Changes in shape, space and time: the impact of position on the spatiotemporal and configurational articulatory properties of liquid consonants.

Lead Research Organisation: Queen Margaret University Edinburgh
Department Name: Speech and Hearing Sciences

Abstract

The speech sounds 'L' and 'R' are often grouped together as a class (called 'liquid consonants'), because they are similar in a number of ways. For example, although they function as consonants in speech, they have a vowel-like phonetic quality. The are also among the most complex speech sounds to produce (and may be late acquired by children or hard for adult learners to master). They vary widely in different accents of the same language. Finally, their production can involve the tongue forming multiple constrictions in the vocal tract and they sometimes involve specific movements of the lips as well.

Although speakers are not always aware of it, the 'L' sounds at the beginning and end of a word like 'level' do not sound exactly the same. Likewise the R' sounds at the beginning and end of a word like 'roar' (for those so-called 'rhotic' speakers who pronounce an 'R' at the end of 'roar' at all!) do not sound exactly the same. Behind the difference in sound quality is complex variation in (i) the way the articulatory organs synchronise their movements (ii) the strength of the production of the speech sound and (iii) the shape of the tongue when the speech sound is produced. When an 'L' or 'R' at the beginning of a word is pronounced, the speech organ movements involved tend to be more tightly synchronised than for an 'L' or 'R' at the end of a word. Also, 'L' and 'r' at the beginning of words are produced with more effort than they are at the ends of words. Finally, the tongue shapes involved in the production of 'L' and 'R' at the beginning and ends of words can be radically different from one another. These remarkable differences are very hard to measure, but research over many decades has addressed and raised a number of theoretical questions.

Variation in these three parameters can cause very noticeable changes in the way 'L' and 'R' sound, explaining why, at the end of words, they seem less like consonants and more like vowels, e.g. making 'foal' and 'foe' sound very similar. The consonant might even disappear altogether, as occurred 200 years ago to 'R' at the end of the words in the RP accent of English. Thus, subtle variation in speech production can result in big changes in the long term. However, not all accents of English show the same patterns, or change at the same rate. While American and Irish English mostly have strong 'R' sounds at the end of words, word-final 'R' is starting to sound very weak and even be lost in some Scottish accents.

This project will use a vocal-tract imaging technique, ultrasound tongue imaging (UTI), to directly study the way the tongue moves inside the mouth when it is producing 'L' and 'R', informing theories of speech articulation. The movement of the lips will also be recorded, as they play an important part in the production of English 'L' and 'R' too. We will record differences in the timing of movements of different parts of the tongue and the lips, how extreme the movements are and how different the shape the tongue is when it is producing 'L' and 'R' in different positions within the word. We will also look at what happens to 'L' and 'R' across longer domains too, as it has been shown that the greatest changes in the way these sounds are produced are found when 'L' and 'R' occur at the beginning and end of speech utterances longer than single words. We will study how changes in the movements of the vocal organs correlate with changes in the acoustic speech signal and we will identify which kinds of variation in vocal organ movement are most likely to make 'L' and 'R' sound weak, vowel-like or missing.

Our research will focus on three key varieties of a single language in which 'R' is pronounced at the beginnings and ends of words, i.e. Scottish, Irish and American English. We will thus be able to address regional and historical variation within an otherwise well-understood language using novel methods to address theoretical questions relevant to all languages.

Planned Impact

Who will benefit from this research?

While this project will provide methods and findings which are fundamentally useful to academic researchers in phonetics and linguistics, the research will also be of practical use to non-academic users, speech and language therapists and their clients. The findings of this research is also likely to be useful to those working on text-to-speech synthesis. Economic benefit will come by keeping UK institutions ahead of the curve in terms of developments in speech imaging technology, developed in collaboration with Articulate Instruments Ltd. Finally, the public will benefit from this study through educational outreach.

How will they benefit?

Speech and Language Therapists (SLTs) and their clients will benefit from this research as the liquid consonants are often delayed or disordered in child speech. The articulatory complexity of liquid consonants perhaps explains the difficulty children have in acquiring these speech sounds. The fact that the sequencing of gestures varies depending on the position of the liquid segment in a syllable is a further complexity that children have to master. Nevertheless the kind of variation we see diachronically in liquids is often mirrored in disordered speech, e.g. coda liquids are produced as vocalized variants or are deleted. Our study can show SLTs the impact that different gesture sequencing can have on the auditory quality of liquids in order to help them identify what is happening in the vocal tract of their client and to help them develop remediation strategies. Our study can help to inform SLTs about the gestural complexity of liquids and the types of variation in tongue shape and tongue-gesture sequencing that we find across speakers and varieties of English. Our study will be able to provide clinical researchers with detailed information about the way that liquids are articulated in onset and coda position, across a variety of English accents, in a normative speech corpus.

