Explaining the lack of priming with ungrammatical primes in study 5a

Earlier, we suggested that adults might find sentences in which there is conflict between the prime structure and the prime verb’s identity

unexpected. We also proposed an alternative idea: that the activation of the relevant dative representation might be independent of the verb in that prime. In other words, it might be the syntactic structure of the prime that is

important in the activation of representations for structural priming, and not the links between this structure and individual verbs. Our results, however, were not consistent with either of these hypotheses, and instead fit with the third prediction that we made: that ungrammatical sentences do not activate the appropriate dative representation.

These findings conflict with recent results reported by Ivanova et al. (2012) who found that adults who were presented with ungrammatical DOD sentences with non-alternating verbs could be primed to produce DOD responses with alternating verbs. One reason for the disparity between Ivanova et al.’s findings and ours, could, of course be due to differences in study design. For example, the stimuli across the tasks were different: In our study, non-alternating verbs included both DOD- and PD-only verbs,

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Chapter 5 study, all primes were paired with equi-biased target verbs, but in their study,

the syntactic preferences of the alternating target verbs, although

acknowledged by the authors, were not considered in the interpretation of the results. For example, half of the alternating target verbs in their task (show, chuck, loan, offer) are biased towards the DOD (The British National Corpus, 2007); if the bias of the target verb matches the structure of the prime, then participants might appear to show an increased tendency to echo the syntax of the prime when they are simply responding to the bias of the target verb (which happened to be the same as the prime structure). The methodology between the two studies also differed: The adults in our study took turns in repeating primes and producing target descriptions with an experimenter, whilst in Ivanova et al.’s task, adults read (and did not

produce) prime sentences on a PC monitor, and described target pictures via a headset microphone which recorded their responses.

Nonetheless, the conflicting results mean that we have arrived at conclusions about the way in which adult representations are linked to the verb lexicon that are different to those made by Ivanova et al. (2012). They suggest that even when the prime verb is ungrammatical in its structure, the structure of the prime is enough to activate the appropriate DOD

representation. However, the fact that adults in our study showed structural priming when the prime verb was grammatical in its structure (study 5b), but not when there was conflict between the prime verb and its structure (study 5a) indicates that it is not simply the structure of the prime that is important for the activation of DOD and PD representations: the compatibility between prime verb identity and prime structure matters too. Our findings also allow

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Chapter 5 us to posit a theory about why the ungrammatical sentences did not activate

the relevant dative representations to result in significant structural priming; adults may have found the ungrammatical sentences difficult to understand, forming only representations that were “good enough” for the task (Ferreira, Bailey, & Ferraro, 2002). These representations may have allowed them to produce a dative description of a target image, but may not have included enough detail about whether this structure was a DOD or a PD. Taken together, our findings not only have implications for our understanding about how syntactic representations are stored, but they also provide insight into how the information that we interpret affects how these representations are activated.

5.8. Study 5b: Conclusion

Previous research on adults has indicated that adults are sensitive to prime surprisal such that they are more strongly primed when the bias of the prime verb is unexpected in its structure (Chang, Dell, & Bock, 2006). However, we have found it hard to replicate this effect in adults. In study 3b in chapter 3, we found that adults showed weaker surprisal effects than did children, which we interpreted as suggesting that children have faster learning rates; faster learning rates lead to more substantial weight changes in response to error, and thus more prime surprisal. However, before drawing this

conclusion we wanted to explore whether the results could be attributed to adults’ increased familiarity with the prime verb. To explore this idea, we presented adults with sentences that adults might find more unexpected: sentences with verb-structure mismatches containing low frequency verbs

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Chapter 5 (study 4a), and sentences with verb-structure mismatches containing non-

alternating verbs (study 5a). In both studies, we failed to increase the size of the prime surprisal effect in adults. Our original conclusion, then, stands; adults seem to show smaller prime surprisal effects than children.

The findings from the current study also suggest that the structure of the prime alone is not enough for the activation of the relevant syntactic representations that are needed for successful priming: knowledge about verbs also plays a role. In particular, our findings indicate that knowledge about verbs and their argument structure constraints guides the

interpretation of sentences and influences how syntactic representations are activated. Thus, our findings again support the idea of a close integration between adult syntactic representations and the verb lexicon.

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Chapter 6

Chapter 6

The effect of verb semantic class on structural priming in children and adults

6.1. Study 6: Introduction