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The prevalence of lisping in young adults
Journal of Communication Disorders 40 (2007) 493–502
The prevalence of lisping in young adults John Van Borsel a,*, Sigrid Van Rentergem b, Leen Verhaeghe b a
Ghent University Hospital, Faculty of Medicine and Health Sciences, Belgium b Ghent University, Faculty of Arts and Philosophy, Belgium
Received 19 May 2006; received in revised form 21 September 2006; accepted 11 December 2006
Abstract This paper reports the results of a pilot study that investigated the prevalence of lisping in a cohort of young adults. The motivation for the study was the observation that a substantial number of incoming students in speech language pathology at the Ghent University (Belgium), still presented with frontal lisping of the /s/, /z/ and sometimes other alveolar sounds too. Seven hundred and forty eight students (374 females, 374 males), native speakers of Dutch, were video-recorded while reading aloud the Dutch version of the text ‘‘The north wind and the sun. . .’’ from the International Phonetic Association (1974). Analysis of the samples yielded an overall prevalence of lisping of 23.3%. Significantly less participants presented with lisping among students of humanities than among students of natural sciences or social sciences. No significant difference was found between males and females. It remains to be determined if this high prevalence of lisping in adults represents a recent trend or if the persistence of the pattern of lisping into adulthood in some individuals is perhaps quite normal. Learning outcomes: As a result of this activity, the participant will be able to (1) discuss the nature and prevalence of residual phonological errors in general and (2) to discuss the prevalence of lisping in young adult native speakers of Dutch in particular. # 2007 Elsevier Inc. All rights reserved.
1. Introduction Speech sound acquisition is a relatively lengthy process that takes several years. It is normally only at about the age of seven or eight that children are capable of producing most sounds of the mother tongue (Wellman, Case, Mengert, & Bradbury, 1931; Poole, 1934; * Corresponding author at: UZ Gent 2P1, De Pintelaan 185, 9000 Gent, Belgium. Tel.: +32 9 240 22 96; fax: +32 9 240 49 93. E-mail address: [email protected] (J. Van Borsel). 0021-9924/$ – see front matter # 2007 Elsevier Inc. All rights reserved. doi:10.1016/j.jcomdis.2006.12.001
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Templin, 1957; Kilminster & Laird, 1978; Smit, Hand, Freilinger, Bernthal, & Bird, 1990; Ruscello, 2003; for Dutch in particular Stes & Elen, 1991; Van Borsel, 1995). Some sounds are mastered early. Others, however, are intrinsically more difficult and continue to be misarticulated for several years. Among the sounds that have been found to be acquired only later are the fricatives and affricates, especially the /s/ (Stoel-Gammon & Dunn, 1985; Winitz, 1969; for Dutch in particular Stes & Elen, 1991). While the acquisition of speech sounds has been studied extensively in preschool- and early school-age children since the late 1930s (Pena-Brooks & Hegde, 2000), less is known about the persistence of certain patterns of misarticulation into later life. According to Leske (1981) approximately 4% of 11 year olds and 1% of 17 year olds continue to have a speech sound disorder. Gillespie and Cooper (1973) and Culton (1986) reported a prevalence of speech sound disorders in junior and senior high-school students and among college freshmen, respectively, of 2.1% and 1.37%. In addition, follow-up studies by King, Jones, and Lasky (1982) and Felsenfeld, Broen, and McGue (1992) show that children earlier diagnosed as speech disordered may continue to show problems well into adulthood. Some studies in adolescent and adult residents of penal institutions too reported that speech sound disorders were the most frequent type of communication disorder observed (Belenchia & Crowe, 1983; Wagner, Gray, & Potter, 1983; Bountress & Richards, 1979). Speech sound disorders that persist beyond the expected period of speech-sound development or normalization are considered a subtype of developmental disorders known as residual phonological errors (Shriberg, 1997; Shriberg & Kwiatkowski, 1982). Residual phonological errors most commonly include distortions of the sound classes of liquids, fricatives, and affricates. Although they are usually minor errors in terms of severity and do not interfere with intelligibility, normal speakers may react negatively to such speech variations (Ruscello, 2003). The motivation for the present study was an observation during the screening of incoming students in speech language pathology at the Ghent University (Belgium). It occurred to two colleagues of the first author that a substantial number of these students still presented with frontal lisping of the /s/, /z/ and sometimes other alveolar sounds too, i.e. the error pattern in which alveolar sounds are pronounced with the tongue either on or between the front teeth (Bleile, 2004). Before the age of six, lisping is not usually considered a speech sound disorder and it may even be regarded as ‘‘sweet, funny, or endearing’’ (http://members.tripod.com/ Caroline_Bowen/lisping.htm). In adulthood, on the other hand, the persistence of lisping may lead to frustration or embarrassment. There is also some evidence that adult speakers demonstrating lisping are evaluated more negatively than non-lisping peers. Mower, Wahl, and Doolan (1978) had adult listeners rate five adult male speakers, three of whom not lisping and two demonstrating frontal lisping, with regard to speaking ability, intelligence, education, masculinity, and friendship. The speakers demonstrating frontal lisping were rated lower than the nonlispers in all five categories investigated. Syrett and Brorson (2005) had 41 adults rating videos of two adult females while frontal lisping and while not frontal lisping. Participants rated the subjects in the lisping videos as more cooperative, kind, friendly, and nice than in the non-lisping videos. Similar results were reported earlier by Silverman (1976) with respect to lateral lisping.
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There are also lisping adults, however, who wish not to seek therapy and in some public figures a lisp has become a kind of trade mark and forms part of their image. It would seem then that lisping in adulthood is perhaps not a rare pattern and does not necessarily constitute a problem. To the best of our knowledge, there are no data available on the prevalence of lisping in adulthood. This paper reports the results of a study that investigated the prevalence of lisping in a cohort of young adults in Flanders, the northern part of Belgium.
