A switch for nerve cells, borrowed from pond algae

In plain terms

Early 1990s

Hegemann asks how an alga finds the light.

2002–03

Hegemann and Nagel describe the channelrhodopsins.

2005

Deisseroth’s laboratory fires rat nerve cells with light.

2021

First report of partial sight restored to a blind patient.

2026

The prize. The first optogenetic treatment is under review at the FDA, with a decision expected in the first half of 2027.

Say it accurately

“Scientists can now control the brain with light.”

Only cells that have first been given the algal gene respond, and the light has to reach them, in the brain usually through an implanted fibre. Light on an ordinary head does nothing.

“They have found the neurons for fear, or memory, or love.”

The experiments show that switching on a certain group of cells is enough to produce a behaviour in a mouse. That is a finding about a circuit in an animal. A claim about human experience is a further step, and the experiment does not take it.

“This proves we are nothing but our neurons.” Or the reverse: “This cannot touch the soul.”

The finding is that behaviour depends on brain activity in very precise ways. Whether a person is more than that activity is a question of philosophy and theology. The experiments do not settle it in either direction. Wesley granted the dependence and denied the reduction; see the shelf below.

“A cure for blindness,” or for depression.

The clearest human result is partial sight in one eye, with goggles and months of training. No optogenetic treatment had regulatory approval when the prize was announced. For psychiatric illness it remains a research tool used in animals.

“Three people invented this.”

The rules allow at most three laureates. The committee’s own background paper names others, among them Gero Miesenböck, who first made nerve cells respond to light by genetic means in 2002, and Zhuo-Hua Pan, who had the algal protein working in cells of the retina in 2004 but could not get the result published until 2006. Ed Boyden was first author of the 2005 paper and was a student in Deisseroth’s laboratory.

For preaching

• Sight that comes in stages Instance

  Mark 8:22–26 · John 9

  The 2021 patient did not open his eyes and see. He first reported a change about seven months in, and what returned was partial. Mark’s blind man at Bethsaida also sees in stages. Here is a real healing that is slow, incomplete, the work of many hands, and still good.

• Those who laboured and were not named Instance

  John 4:37–38 · 1 Corinthians 3:6–9 · 1 Corinthians 12

  Each laureate, when the call came, said how glad he was to share the prize with the other two, and called them friends. Others did work the prize depends on and were left out by a rule of three. “Others have labored, and you have entered into their labor” (John 4:38, WEB).

• The lowly thing chosen Likeness

  1 Corinthians 1:27–28 · Job 12:7–8 · Proverbs 25:2

  One of the most powerful tools in brain science came out of pond scum, studied by a man who only wanted to know how it found the light. “It is the glory of God to conceal a thing, but the glory of kings is to search out a matter” (Proverbs 25:2, WEB).

• Light that acts Likeness

  Genesis 1:3 · Psalm 36:9 · 2 Corinthians 4:6 · Ephesians 5:13–14

  Deisseroth observed that science usually treats light as a way of looking at things, and that here light makes something happen. In Scripture, too, light does more than reveal. Borrow the image and stop there. The laboratory has not found the light John’s prologue speaks of.

On the Wesleyan shelf

• Thoughts upon Necessity (1774)

  Wesley met the brain science of his own day in David Hartley, who traced every thought to vibrations in the fibres of the brain. His answer has two halves, and they should be kept apart. He concedes the dependence: “who can deny, that not only the memory, but all the operations of the soul, are now dependent on the bodily organs, the brain in particular?” (§IV.2). He refuses the conclusion that every human action is therefore necessary. The preface puts the refusal in one line: “I cannot believe the noblest creature in the visible world to be only a fine piece of clock-work.” A sermon on this prize can concede as much as he did.

• Wandering Thoughts (sermon on 2 Corinthians 10:5)

  “Let but the blood move irregularly in the brain, and all regular thinking is at an end” (§II.3). Wesley’s pastoral conclusion is that thoughts arising from a disordered body are not sin. When preaching near mental illness, the science supports a distinction he had already drawn. See also “Heaviness through Manifold Temptations” (1 Peter 1:6) and “Thoughts on Nervous Disorders” (1786).

• The Desideratum: or, Electricity Made Plain and Useful (1760)

  In November 1756 Wesley procured an electrical apparatus and began offering treatment to the sick, soon for an hour every day (Journal, 9 November 1756). Stimulating the nerves with the newest physical technology, for the sake of the sick, has a Methodist history. So does the caution that goes with it: his confidence in electricity ran ahead of the evidence.