Priming sentence comprehension in aphasia: effects of lexically independent and specific structural priming

ABSTRACT

Background & Aims: Impaired message-structure mapping results in deficits in both sentence production and comprehension in aphasia. Structural priming has been shown to facilitate syntactic production for persons with aphasia (PWA). However, it remains unknown if structural priming is also effective in sentence comprehension. We examined if PWA show preserved and lasting structural priming effects during interpretation of syntactically ambiguous sentences and if the priming effects occur independently of or in conjunction with lexical (verb) information.

Methods & Procedures: Eighteen PWA and 20 healthy older adults (HOA) completed a written sentence-picture matching task involving the interpretation of prepositional phrases (PP; the chef is poking the solider with an umbrella) that were ambiguous between high (verb modifier) and low attachment (object noun modifier). Only one interpretation was possible for prime sentences, while both interpretations were possible for target sentences. In Experiment 1, the target was presented immediately after the prime (0-lag). In Experiment 2, two filler items intervened between the prime and the target (2-lag). Within each experiment, the verb was repeated for half of the prime-target pairs, while different verbs were used for the other half. Participants’ off-line picture matching choices and response times were measured.

Results: After reading a prime sentence with a particular interpretation, HOA and PWA tended to interpret an ambiguous PP in a target sentence in the same way and with faster response times. Importantly, both groups continued to show this priming effect over a lag (Experiment 2), although the effect was not as reliable in response times. However, neither group showed lexical (verb-specific) boost on priming, deviating from robust lexical boost seen in the young adults of prior studies.

Conclusions: PWA demonstrate abstract (lexically-independent) structural priming in the absence of a lexically-specific boost. Abstract priming is preserved in aphasia, effectively facilitating not only immediate but also longer-lasting structure-message mapping during sentence comprehension.

KEYWORDS:

• Structural priming
• aphasia
• sentence comprehension
• implicit learning
• syntactic ambiguity

Acknowledgments

We thank our participants with aphasia and their caregivers for their participation and Grace Man and Hannah Haworth for their assistance with data collection.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

1. The adaptation account (Jaeger & Snider, 2013) also accounts for fast decay of lexical boost. Interlocutors are aware that the dense informativity of lexical material would disappear once a new topic is discussed. Thus, the ephemeral lexical boost effect is caused by comprehenders’ sensitivity to this fast decaying nature of lexical distribution in their linguistic environment.

2. In Experiment 1, an additional 2.1% of the data were removed for each group due to extreme response times. In Experiment 2, an additional 2.4% and 2.3% of the data were removed for HOA and PWA, respectively.

Additional information

Funding

This work was in part supported by National Institues of Health grant R21DC015868 (Lee)