2. Methodology 2.1. Participants The participants of this study were students, native speakers of Dutch, at the Ghent University. They were recruited by means of on-the street-sampling in student homes, student restaurants and faculty bars. All participants completed a questionnaire that asked for date of birth, sex, branch of study, the province they lived in, educational level of their parents, whether they considered themselves as having a speech sound disorder, and whether any one else had ever told them that they have a speech sound disorder (for the latter two questions the general term ‘‘speech sound disorder’’ (Dutch: ‘‘articulatiestoornis’’) was used, rather than the term ‘‘lisping’’ in order not to bias the results). Students in speech language pathology, who may have had special training in articulation, and individuals whose articulation may have been altered because they were wearing dental braces, were excluded. Participants were informed that they were going to contribute in a research project but they were not informed about the purpose of the investigation. Seven hundred and forty eight students (374 females, 374 males) were thus recruited. Age of the participants ranged between 18 and 22 years, with a somewhat higher proportion of subjects in the younger age groups: 18 years: N = 266; 19 years: N = 185, 20 years: N = 128; 21 years: N = 115; 22 years: N = 54. As far as field of study is concerned, there was an approximately even distribution between students of humanities (N = 261), natural sciences (N = 248) and social sciences (N = 239). There was also an approximately even distribution of females and males within each field of study (humanities: 134 versus 127; natural sciences: 122 versus 126; and social sciences: 118 versus 121, respectively). In addition, there was no significant difference (chi-square test, p = 0.334) in the proportion of students of each field of study within the different age groups. The majority of participants were living in the provinces East-Flanders (N = 441) and West-Flanders (N = 237), a minority was living in Antwerp (N = 59), Flemish Brabant (N = 33) or Limburg (N = 8). The question of the educational level of the parents revealed that the highest level of one or both parents was university in 302 individuals, polytechnic in 276 individuals, secondary school in 161 individuals, and elementary school in 9 individuals. 2.2. Procedure Participants were asked to read aloud the Dutch version of the text ‘‘The north wind and the sun. . .’’ from the International Phonetic Association (1974). In Dutch, this text consists
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of 200 words, containing 34 instances of /s/ or /z/ and 144 instances of other alveolar sounds (/t/, /d/, /n/, /l/).1 Digital video-recordings (close-up of the mouth) were made of each participant’s performance, using a Sony-camera DCR-TRV 60E and an external unidirectional microphone Philips SBC 3036. In order to reduce possible influence of background noise, the microphone was held relatively close, at approximately 15 cm, from the speaker’s mouth. Video-recording took place in as quiet as possible a room within a given location (mostly student homes, student rooms, and classrooms) and lasted about 40 s per participant. In no instance did a recording have to be discarded because of poor quality. 2.3. Data analysis and reliability For analysing the data, the recordings were replayed with the camera fed into a conventional television set (Philips model No. 14 PV 210/01). The analysis was performed by the three investigators of this study (JVB, a senior lecturer in logopaedics, trained in linguistics and neurolinguistics with ample clinical experience in speech disdorders, SVR and LV, gradutate students in linguistics with ample training in phonetics, speech sound acquisition, and pronunciation skills) and involved two steps. In the first step, the three investigators jointly watched and listened to the recordings and independently judged for each participant whether he or she presented with lisping. A participant was considered to be lisping when at least two of the three judges shared this opinion. In accordance with the observation that formed the motivation for the present study, only frontal lisping was considered. Lateral lisping, i.e. lisping with the airflow coming over the side of the tongue (Bleile, 2004) was not considered. In addition, no attempt was made to distinguish within frontal lisping between interdental and dentalized lisping. It could be argued that interdentality is more aberrant presenting a real speech disorder and addentality is only a very minor problem that should perhaps not be considered a disorder. Yet, as already outlined above even minor residual errors may entail negative reactions. Moreover, in Dutch, which has no dental or interdental sounds as part of the sound system, both are considered aberrant anyway. The procedure adopted classified 191 participants with lisping. The 191 participants selected in the first phase were subsequently judged a second time. In this phase consensus among the three judges was required for a participant to be diagnosed with lisping. This more stringent criterion was adopted in order not to inflate prevalence results. In addition, the recordings of 18 other participants were judged again too. They were participants who had not been diagnosed to be lisping in the first analysis, but who had explicitly mentioned lisping in response to the questions whether they considered themselves as having a speech sound disorder or whether any one else had ever told them that they have a speech sound disorder. Besides the determination of lisping prevalence overall, the data were further analysed for the independent variables sex, age, socio-economic status, and field of study. Statistical analyses (chi-square tests and where appropriate Fisher’s exact test) were performed using SPSS 11.0 (SPSS Inc., Heverlee, Belgium). 1
This number does not include the target sound /r/. In Dutch the phoneme /r/ has two allophones in free variation: an alveolar [r] and a uvular [R].
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3. Results 3.1. Overall During the second review of the subjects who had been identified as lisping, a total of 172 out of the original 191 subjects were unanimously identified by the judges. In addition, 2 of the 18 self-reported lispers were also identified. This yielded an overall prevalence of 23.3% (174/748) (95% Confidence Interval (CI) of 20.2% to 26.3). 3.2. Sex and age The prevalence of lisping was not significantly ( p = 0.299) higher or lower in females. (93/374, i.e. 24.9%; 95% CI of 20.5 to 29.3) than in males (81/374, i.e. 21.7%; 95% CI of 17.5 to 25.8). There was a significant difference ( p = 0.049) between the various age groups. As can be seen from the age breakdown in Table 1 lisping prevalence was highest in the 18 and 19 year old and lowest in the 22 year old. 3.3. Socio-economic status Fig. 1 shows the results split up for socio-economic status, as based on parental educational level. Lisping prevalence was higher in the elementary group (4/9, i.e. 44.4%; 95% CI of 12 to 76.9) than in the university (62/302, i.e. 20.5%), polytechnic (70/276, i.e. 25.4%), or secondary school group (38/161, i.e. 23.6%), (95% CI of 16–25.1, 20.2–30.5, and 16.9–30, respectively). Statistical analysis, however, did not reveal a significant difference ( p = 0.239) between the four groups. 3.4. Field of study Breakdown of the results according to field of study yielded a significant difference ( p = 0.008) between the three groups distinguished. Students of natural sciences showed the highest prevalence of lisping (69/248, i.e. 27.8%; 95% CI of 22.3 to 33.4), followed by students of social sciences (61/239, i.e. 25.5%; 95% CI of 20.0 to 31.1). The prevalence in students of humanities (44/261, i.e. 16.9%; 95% CI of 12.3 to 21.4) was significantly lower than in students of natural sciences ( p = 0.003) and students of social sciences ( p = 0.017). The difference between the natural sciences and the social sciences proved not significant Table 1 Prevalence of lisping Age
Prevalence
95% Confidence Interval
18 19 20 21 22
27.1% (72/266) 25.9% (48/185) 18% (23/128) 21.7% (25/115) 11.1% (6/54)
21.7–32.4 19.6–32.3 11.3–24.6 14.2–29.3 2.7–19.5
Breakdown by age.
