Mind control is real?

Mind control exists (no drugs required) in 2025?! THIS IS NOT A DRILL!

Figure made in Canva by @neuro_melody

Mind control is real. It sounds like something from a sci-fi movie, a magic show, or a cult legend, but it’s not. Since the early 2000s, scientists have been using light to control brain activity in living animals, effectively controlling how those animals think, behave, and perceive the world.

This revolutionary neuroscience technology is called optogenetics.

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The Brain, Hacked by Light

Your brain is an intricate web of cells called neurons, which constantly send signals to each other. Neurons rely on electricity to communicate and send signals that power the brain to complete everyday tasks like reading this article, craving dessert, feeling anxious about a test, or planning your next vacation.

Neurons can either be electrically activated (ON) or inactive (OFF), and the balance between what neurons are ON or OFF determines how the brain will function.

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Manipulating the brain to understand its function

Optogenetics gives scientists the ability to control the activity of specific neurons in the brain, which can ultimately help us figure out how the brain works and treat it.

Imagine you’re a brain scientist who wants to find neurons that are important for hunger. You’ve read that brain cells in an area called the hypothalamus are critical for hunger, but are a bit skeptical about it.

With optogenetics, you can design an experiment to prove these neurons are indeed important for hunger. First, you could turn these potential “hunger” neurons ON to see if that makes an animal more likely to eat. Alternatively, you can turn these neurons OFF to determine if that causes the animal to stop eating. If turning them ON drives hunger, and turning them OFF suppresses hunger, that’s strong evidence that those are indeed neurons critical for the feeling of hunger.

This opens the door for targeting these “hunger” cells later for treating unhealthy eating habits or driving hunger in people who have trouble stomaching food.

Using this logic, scientists have used optogenetics to understand the neural basis for a variety of brain functions.

Researchers have already used optogenetics to:

• Stop aggression in mice by turning OFF neurons linked to threat detection. Mice that would normally brawl choose not to— even in territorial disputes.

• Trigger reward by activating dopamine cells. Mice will push buttons over and over to get a hit of light onto these “feel-good” cells.

• Suppress pain responses by silencing neurons in brain regions involved in processing pain signals.

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How do we make neurons sensitive to light?

The thing is, the brain is famously difficult to access because it is locked in the protective casing of the skull. Also, human brain cells aren’t automatically sensitive to light, and can’t respond to optogenetics on their own. To access the brain, we drill tiny holes in the skull. And to make neurons light-sensitive, we must first insert DNA (borrowed from light-sensitive algae!) into the neurons in the brain to reprogram them.

Drill and inject: using viruses to reprogram cells

You may know viruses as pesky bugs that infect cells throughout the body and make you sick— but did you know a virus does this this by physically entering your cells and replicating, making more and more of itself until it can break free of the cell and find another cell to take over?

Scientists took advantage of this natural biological process by packaging some lab-made “designer DNA” into the genes of a virus. This causes the virus to deliver that designer DNA to the cells it infects. After drilling a hole in the skull, we can inject viruses into brain tissue, causing neurons to take up this designer DNA and become light-sensitive. Then, a laser implant is inserted into the hole in the skull so the light can be delivered straight from a computer to the brain cells.

When the light hits the genetically modified neurons, it either activates them or silences them, which impacts an animal’s behavior.

It’s like we built a brain remote control.

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This Is Huge for Medicine

Optogenetics isn’t just a neuroscience party trick. It’s changing how we understand the brain— and opening the door to precision medicine.

Consider drugs like opioids (fentanyl, oxycodone, morphine, etc). They’re powerful painkillers, but they affect the entire body, leading to harmful side effects like addiction, drowsiness, and respiratory failure.

With optogenetics, scientists can theoretically shut down ONLY pain-related brain cells, without touching cells that control breathing or emotion. This lets them test safer ways to block pain, right at its source.

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Can We Use It in Humans?

Not quite yet…at least not widely. Implanting an optogenetic laser in the brain requires an invasive brain surgery, and it’s still hard to deliver light deep into the brain safely without destroying other neurons in the process.

But there have been real breakthroughs! In 2021, a blind man regained partial vision thanks to optogenetics. Scientists programmed the cells in his eyes to respond to light, then used specially designed goggles to trigger those neurons to turn ON. For the first time in years, he could see shapes and movement!!

Other gene therapies— like CRISPR and AAV-based treatments— are already in clinical trials for brain disorders like Parkinson’s, epilepsy, and rare genetic diseases. Optogenetics is part of that same wave of innovation, with companies working to bring it to the clinic.

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The Future of Mind Control

Optogenetics isn’t perfect. Brain implants and drilling into the skull still pose serious risks. Also, light doesn’t reach every cell or effect each cell the same exact way. But the fact that we can use this technique this now, and that scientists have been using light to control animal’s minds for YEARS is stunning.

We’ve gone from observing the brain to directly manipulating its activity.

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We’re not mind-controlling humans yet (thankfully), but the tools we’re building today could help treat brain diseases in ways drugs never could and help us further understand how our minds work.

I remember back in college in 2018 when I first learned about optogenetics. It was so fascinating to me that it solidified my decision to pursue a PhD in neuroscience. Now I am one year away from my degree! And I have since incorporated this technique into part of my PhD work, contributing to a project that used optogenetics to activate “pleasurable touch” neurons in the skin!

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References:

1. Optogenetics restores vision: https://www.pittwire.pitt.edu/pittwire/features-articles/first-time-optogenetic-therapy-partially-restores-patient-s-vision

2. Sahel, J. A., Boulanger-Scemama, E., Pagot, C., Arleo, A., Galluppi, F., Martel, J. N., Esposti, S. D., Delaux, A., de Saint Aubert, J. B., de Montleau, C., Gutman, E., Audo, I., Duebel, J., Picaud, S., Dalkara, D., Blouin, L., Taiel, M., & Roska, B. (2021). Partial recovery of visual function in a blind patient after optogenetic therapy. Nature medicine, 27(7), 1223–1229. https://doi.org/10.1038/s41591-021-01351-4

3. Boyden ES. A history of optogenetics: the development of tools for controlling brain circuits with light. F1000 Biol Rep. 2011;3:11. doi: 10.3410/B3-11. Epub 2011 May 3. PMID: 21876722; PMCID: PMC3155186.

4. Optogenetics for pleasurable touch neurons: https://zuckermaninstitute.columbia.edu/origins-pleasurable-touch-traced-skin-brain-mice#:~:text=Neurons%20that%20project%20to%20the,for%20pleasurable%20touch%20in%20mice.