerve cells on or off with light.

A Nobel is a good moment to ask what a research tool has become. We counted the papers and the trials.

How big did the field get?

Source: NCBI PubMed via E-utilities, queried October 12, 2026. A keyword count, not a count of unique studies or of experiments that used the method. 2026 is a partial year (1,383 records so far) and is left out.

View data

year	papers
2006	2
2007	5
2008	6
2009	25
2010	80
2011	173
2012	287
2013	498
2014	610
2015	814
2016	904
2017	998
2018	1163
2019	1163
2020	1361
2021	1504
2022	1394
2023	1557
2024	1572
2025	1745

That is a 22-fold rise from 80 records in 2010 and a 2.1-fold rise from 814 in 2015. The curve is flattening: 2018 and 2019 both returned 1,163, and growth since 2020 has been about 5% a year in our count. A technique at this stage is infrastructure. Labs use it the way they use a microscope.

How many of those papers are medicine?

Very few, by the trial register. ClinicalTrials.gov returns 15 studies for the word optogenetic. Nine of them are interventional trials of an optogenetic gene therapy, and all nine target the retina: retinitis pigmentosa, Stargardt disease or choroideremia. The rest are long-term follow-up or observational studies, and one is an unrelated acoustic biofeedback study.

Source: ClinicalTrials.gov API v2, queried October 12, 2026. Our search used one term. Trials that describe the same approach with other words, for example light-sensitive proteins, may be missing. Two of the 2026 entries have not started recruiting or only just began.

View data

start	trials
2015	1
2018	1
2019	1
2021	1
2022	1
2024	2
2026	2

The eye is a sensible first target. It is accessible to an injection, the light is already there, and a blind retina has no photoreceptors left to lose. The trial list has no brain disease in it. Controlling neurons with light inside the skull needs a delivery route and a light source, and the register shows no sponsor has yet filed a trial that does so.

Why does the gap matter?

A tool can win a Nobel because it changed what scientists can ask. A medicine needs something different: a delivery method, a safety record and a regulator. The distance between 1,745 papers and nine trials is a measure of how much of the work is still on the research side of that line.

What this does and does not show

PubMed counts depend on the search term and on how authors describe their work, and they count records, not discoveries. The trial count depends on one search term and on registration, so it is a floor. We did not review trial results, so we say nothing about whether any of the nine works. The laureates and the prize reasoning come from news reports of the announcement; the Nobel Committee site did not load for us.

Sources

1. NCBI, PubMed, queried through the E-utilities API on October 12, 2026: yearly counts for the term optogenetics.
2. ClinicalTrials.gov, API v2 search for optogenetic, queried October 12, 2026: 15 studies, nine interventional gene-therapy trials by start date.
3. The Nobel Prize, Physiology or Medicine 2026, and NPR via WUNC, Nobel medicine prize goes to 3 scientists for research into brain activity, October 5, 2026: laureates, affiliations, 12 million Swedish crowns.
4. Our earlier analyses: CRISPR's first approval did not set off a rush of trials and Trials do not grow together.