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Fig. 1. Prevalence of lisping: Breakdown by socio-economic status based on parental educational level.
( p = 0.566). Further breakdown of the results of the humanities showed that lisping prevalence was still lower in students studying languages (8/65, i.e. 12.3%; 95% CI of 4.3 to 20.3) than in students of other disciplines (36/196, i.e. 18.4%; 95% CI of 13 to 23.8) but not significantly ( p = 0.258) (Fig. 2).
Fig. 2. Prevalence of lisping: Breakdown by field of study.
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3.5. Awareness Of the 174 individuals diagnosed with lisping, 152 (i.e. 87.4%) were not aware of having a speech sound disorder and never received any remarks from others either. Five individuals (2.9%) were aware of their lisping but it had never been pointed out to them by others, 7 participants (4.0%) were told that they were lisping but yet did not think they were lisping, and 10 individuals (5.8%) were aware of lisping and had been told so by others as well. Females appeared to be somewhat more often aware of their lisping than males (10/93, i.e. 10.8% versus 5/81, i.e. 6.2%) but not to a significant degree ( p = 0.283).
4. Discussion This study yielded three major results: the finding of a high prevalence of lisping in young adults overall, the finding of a significant difference in lisping prevalence according to field of study, and the finding of an equal number of male and female lispers. It is quite remarkable that almost one fourth of the individuals investigated presented with lisping. In reality the prevalence may even be still higher. Assessment in the present study was based on the subjects’ reading aloud. It is quite thinkable that this more formal mode of speaking entails a more careful articulation than spontaneous speech or conversation. Moreover, a quite stringent criterion was adopted so as to exclude any borderline or doubtful cases. The results are even more remarkable when compared to previous studies on residual phonological errors in general who reported prevalence figures between 1 and 4% (Leske, 1981; Gillespie & Cooper, 1973; Culton, 1986). On the other hand, these results do confirm the assumption by Ruscello (2003) that there are substantial numbers of individuals with residual phonological errors. The reason for the high prevalence of lisping recorded is not immediately clear and it is not clear either to what extent this pattern is a new phenomenon. One possibility is that the high prevalence of addental and interdental articulation is indeed of recent origin and that our finding reflects a changing attitude towards articulation in general and lisping in particular. One might hypothesize that nowadays there is a greater tolerance towards articulatory imprecision as part of a more casual lifestyle. In absence of any data on the prevalence of lisping in older generations for comparison, this hypothesis is of course hard to verify. At any rate this hypothesis would be in line with the finding that 87.4% of the individuals diagnosed with lisping never received any remarks on their speech. Another possibility, not incompatible with the foregoing, is that in some individuals lisping results from imitation of certain media figures or idols of the age group investigated. Again, such a hypothesis is difficult to prove. Still another possibility is that a more addental and interdental articulation is to be interpreted as a contact phenomenon between Dutch and English. As a result of the evolution of communication media and a trend toward globalization, young people nowadays hear much more English, than was the case some decennia ago. As English has dental sounds as part of its sound system, it is not impossible that some influence on the
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articulation of Dutch has taken place in some individuals. It should be recognized, though, that any studies that might support this hypothesis of addental and interdental articulation being a contact phenomenon are presently lacking. Breakdown of the results by age showed that lisping prevalence was highest in the younger age group and lowest in the older age group, possibly suggesting a decreasing trend with increasing age. Such a trend could mean that the greater tolerance towards articulatory imprecision is a recent phenomenon as suggested above. Alternatively, this finding could also mean that the pattern of lisping is a very persistent one that in some individuals is only overcome in young adulthood. The second major finding of the present investigation was that the prevalence of lisping differed significantly between students of different fields of study. Students of humanities showed a lower prevalence than students of natural sciences and social sciences. Within the humanities prevalence was still somewhat lower in students studying languages than other branches, though not significantly so. These results might simply indicate that linguistic competence along with articulatory skills is greater in some individuals than in others. Perhaps they also reflect that individuals differ with respect to the degree they value language, including a correct articulation. A third major result is that no significant difference in prevalence of lisping was found between girls and boys. This finding is noteworthy considering that most studies on articulatory development in children indicate that girls surpass boys (Winitz, 1969) and that generally speaking more male than female children tend to be identified as having a speech sound disorders (Bernthal & Bankson, 1981). Interestingly, Gillespie and Cooper (1973) who studied the prevalence of speech problems in junior and senior high schools reported more speech disorders in males than females but not for articulation. More females than males were assessed with speech sound disorders in each of the grades studied. It would seem that there is some shift in the sex ratio of the prevalence of speech sound disorders with age. This finding could mean that more boys than girls outgrow their initial speech sound problems. It might perhaps also reflect a greater tolerance toward certain speech patterns in females than in males. For reasons explained in the method section, no attempt was made in the present study to distinguish between dentalized and interdental frontal lisping. Though distinguishing between the two is not always straightforward, the difference being gradual rather than absolute, it might nonetheless be interesting to try to make this distinction in future studies. It is quite possible, for instance, that there are limits to a greater tolerance towards articulatory imprecision and that only the persistence of addental lisping is gradually becoming normal but not marked interdental lisping. Finally, in the present study prevalence of lisping was investigated in a group of students taking into account sex, age, socio-economic status, and field of study as independent variables. One variable that was not considered but might well be worthwhile investigating is sexual preference. It is a popular stereotype that gay men lisp and it has even been suggested that lisping is used by gay people, either consciously or unconsciously, to express their sexual preference (http://www.joeclarck.org/soundinggay.html; http:// members.tripod.com/Caroline_Bowen/lisping.htm). In this respect, lisping might perhaps be considered typically female behaviour. However, these issues have, as far as we could ascertain, never been subjected to systematic investigation.
