By the time I finished graduate school, reddit was dead so I never bothered getting verified on the Science subreddits. It was a bummer!

I’ll be the pedant no one asked for - the sodium and potassium channels in the neuron respond to voltage changes in the membrane, so the author isn’t wrong.

Action potentials are generated when dendritic (input) channels bind with neurotransmitters like glutamate and GABA released by the axon terminal (output) of the pre-synapse cell. When these channels open, the let in ions like Calcium, Sodium, and Chloride.

These ions change the electric potential across the cell membrane, once this passes a key threshold, the sodium channels in the rest of the cell open up and generate an action potential. It’s driven by ions with electric charge (electrochemical).

Not quite, an iron lung replaces a dysfunctional organ. I’m saying we can already grow neurons onto circuits, and it’s difficult (not impossible) to implant neurons into a body. I don’t easily see how these bio-engineered neurons make those processes easier.

Credentials: I published in this field, but I don’t have time to read the entire paper right now.

This is exciting work. Based on the key highlights, it sounds like their work focuses on how plausible it is to construct the bio-artificial neuron, and they have done so with great success.

What I would like to learn about is what advantages this technology has compared to just cultivating neurons on a microelectrode array. Are the artificial cells easier to maintain? Do they interface with electrodes without developing glial scarring like our brains do? Can they bio-engineer special proteins (e.g. optogenetic channels) easier in these cells than in mouse lines?

The discussion section is fairly anemic. The authors say this will “spearhead” additional development but I was disappointed the authors didn’t clarify what will be additionally developed.

Until these advantages are spelled out, it feels like we’re re-invented the biological wheel. We already have cells that can integrate and fire at low voltages. They’re called neurons. Why did we need artificial ones?