Those who work with text-to-speech systems can benefit from out study. Speech synthesizers generally function most effectively when producing single sentences, but they are less successful at producing longer stretches of speech that sound natural. One challenge in synthezising longer speech stretches is to duplicate the prosody of natural speech. Phonetic variation found at utterance boundaries provides important prosodic perceptual cues for listeners. Our study will provide information on the types of acoustic variation that occur at prosodic boundaries, e.g. preboundary syllable lengthening, but also extreme changes in phonetic quality associated with prosodic boundaries.

The Speech and Hearing Sciences (QMU) impact return for REF2015 was rated at 3*(70%) or 4* (30%). The impact return included a case study on economic development via Articulate Instruments Ltd. Working in close partnership with Articulate Instruments has helped to keep both parties (AI and QMU's researchers) at the forefront of articulatory speech research and development. The current project pushes forward the technology by developing the first ever synchronised continuous ultrasound tongue imaging and lip video recording system. This system will prove invaluable to researchers around the world who wish to study articulation in spontaneous speech.

The public will benefit from this research through teaching outreach that will take place at "meet the scientist" events. We will be able to show, thought ultrasound demonstration, how the tongue moves inside the vocal tract. This has proved to be an engaging way to get people interested in speech research and ultrasound.

Publications

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Strycharczuk P (2017) Fronting of Southern British English high-back vowels in articulation and acoustics. in The Journal of the Acoustical Society of America

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Lawson E (2018) The role of gesture delay in coda /r/ weakening: An articulatory, auditory and acoustic study. in The Journal of the Acoustical Society of America

 
Description The effects of syllable and sentential position on tongue-gesture timing in /l/ and /r/ - Mixed effects modelling was used to analyse variation in the relative timing of the anterior (tongue tip or front) and posterior (tongue root) lingual gestures for /l/ and /r/ in syllable-onset and coda position and in utterance-initial, medial and final position. Results showed a consistent syllable-based pattern of gestural organisation for both /l/ and /r/ in all three accent varieties studied (American, Scottish and Irish English). At the beginning of the syllable, the tongue tip or tongue front gesture occurs before the tongue root gesture, while at the end of the syllable, this pattern is reversed. This finding confirms that of an earlier, smaller-scale study of American /l/ and suggests that there are universal patterns of gestural organisation. Additionally, it was found for /l/ that the greatest temporal distance between the anterior and posterior gestures occurred at sentence margins, but particularly in utterance-final position; however, this was not found to be the case for /r/.
Lawson, E. and Stuart-Smith, J. (accepted). "The effects of syllable and sentential position on the timing of lingual gestures in /l/ and /r/." In Proceedings of the 19th International Congress of Phonetic Sciences (ICPhS). 5-9th August, Melbourne, Australia.

The effects of syllable and sentential position on the gesture magnitude of /l/ and /r/ - Mixed effects modelling was used to analyse variation in normalised tongue-gesture magnitude (tongue tip or front height relative to the palate) for /r/ and /l/ in syllable-onset and coda position and in utterance-initial, medial and final position. Variation between onset and coda mean midsagittal tongue surfaces was also quantified as a distance value, whereby the mean distance between onset and coda variants of each consonant produced by each speaker was measured across the full length of the midsagittal tongue. Gesture magnitude of the anterior (tongue tip or tongue front) gesture was found to be significantly reduced in syllable-coda position for both /l/ and /r/ across the accent varieties studied (American, Scottish and Irish English). Again, gesture magnitude was significantly reduced in utterance-final position for /l/, but not for /r/, across the varieties of English studied. There was a greater difference (in terms of the mean distance measure described above) between onset and coda /l/ variants than between onset and coda /r/ variants. Palatal variants of /l/ (clear /l/) and /r/ (bunched /r/) consonants varied least between onset and coda position.
Lawson, E., Leplatre, G., Stuart-Smith, J., and Scobbie, J. M. (accepted). "The effects of syllable and utterance position on tongue shape and gestural magnitude in /l/ and /r/." In Proceedings of the 19th International Congress of Phonetic Sciences (ICPhS). 5-9th August, Melbourne, Australia.
Exploitation Route This study has shown consistent patterns of timing and gestural magnitude variation that are affected by both syllable position and utterance position in multiple varieties of English. These patterns help to explain allophonic variation in English and diachronic patterns of weakening and deletion of liquid consonants; however, it is still unclear whether this variation is language specific, or whether it is a universal feature of human speech articulation. A larger-scale study of multiple speakers, across multiple languages from different language families would help to answer this question.
Sectors Education,Healthcare