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In conclusion, this study revealed a high prevalence of lisping in young adults. It remains to be determined if this is a new trend or if the persistence of the pattern of lisping, or at least a certain degree, into adulthood in some individuals is perhaps quite normal. Data on the prevalence of lisping in both adolescents and older adults could help clarify this issue. We are not aware of any comparable data in other languages than Dutch. It would be interesting to see whether a similar prevalence of lisping shows up in languages which, unlike Dutch, have dental and interdental sounds as part of their sound system. Furthermore, the stereotypical belief that gay men lisp awaits empirical evidence.
Appendix A. Continuing education 1. Children are normally capable of producing most sounds of their mother tongue: a. at about the age of four. b. before the age of five. c. before the age of six. d. only at about the age of seven or eight. e. only at about the age of nine or ten. 2. Residual phonological errors most commonly include: a. distortions of the sound classes of liquids, fricatives, and affricates. b. omissions of the sound classes of liquids, fricatives, and affricates. c. substitutions of the sound classes of liquids, fricatives, and affricates. d. distortions of the sound classes of nasals and plosives. e. substitutions of the sound classes of nasals and plosives. 3. The overall prevalence of lisping found in the participants of this study was: a. 4.4%. b. 15.4%. c. 23.3%. d. 30.3%. e. 44.6%. 4. The prevalence of lisping in the participants of this study was: a. significantly higher in students of humanities than in students of natural sciences b. significantly higher in students of natural sciences than in students of social sciences c. significantly higher in females than in males d. significantly lower in females than in males e. not significantly higher or lower in females than in males 5. Of the individuals diagnosed with lisping: a. Females appeared to be significantly more often aware of their lisping than males. b. Males appeared to be significantly more often aware of their lisping than females. c. 87.4% were aware of their lisping but it had never been pointed out to them by others. d. 87.4% were not aware of having a speech sound disorder and never received any remarks from others either. e. 87.4% were told that they were lisping but yet did not think they were lisping. Answers: Q1 – d, Q2 – a, Q3 – c, Q4 – e, Q5 – d.
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References Belenchia, T. M., & Crowe, T. A. (1983). Prevalence of speech and hearing disorders in a state penitentiary population. Journal of Communication Disorders, 16, 279–285. Bernthal, J. E., & Bankson, N. W. (1981). Articulation disorders. Englewood Cliffs, NJ: Prentice Hall. Bleile, K. M. (2004). Manual of articulation and phonological disorders: Infancy through adulthood (2nd ed.). Clifton Park, NY: Thomson Delmar Learning. Bountress, N., & Richards, J. (1979). Speech, language and hearing disorders in an adult penal institution. Journal of Speech and Hearing Disorders, 44, 293–300. Culton, G. L. (1986). Speech disorders among college freshmen: A 13-year survey. Journal of Speech and Hearing Disorders, 51, 3–7. Felsenfeld, S., Broen, P. A., & McGue, M. (1992). A 28-year follow-up of adults with a history of moderate phonological disorder: Linguistic and personality results. Journal of Speech and Hearing Research, 35, 114–1125. Gillespie, S. K., & Cooper, E. B. (1973). Prevalence of speech problems in junior and senior high schools. Journal of Speech and Hearing Research, 16, 739–743. International Phonetic Association. (1974). The principles of the international phonetic association. London: International Phonetic Association. Kilminster, M. G. E., & Laird, E. M. (1978). Articulation development in children aged three to nine years. Australian Journal of Human Communication Disorders, 6, 23–30. King, R. R., Jones, C., & Lasky, E. (1982). In retrospect: A fifteen-year follow-up report of speech-language disordered children. Language, Speech, and Hearing Services in Schools, 13, 24–32. Leske, M. C. (1981). Prevalence estimates of communicative disorders in the US. ASHA, 23, 217–225. Mower, D. E., Wahl, P., & Doolan, S. J. (1978). Effect of lisping on audience evaluation of male speakers. Journal of Speech and Hearing Disorders, 43, 140–148. Pena-Brooks, A., & Hegde, M. N. (2000). Assessment and treatment of articulation and phonological disorders in children. Austin, TX: Pro-Ed. Poole, E. (1934). Genetic development of articulation of consonant sounds in speech. Elementary English Review, 11, 159–161. Ruscello, D. M. (2003). Residual phonological errors. In R. Kent (Ed.), Encyclopedia of communication disorders (pp. 156–158). Boston: MIT Press. Shriberg, L. D. (1997). Developmental phonological disorders: One or many? In B. W. Hodson & M. L. Edwards (Eds.), Perspectives in applied phonology (pp. 105–132). Gaithersburg, MD: Aspen Publishers Inc. Shriberg, L. D., & Kwiatkowski, J. (1982). Phonological disorders I: A diagnostic classification system. Journal of Speech and Hearing Disorders, 47, 226–241. Silverman, E. (1976). Listeners’ impression of speakers with lateral lisps. Journal of Speech and Hearing Disorders, 41, 547–552. Smit, A. B., Hand, L., Freilinger, J. J., Bernthal, J. E., & Bird, A. (1990). The Iowa articulation norms project and its Nebraska replication. Journal of Speech and Hearing Disorders, 55, 779–798. Stes, R., & Elen, R. (1991). Aspecten betreffende normatief onderzoek van de articulatie-ontwikkeling bij kinderen tussen 3 en 10 jaar. In L. Heylen & R. Elen (Eds.), Omtrent logopedie 8. Herentals: Vlaamse Vereniging voor Logopedisten. Stoel-Gammon, C., & Dunn, C. (1985). Normal and disordered phonology in children. Austin, TX: Pro-Ed. Syrett, S., & Brorson, K. (2005). The social implications of a frontal lisp. Poster presented at the ASHA Annual Convention. Templin, C. (1957). Certain language skills in children: Their development and interrelationships. Institute of Child Welfare, Monograph 26. Minneapolis: University of Minnesota Press. Van Borsel, J. (1995). Consonantinventarisatie bij adolescenten en volwassenen met het syndroom van Down. Stem-, Spraak- en Taalpathologie, 4, 25–37. Wagner, C. O., Gray, L. L., & Potter, R. E. (1983). Communicative disorders in a group of adult female offenders. Journal of Communication Disorders, 16, 277–296. Wellman, B., Case, I., Mengert, I., & Bradbury, D. (1931). Speech sounds of young children. University of Iowa Studies in Child Welfare 5(2). Winitz, H. (1969). Articulatory acquisition and behavior. Englewood Cliffs, NJ: Prentice-Hall.
