Scientists watch a memory form in the brain of a living fish

In fish...<p>&quot;Contrary to expectation, the synaptic strengths in the pallium remained about the same regardless of whether the fish learned anything. Instead, in the fish that learned, the synapses were pruned from some areas of the pallium — producing an effect “like cutting a bonsai tree,” Fraser said — and replanted in others.&quot;<p>This is a very counter intuitive. So there are existing neural connections (formed somehow previously...) and new memories form by pruning these connections? Crazy

&gt;While a developing mammalian brain grows by just getting bigger — “inflating like it’s a balloon” — the zebra fish brain almost turns itself inside out “like a popcorn kernel, so those deep centers are up near the surface where we can image them.<p>Makes me wonder: How big is the hidden cost of destroying rain forests and other habitats? Every species that we lose is the loss of genetically encoded knowledge that could be very useful at some point.<p>Could we protect the environment by making investment fonds eligible to the profits from genetic knowledge on the territory they own?

Super cool, they added fluorescent proteins that activate when the neurons fire and did it in a Zebrafish which is transparent so they could literally watch the memories forming. Interesting also they wanted to keep the light as low as possible to not scorch the little guys.

I&#x27;ve always wondered if the fluorescent markers are visible to the fish and whether that might change their behaviour during experiments especially if it is a group interaction with other specimens who are not similarly modified.

That doesn’t sound much like memory formation though, per se. Sounds more like adaptation &#x2F; improved emotional regulation, which (less surprisingly) requires major rewiring.

<a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Synaptic_pruning" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Synaptic_pruning</a>

I&#x27;m more concerned about the mechanism current memories being modified in actual developed cognition, regardless of age&#x2F;location. Does it pass the &quot;sniff test&quot; if animals can&#x27;t distinguish the difference?

Why didn&#x27;t they try to create a good memory too, just to see if there appeared to be a difference in how it was created or stored?

Looks super cool. I read about Neural Pathways in grad school, and seeing all that theory in action feels great.

Very nicely done. This is great research. Technical, creative, and substantive. Congrats to the whole team.