Caplan & Waters propose a dedicated linguistic working
memory to handle “interpretive” language comprehension,
but there are data suggesting that more general working memory
capacity can predict syntactic comprehension difficulty, and their
claims depend on the existence of a principled distinction between
“interpretive” and “post-interpretive”
processes, which seems unlikely. Other conceptions of the source of
individual differences also deserve consideration, as more flexible
explanations of the phenomena.