The prevalence of lisping in young adults John Van Borsel a,*, Sigrid Van Rentergem b, Leen Verhaeghe b a
Ghent University Hospital, Faculty of Medicine and Health Sciences, Belgium b Ghent University, Faculty of Arts and Philosophy, Belgium
Received 19 May 2006; received in revised form 21 September 2006; accepted 11 December 2006
Abstract This paper reports the results of a pilot study that investigated the prevalence of lisping in a cohort of young adults. The motivation for the study was the observation that a substantial number of incoming students in speech language pathology at the Ghent University (Belgium), still presented with frontal lisping of the /s/, /z/ and sometimes other alveolar sounds too. Seven hundred and forty eight students (374 females, 374 males), native speakers of Dutch, were video-recorded while reading aloud the Dutch version of the text ‘‘The north wind and the sun. . .’’ from the International Phonetic Association (1974). Analysis of the samples yielded an overall prevalence of lisping of 23.3%. Significantly less participants presented with lisping among students of humanities than among students of natural sciences or social sciences. No significant difference was found between males and females. It remains to be determined if this high prevalence of lisping in adults represents a recent trend or if the persistence of the pattern of lisping into adulthood in some individuals is perhaps quite normal. Learning outcomes: As a result of this activity, the participant will be able to (1) discuss the nature and prevalence of residual phonological errors in general and (2) to discuss the prevalence of lisping in young adult native speakers of Dutch in particular. # 2007 Elsevier Inc. All rights reserved.
1. Introduction Speech sound acquisition is a relatively lengthy process that takes several years. It is normally only at about the age of seven or eight that children are capable of producing most sounds of the mother tongue (Wellman, Case, Mengert, & Bradbury, 1931; Poole, 1934; * Corresponding author at: UZ Gent 2P1, De Pintelaan 185, 9000 Gent, Belgium. Tel.: +32 9 240 22 96; fax: +32 9 240 49 93. E-mail address: [email protected] (J. Van Borsel). 0021-9924/$ – see front matter # 2007 Elsevier Inc. All rights reserved. doi:10.1016/j.jcomdis.2006.12.001
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Templin, 1957; Kilminster & Laird, 1978; Smit, Hand, Freilinger, Bernthal, & Bird, 1990; Ruscello, 2003; for Dutch in particular Stes & Elen, 1991; Van Borsel, 1995). Some sounds are mastered early. Others, however, are intrinsically more difficult and continue to be misarticulated for several years. Among the sounds that have been found to be acquired only later are the fricatives and affricates, especially the /s/ (Stoel-Gammon & Dunn, 1985; Winitz, 1969; for Dutch in particular Stes & Elen, 1991). While the acquisition of speech sounds has been studied extensively in preschool- and early school-age children since the late 1930s (Pena-Brooks & Hegde, 2000), less is known about the persistence of certain patterns of misarticulation into later life. According to Leske (1981) approximately 4% of 11 year olds and 1% of 17 year olds continue to have a speech sound disorder. Gillespie and Cooper (1973) and Culton (1986) reported a prevalence of speech sound disorders in junior and senior high-school students and among college freshmen, respectively, of 2.1% and 1.37%. In addition, follow-up studies by King, Jones, and Lasky (1982) and Felsenfeld, Broen, and McGue (1992) show that children earlier diagnosed as speech disordered may continue to show problems well into adulthood. Some studies in adolescent and adult residents of penal institutions too reported that speech sound disorders were the most frequent type of communication disorder observed (Belenchia & Crowe, 1983; Wagner, Gray, & Potter, 1983; Bountress & Richards, 1979). Speech sound disorders that persist beyond the expected period of speech-sound development or normalization are considered a subtype of developmental disorders known as residual phonological errors (Shriberg, 1997; Shriberg & Kwiatkowski, 1982). Residual phonological errors most commonly include distortions of the sound classes of liquids, fricatives, and affricates. Although they are usually minor errors in terms of severity and do not interfere with intelligibility, normal speakers may react negatively to such speech variations (Ruscello, 2003). The motivation for the present study was an observation during the screening of incoming students in speech language pathology at the Ghent University (Belgium). It occurred to two colleagues of the first author that a substantial number of these students still presented with frontal lisping of the /s/, /z/ and sometimes other alveolar sounds too, i.e. the error pattern in which alveolar sounds are pronounced with the tongue either on or between the front teeth (Bleile, 2004). Before the age of six, lisping is not usually considered a speech sound disorder and it may even be regarded as ‘‘sweet, funny, or endearing’’ (http://members.tripod.com/ Caroline_Bowen/lisping.htm). In adulthood, on the other hand, the persistence of lisping may lead to frustration or embarrassment. There is also some evidence that adult speakers demonstrating lisping are evaluated more negatively than non-lisping peers. Mower, Wahl, and Doolan (1978) had adult listeners rate five adult male speakers, three of whom not lisping and two demonstrating frontal lisping, with regard to speaking ability, intelligence, education, masculinity, and friendship. The speakers demonstrating frontal lisping were rated lower than the nonlispers in all five categories investigated. Syrett and Brorson (2005) had 41 adults rating videos of two adult females while frontal lisping and while not frontal lisping. Participants rated the subjects in the lisping videos as more cooperative, kind, friendly, and nice than in the non-lisping videos. Similar results were reported earlier by Silverman (1976) with respect to lateral lisping.
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There are also lisping adults, however, who wish not to seek therapy and in some public figures a lisp has become a kind of trade mark and forms part of their image. It would seem then that lisping in adulthood is perhaps not a rare pattern and does not necessarily constitute a problem. To the best of our knowledge, there are no data available on the prevalence of lisping in adulthood. This paper reports the results of a study that investigated the prevalence of lisping in a cohort of young adults in Flanders, the northern part of Belgium.
