Neuroscience
Theory, and Why It's Time Psychology Got One
Psychology has a problem. We have no core theory to guide our research; no analogue to the theories of evolution or relativity. When particle physicists recently found that some neutrinos had apparently travelled faster than light, it never actually occurred to them that this is what had happened. On the basis of the extraordinarily well supported theory of relativity, everyone went 'huh, that's weird - I wonder what we did wrong?', and proceeded to use that theory to generate hypotheses they could then test. It would take a lot of fast neutrinos to disprove relativity.
Psychology, though, when faced with an empirical result that violates the laws of physics, can't find any principled reason to reject the result and instead spends a lot of time squabbling about whether Bem's result might possibly be true because 'quantum'. Worse, when people
do replicate the experiment and fail to support the original result, they can't get their 'null result' published. It's a bit embarrassing, really.
One of the problems of having no core theory is that you can't simply rule things out as options. Psychologists almost all consider this a strength: we can pick and choose from a variety of mechanisms which enables us to cope with our messy and erratic subject matter. Can't imagine how perception can explain a result? Just hypothesise a mental representation to fill the gap. After all, no single theory is going to account for the opportunistic and idiosyncratic behaviour of people, so why limit ourselves? We tried that with behaviourism, and it got us nowhere. Let's stay flexible.
The problem with this approach is that psychology has gotten lazy; when you can't come up with a simple solution to your complex problem, you suggest a complex solution that fills all those pesky gaps, and never notice the gaps were a bit weird to begin with (Costall, 1984). Representations can solve everything if they contain the solution, and thus they explain nothing at all. An example of this comes from the prehension literature: when reaching, people accelerate their hands to a peak speed that occurs ~70% of the way through the reach. To explain this stable timing, researchers like Jeannerod postulated motor programmes that simply instructed the system to reach this way; they just took the structure of the reach and placed it in a representation. This explains nothing: the structure in the reach is caused by the structure in the representation, but what caused the structure in the representation? This question got more complicated as it became clear that the details of the temporal structure of prehension emerge in real time as a function of the task; suddenly you needed a different programme for every different situation! The answer actually requires a careful analysis of the affordances of the task (e.g. Mon-Williams & Bingham, 2011). This, however, is hard.
This laziness and lack of discipline leads people to try and combine arguments and mechanisms that simply aren't compatible with one another. Do you like embodiment, but can't see how cognition can occur without representation? Let's have embodied representations! As Louise Barrett's book makes clear, however, this type of approach does nothing but make you miss the
actual embodied solution. Her account of the wonderfully sophisticated behaviour of the Portia spider talks about how people first explained their ability to navigate via detours in terms of 'insight'; they sit and scan their environment and then suddenly move off in the right direction as if they had planned their route. The form of the scanning behaviour itself, however, is critical, and careful experiments that break the information they are looking for have shown that Portia scans and moves according to simple rules that lead to the right solution (like the 'linear optical trajectory' solution to the outfielder problem). Tony Chemero also lays out the fact that embodiment and representations come from irreconcilable schools of thought quite clearly; so not only is it bad science, it's incoherent to begin with. We simply can't keep picking and choosing the easiest explanations; it's time to invest the time and effort required to uncover what's actually going on. It's time to spend some time working within the confines of a real theory.
Theory in ScienceAs I try to teach my students, the role of theory in science is to provide structure to your data. A good theory rules explanations in
and out, and if it rules out the wrong explanation that will become clear over time as you pursue your theory guided research. Good science means a) restricting your explanatory mechanisms to include things your theory allows, and b) keeping an eye on how well that's working out for you, while c) allowing yourself to rest on your well supported theory to resist breaking the rules as long as you can. When creationists say 'we can't see how the chambered eye could possibly have evolved, it's far too complex', biologists are entitled to say 'well, we have evidence that lots and lots of other things have evolved, let's see if we can figure out how the eye did it, and in the meantime, we're going to operate on the assumption that it did evolve until we have strong evidence to the contrary'. No-one except creationists complain about this; it's perfectly healthy science.
