Exploring the Similarity Between Implicit and Explicit Prosody: Prosodic Phrasing and Individual Differences

In recent years, work carried out in the context of the implicit prosody hypothesis (IPH) has called into question the assumption that implicit (i.e., silently generated) prosody and explicit (overtly produced) prosody are similar in form. Focusing on prosodic phrasing, the present study explored this issue using an individual differences approach, and using methods that do not rely on the sentence comprehension tests characteristic of work within the IPH program. A large group of native English speakers participated in a production experiment intended to identify individual differences in average prosodic phrase length, phonologically defined. We then explored whether these (explicit) prosodic differences were related to two other kinds of variation, each with a connection to implicit prosody. First, we tested whether individual differences in explicit prosodic phrase length were predicted by individual differences in working memory capacity, a relationship that has been established for implicit prosody. Second, we explored whether participants’ explicit prosodic phrase lengths were predictive of their behavior in a silent-reading task in which they had to identify their own implicit prosodic groupings. In both cases, the findings are argued to be consistent with a similarity between explicit and implicit prosody. First, participants with higher working memory capacity (as estimated by reading spans) were associated with longer prosodic phrases. Second, participants who produced longer explicit prosodic phrases in speech tended to report generating longer prosodic phrases in silent reading. Implications for the nature of implicit prosody, and how it can be studied, are discussed.

Event-Related Potential Evidence of Implicit Metric Structure during Silent Reading

Under the Implicit Prosody Hypothesis, readers generate prosodic structures during silent reading that can direct their real-time interpretations of the text. In the current study, we investigated the processing of implicit meter by recording event-related potentials (ERPs) while participants read a series of 160 rhyming couplets, where the rhyme target was always a stress-alternating noun–verb homograph (e.g., permit, which is pronounced PERmit as a noun and perMIT as a verb). The target had a strong–weak or weak–strong stress pattern, which was either consistent or inconsistent with the stress expectation generated by the couplet. Inconsistent strong–weak targets elicited negativities between 80–155 ms and 325–375 ms relative to consistent strong–weak targets; inconsistent weak–strong targets elicited a positivity between 365–435 ms relative to consistent weak–strong targets. These results are largely consistent with effects of metric violations during listening, demonstrating that implicit prosodic representations are similar to explicit prosodic representations.