2. Methodology 2.1. Participants The participants of this study were students, native speakers of Dutch, at the Ghent University. They were recruited by means of on-the street-sampling in student homes, student restaurants and faculty bars. All participants completed a questionnaire that asked for date of birth, sex, branch of study, the province they lived in, educational level of their parents, whether they considered themselves as having a speech sound disorder, and whether any one else had ever told them that they have a speech sound disorder (for the latter two questions the general term ‘‘speech sound disorder’’ (Dutch: ‘‘articulatiestoornis’’) was used, rather than the term ‘‘lisping’’ in order not to bias the results). Students in speech language pathology, who may have had special training in articulation, and individuals whose articulation may have been altered because they were wearing dental braces, were excluded. Participants were informed that they were going to contribute in a research project but they were not informed about the purpose of the investigation. Seven hundred and forty eight students (374 females, 374 males) were thus recruited. Age of the participants ranged between 18 and 22 years, with a somewhat higher proportion of subjects in the younger age groups: 18 years: N = 266; 19 years: N = 185, 20 years: N = 128; 21 years: N = 115; 22 years: N = 54. As far as field of study is concerned, there was an approximately even distribution between students of humanities (N = 261), natural sciences (N = 248) and social sciences (N = 239). There was also an approximately even distribution of females and males within each field of study (humanities: 134 versus 127; natural sciences: 122 versus 126; and social sciences: 118 versus 121, respectively). In addition, there was no significant difference (chi-square test, p = 0.334) in the proportion of students of each field of study within the different age groups. The majority of participants were living in the provinces East-Flanders (N = 441) and West-Flanders (N = 237), a minority was living in Antwerp (N = 59), Flemish Brabant (N = 33) or Limburg (N = 8). The question of the educational level of the parents revealed that the highest level of one or both parents was university in 302 individuals, polytechnic in 276 individuals, secondary school in 161 individuals, and elementary school in 9 individuals. 2.2. Procedure Participants were asked to read aloud the Dutch version of the text ‘‘The north wind and the sun. . .’’ from the International Phonetic Association (1974). In Dutch, this text consists
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of 200 words, containing 34 instances of /s/ or /z/ and 144 instances of other alveolar sounds (/t/, /d/, /n/, /l/).1 Digital video-recordings (close-up of the mouth) were made of each participant’s performance, using a Sony-camera DCR-TRV 60E and an external unidirectional microphone Philips SBC 3036. In order to reduce possible influence of background noise, the microphone was held relatively close, at approximately 15 cm, from the speaker’s mouth. Video-recording took place in as quiet as possible a room within a given location (mostly student homes, student rooms, and classrooms) and lasted about 40 s per participant. In no instance did a recording have to be discarded because of poor quality. 2.3. Data analysis and reliability For analysing the data, the recordings were replayed with the camera fed into a conventional television set (Philips model No. 14 PV 210/01). The analysis was performed by the three investigators of this study (JVB, a senior lecturer in logopaedics, trained in linguistics and neurolinguistics with ample clinical experience in speech disdorders, SVR and LV, gradutate students in linguistics with ample training in phonetics, speech sound acquisition, and pronunciation skills) and involved two steps. In the first step, the three investigators jointly watched and listened to the recordings and independently judged for each participant whether he or she presented with lisping. A participant was considered to be lisping when at least two of the three judges shared this opinion. In accordance with the observation that formed the motivation for the present study, only frontal lisping was considered. Lateral lisping, i.e. lisping with the airflow coming over the side of the tongue (Bleile, 2004) was not considered. In addition, no attempt was made to distinguish within frontal lisping between interdental and dentalized lisping. It could be argued that interdentality is more aberrant presenting a real speech disorder and addentality is only a very minor problem that should perhaps not be considered a disorder. Yet, as already outlined above even minor residual errors may entail negative reactions. Moreover, in Dutch, which has no dental or interdental sounds as part of the sound system, both are considered aberrant anyway. The procedure adopted classified 191 participants with lisping. The 191 participants selected in the first phase were subsequently judged a second time. In this phase consensus among the three judges was required for a participant to be diagnosed with lisping. This more stringent criterion was adopted in order not to inflate prevalence results. In addition, the recordings of 18 other participants were judged again too. They were participants who had not been diagnosed to be lisping in the first analysis, but who had explicitly mentioned lisping in response to the questions whether they considered themselves as having a speech sound disorder or whether any one else had ever told them that they have a speech sound disorder. Besides the determination of lisping prevalence overall, the data were further analysed for the independent variables sex, age, socio-economic status, and field of study. Statistical analyses (chi-square tests and where appropriate Fisher’s exact test) were performed using SPSS 11.0 (SPSS Inc., Heverlee, Belgium). 1
This number does not include the target sound /r/. In Dutch the phoneme /r/ has two allophones in free variation: an alveolar [r] and a uvular [R].
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3. Results 3.1. Overall During the second review of the subjects who had been identified as lisping, a total of 172 out of the original 191 subjects were unanimously identified by the judges. In addition, 2 of the 18 self-reported lispers were also identified. This yielded an overall prevalence of 23.3% (174/748) (95% Confidence Interval (CI) of 20.2% to 26.3). 3.2. Sex and age The prevalence of lisping was not significantly ( p = 0.299) higher or lower in females. (93/374, i.e. 24.9%; 95% CI of 20.5 to 29.3) than in males (81/374, i.e. 21.7%; 95% CI of 17.5 to 25.8). There was a significant difference ( p = 0.049) between the various age groups. As can be seen from the age breakdown in Table 1 lisping prevalence was highest in the 18 and 19 year old and lowest in the 22 year old. 3.3. Socio-economic status Fig. 1 shows the results split up for socio-economic status, as based on parental educational level. Lisping prevalence was higher in the elementary group (4/9, i.e. 44.4%; 95% CI of 12 to 76.9) than in the university (62/302, i.e. 20.5%), polytechnic (70/276, i.e. 25.4%), or secondary school group (38/161, i.e. 23.6%), (95% CI of 16–25.1, 20.2–30.5, and 16.9–30, respectively). Statistical analysis, however, did not reveal a significant difference ( p = 0.239) between the four groups. 3.4. Field of study Breakdown of the results according to field of study yielded a significant difference ( p = 0.008) between the three groups distinguished. Students of natural sciences showed the highest prevalence of lisping (69/248, i.e. 27.8%; 95% CI of 22.3 to 33.4), followed by students of social sciences (61/239, i.e. 25.5%; 95% CI of 20.0 to 31.1). The prevalence in students of humanities (44/261, i.e. 16.9%; 95% CI of 12.3 to 21.4) was significantly lower than in students of natural sciences ( p = 0.003) and students of social sciences ( p = 0.017). The difference between the natural sciences and the social sciences proved not significant Table 1 Prevalence of lisping Age
Prevalence
95% Confidence Interval
18 19 20 21 22
27.1% (72/266) 25.9% (48/185) 18% (23/128) 21.7% (25/115) 11.1% (6/54)
21.7–32.4 19.6–32.3 11.3–24.6 14.2–29.3 2.7–19.5
Breakdown by age.
