Download Telugu and Japanese

Telugu and Japanese: a case for the use of rhythmic similarities in speech segmentation
Dr. Lalita Murty
University of York
Segmentation Processes
—  Speech is continuous and the only way to understand an u;erance is to understand the words of which it is made up.
—  There is nothing in the speech signal to mark the boundaries of words. —  T h e r e f o r e , a p r e r e q u i s i t e f o r u n d e r s t a n d i n g w o r d s i s t h e segmentation of individual words that make up the speech signal.
—  Words, however, cannot be recognised in a linear fashion one by one, primarily because words overwhelmingly contain other words. E,g. star may turn out to be startle, start, starch, stark? Rhythm in Listening
Listeners process spoken language in ways that are subtly suited to the phonological structure of their native languages.
One aspect of language structure which affects listening processes is Rhythm.
Linguists have identified 3 types of rhythmic pa;erns in languages: —  Stressed timed languages like English and Dutch
—  Syllable timed languages such as Spanish and French.
—  Mora based languages like Japanese and some languages spoken in South India.
Pycholinguistic research has shown that similar rhythmic structure encourage similar types of processing in listening.
Languages that differ in rhythmic structure encourage different types of processing
—  French listeners and not English, use the syllable as a segmentation cue (Cutler, Mehler, Norris and Segui, 1983, 1986)
—  English listeners have a stress-­‐‑based segmentation strategy (Bu;erfield and Cutler, 1988; Cutler and Norris, 1988; Cutler, Mehler, Norris, and Segui, 1989, 1992).
—  French and English have been held as the examples supporting the rhythmic distinction between syllable-­‐‑timed and stress-­‐‑times languages.
Speech segmentation in Japanese
— 
— 
Japanese-­‐‑speakers detect word-­‐‑
initial targets such as ta-­‐‑, tan-­‐‑ if the target is exactly one mora (ta-­‐‑ in %
tanishi or tanshi) missed
or two (tan-­‐‑ in tanshi)
They fail to detect targets not aligned with mora boundaries (tan-­‐‑ in tanishi)
tanishi
tanshi
70
60
50
40
30
20
10
0
ta-
(Otake, Hatano, Cutler & Mehler, 1993)
tan-
Segmentation of non-­‐‑native speech
Predictions: —  1. Listening to a non-­‐‑native language with the same rhythmic structure should be easier than listening to a non-­‐‑native language with a differing rhythmic structure.
— 
2. “Native”-­‐‑like segmentation of a given language by non-­‐‑native listeners should only be possible for listeners whose native language encourages the same segmentation procedure. Listeners with other languages will apply their different procedures, inefficiently.
The present study
Aim: The study investigates the possibility of rhythmic similarity classes comprising of sets of potentially unrelated languages, Japanese and Telugu both of which are considered to be MORAIC languages (Caldwell, 1856; Shiba, 1972; Ohno, 1981).
The prediction is that in a fragment monitoring task, listeners of both languages will use the mora as a cue for segmentation in their respective languages as well as each others’ languages.
What is a mora?
A mora is a subsyllabic unit. Vowels may be short (giving the syllable structures V, CV. CCV) or long (VV, CVV, CCVV);
a consonantal coda can only be a Nasal (VN, CVN, CCVN) or a geminate with the onset of the following syllable (thus only Nasals can be word final codas). Syllables with a short vowel consist of one mora, syllables with a long vowel or a nasal coda consist of two moras (bimoraic). Japanese and Telugu material
Material: 16 meaningful Japanese and Telugu words in eight pairs were respectively presented : Japanese: tanshi-­‐‑tanishi; monaka-­‐‑ monka; kinori-­‐‑
kinri.
Telugu: penku-­‐‑penamu; winta-­‐‑winati; manawi-­‐‑
manta; chembu-­‐‑chemata
(Murty, Cutler and Otake: 2007)
These 16 pairs were embedded in 250 other words arranged in 64 sequences. Each target word appeared twice: once in the one of the first 32 sequences and once in the of the last 32 sequences. The sequence length varied form 3-­‐‑6 words.
Fragment or phoneme monitoring task
Subjects were asked to listen for a specified fragment which would occur at the beginning of one word in a list of words . E,g they listened for ‘che’ in a list of 5-­‐‑7 words which includes the word ‘chemata’ and pressed a bu;on as soon as they heard it
Subject listened to 2 types of words and pressed a bu;on when they heard either one of two types of fragments:
Word type: CVNCV; CVCVCV
Target Types: CV; CVN
E.g.:
ta (CV) in tanshi (CVNCV) or in tanishi (CVCVCV)
Tan (CVN) in tanshi (CVNCV) or in tanishi (CVCVCV) Prediction
—  Subjects will find it easy to identify ta in tanshi (CVNCV) or tanishi (CVCVCV) because it is equal to one mora and syllable
—  Subjects will find it easy to identify tan in tanshi because it is equal to one syllable (tan-­‐‑) and 2 moras – ta-­‐‑ and n —  Subjects will have problems identifying tan in tanishi because it is more than one syllable and less than a mora.
Japanese and Telugu rhythm
• 
• 
40
Telugu has mora-­‐‑based rhythm, like Japanese
Telugu listeners show a Japanese-­‐‑like pa;ern with input in Japanese; Japanese listeners show the same pa;ern with input in Telugu.
% Miss Rates Telugu-Japanese
Japanese-Telugu
40
30
30
tanishi
tanshi
20
manishi
mandu
20
10
10
ta-
ma-
tan-
(Murty, Otake & Cutler, 2007)
man-
Overall findings of the study
Japanese Materials
—  Japanese-­‐‑speakers detect word-­‐‑initial targets such as ta-­‐‑, tan-­‐‑ if the target is exactly one mora in both Japanese and in Telugu (ta-­‐‑ in tanishi or tanshi; ma-­‐‑ in manishi or mandu ) or two (tan-­‐‑ in tanshi; man-­‐‑ in mandu)
—  They fail to detect targets not aligned with mora boundaries (tan-­‐‑ in tanishi; man-­‐‑ in manishi) —  Telugu listeners ‘ performance on Japanese words was very similar to that of native Japanese speakers, the miss rate for CVN target in CVNCV words was double that in the other three conditions. And the responses to those targets are slower than in any other three conditions.
Telugu Materials
—  Telugu speakers performance on Telugu words was mixed as there were no significant results, but the general advantage for CV targets in both CVCVCV and CVNCV words was similar to that of Japanese speakers. Japanese listeners responded to Telugu material in the same way as they did to in words their own language.
—  Telugu speakers clearly used strategies similar to those of Japanese speakers when listening to Japanese words, thus showing a tendency to use mora-­‐‑based listening strategies, even if they did not appear to be as strongly dependent as their Japanese counterparts on such strategies when listening to words in their native language.
—  Nevertheless, the results on the whole lend support to the rhythmic segmentation hypothesis.
—