 
Description A new online resource, https://www.seeingspeech.ac.uk/r-and-l-in-english/, was created and added to Seeing Speech during this project (in 2018) and was officially launched in February 2019. The launch of this resource resulted in contact from a journalist from Washington-based Vox.com news site, who interviewed the project P.I. about production of /r/ and /l/ sounds; their complexity and difficulty and why they present difficulty for some east Asian English language learners.
First Year Of Impact 2018
Sector Education
Impact Types Cultural,Societal

 
Title Liquid consonants supplement to Seeing Speech www.seeingspeech.ac.uk 
Description A new ultrasound tongue imaging and lip camera video resource added to the Seeing Speech website. The resource comprises of a set of 16 new audio-articulatory videos, focussing on variants of the liquid consonants, /l/ and /r/ in British, Irish, American and West Indies English. 176 UTI and lip camera videos of productions of /r/, and 62 UTI and lip camera videos of productions of /l/, were exported in normal and quarter speed formats, processed and combined to produce composite videos of 10 articulatory categories of /r/ and 6 articulatory categories of /l/. This resource will help to shed more light on allophonic variation, sound change and speech production and will be of use to speech and language therapists in a clinical setting, i.e. providing models of real articulatory productions of two of the most complex and most frequently delayed/disordered phonemes. 
Type Of Material Database/Collection of data 
Year Produced 2018 
Provided To Others? Yes  
Impact Resource live on 9/11/2018 as part of a revamp of the Seeing Speech and Dynamic Dialects websites and officially launched on 8/02/2019. 
URL https://www.seeingspeech.ac.uk/r-and-l-in-english/
 
Description Being Human. Finding Glasgow, hidden secrets lost meanings, hidden tongues public engagement event 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Public/other audiences
Results and Impact A presentation to the general public demonstrating UTI, focussing particularly on /r/ sounds in English and Arabic. Attendees were from toddler to retirement age. Many attendees were refugees and asylum seekers.
Year(s) Of Engagement Activity 2017
URL https://beinghumanfestival.org/events/series/finding-glasgow-hidden-secrets-lost-meaning/
 
Description Conference paper and poster at Ultrafest 2017, Potsdam VIII, Germany, 4-6th October 2017 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other audiences
Results and Impact Conference presentation and poster on tongue gesture timing in rhotics and tongue and lip position for vowels. Outcomes were an invited talk to Institut für Phonetik und Sprachverarbeitung, LMU Munich to deliver talk on ultrasound method. Two requests for bite plates for probe to cranium stabilisation by Tom Starr-Marshall for a clinical project at University College London and Marienne Pouplier at Ludwig-Maximilians-Universität, Munich.
Year(s) Of Engagement Activity 2017
URL https://www.uni-potsdam.de/en/ultrafest8/program.html
 
Description East Lothian 10 year engagement activity 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Supporters
Results and Impact A QMU and East Lothian engagement event to promote research and impact in the local community and among local business leaders and third-sector workers. Current research project was one of two flagship areas invited to represent Queen Margaret University.
Year(s) Of Engagement Activity 2017
 
Description Edinburgh Science Festival (2017) 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Public/other audiences
Results and Impact place holder - est 100 per day. Verbal feedback on child speech development, phonetics, bi-dialectalism , sign-up for future research on the latter.
Glasgow / QMU
11-4, 10-14 April (25 hours engagement, > 50 hours researcher engagement)
twitter --> https://twitter.com/greentoes/status/851538641683984384
Year(s) Of Engagement Activity 2017
URL https://www.sciencefestival.co.uk/event-details/seeing-speech-hearing-tongues
 
Description Interview with Joss Fong for Vox.com on the pronunciation of /l/ and /r/ consonants 22/02/2019 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Media (as a channel to the public)
Results and Impact A journalist for Vox.com came across the /l/ and /r/ resource created as part of the Changes in Space, Shape and Time project and asked to conduct a Skype interview with PI Eleanor Lawson to find out more about the complexity of the articulation of these speech sounds and why some east Asians have difficulty learning them, (22/02/2019). The video article is currently under construction.
Year(s) Of Engagement Activity 2019
 