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Fig. 1. Prevalence of lisping: Breakdown by socio-economic status based on parental educational level.
( p = 0.566). Further breakdown of the results of the humanities showed that lisping prevalence was still lower in students studying languages (8/65, i.e. 12.3%; 95% CI of 4.3 to 20.3) than in students of other disciplines (36/196, i.e. 18.4%; 95% CI of 13 to 23.8) but not significantly ( p = 0.258) (Fig. 2).
Fig. 2. Prevalence of lisping: Breakdown by field of study.
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3.5. Awareness Of the 174 individuals diagnosed with lisping, 152 (i.e. 87.4%) were not aware of having a speech sound disorder and never received any remarks from others either. Five individuals (2.9%) were aware of their lisping but it had never been pointed out to them by others, 7 participants (4.0%) were told that they were lisping but yet did not think they were lisping, and 10 individuals (5.8%) were aware of lisping and had been told so by others as well. Females appeared to be somewhat more often aware of their lisping than males (10/93, i.e. 10.8% versus 5/81, i.e. 6.2%) but not to a significant degree ( p = 0.283).
4. Discussion This study yielded three major results: the finding of a high prevalence of lisping in young adults overall, the finding of a significant difference in lisping prevalence according to field of study, and the finding of an equal number of male and female lispers. It is quite remarkable that almost one fourth of the individuals investigated presented with lisping. In reality the prevalence may even be still higher. Assessment in the present study was based on the subjects’ reading aloud. It is quite thinkable that this more formal mode of speaking entails a more careful articulation than spontaneous speech or conversation. Moreover, a quite stringent criterion was adopted so as to exclude any borderline or doubtful cases. The results are even more remarkable when compared to previous studies on residual phonological errors in general who reported prevalence figures between 1 and 4% (Leske, 1981; Gillespie & Cooper, 1973; Culton, 1986). On the other hand, these results do confirm the assumption by Ruscello (2003) that there are substantial numbers of individuals with residual phonological errors. The reason for the high prevalence of lisping recorded is not immediately clear and it is not clear either to what extent this pattern is a new phenomenon. One possibility is that the high prevalence of addental and interdental articulation is indeed of recent origin and that our finding reflects a changing attitude towards articulation in general and lisping in particular. One might hypothesize that nowadays there is a greater tolerance towards articulatory imprecision as part of a more casual lifestyle. In absence of any data on the prevalence of lisping in older generations for comparison, this hypothesis is of course hard to verify. At any rate this hypothesis would be in line with the finding that 87.4% of the individuals diagnosed with lisping never received any remarks on their speech. Another possibility, not incompatible with the foregoing, is that in some individuals lisping results from imitation of certain media figures or idols of the age group investigated. Again, such a hypothesis is difficult to prove. Still another possibility is that a more addental and interdental articulation is to be interpreted as a contact phenomenon between Dutch and English. As a result of the evolution of communication media and a trend toward globalization, young people nowadays hear much more English, than was the case some decennia ago. As English has dental sounds as part of its sound system, it is not impossible that some influence on the
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articulation of Dutch has taken place in some individuals. It should be recognized, though, that any studies that might support this hypothesis of addental and interdental articulation being a contact phenomenon are presently lacking. Breakdown of the results by age showed that lisping prevalence was highest in the younger age group and lowest in the older age group, possibly suggesting a decreasing trend with increasing age. Such a trend could mean that the greater tolerance towards articulatory imprecision is a recent phenomenon as suggested above. Alternatively, this finding could also mean that the pattern of lisping is a very persistent one that in some individuals is only overcome in young adulthood. The second major finding of the present investigation was that the prevalence of lisping differed significantly between students of different fields of study. Students of humanities showed a lower prevalence than students of natural sciences and social sciences. Within the humanities prevalence was still somewhat lower in students studying languages than other branches, though not significantly so. These results might simply indicate that linguistic competence along with articulatory skills is greater in some individuals than in others. Perhaps they also reflect that individuals differ with respect to the degree they value language, including a correct articulation. A third major result is that no significant difference in prevalence of lisping was found between girls and boys. This finding is noteworthy considering that most studies on articulatory development in children indicate that girls surpass boys (Winitz, 1969) and that generally speaking more male than female children tend to be identified as having a speech sound disorders (Bernthal & Bankson, 1981). Interestingly, Gillespie and Cooper (1973) who studied the prevalence of speech problems in junior and senior high schools reported more speech disorders in males than females but not for articulation. More females than males were assessed with speech sound disorders in each of the grades studied. It would seem that there is some shift in the sex ratio of the prevalence of speech sound disorders with age. This finding could mean that more boys than girls outgrow their initial speech sound problems. It might perhaps also reflect a greater tolerance toward certain speech patterns in females than in males. For reasons explained in the method section, no attempt was made in the present study to distinguish between dentalized and interdental frontal lisping. Though distinguishing between the two is not always straightforward, the difference being gradual rather than absolute, it might nonetheless be interesting to try to make this distinction in future studies. It is quite possible, for instance, that there are limits to a greater tolerance towards articulatory imprecision and that only the persistence of addental lisping is gradually becoming normal but not marked interdental lisping. Finally, in the present study prevalence of lisping was investigated in a group of students taking into account sex, age, socio-economic status, and field of study as independent variables. One variable that was not considered but might well be worthwhile investigating is sexual preference. It is a popular stereotype that gay men lisp and it has even been suggested that lisping is used by gay people, either consciously or unconsciously, to express their sexual preference (http://www.joeclarck.org/soundinggay.html; http:// members.tripod.com/Caroline_Bowen/lisping.htm). In this respect, lisping might perhaps be considered typically female behaviour. However, these issues have, as far as we could ascertain, never been subjected to systematic investigation.
