american dialect society anaheim, ca jan. 2006 the impact of dialect on the rate and order of...
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American Dialect SocietyAnaheim, CA Jan. 2006
The Impact of Dialect on the Rate and Order
of Phonological Development
Shelley L. Velleman*, Barbara Zurer Pearson*, Timothy J. Bryant+ & Tiffany Charko@
*University of Massachusetts-Amherst+University of New Hampshire
@Agawam Public Schools
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Research supported by
NIH contract N01-DC-8-2104* and
NSF Award BCS-0318135
*webpage:www.umass.edu/aae
Contact for information: [email protected]
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With special thanks to
The Psychological CorporationThe Psychological Corporation,
who collected the data,
a host of dedicated graduate and
undergraduate students, and
our colleagues in the
UMass NIH Working Groups on AAE.
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AAE: African American EnglishAAE: African American English
• Also called African American Vernacular English (AAVE), Black English, Ebonics, etc.– Spoken by many Blacks in the U.S. – Pronunciation in some respects similar to Southern
American English– Pronunciation and grammar in some respects similar to
West African languages– Shares many characteristics with other Creole English
dialects spoken by Blacks• Stigmatized in the U.S.• Children who speak AAE are often referred for special
education or speech-language pathology services
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TerminologyWe are comparing MAE learners to “AAE
learners” BUTAAE learners are actually learning both
dialects; AAE is their 1st dialect, so we are making the
assumption that it will have the most impact on the order and rate of their phonological development
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Terminology, cont.
“Match”: child’s form matches adult MAE form
“Non-match”: child’s form does not match adult MAE match
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Terminology, cont.:
CONTRASTIVE CONTRASTIVE ELEMENTSELEMENTS
• Specific to AAE
• NOT characteristic of MAE
NONCONTRASTIVENONCONTRASTIVE ELEMENTSELEMENTS
• Common to AAE
and
MAE
Seymour & Seymour, 1977
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Same phonemic repertoire (with possible exception of voiced “th”) but
• Interdental fricatives replaced by labiodentals or alveolars, depending on context
• Postvocalic liquids: Vowelized, absent; /r/ hyperarticulated (varies geographically)
• Final obstruents more weakened (devoiced, glottalized), especially alveolars
• str-, “shr-” skr- (lexical?)
Key Segmental Features of AAE Predicted to be Contrastive
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Key Phonotactic Features of AAEPredicted to be Contrastive
Same structural repertoire but• Weak syllable deletion from iambics (or “stress
shift” to trochaic)• Final consonant clusters reduced at higher rate,
especially /___##C• Final obstruents and nasals omitted more
frequently, especially alveolars, especially /____##C
• Avoid sonority violations (lexical “metathesis”, very stigmatized)
Thus, phonotactic structures tend to be less complex
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Impact of Ambient LanguageImpact of Ambient Language
Previous cross-linguistic research has shown that frequency of occurrence impacts rate and order of phonological acquisition:– Kehoe & Lleo, 2002– Demuth, 2002– Roark & Demuth, 2000– Pearson et al., 1995– Boysson-Bardies & Vihman, 1991
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Research Question
What is the impact on rate and order of phonological development of learning two dialects that differ primarily with respect to frequency of occurrence, especially of complex phonotactic structures?
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Hypothesis 1
• Frequency will impact rate and order of acquisition even in two dialects with the same phonemic and phonotactic inventoriesNon-contrastive elements same exposure in
both equivalent mastery in bothContrastive elements less exposure in one
dialect later mastery in that dialect
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Hypothesis 2
• Phonotactic and segmental frequency will interactMost segments will be contrastive only
in marked environmentsFor AAE, only interdental fricatives will
be contrastive in all environments, marked and unmarked
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Hypothesis 3• In the dialect with less exposure to more
complex phonotactic structures (AAE), phonetic development will outpace phonotactic development (in comparison to MAE).
– AAE will have more phonotactic non-matches to MAE than segmental; MAE vice versa
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Study sample:
Children tested by The Psychological Corporation as part of the standardization process for the DELV.
