Are all low-pitched syllables perceived equally? - Evidence from German 10-month-olds
Katharina Zahner, Muna Pohl
University of Konstanz
[email protected], [email protected]
Infants exposed to stress-timed languages take stressed syllables as preferred word onsets
(e.g., Bartels, Darcy, & Höhle, 2009; Jusczyk, Houston, & Newsome, 1999). Braun, Pohl, and
Zahner (2014) recently showed that German infants’ perception of stress is modulated by
utterance-level intonation: In a head turn preference paradigm, German 10-month-olds
successfully segmented embedded trochaic units from trisyllabic words in a peak-stressassociation condition ((L+)H*), but failed in a peak-stress-dissociation condition in which the
pitch peak preceded the stressed syllable (H+L*).
In the current study, we investigate whether these results are caused by the frequent
occurrence of high-pitched stressed syllables in the input (Peters, Kohler, & Wesener, 2005)
or by the perceptual salience of high pitch (e.g., Bion, Benavides-Varela, & Nespor, 2011).
To this end, we created a peak-stress-dissociation condition in which the peak follows the
stressed syllable (as in prenuclear rising accents, see Truckenbrodt, 2007, and questions
ending in H%), a pattern that is assumed to be more frequent in the infants’ input.
Another sample of German 10-month-olds (average age: 38.6 weeks, sd = 1.3) were
familiarized with the same utterances as in Braun, et al. (2014). The same passages were
recorded anew by the same speaker, but now the trisyllabic target words (e.g., [la.ˈɡuː.nəә])
were produced with rising intonation contours (L*+H or L*+H%). They did not differ from
the previous target words in terms of pitch range, duration, and vowel quality. The procedure
and the test stimuli were identical to those in Braun et al. (2014): After familiarization with
the passages, infants listened to three repetitions of four test lists (two familiar and two
novel), each containing 15 tokens of trochees that were embedded in the trisyllabic target
words during familiarization (e.g., [ˈɡuː.nəә] from [la.ˈɡuː.nəә]).
Looking times to the four test lists were measured on-line and averaged for novel and
familiar lists for each infant. Preliminary results of 14 infants show that infants looked on
average 8.2s to familiar and 7.8s to unfamiliar test lists. The pattern of the peak-stressdissociation condition in which the peak followed the stress syllable is similar to the less
frequent peak-stress-dissociation condition in which the peak preceded the stressed syllable;
see Figure 1 for looking time differences across intonation conditions.
Our results suggest that German 10-month-olds need to hear stressed syllables with
high pitch in order to perceive them as word onsets. The underlying mechanism appears to be
the salience of high-pitched stressed syllables instead of the frequency with which the
different intonation patterns appear in the infants' input.
95%CI of looking time difference novel vs. familiar (ms)
Figure 1. Difference in looking times to novel and familiar lists in ms. Whiskers denote
95%CI.
2000
1000
0
-1000
peak-stress association
peak-stress dissociation
(peak following stress)
peak-stress dissociation
(peak preceding stress)
Intonation condition
References
Bartels, S., Darcy, I., & Höhle, B. (2009). Schwa syllables facilitate word segmentation for 9month-old German-learning infants. In J. Chandlee, M. Franchini, S. Lord & G.-M.
Rheiner (Eds.), Proceedings of the 33rd Annual Boston University Conference on
Language Development (Vol. 1, pp. 73-84). Somerville, M.A.: Cascadilla Press.
Bion, R. A. H., Benavides-Varela, S., & Nespor, M. (2011). Acoustic markers of prominence
influence infants' and adults' segmentation of speech sequences. Language and
Speech, 54, 123-140.
Braun, B., Pohl, M., & Zahner, K. (2014). Speech segmentation is modulated by peak
alignment: Evidence from German 10-month-olds. Proceedings of the 7th
International Conference on Speech Prosody. Dublin, Ireland.
Jusczyk, P. W., Houston, D. M., & Newsome, M. (1999). The beginnings of word
segmentation in English-learning infants. Cognitive Psychology, 39, 159-207.
Peters, B., Kohler, K., & Wesener, T. (2005). Melodische Satzakzentmuster in prosodischen
Phrasen deutscher Spontansprache - Statistische Verteilung und sprachliche Funktion.
In K. Kohler, F. Kleber & B. Peters (Eds.), Prosodic Structures in German
Spontaneous Speech (AIPUK 35a) (pp. 185-201). Kiel: IPDS.
Truckenbrodt, H. (2007). Upstep on edge tones and on nuclear accents. In C. Gussenhoven &
T. Riad (Eds.), Tones and tunes. Volume 2: Experimental studies in word and sentence
prosody (pp. 349-386). Berlin: Mouton de Gruyter.