> Neuralink?

I was wondering myself what this research was about and how it compares to Neuralink. I'm going to refer to the tech in the paper as Deep transcranial photoactivation. Here's my take from what I know from both techniques:

-- Depth:
Neuralink is currently being tested on the cortical surface (up to roughly 2 mm deep measured from the surface of the brain), but the team has indicated that there's no reason why the technology couldn't be used much deeper in the brain in the future. All the way down to the brain stem. In other words: Neuralink depth: any. Deep transcranial photoactivation depth: 7 mm non-invasive. Any dept invasive. This means that if you want to go "deep brain" in humans (beyond the cortical surface) both Neuralink and Deep transcranial photo-activation are invasive (in contrast to what the title insinuates).

-- Deep transcranial photoactivation is brain write-only. Neuralink is brain read/write. Neurons can be made to emit light (or fluorescence) "upon trigger" as well (I think?), but in that case the read/write tech becomes invasive, because you need to get close enough to the neurons to "sense the light" and light location. Brain-read spatial resolution would probably be lower than what Neuralink can do, especially depth-resolution (Neuralink currently actually measures up to 8 depths per probe spread out over a depth of about 2 mm if I'm not mistaking).

-- Deep transcranial photoactivation targets all neurons of a specific type (regardless of location). Neuralink works on any type of neuron in a specific desired location.

My conclusion:

-- Deep transcranial photoactivation is going to be useful in academic neurobiology research on animals. The depth is enough to reach any brain region in small model animals such as mice or smaller. It'll make some research faster, cheaper and more advanced to do.

-- Deep transcranial photoactivation will probably help advance synthetic virus tech (designing and putting custom payloads into biological viruses with the goal to edit cell machinery and/or genetics).

-- Use of Deep transcranial photoactivation in humans is probably 10+ years out at least? Use in humans would involve human clinical trials, because we're talking about injecting virus into a human to go into neurons and modify them. It might require separate clinical trials for each type of neuron you'd want to stimulate. I'm estimating Neuralink is way closer to real life (medical) use on humans. I'm estimating some 5 years out tops.

-- I personally can't see where deep transcranial photoactivation has any real-life practical advantages over Neuralink tech for use in humans. Especially in the shorter term. In the longer term it may be useful to treat some human conditions that involve the cortical surface only. Anything deeper or anything that requires read-back Neuralink wins.

Disclaimer: I'm just an electronics / embedded guy with curiosity in neurobiology and BMI's. Correct me if I'm wrong. I'm here to learn. I wish I could work in this field :P

PS: is anybody working on research that experiments with interfacing biological neurons to chips that allow the brain and chip to grow into each other? It would be cool if you could somehow have axons grow to and from such a chip.