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In conclusion, this study revealed a high prevalence of lisping in young adults. It remains to be determined if this is a new trend or if the persistence of the pattern of lisping, or at least a certain degree, into adulthood in some individuals is perhaps quite normal. Data on the prevalence of lisping in both adolescents and older adults could help clarify this issue. We are not aware of any comparable data in other languages than Dutch. It would be interesting to see whether a similar prevalence of lisping shows up in languages which, unlike Dutch, have dental and interdental sounds as part of their sound system. Furthermore, the stereotypical belief that gay men lisp awaits empirical evidence.
Appendix A. Continuing education 1. Children are normally capable of producing most sounds of their mother tongue: a. at about the age of four. b. before the age of five. c. before the age of six. d. only at about the age of seven or eight. e. only at about the age of nine or ten. 2. Residual phonological errors most commonly include: a. distortions of the sound classes of liquids, fricatives, and affricates. b. omissions of the sound classes of liquids, fricatives, and affricates. c. substitutions of the sound classes of liquids, fricatives, and affricates. d. distortions of the sound classes of nasals and plosives. e. substitutions of the sound classes of nasals and plosives. 3. The overall prevalence of lisping found in the participants of this study was: a. 4.4%. b. 15.4%. c. 23.3%. d. 30.3%. e. 44.6%. 4. The prevalence of lisping in the participants of this study was: a. significantly higher in students of humanities than in students of natural sciences b. significantly higher in students of natural sciences than in students of social sciences c. significantly higher in females than in males d. significantly lower in females than in males e. not significantly higher or lower in females than in males 5. Of the individuals diagnosed with lisping: a. Females appeared to be significantly more often aware of their lisping than males. b. Males appeared to be significantly more often aware of their lisping than females. c. 87.4% were aware of their lisping but it had never been pointed out to them by others. d. 87.4% were not aware of having a speech sound disorder and never received any remarks from others either. e. 87.4% were told that they were lisping but yet did not think they were lisping. Answers: Q1 – d, Q2 – a, Q3 – c, Q4 – e, Q5 – d.
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References Belenchia, T. M., & Crowe, T. A. (1983). Prevalence of speech and hearing disorders in a state penitentiary population. Journal of Communication Disorders, 16, 279–285. Bernthal, J. E., & Bankson, N. W. (1981). Articulation disorders. Englewood Cliffs, NJ: Prentice Hall. Bleile, K. M. (2004). Manual of articulation and phonological disorders: Infancy through adulthood (2nd ed.). Clifton Park, NY: Thomson Delmar Learning. Bountress, N., & Richards, J. (1979). Speech, language and hearing disorders in an adult penal institution. Journal of Speech and Hearing Disorders, 44, 293–300. Culton, G. L. (1986). Speech disorders among college freshmen: A 13-year survey. Journal of Speech and Hearing Disorders, 51, 3–7. Felsenfeld, S., Broen, P. A., & McGue, M. (1992). A 28-year follow-up of adults with a history of moderate phonological disorder: Linguistic and personality results. Journal of Speech and Hearing Research, 35, 114–1125. Gillespie, S. K., & Cooper, E. B. (1973). Prevalence of speech problems in junior and senior high schools. Journal of Speech and Hearing Research, 16, 739–743. International Phonetic Association. (1974). The principles of the international phonetic association. London: International Phonetic Association. Kilminster, M. G. E., & Laird, E. M. (1978). Articulation development in children aged three to nine years. Australian Journal of Human Communication Disorders, 6, 23–30. King, R. R., Jones, C., & Lasky, E. (1982). In retrospect: A fifteen-year follow-up report of speech-language disordered children. Language, Speech, and Hearing Services in Schools, 13, 24–32. Leske, M. C. (1981). Prevalence estimates of communicative disorders in the US. ASHA, 23, 217–225. Mower, D. E., Wahl, P., & Doolan, S. J. (1978). Effect of lisping on audience evaluation of male speakers. Journal of Speech and Hearing Disorders, 43, 140–148. Pena-Brooks, A., & Hegde, M. N. (2000). Assessment and treatment of articulation and phonological disorders in children. Austin, TX: Pro-Ed. Poole, E. (1934). Genetic development of articulation of consonant sounds in speech. Elementary English Review, 11, 159–161. Ruscello, D. M. (2003). Residual phonological errors. In R. Kent (Ed.), Encyclopedia of communication disorders (pp. 156–158). Boston: MIT Press. Shriberg, L. D. (1997). Developmental phonological disorders: One or many? In B. W. Hodson & M. L. Edwards (Eds.), Perspectives in applied phonology (pp. 105–132). Gaithersburg, MD: Aspen Publishers Inc. Shriberg, L. D., & Kwiatkowski, J. (1982). Phonological disorders I: A diagnostic classification system. Journal of Speech and Hearing Disorders, 47, 226–241. Silverman, E. (1976). Listeners’ impression of speakers with lateral lisps. Journal of Speech and Hearing Disorders, 41, 547–552. Smit, A. B., Hand, L., Freilinger, J. J., Bernthal, J. E., & Bird, A. (1990). The Iowa articulation norms project and its Nebraska replication. Journal of Speech and Hearing Disorders, 55, 779–798. Stes, R., & Elen, R. (1991). Aspecten betreffende normatief onderzoek van de articulatie-ontwikkeling bij kinderen tussen 3 en 10 jaar. In L. Heylen & R. Elen (Eds.), Omtrent logopedie 8. Herentals: Vlaamse Vereniging voor Logopedisten. Stoel-Gammon, C., & Dunn, C. (1985). Normal and disordered phonology in children. Austin, TX: Pro-Ed. Syrett, S., & Brorson, K. (2005). The social implications of a frontal lisp. Poster presented at the ASHA Annual Convention. Templin, C. (1957). Certain language skills in children: Their development and interrelationships. Institute of Child Welfare, Monograph 26. Minneapolis: University of Minnesota Press. Van Borsel, J. (1995). Consonantinventarisatie bij adolescenten en volwassenen met het syndroom van Down. Stem-, Spraak- en Taalpathologie, 4, 25–37. Wagner, C. O., Gray, L. L., & Potter, R. E. (1983). Communicative disorders in a group of adult female offenders. Journal of Communication Disorders, 16, 277–296. Wellman, B., Case, I., Mengert, I., & Bradbury, D. (1931). Speech sounds of young children. University of Iowa Studies in Child Welfare 5(2). Winitz, H. (1969). Articulatory acquisition and behavior. Englewood Cliffs, NJ: Prentice-Hall.