A prosódia como marca de segmentação discursiva baseada em eventos: um estudo de percepção com rastreamento ocular

Abstract

In this study, we investigated the role of prosody in processing the organization of event structures in narratives read aloud. Different theoretical models describe discourse structure as a hierarchically organized product. Among those models, in this research, we adopted event cognition theory to explain the internal organization of narratives read aloud by a journalist. According to that theory, the discourse units that constitute a narrative are understood as events—goal-oriented actions situated in time, with a beginning and end, occurring in specific settings, and involving people and objects. Over the past decades, prosody has been attributed an important function: its various elements, such as pauses, intonational movements, and segment lengthening, tend to be used in segmenting the units that compose discourse, serving as cues for its hierarchical organization. Accordingly, we established two hypotheses: (i) specific prosodic features mark the boundaries of events in oral narratives; and (ii) these specific prosodic features allow listeners to anticipate an imminent event boundary in the informational flow. To test the first hypothesis, we prepared 30 narratives, each with two versions (one containing an event boundary and one without), which were recorded in an acoustic booth. These narratives were segmented into intonational units by two experienced researchers. We analyzed acoustic measures of fundamental frequency (F0 variation and reset),duration, and intensity of tonic syllables adjacent to prosodic boundaries coinciding and not coinciding with event boundaries, as well as the occurrence and duration of silent pauses at these boundaries. The acoustic data were subjected to parametric and non-parametric statistical tests, considering results significant at p < .05. To test the second hypothesis, we conducted an eye-tracking experiment using the auditory paradigm on the Gorilla Experiment Builder platform, involving 20 participants.Volunteers listened to the narratives in both experimental conditions while observingtwo character illustrations on the screen. Eye-fixation proportions on each illustration were analyzed across three time windows: pre-boundary, critical, and post-boundary. The critical window was central to the analysis, as it hypothetically captured the prosodic cues indicating the transition to a new narrative event. The results, although not statistically supported, showed that the elements of F0 variation, F0 restart, intensity and duration of silent pauses tend to corroborate what previous literature has reported about the role of prosody in the structure of spoken discourse. As for the second hypothesis, the results of the experiment suggest that speech processing may actually depend on a more complex confluence of linguistic factors, including prosodic and segmental suprasegmental information. We recommend replicating this study with spontaneous narratives, a larger linguistic data sample, and other online experimental techniques to test the hypotheses in different contexts and expand our understanding of the role of prosody in discourse organization of Brazilian Portuguese.