Textbook Group meeting for Parr, Pezzulo, Friston 2022 .

Okay, hello, it's September 16th, we're in Cohort 1 of the Active Textbook Group, it's meeting 15, or I guess, yes, no, 16, on, let me just update the title, meeting 16, we're in our second discussion on Chapter 6. So, are there any overall comments that people would like to address about Chapter 6? Or any other questions or points to add, or just areas of Chapter 6 that they found to be interesting? Distinction between the interceptive-extraceptive modalities, which have been mentioned in Box 6.1. And first, I think, Pristen, with Michael Allen, if I'm not mistaken, has published a recent paper just today, exactly on that topic, in which they've somehow tried to provide a computational model for the first time, for the unification of the interceptive and extraceptive modalities. So, since this chapter is also about the modeling of those agents, I think this paper from the, in the body's eye, the computational anatomy of interceptive inference might be relevant for anyone who wants to model these modalities, with the aid of active inference framework. Thank you. Very nice. Thanks for sharing it. Let's look at Box 6.1. As people see it, what distinguishes exteroceptive, proprioceptive, and interoceptive modalities? For example, why are proprioceptive and interoceptive separated? Because I couldn't hear you. I don't know if it's on my side or connection was unstable from your side. Sorry. Let me try something. I'll be gone for a second. Am I back? Okay. So, yeah. What? Yeah, Brock, I do need the star link. Why are proprioception and interoception separated? And why are these three categories modeled as different? Why have they been framed as different? Why do they be framed as different from our body? Why do they be framed as different from our body? Why do they be framed as different from our body? biological and neurological mechanisms and neural mechanisms that somehow can control those different kind of perceptions because for the extra septic perception the organism would necessarily need a kind of sensory I mean the sensation it gets from the environment is just on the level of its of the imminent stimuli that it gets from the external environment but for the interceptive modality the sensation is just the internal sensations and so on and for the pre-preceptive it's related to motor control feedback loop so I guess because of their different mechanisms it might be helpful to talk in different terms about each of them but I'm not totally sure about that I agree I think one aspect even in a pre-blanket or non-blanket modality is like they're about external things versus about internal things and then between proprioception and interoception you're absolutely right that they have different neural mechanisms and physiological mechanisms um with some blurry space perhaps for example like interoception about blood pressure is somewhere in between like a muscular reflex and uh uh an organ reflex but the tissues being addressed are different um let's look at this paper again we'll we'll return to the book but we're going to be thinking today and then especially going forward with like how do you identify the um let's go to this question which we just just to look at it which system are we modeling what is the appropriate form for the generative model how do we set up a generative model how do we set up a generative process so let's see if we can determine some of those aspects in this paper hashtag figure 4-3 it is the very same okay this is just a general pointing to a partially observable Markov decision process with with with a slight um plus computational biology graphical veneer to match the color scheme probably not but but it kind of looks like it here is where we see the schematic of the form of the generative model variable. Variables are used to reflect that those variables can be fit from empirical data or just a priori set and simulated, but this is the form of the model. These are the shapes of the matrices and…