Thursday Things: Brain In A Jar Edition

20 October 2022. Vol 4 No 42 By Dan McGirt. #167

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Eventually the games will play themselves. Photo by YongGuang Tian on Unsplash

Seeing Is Believing

One of the first “research reports” I wrote for school (longhand, on notebook paper, with a ballpoint pen) in maybe the 5th grade or so, was about the human brain.

Granted my ‘research’ consisted of extensive quotes from the Encyclopedia Britannica, but I learned the basic morphology of the brain by writing that paper, along with the virtues of erasable ink. The brain — especially the human brain — has continued to fascinate and amaze me ever since. Not so much that I became a neuroscientist, but I do enjoy reading about what they’re up to.

In particular, findings about neuroplasticity intrigues me — the astounding ability of the brain to constantly “rewire” and recreate itself in response to new environments, new experiences, or in response to damage. The brain is incredibly adaptable to necessity.

This included mouse brains, as seen in today’s item:

The Adult Brain Can Recover Lost Vision

Administering a chemical compound called synthetic retinoids to the retina helped restore brain networks associated with vision and prompted the growth of two times more neurons, effectively restoring vision in adult mouse models of the genetic visual disorder LCA.

As we’ve pointed out before, mice get all the good stuff first. But the hope is that findings in the mouse brain models will be applicable to helping human patients.

“Frankly, we were blown away by how much the treatment rescued brain circuits involved in vision,” said Sunil Gandhi, professor of neurobiology and behavior and the corresponding author. Gandhi is a fellow of UCI’s Center for the Neurobiology of Learning and Memory and a member of the Center for Translational Vision Research.

“Seeing involves more than intact and functioning retinae. It starts in the eye, which sends signals throughout the brain. It’s in the central circuits of the brain where visual perception actually arises.”

Until now, scientists believed that the brain must receive those signals in childhood so that central circuits could wire themselves correctly.

Oh, you silly scientists. Always underestimating the power of the brain.

Working with rodent models of LCA, the collaborators were surprised by what they found.

“The central visual pathway signaling was significantly restored in adults, especially the circuits that deal with information coming from both eyes,” Gandhi said.

In short, a brain that never learned to see, due to a genetic disorder that prevented the formation of the usual circuits for vision processing in childhood, can regain much of that lost (as in never was there in the first place) signaling in adulthood, when given the right help — in this case, a dose of retinoids.

What does it all mean?

“The fact that this treatment works so well in the central visual pathway in adulthood supports a new concept, which is that there is latent potential for vision that is just waiting to be triggered.”

The finding opens exciting research possibilities. “Whenever you have a discovery that breaks with your expectations about the possibility for the brain to adapt and rewire, it teaches you a broader concept,” Gandhi said.

“This new paradigm could aid in the development of retinoid therapies to more completely rescue the central visual pathway of adults with this condition.”

It’s never too late to see the light.

The eyeglasses industry is doomed. You heard it here first. Photo by engin akyurt on Unsplash

Mindless Entertainment

Let’s stick with the brain theme. Video games are sometimes derided as mindless entertainment. Which is unfair, since interactive games involve problem solving, hand-eye coordination, and a number of other mental skills. They may “rot your brain” but I think the bigger threat from too much gaming is to your body from lack of physical activity. (Unless you’re playing one of those VR headset games where you jump around in the virtual world. Then your biggest threat is furniture.)

That said, it turns out you don’t even need an entire brain to master some games. Take the ur-game Pong for example:

WATCH: A Dish of Brain Cells Figured Out How to Play Pong in 5 Minutes

The headline pretty much tells the story here.

How many brain cells does it take to play a video game?

No, really. That's not a joke, and there isn't a punchline. Instead, there's a real actual answer, thanks to a neural network system called DishBrain.

If that game is Pong, the number of brain cells is around 800,000.

While their slow-moving, one-sided strategy for digital table tennis won't see them win any e-sports championships in the near future, it does reflect the potential in fusing living tissues with silicon technology.

This is the first synthetic biological intelligence experiment that shows neurons can adjust their activity to perform a specific task – and, when provided with feedback, can learn to perform that task better.

There’s that neuroplasticity again, ponging away. And — bonus! — it’s that old sci-fi trope, the Brain In A Jar.

DishBrain is a heady mix of neurons extracted from embryonic mice and human neurons grown from stem cells. These cells were grown on arrays of microelectrodes that could be activated to stimulate the neurons, thus providing sensory input.

This is not creepy or vaguely unsettling in any way, right?

As for the implications of this work:

DishBrain might be able to help chemists understand the effects of various medications on the brain, to a cellular level. It might, one day, even help tailor medications to a patient's specific biology, using neurons cultured from stem cells reverse engineered from that patient's skin.

"The translational potential of this work is truly exciting: it means we don't have to worry about creating 'digital twins' to test therapeutic interventions," says Friston. "We now have, in principle, the ultimate biomimetic 'sandbox' in which to test the effects of drugs and genetic variants – a sandbox constituted by exactly the same computing (neuronal) elements found in your brain and mine."

These are exciting and promising possibilities for better treatment of neurologic conditions, drug testing, AI research, and … maybe … better computer opponents in your new video game.¹

Assuming the Brain In A Jar doesn’t turn evil and kill us all, of course…

More here: Neurons in a dish learn to play Pong — what’s next?

Thank you!

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1. Or maybe not. Another article — ‘Pong’ learned faster by brain cells in a dish than AI — emphasizes that “While the mini-brains are not as good at Pong as computer-based AIs,” the video adds, “they do learn faster”. It would take an AI around 90 minutes to learn how to play Pong, but these mini-brains take just five.