2024 Utah-array work: neural basis + jackpot collapse

1:19:00um now let's go to this next paper that this was from Smolder um and other authors in 2024. This was in Neuron, a neural basis of choking under pressure. And what a title >> for a [laughter] paper. Can I just say >> um here's what they did. They used they um they used 96 channel Utah arrays in reus macaks. So, Macaks have a prefrontal cortex kind of like we do. >> Um, this was in the motor cortex and in another brain region called PMD >> and they had the similar um behavioral paradigm of choking under pressure. Basically, there were these jackpot scenarios where the monkey knew that if

1:19:40it succeeded, it was going to get a really high reward. And again, the same thing happens. you get this increase in performance, but when you get an incredibly high >> reward anticipation, your performance decreases. >> So, what we're looking at here is three charts of monkey E, P, and R with six sessions, nine sessions, and 12 sessions. >> And on the Yaxis is success rate and on the X-axis is sort of jackpot size from small going to large. And you can basically see this like top of a trapezoid. >> Yeah. where we have at small to medium >> there's an increase >> there's a huge increase and then medium to large it kind of maintains at that higher level success rate and you see a

1:20:23very drastic decrease in performance when you move from large to jackpot across all these session lengths and all of these different subjects >> and so regardless of number of repeats etc etc there's a clear decrease in performance efficacy when the jackpot gets sufficiently high >> yeah and the jackpot is way higher than The large is the other big thing. It's like small, medium, large are like successively higher, but jackpot is like an actual jackpot. And that's kind of what the Olympics are in some sense, right? Like the stress is so high and that gold medal that's like sitting there could be yours. It's it's incredible, right? And so how how do we

1:21:03manage that? And so okay, >> we we saw the behavioral paradigm which is the same as we have have in humans. The trick is now we want to find a neural paradigm, something in the neurons themselves that correlates to that behavioral paradigm because then we found a neural signature for what is happening. Yes. Right. >> They use something called dimensionality reduction. This is something that we've been through in neuroscience. The idea is your brain lives in a very highdimensional subspace. Right? If you're if you're listening to 10,000 neurons, that's 10,000 different dimensions in your mathematical sub subspace of where your brain is. >> Your brain doesn't actually live in that

1:21:44subspace. That's just how we're describing it. There might be lower dimensions that we can move along that tell us something about, oh, how much does the brain care about reward in this scenario? How much does the brain care about the target getting to the target and getting that reward in this scenario? Right? We can decompose the brain activity into independent metrics and see what happens. So what they found was in the reward axis there was an axis that like basically correlated with reward. Okay? So when it was jackpot it was really high. There were a bunch of neurons that were firing when it was a