Female Male Total
AAE 286 251 537
MAE 182 135 317
Total 468 386 854
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Other characteristics of the sample:• Selection criteria included demographics of
community of residence (predominantly African American vs. European American)
• Region: South (60%), North Central (25%), Northeast (6%), West (9%)
• Parent Education Level 77% ≤ HS
(overselected because AAE usage is higher in lower-income homes)
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Overall Match Score by Region and Dialect
92
96
100
104
108
112
AAE MAE
# of matches (of 132)
WE
SO
NC
NE
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Format• Sentence repetition• Target embedded in carrier phrase “I see: a mask; ..that fish breathe under water; ..a dentist”
66 words, each containing 2 segmental targets = 132 targets44 Contrastive: 88 Non-contrastiveCopyright 2000 The Psychological Corporation
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Targets
Singletons Clusters*
Initial 21 19
Medial 1 17
Final 19 15
Total 41 51
*Non-morphological cluster targets
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Singleton stimuli
Initial 21 types
31tokens
All (but /p/) Non Contrastive
Final 19 types
33 tokens
All Contrastive
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Cluster Stimuli Types,
Tokens
Non-Contrastive Contrastive
CC initial 16, 21 br-, dr-, kr-, fr-, pr-, tr-, gr-,sm-, st-, sk-, sp-, kr-, kl-, gl
r-, “shr-”
CCC initial 3, 4 skr-, spl- str-
CC medial 14, 16 -nd-, -nt-, -st-, -l-,
-ld- -fr-, -sk-, -kt-,
-ft-, -br-, -t-, -rp-
CCC medial 4, 4 -r$d-, -$br-,
-n$tr-, -$str-
($=syllable break)
CC final 15, 19 -st, -sk, -r, -rd, -rt,
-rl, -rs, -lt, -nt, -ks,
-mp, -ft, -ld, -lt, -rf
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Coding• Match to MAE target = 1• Nonmatch = 0
Phonetic (segmental) non-match:– Substitution– Distortion
Phonotactic non-match:– Omission (consonant or syllable)– Epenthesis (consonant or syllable)– Movement (consonant or syllable)
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Results for elements predicted to be contrastive
Contrastive Elements by Age and Dialect
42
44
46
48
50
52
54
56
58
4 5 6 8 10 12
Age in Years
Number of Matches
AAEMAE
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Results for elements predicted to be non-contrastive
Non-contrastive Elements by Age and Dialect
42
44
46
48
50
52
54
56
58
4 5 6 8 10 12
Age in Years
Number of Matches
AAE
MAE
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H1: Comparison of non-matches per child by position
AAE MAE
Initial(non-contrastive)
2.81 2.86
Final(contrastive)
3.82 1.76
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Non-contrastive Singleton Consonants by Age and Dialect
25
27
29
31
4 5 6 8 10 12
Age in Years
Matches (of 31 tokens)
AAE
MAE
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Phonetic order of acquisition: Initial consonants
Initial Consonants
MAE Age of Mastery
AAE Age of Mastery
d 4 5
r, s 6 4
Voiced “th” 8 ≥12
Dialects differ at p=.014 but p=.952 without voiced “th”.
All other initial consonants, including voiceless “th”, acquired at the same time in both dialect groups.
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Initial /r/ substitutions by age and dialect
p = .034 (chi-square)
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Production of Final Consonants
Score for Final Singleton Consonants by Age and Dialect
0.5
0.6
0.7
0.8
0.9
1
4 5 6 7-89-1011-12
Percent of matches
AAEMAE
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Phonetic order of acquisition: final C’s
Final Consonants
MAE age of mastery (90%)
AAE age of mastery (90%)
b, “j”, l 4 5
k, g, v 4 6
d, t 4 8
s, z 6 4
Voiced, voiceless “th”
10 ≥12
p <.0001 for age and dialect, even without voiced “th”.
Unexpected result: Non-morphological final /s, z/ mastered earlier by AAE learners
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Production of Initial Clusters (N.S.)
Initial Clusters MAE Age of Mastery
AAE Age of Mastery
tr- 4 5
kl-, pl 5 4
kr- 6 4
gr-, pr-, sp-, st-
6 5
skr- 8 6
“thr-” (vless) 8 10
“shr-” 8 12
str- 8 ≥12
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Initial Cluster Dialect Differences
Reminder: In AAE•str- skr e.g., [skrit] street•“shr-” skr- e.g., [skrImp] shrimp(Lexical?)
Note: Even in contrastive clusters such as these, /r/ itself is relatively preserved.
