Acoustic features drive event segmentation in speech
Résumé
While our perceptual experience seems to unfold continuously over time, episodic memory preserves distinct events for storage and recollection. Previous work shows that stability in encoding context serves to temporally bind individual items into sequential composite events. This phenomenon has been almost exclusively studied using visual and spatial memory paradigms. Here we adapt these paradigms to test the role of speaker regularity for event segmentation of complex auditory information. The results of our auditory paradigm replicate the findings in other sensory modalities—finding greater within-event temporal memory for items within speaker-bound events and greater source memory for items at speaker or event transitions. The task we use significantly extends the ecological validity of past paradigms by allowing participants to encode the stimuli without any suggestions on the part of the experimenter. This unique property of our design reveals that, while memory performance is strongly dependent on self-reported mnemonic strategy, behavioral effects associated with event segmentation are robust to changes in mnemonic strategy. Finally, we consider the effect of serial position on segmentation effects during encoding and present a modeling approach to estimate the independent contribution of event segmentation. These findings provide several lines of evidence suggesting that contextual stability in perceptual features drives segmentation during word listening and supports a modality-independent role for mechanisms involved in event segmentation.