Description Invited talk at the Institut für Phonetik und Sprachverarbeitung, Munich. 7/2/2018 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact Eleanor Lawson was invited to give a talk entitled "Studying the performance of consonantal and vocalic variation using ultrasound tongue imaging and lip camera video." to staff, postgraduate students and researchers at the Institut für Phonetik und Sprachverarbeitung, Ludwig-Maximilians-Universität, Munich, Germany. The invitation was extended after a staff member at the Institut attended a conference talk given by Eleanor Lawson at Ultrafest 2017, Potsdam, Germany. The talk detailed articulatory methods used in the study of postvocalic rhotics and of vowels. In particular, the use of the bite plate to standardise probe to cranium angle and the development of measurement and normalisation techniques for ultrasound data. Marianne Pouplier also requested that Eleanor Lawson bring bite plates for use in the standardisation of probe to cranium angle at the Institut für Phonetik und Sprachverarbeitung.
Year(s) Of Engagement Activity 2018
URL http://www.phonetik.uni-muenchen.de/~pouplier/
 
Description Oral presentation at NWAV 2018 "An ultrasound-tongue-imaging study of rhoticity in a socially-stratified spontaneous speech corpus of Scottish English" 29th June 2018 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact An oral paper entitled "An ultrasound-tongue-imaging study of rhoticity in a socially-stratified spontaneous speech corpus of Scottish English" was delivered to attendees of a special session on Laboratory Phonology at the New Ways of Analysing Variation (NWAV) sociolinguistic conference in New York, June 2018. Originally a poster presentation was planned, but the organisers invited the author to present an oral paper. Founder of Variationist Sociolinguistics William Labov attended the session. After the presentation, we were contacted by a researcher at the University of Washington for practical help and advice in ultrasound recording. We sent them bite plates to help standardise ultrasound recording settings along with advice on undertaking ultrasound recordings. The researchers said "Than you so much for all the time,c are and effort you put into helping us prepare for our foray into ultrasound research. We value your experience and expertise greatly."
Year(s) Of Engagement Activity 2018
 
Description Poster presentation on the impact of phonotactic position and social class on coda /r/ tongue gesture timing in spontaneous speech at BAAP Colloquium 12th April 2018 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact A poster presentation on "The impact of phonotactic position and social class on coda /r/ tongue gesture timing in spontaneous speech". The talk showed that utterance final position is a key position for lingual gesture delay, across social classes. The poster described a mechanism whereby prosodic factors, such as utterance-final syllable lengthening, interact with mechanical speech movements, resulting in masking of speech sounds and audible weakening or deletion of utterance-final sounds in spontaneous speech.
Year(s) Of Engagement Activity 2018
URL https://blogs.kent.ac.uk/baap/files/2018/03/BAAP-2018_Lawson_etal2.pdf
 
Description Poster presented at the 4th Sound Change Workshop, April 11-17th, Edinburgh 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact The authors engaged with international academic researchers and students, explaining the project, preliminary findings and broader implications of those findings - discovery of a phonetic mechanism for coda liquid (and possibly other consonant) deletion. We have no specific impact to report, other than the interest of the researchers.
Year(s) Of Engagement Activity 2017
URL https://www.google.co.uk/search?hl=en&q=4th+sound+change+workshop&gws_rd=cr,ssl&dcr=0&ei=-lGdWvTCMoK...
 
Description Presentation at Michigan SLT/audiology workshop 
Form Of Engagement Activity Participation in an open day or visit at my research institution
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Undergraduate students
Results and Impact 23/ 07/2018 A presentation was made to Speech and Language Therapy students and Audiology students from the University of Michigan, USA, on the www.seeingspeech.ac.uk and www.dynamicdialects.ac.uk vocal-tract imaging resources. There was also an introduction to the new Liquids (/l/ and /r/) resource - not yet launched. The talk involved a tour of the websites, explaining the vocal-tract-imaging technologies involved, how the resources were created and how they can be used. There was a particular focus at the end of the talk on the new Liquid consonants resource, comparing production strategies for /r/ across varieties of English, including American English.
Year(s) Of Engagement Activity 2018
URL https://www.seeingspeech.ac.uk/redesign/
 
Description Public outreach Techfest 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact Public engagement talk on Seeing Speech and Dynamic Dialects and demonstration of ultrasound tongue imaging at Techfest, Science and Technology Festival in the North East of Scotland 9/09/2016.
Year(s) Of Engagement Activity 2016
URL http://www.aberdeenperformingarts.com/events/techfest-dynamic-dialects
 
Description Radio interview BBC Scotland - accent and social class 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact Eleanor Lawson was invited to take part in a discussion on "posh Scottish accents" on a Radio Scotland morning discussion programme, and was able to share findings of current and previous research, highlighting the resource www.dynamicdialects.ac.uk She explained changes that had occurred in middle-class and working-class Scottish speech over the past 60 years, with specific reference to the importance of /r/ in signalling social identity.
Year(s) Of Engagement Activity 2018
 