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Production of Final Clusters (p<.0001)Final Cluster MAE age of
masteryAAE age of mastery
-mp 4 4
-ks, -”ng”k, -rl 4 5
-rf, -nt 4 6, 8
-ld 4 10
-lt 4 >12
-rd 5 8
-rs 6 5
-rt 6 10
All others various ≤10 >12
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H2 Results: Some elements contrastive in marked positions only
Singleton /n/ by dialect and position
0.88
0.9
0.92
0.94
0.96
0.98
1
Initial Final
% MAE matches
AAE
MAE
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Elements contrastive in marked positions
Singleton /d/ by dialect and position
0.88
0.9
0.92
0.94
0.96
0.98
1
Initial Final
% MAE matches
AAE
MAE
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/d/: less frequent in final position in AAE(glottalized, devoiced, omitted)
• 4 years difference between AAE & MAE in final position• 1 year difference between AAE & MAE in initial position
• More vulnerable in other marked contexts, e.g., more frequent non-match in unstressed syllables even in initial position (dusty vs. destroy)
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InitialFinal
AAEMAE0.86
0.880.9
0.920.940.960.98
1
% match to MAE
Singleton /d/ by dialect and position
AAEMAE
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H2 Results: Some elements contrastive in all positions
Singleton /eth/ by dialect and position
0.4
0.5
0.6
0.7
0.8
0.9
1
Initial Medial Final
% MAE matches
AAE
MAE
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H3: Phonotactic vs. Segmental Non-Matches
Phonotactic Non-Match
Segmental Non-Match
AAE 2534 (49%) 2615 (51%)
MAE 514 (33%) 1046 (67%)
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But that includes final consonants and final clusters, both of which tend to be omitted -- no surprise.
What if we focus our analysis only on initial clusters, which are:
• Not significantly different in % mismatches by dialect
• Not yet mastered by either group?
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p<.0001
0
0.2
0.4
0.6
0.8
1
1.2
% of each type
AAE MAE AAE MAE AAE MAE
4 5 6
Mismatch Types by Age and Dialect(Initial Position)
subst
phon
Initial cluster mismatch types
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Summary1. Certain segments (e.g., voiced “th”) and
positions (e.g., ___#) are contrastive between dialects
2. A deficit model is inappropriate: Frequencies of occurrence in the dialect influence order of acquisition
• MAE speakers acquire certain phonemes (t, d, interdentals) ahead of AAE speakers
• AAE speakers acquire certain phonemes (s, r) ahead of MAE speakers
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Summary, cont.3. There are interactions between
phonotactic and segmental frequency effects (e.g., /d/)
4. Focus on learning complex phonotactics delays acquisition of more difficult segments (MAE); decreased attention to complex phonotactics lowers age of acquisition of later segments, even in more challenging contexts (AAE)
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References• Boysson-Bardies, B., & Vihman, M. M. (1991). Adaptation to language: Evidence from
babbling and first words in four languages. Language, 67, 297-319.• Charko, T. & Velleman, S. (2003, July). The influence of dialect of children’s phonotactic
constraint rankings (ND children). Poster presented at the Child Phonology Conference, UBC.
• Craig, H. K. & Washington,J. A. (2004). Grade-related changes in the production of African American English. JSHR, 47(2), 450-463.
• Kehoe, M., & Lleo, C. (2002). The acquisition of syllable types in monolingual and bilingual German and Spanish children. Paper presented at the Boston University Conference on Language Development 27, Boston, MA.
• Pearson, B. Z., Navarro, A. M., & Gathercole, V. M. (1995). Assessment of phonetic differentiation in bilingual learning infants, 18 to 30 months. In D. MacLaughlin & S. McEwen (Eds.), Proceedings of the 20th Annual Boston University Conference on Language Development (pp. 427-438). Somerville, MA: Cascadilla Press.
• Roark, B., & Demuth, K. (2000). Prosodic constraints and the learner's environment: A corpus study. In S. C. Howell, S. A. Fish & T. Keith-Lucas (Eds.), Proceedings of the 24th Annual Boston University Conference on Language Development (pp. 597-608). Somerville, MA: Cascadilla Press.
• Seymour, H.N. & Pearson, B. Z. (Eds.), 2004. Evaluating language variation: Distinguishing dialect and development from disorder. Seminars in Speech and Language, 25 (1),
• Seymour, H. N., Roeper, T., & de Villiers, J. (2003, 2005) Diagnostic Evaluation of Language Variation DELV, Screening Test and DELV-Norm Referenced. The Psychological Corp., San Antonio, TX.