Tuesday 5 November 2019

The Task Dynamics of Angiogenesis

In the last two posts, I have laid out the proposal that endothelial cells seem to actively perceive their environments, and set out the details of the argument in favour of explicitly taking an ecological approach to understanding why they do what they do during angiogenesis. It's now time to develop that analysis more explicitly.

To do this, I will apply the 4 questions we proposed in Wilson & Golonka (2013) to the question of the endothelial cell behaviour.  These are
  1. What is the task to be solved? 
  2. What are the resources the organism has access to that might solve the task?
  3. How might these resources get assembled so as to solve the task?
  4. Do organisms actually do what you describe in Q3?
We gave some worked examples of this analysis in the 2013 paper, and have described how it drives my work on coordinated rhythmic movement (Golonka & Wilson, 2012, 2019). This will hopefully serve as another example.

Monday 4 November 2019

Endothelial Cells are Intelligent, Perceiving-Acting Agents

In my last post, I laid out a new project I'm working on about the perceptual life of cells. I spent the day at the Crick Institute recently to move the project forward, and this post is about developing the perception-action analysis in more detail. The goal in this post is to address the first question that needs an answer, specifically, are the cells perceiving-acting agents, or just doing something more mechanical?. In the next post, I will apply our task dynamical analysis to frame the project (from Wilson & Golonka, 2013). 

To cut to the chase, I'm now pretty happy that a perception-action analysis is appropriate at this particular cellular level. I set a high bar for this (mostly by reading Turvey & Carello papers, which should illustrate that height pretty clearly :) but it seems clear the cells are behaving with respect to information, and not simply being buffeted by forces. Applying some key criteria, and resting on the hard work of Turvey & Carello showing that intelligence isn't about brains but about behaviour, I will claim here that Bentley's endothelial cells are agents that exhibit intelligent behaviour, and there is a clear need for a behavioural scale contribution to any explanation of that behaviour.

Tuesday 22 October 2019

The Perceptual Life of Cells

Over the summer, at ICPA 2019, I met a computational biologist called Katie Bentley. She is interested in angiogenesis, the cellular level process of new blood vessel growth. She was at ICPA because she has been developing a more dynamical systems approach to understanding how angiogenesis works. More specifically, her work suggests that the cells involved behave in very active, exploratory ways that are very analogous to the kinds of perception-action systems ecological psychologists study, and she was looking for people to help bring our insights to her work. We've been chatting, and the project of connecting our work is now on the go. 

The basic idea is simple. Mainstream cell biology is currently very gene-centric, in almost exactly the same way as mainstream cognitive science is very brain-centric. Like cognitive science, this has been methods driven - it's been hard to study cells in action, and imaging techniques have been static and structural. In general, when biologists see a cell doing something, the research goes looking for the genes that are making it do that thing. Bentley's work has instead started asking questions about time - how long does something take to happen? How are the component processes organised in time? What happens if that timing is perturbed? She's now in a good position to say that one of the key regulators of the dynamics of angiogenesis is timing, that this timing is not centrally controlled by a genetic clock, and that a temporal perspective should therefore move front and centre of the research on the process.

The analogy between the debates between information processing and ecological accounts of cognition and behaviour are uncanny, and her move is a very ecological one. The question we are now discussing is whether it makes sense to start considering this process as not just a dynamical process, but a perception-action process, which has become an option given her temporal perspective on things. 

In this post I'm going to discuss some of the specific empirical findings reviewed in her paper The Temporal Basis of Angiogenesis, which is a good read even if you aren't a cell biologist. I'm getting ready to go hang out in her lab this week and I'm working on figuring out the best questions to be asking to move this project forward in the best way. Remember, Gibson's theory is about what happens at the ecological scale of organisms like us, and there's no guarantee that it will have much to say about the perceptual life of cells. However, there is definitely enough evidence to make it worth checking out, and that's what I'll be up to for the next little while. 

Monday 7 October 2019

Show Me the TALoN! (Thoughts on Raja & Anderson, 2019)

There is a special issue of Ecological Psychology out with contributions from lots of people (including us) on what a Gibsonian neuroscience might look like. I'll work my way through the papers over the next few weeks - today, we read Raja & Anderson's contribution for our lab meeting, and I wanted to write about where we ended up with this paper. The upshot is that the paper is clear and the basic ideas of neural reuse and Transiently Assembled Local Neural Subsystems (TALoNs) really do match up nicely to the perception-action scale explanations in the ecological approach. However, it's just not yet clear how much value is added to the ecological approach by these concepts; neural reuse is perhaps not that radical a notion, and there isn't yet any good evidence that TALoNs are a good account of actual neural architecture. As a functional level description of an ecological approach to brains, it seems quite nice, but there isn't anything convincing in here that this is actually how brains work. Show me that, then let's see what happens.

Monday 30 September 2019

Can the Free Energy Principle be made ecological? (Bruineberg et al, 2018)

Everyone loves Friston's free energy principle (FEP), and everyone wants it for their own. Not everyone can have it, though (well, at least not if it's going to mean anything) and so there's a spirited fight about who's theory it best fits in the literature. 

Bruineberg, Kiverstein & Rietveld (2018) argue two points in an effort to win the fight for the good guys. First, they want to show that inferential, representational takes on the FEP end up in an unworkable place. Second, they want to show that an ecological/enactivist analysis works much better. Overall I think they take a solid swing at both, so it will be interesting to see the responses this sparks. Here I want to review their arguments.

To unbury the lede, I like this paper a lot. It's really long and repetitive, but in here is an excellent ecological analysis of the free-energy principle that also works to explicitly rule out the competition. I am obviously biased, but their work pointing out the flaws of Hohwy's account all make good sense to me, not least because these flaws show up in all kinds of places in the representational ontology. Hohwy fails for the reason interface theory does, in my view, and it's nice to see separate analyses end up in the same place as me. 

For what it's worth, I am not yet convinced that the FEP is the way we need to go. However, if it ends up being a good idea, Bruineberg et al have done sterling work in showing how we should go about it.