The Conservation Task of Linguistics?

The Barner reading discusses how young children struggle to interpret scalar words like "some" because they can't distinguish them from other scalars like "all."  One explanation of this phenomenon is that the children don't put forth the "processing power" to consider alternate scalars that could better describe a situation.  The results of Barner's study were consistent with this explanation:  Even the addition of the word "only" in front of "some" didn't cause kids to reject the word "some" in situations where "all" would've been more appropriate.  The Stiller reading also explores how children interpret scalars, though Stiller's experiments used pictorial cues to establish the difference between none (just a face), some (a face with glasses), and all (a face with glasses and a top hat).  Stiller's experiments also focused on even younger children (preschool-aged) and sought to validate or invalidate the counterfactual and linguistic alternatives theories.  Stiller found that preschool-aged children do in fact have the foundations for scalar implicature and went on to conclude that children learn the difference between words like "all" and "some" by acquiring real-world knowledge.

Both readings discuss how children have trouble differentiating between scalars, particularly "some" vs. "all."  Barner used a more conventional approach (sentence picking) to study this phenomenon, while Stiller used a logically equivalent but seemingly novel approach (image picking based on different facial features).  The Barner reading also focused more on explaining why children are worse than adults at this task, whereas the Stiller reading focused on using the information that children are worse at this task to answer broader questions about linguistic theory.

These two papers remind me of the conservation task experiments I learned about in Psych 1.  The basic idea behind these experiments is that when you pour liquid from a short, fat glass into a tall, thin glass in front of a young child, the young child will think that there's more liquid in the tall, thin glass (even though the same amount of liquid was in both glasses).  Like with the "some" vs. "all" phenomenon, young children certainly understand the difference between "less" and "more."  They just don't devote the cognitive resources to deducing that the taller height of the liquid in the tall glass doesn't necessarily mean that there's more liquid in it.  Conservation tasks and linguistic pragmatics certainly seem very different on the surface, but I wonder whether the lack of development of same mechanism within the brain (perhaps the temporal lobe) can explain both of them.  If so, then perhaps psychologists could benefit even more from linguists than they currently do in trying to understand how the brain works.