In psychology, when Bem publishes a paper that rests on the assumption of information travelling backwards in time, I get told off for simply ruling out his explanation for his data on the basis that a) it's physically impossible and b) 'quantum' isn't a get out of jail free card for (a). According to my anonymous debater, it's bad science to rule things out that don't fit my theories of how things work, because I might be wrong. Yes, I might be wrong: but good hypothesis driven science will eventually reveal this if it is, indeed, the case, and that's what the scientific method is for. I am actually allowed to rest on the well supported theory of relativity that describes why Bem's explanation is is impossible and simply reject the explanation out of hand. This doesn't make me close minded, this makes me a scientist.
If neutrino research actually manages to break relativity,
then I will reconsider; in the meantime, Bem is simply cheating and I'm calling him out for it.
Ecological PsychologyI think the closest psychology has to a decent actual theory of behaviour is Gibson's ecological psychology; this is Chemero's bet too. It proposes very specific hypotheses to explain behaviour; these hypotheses contain suggested mechanisms (specifically, information and affordances) to support behaviour, and suggests ways to empirically test these hypotheses. These tests have been very successful (e.g. my work in coordinated rhythmic movement, and the success of the three key predictions of the perception-action model, not to mention affordance research coming out of everywhere).
Because of these successes, I am able to use this theory to generate predictions about other behaviours like catching a fly ball). There are two ways to achieve a goal related to the future state of things: prediction, and prospective control. The former entails taking the current conditions and using these to predict future conditions, then acting on the basis of that prediction. The latter entails coupling your behaviour to specific aspects of current conditions, and letting the future solution emerge as you engage in perceptually controlled behaviour. The ecological approach rules out the former as an option, and goes looking for evidence of the latter. My work based on this theory will either work or it won't; but at least I'll be able to tell the difference, if my empirical work is theoretically constrained.
The Cost of No Theory Psychologists
hate ruling things out - they just love leaving the door open to 'both solutions are probably used', because they have no particular reason to rule anything out. But this has a huge cost:
psychology becomes a mere collection of empirical results, with nothing tying them together. Results from the different disciplines can't inform each other, because they aren't testing the same things. This is currently most clear to me in the gulf between embodied cognition and cognitive neuroscience. Neuroscience finds computation and representation only because it's looking for computation and representation: no-one is asking non-computational, non-representational questions or interpreting data in that light, so there's nothing in the neuroscience literature that informs my science.
This fragmentation means psychology is doing nothing but running in empirical circles: there's nothing resembling progress. All you get are individuals with their own collection of hunches running their own experiments on their own little experimental phenomena. Psychology needs to pick a side, suck it up and get on with some normal science for a change. Taking embodiment seriously is the first step. Taking perception seriously is the second. Using dynamical systems to describe these things is not a bad idea either. Our empirical successes are mounting, whenever anyone bothers to go looking - Gibson and embodied cognition seem a healthy place to start, because representational approaches simply don't rule anything out and thus can't help.
And the beauty of a period of serious normal science is that if we invest some serious time pushing the theory, looking for cracks, and resisting the temptation to jump ship at the first sign of trouble, we will end up in a better place no matter how it pans out. If the theory breaks, it will have been broken honestly, and for good reasons. If the theory holds up, we will have achieved a lot of progress and begun to act like a real science for a change. This is why the scientific method is awesome: because it works, bitches.
ReferencesCostall, A. P. (1984). Are theories of perception necessary? A review of Gibson's 'The Ecological Approach to Visual Perception'.
Journal of the Experimental Analysis of Behavior, 41(1), 109-115. Download
Mon-Williams, M. & Bingham, G.P. (2011). Discovering affordances that determine the spatial structure of reach-to-grasp movements.
Experimental Brain Research, 211(1), 145-160. Download
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Neuroscience