So this is definitely a bit of topic shift from our previous readings, but I think it's very useful to see how the analysis-by-synthesis (AxS in Bever & Poeppel's terms) idea is being thought about by people who care very much about the biological underpinnings of language (they are writing for Biolinguistics, after all). The part that spoke most to me was the syntactic section - for one thing, the demonstration of how difficult the mapping can be from syntactic form to meaning (example (4)) was very clear. A main question that arose was whether grammatical derivations are computed as part of the processes of comprehension - this has strong connections to syntactic theory, which views grammatical derivations as the basic operation that has to happen.
Something else of note, which I'd like to think more about, is how to connect the description of AxS that they have here to how we've been thinking about it in the Bayesian models we've looked at already. It almost seemed like some of the distinctions B&P were making were almost orthogonal to how I normally think of a Bayesian model. For instance, in example 9, they deal with the distinction between habits accumulated via induction over experiences (which they seem to liken to pattern recognition) and novel computation (which is presumably the generative part). Mapping this to the Bayesian reasoning stuff we've been looking at, the habits accumulated from induction works pretty well as the general inference from data; would the novel computation then be what happens when the Bayesian learner tries to deal with novel data? But B&P seem to be thinking of this as a process (or processes) that apply during language comprehension, so is all of it happening when the novel data is encountered during comprehension?
Later, in section 7, where they move to AxS in visual perception (and in particular visual object recognition), they again seem to have the division into the quick heuristic/pattern recognition and the slower computation. Would we view this as a two-step inference process when the novel data point is encountered? Step 1: update prior based on quick heuristic ==> new posterior; Step 2: update new posterior based on slower computation ==> newer posterior. The same sort of question would apply when we talk about AxS for sentential meaning (section 8.3): the quick heuristic is the literal meaning, while the slower computation is the pragmatic knowledge.
They do touch on applying this to acquisition at the very end of the article - how the child builds up statistical generalizations over time, with the example of learning the canonical sentence form. The interesting part is that the novel computation is triggered by noticing that there's not a one-to-one mapping from form to meaning all the time. Does this make any clear acquisition trajectory predictions? It seems like it might have something to say about children's understanding of this mapping, and how many non-canonical forms they've seen. But maybe sometime more concrete can be said?