Is phonetic variation represented in memory for pitch accents ? Amelia E. Kimball Jennifer Cole Gary Dell Stefanie Shattuck-Hufnagel ETAP 3 May 28, 2015

H* discourse-new Important surprising Many, varying acoustic cues to pitch accent. What acoustic cues are listeners sensitive to? Pitch accent

Speakers imitate phonological features rather than phonetic details – Mixdorff, Cole, Shattuck-Hufnagel 2012 Listeners perceive question/statement pitch accent categorically. ( in Catalan as measured with behavioral tasks and MMN ERP.) – Borràs-Comes, Costa-Faidella, Prieto, and Escera Listeners don’t hear/remember prosodic information that is not meaningful in their language. – French, Hungarian, and Finnish speakers (Peperkamp and Dupoux 2002) – Polish speakers don’t reliably differentiate between lexical stress patterns (Dohmahs, Knaus,Orzechowska,Weise 2012) Previous evidence: Listeners are sensitive to phonological features, not phonetic form.

Yet… listeners use phonetic detail in online processing to categorize phonemes ERP “VOT effects present through a late stage of perceptual processing (N1 component) …independent of categories.” “acoustic information is encoded continuously, independent of phonological information.” Toscano, McMurray, Dennhardt, and Luck 2010 McMurray, Tanenhaus, Aslin 2002 Eyetracking

recognition memory affected by fine-grained similarity relations among voices. Goldinger 1996 These effects hold even for non- linguistic background noise such as a dog barking. Pufal and Samuel 2014 Yet… listeners encode acoustic detail in memory ”Seemingly irrelevant information, such as an unattended background sound, is retained in memory and can facilitate subsequent speech perception.”

Beavers love building H* OR Phonetic cues? Intensity, duration, F0 Phonological features? Pitch accents When listeners hear a word, what prosodic information do they encode in memory? two types of variation: 1.Sensitivity to variation in the acoustic realization of pitch accent. 2. Variation in listener’s perception of acoustic features.

Method Same/Different task Implemented online using Amazon Mechanical Turk and LMEDS (Mahrt 2013) 193 total subjects participated in six separate experiments. All subjects were self-reported native English speakers located in the United States. Their ages ranged from19-59 (mean=31,s.d. 8.4). Results reported here do not include subjects who did not finish the task (8) or self-reported bilinguals (5), leaving 30 subjects in each of the six experiments. Subjects

Two experimental tasks AX task Participants hear two words with one second of silence between. They click a button to indicate if these are the same recording or different recordings. Delayed AX task Participants hear four words (exposure), then a tone, then one of the four words again (test). Participants are asked to say whether the exposure version they heard was the same as the test. Listeners Hear: “beavers” “movies” “runners” “beetles” “BEEP” “movies” Listeners Hear: “beavers”

AccentDurationPitch AX Accent AXDuration AXPitch AX AX Delay Accent DelayDuration DelayPitch Delay

Accent Full sentences were recorded by a native English speaking linguist. Content words spliced from these sentences. 12 words, 96 trials “beavers” unaccented accented In a “different” trial, Listeners hear: “beavers”

Pitch “beavers” 25 Hz lowered 25 Hz raised pitch stylized to 10 Hz, manually moved up or down 25 Hz, creating a 50 Hz pitch difference resynthesized using PSOLA 12 words, 96 trials In a “different” trial, Listeners hear:

Duration 10% shortened 10% lengthened 20% duration difference. Pratt duration manipulation, 10 words, 80 trials In a “different” trial, Listeners hear: beavers

Subject chooses… SAMEDIFFERENT Files are… SAME hitmiss DIFFERENT false alarmcorrect rejection

Predictions for delayed AX Prediction

* * N.S. chance

Interim summary A small delay and interference before memory retrieval has a larger effect on subcategorical differences than on phonological differences. Listeners encode (some) phonetic detail, not just phonological features.

Individual variation

Listeners remember phonological features and phonetic cues, but across-category phonological differences are remembered better than within-category differences. Individuals vary in their memory for cues. Key results

Information about phonetic detail is encoded, but is not retrievable in the same way as phonological information. – Abstract phonological categories still a useful construct in explaining our data. – Subcategorical detail is present in memory (particularly for duration) Listeners vary in their memory for phonetic cues for pitch accent. – Cues may not be reliably perceived/remembered, even if they are reliably present. – Suggests that perceptual data is important to continued study of prosodic features. Implications

New Directions Predictors of individual differences What is the performance of English language learners? (ELLs with lexical tone L1?) Do these effects extend to whole sentences? What causes the forgetting?

Acknowledgements This study is supported by NSF BCS Tim Mahrt, Joe Roy Sarah Geoghan, Minqi Wang Slides, references, etc. available at ameliakimball.com