Effects of Verb Overlap on Structural Priming in Dialogue: Implications for Syntactic Learning in Aphasia

Abstract

Purpose Although there is increasing interest in using structural priming as a means to ameliorate grammatical encoding deficits in persons with aphasia (PWAs), little is known about the precise mechanisms of structural priming that are associated with robust and enduring effects in PWAs. Two dialogue-like comprehension-to-production priming experiments investigated whether lexically independent (abstract structural) priming and/or lexically (verb) specific priming yields immediate and longer, lasting facilitation of syntactic production in PWAs. Method Seventeen PWAs and 20 healthy older adults participated in a collaborative picture-matching task where participant and experimenter took turns describing picture cards using transitive and dative sentences. In Experiment 1, a target was elicited immediately following a prime. In Experiment 2, 2 unrelated utterances intervened between a prime and target, thereby allowing us to examine lasting priming effects. In both experiments, the verb was repeated for half of the prime–target pairs to examine the lexical (verb) boost on priming. Results Healthy older adults demonstrated abstract priming in both transitives and datives not only in the immediate (Experiment 1) but also in the lasting (Experiment 2) priming condition. They also showed significantly enhanced priming by verb overlap (lexical boost) in transitives during immediate priming. PWAs demonstrated abstract priming in transitives in both immediate and lasting priming conditions. However, the magnitude of priming was not enhanced by verb overlap. Conclusions Abstract structural priming, but not lexically specific priming, is associated with reliable and lasting facilitation of message–structure mapping in aphasia. The findings also suggest that implicit syntactic learning via a dialogue-like comprehension-to-production task remains preserved in aphasia.

The role of explicit memory in syntactic persistence: Effects of lexical cueing and load on sentence memory and sentence production

“…Taken together, the current findings are consistent with previous studies on the explicit memory processes in structural priming, in that an explicit memory-related process contributes to both lexical-dependent structural priming ( [14,33,36]) and lexical-independent structural priming [29].…”

“…Thus, the validity of this postulated explicit memory mechanism in structural priming was initially called into question (e.g., [28]). Nevertheless, a number of studies provide evidence for the possible involvement of explicit memory in structural priming ( [14,[29][30][31][32][33][34][35][36]). Importantly, several studies demonstrated that some effects of structural priming show characteristics that are analogous to a short-term memory effect ( [14,31,36]).…”

“…Other studies tried to answer a similar question by investigating the effect of structural priming and the lexical boost in people with aphasia ([ 33 , 38 , 39 ]). The basic assumption of these studies is that if lexical overlap functions as a retrieval cue, patients with impaired verbal short-term memory might show more difficulty in maintaining the explicit memory of sentence structure, which should lead to a smaller lexical boost effect in a structural priming task.…”

“…The basic assumption of these studies is that if lexical overlap functions as a retrieval cue, patients with impaired verbal short-term memory might show more difficulty in maintaining the explicit memory of sentence structure, which should lead to a smaller lexical boost effect in a structural priming task. Man and colleagues’ study provided evidence for this assumption: people with aphasia had preserved lexical independent priming but not lexical boost, whether the prime and target were separated by zero or two fillers ([ 33 ], but see [ 38 ]). These findings suggest that at least a lexical-specific effect of structural priming is driven by a mechanism that rapidly decays, which is constrained by the limited capacity of short-term memory.…”

“…Second, the explicit memory hypothesis assumes that the short-term decay of the priming effects is relative to the limited capacity for speakers to maintain syntactic information in explicit memory (see [ 13 , 14 ]). Although some evidence was found in studies on structural priming in people with aphasia (e.g., [ 33 , 38 , 39 ]), no evidence has been gathered regarding whether limited memory capacity constrains structural priming in healthy speakers.…”