Evidence for syntactic adaptation, the phenomenon in which readers become
more efficient at processing infrequent structures after repeated exposure,
has been mixed. We examined adaptation to reduced relative clauses using
Fine and Jaeger’s (2016) materials and new materials. Across three studies,
we observed syntactic adaptation when task adaptation was controlled for
using a novel, statistically powerful method. We found evidence for
adaptation to violations of a transitivity bias that also appears to delay
adaptation to subsequent reduced relative clauses in the same sentence.
Finally, by analyzing reading times for each word, we demonstrate that
syntactic adaptation tends to be localized.