Implicit metric structure in aprosodic productions of The Cat in the Hat modulates auditory processing
Ahren B. Fitzroy1,2 & Mara Breen1
1Department of Psychology and Education, Mount Holyoke College, South Hadley, MA; 2Department of Psychological and Brain Sciences, University of Massachusetts, Amherst, MA

Poster presented at the 60th annual meeting of the Psychonomic Society, Montreal, QC (2019)
(for reprint, contact ahren.fitzroy@gmail.com)

Audio examples:
Synthesized Cat In the Hat excerpt, normal order


Synthesized Cat In the Hat excerpt, random order

Abstract:
Strong, clear metrical structure is a common feature in children’s literature across languages and cultures. The temporal predictability afforded by this structure may support the putative benefits to literacy acquisition of such works; because early children’s literature is usually heard before it is read, predictive temporal cues allow preparatory cognitive activity to facilitate processing of predicted auditory information. Metric structure in music is known to guide auditory temporal attention in this way, leading to enhanced auditory processing of metrically strong sounds. We have recently demonstrated that metric structure in The Cat in the Hat is realized in word duration and intensity during child-directed reading, providing the temporal cues needed to guide auditory temporal attention. It is unknown however, whether such metric structure in speech guides auditory attention in either children or adults in the same manner as music. 

To investigate this issue, we employed event-related potentials (ERPs) to assess the implicit prosodic realization of predictive temporal structure during perception of aprosodic synthesized productions of The Cat in the Hat in adults. The synthesized productions were isochronous, had flat fundamental frequency, and did not vary in intensity between words. The synthesized productions were presented in canonical and pseudorandom order to 24 young adults, and ERPs to word onsets were generated separately for each beat in a 6/8 metric structure. A late negativity (330 – 475 ms) was observed in response to the metrically strong beats (1 and 4) of the measure, similar to previous investigations of metric attending in musical contexts. This effect was evident only when the words were presented in canonical order, suggesting the effect reflects parsing of implicit metric structure. Additionally, preliminary source localization analyses suggest early evoked activity in primary auditory cortical regions was modulated by beat position only when the words were presented in canonical order. These results demonstrate that processing implicit metric structure in speech relies on neurocognitive mechanisms also involved in processing explicit metric structure in music. Further, in light of previous work demonstrating acoustic realization of 6/8 metric structure in child-directed readings of The Cat in the Hat, these results suggest that child-directed reading emphasizes grouping structures similar to those automatically generated by mature neuroperceptual systems during online processing of the same linguistic content.

References:
Astheimer, L. B., & Sanders, L. D. (2009). Listeners modulate temporally selective attention during natural speech processing. Biological Psychology, 80(1), 23–34. https://doi.org/10.1016/j.biopsycho.2008.01.015
Breen, M. (2018). Effects of metric hierarchy and rhyme predictability on word duration in The Cat in the Hat. Cognition, 174, 71–81. https://doi.org/10.1016/j.cognition.2018.01.014
Dr. Seuss. (1957). The Cat in the Hat. New York, NY: Random House.
Fitzroy, A. B., & Breen, M. (2019). Metric structure and rhyme predictability modulate speech intensity during child-directed and read-alone productions of children's literature. Language and Speech.
Fitzroy, A. B., & Sanders, L. D. (2015). Musical Meter Modulates the Allocation of Attention across Time. Journal of Cognitive Neuroscience, 27(12), 2339–2351. https://doi.org/10.1162/jocn_a_00862
Jusczyk, P. W., Houston, D. M., & Newsome, M. (1999). The Beginnings of Word Segmentation in English-Learning Infants. Cognitive Psychology, 39(3–4), 159–207. https://doi.org/10.1006/cogp.1999.0716