Anil Seth writes:

In 2022 we will see brain organoids displaying dynamics that bear comparison with the complex activity patterns indicative of consciousness in humans. This will require us to rethink what counts as a brain signature of “consciousness” and will raise serious ethical issues about brainlike structures grown in the lab.

Brain organoids are tiny, lab-grown bundles of neurons, derived from human stem cells, that display various properties of the developing human brain. In medicine, they provide much-needed biological models that enable us to research conditions, such as Zika-induced microcephaly, that affect brain development.

Brain organoids are also valuable for basic neuroscience research. There is much to be discovered about how the brain bootstraps itself into existence from its underlying genetic instructions and about how, once built, its circuitry supports the complex activity patterns which underlie brain functions. Organoids provide a window onto developing neural circuitry that can be observed and manipulated at will.

A big question that looms large as this research continues into 2022 is whether brain organoids can be “conscious.” After all, they are made out the same basic material as human brains—neurons—rather than the silicon logic gates of AI.

There are already intriguing signs that some building blocks may be in place. In 2019, Hideya Sakaguchi and her colleagues at the University of Kyoto showed distinctive “spiking” activity in neural networks derived from organoids. Even more strikingly, Alysson Muotri and his team at the UC San Diego have found that brain organoids show waves of coordinated electrical activity, not unlike the patterns seen in human infant brains before birth. [Continue reading…]