Description Radio interview on BBC Scotland regarding the impact of broadcast media and gaming on accent 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact Eleanor Lawson was invited to a radio interview on the Kay Adams show on Radio Scotland to discuss the impact of broadcast media and gaming on the accents of young people.
Year(s) Of Engagement Activity 2018
 
Description Scobbie Scotsman article on articulation of /r/ 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact An article in the Scotsman newspaper concerning research taking place at Speech and Hearing Sciences, Queen Margaret University Edinburgh, with a specific focus on the findings of articulatory research into /r/ and highlighting that the current project on changes in liquids is underway.
Year(s) Of Engagement Activity 2017
URL http://www.scotsman.com/news/opinion/jim-scobbie-i-am-addicted-to-the-noises-of-speech-1-4384202
 
Description Scottish Science Advisory Council - launch of SSAC science report and showcase for a science project from each HEI 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Policymakers/politicians
Results and Impact Prof Scobbie presented the results of the Ultraphonix project along with live ultrasound imaging as the QMU representative for the event. There was one representative project from each of the Scottish HEIs demonstrating excellence in science research and impact. Representatives from government were able to participate personally with the technology and reported support for and understanding of the basic science and an understanding of the need for enhanced technologies as a component in the treatment of speech disorders.
"An evening reception for MSPs and representatives from government, universities and research institutes, learned societies, business and industry and other key stakeholders." The organisers expected "approximately 150 guests working across the research base and in higher education, and in science, engineering, technology, social sciences, arts and humanities and business, to network and celebrate innovative research being carried out in Scotland. MSPs will also be in attendance. Mr Richard Lochhead MSP, Minister for Further Education, Higher Education & Science, will address the event before SSAC Chair Professor Paul Boyle highlights the key findings of the report, which was compiled by Elsevier for the SSAC."
Year(s) Of Engagement Activity 2019
 
Description Seeing Speech at International Agents Recruitment symposium, Glasgow University 4 March 2019 
Form Of Engagement Activity Participation in an open day or visit at my research institution
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other audiences
Results and Impact Seeing Speech, with a demonstration of the websites, and live ultrasound tongue imaging, was presented as a segment of a Glasgow University International Recruitment Agents Symposium. These are agents, largely from EU/overseas, who recruit students, especially postgraduate students for Masters courses, from their home country. The Seeing Speech segment was given twice, to half of the agents in turn, with an opportunity to discuss and demonstrate speech production in languages other than English, e.g. Arabic, Italic, Burmese. All participants were fascinated by the tongue imaging during speech, and were also very interested in the webresources, especially now that they are so easily accessible via mobile devices.
Year(s) Of Engagement Activity 2019
 
Description Uni of Konstanz Talk (Scobbie) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact Several dozen postgraduate students (masters and doctoral level) plus academic faculty attended an invited University Dept Seminar at the University Konstanz (14 Feb 2019) by Prog J.M. Scobbie titled "Fuzziness and indeterminacy around the phonetics / phonology interface".
Drawing on phonotactic and sociophonetic work on /r/ and on the clinical remediation of velar fronting, the talk presented a theoretical model of the phonetics-phonology interface. The audience discussed the topic, applying aspects of their model to categorical and gradient phenomena in their own work, including second language learning and prosody.
Year(s) Of Engagement Activity 2019
 
Description interview for 'accents' programme as part of BBC Radio 4's Broadcasting House; broadcast 18 November 2018 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact Personal invitation to contribute to a segment on 'accents, variation and change' for BBC Radio 4's Broadcasting House programme, which was broadcast on Sunday 18 November 2018. The programme producer, Dearbhail Starr, was fascinated by the material which I contributed, which covered phonetic variation and change in Scottish English, based on research relating to the articulatory phonetic investigation of speech, and large-scale analysis of speech variation across English accents.
Year(s) Of Engagement Activity 2018
URL https://www.bbc.co.uk/programmes/m00018sg
 
Description workshops for general public on 'Science Sunday' for Glasgow Science Festival 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact Hands-on workshops for the general public, presented as part of Glasgow Science Festival 'Science Sunday', 17 June 2018. Each workshop had 20+ participants, of all ages, from young children to grandparents, and this year, members of a local Russian language school. We demonstrated the websites, and carried out live ultrasound tongue imaging demonstration, with some other speech activities, and drawing activities for the children. Participants of all ages thoroughly enjoyed the workshop - none had ever had their speech imaged before, and were amazed to discover the role of the tongue in speech production.
Year(s) Of Engagement Activity 2018