Phonetics and phonology workshop archive
List of previous phonetics and phonology workshop speakers and topics
- 21st April 2016 (13:10-14:00), room 1.17, DSB: Patrycja Strycharczuk & Koen Sebregts (QMU & Utrecht University) 'Articulatory dynamics of degemination in Dutch'.
- 24th March 2016 (16:10-17:00), room 3.11, DSB (note unusual time - there's no Linguistic Circle on this day, so this is scheduled at that time): Jonah Katz (University of West Virginia) 'The function of lenition/fortition patterns: evidence from word segmentation.'
- 24th March 2016 (13:10-14:00), room 1.17, DSB: James Kirby 'Obstruent voicing, aspiration, and tone' and Bob Ladd & James Kirby ‘Obstruent effects on fundamental frequency: distinct aspects with distinct explanations’
- 11th March 2016 (note unusual day - this is a Friday) (13:00-14:00), room 1.17, DSB - a double-header: Martin Kohlberger (Leiden) 'Variation and sound change: nasal vowels in Shiwiar (Chicham, Ecuador)' and Joseph Brooks (UCSB) 'The phonologization of implosive prestopped nasals in Andamang Chini (Papuan)'.
- 2nd March 2016 (note unusual day - this is a Wednesday) (13:10-14:00), room 1.17, DSB: Report on Working with Personal and Sensitive Data. A joint event with the Language Variation and Change Research Group.
- 18th February 2016 (13:10-14:00), room 1.17, DSB: Bert Remijsen 'Phonological and morphophonological investigations on Shilluk - a progress report'.
- 14th January 2016 (13:10-14:00), room 1.17, DSB: Tina Bögel (Universität Konstanz) 'Pashto second position en(do)clisis and the syntax-prosody interface in LFG'.
- 3rd December 2015 - no meeting because of the Second Edinburgh Symposium on Historical Phonology (and note also the 'fringe' satellite meeting on 2nd December, on the History of Historical Phonology.)
- 18th November 2015 (note unusual day - this is a Wednesday)(14:10-15:00 - note unusual time), room 1.17, DSB: Joanna Kopaczyk, Benjamin Molineaux and Vasilis Karaiskos 'How to capture medieval sound-to-spelling correspondences? Database design and technical solutions for FITS'. A joint event with the English Language Research Group.
- 5th November 2015 (13:10-14:00), room 1.17, DSB: Ida Toivonen (Carleton University) 'The production and perception of intrinsic vowel duration'. [Vowels differ in their intrinsic duration. For example, the vowel in 'bat' is typically longer than the vowel in 'bit'. One relevant factor is vowel height: low vowels are longer than high vowels in English and cross-linguistically (e.g., Heffner 1937, House & Fairbanks 1953, Peterson & Lehiste 1960, Fischer-Jørgensen 1940, Abramson 1962). This talk revisits the correlation between vowel height and duration and tries to understand the reasons behind it. The traditional explanation for the positive correlation between height and duration appeals to physiology: low vowels take longer to produce because of the extra time it takes for the jaw to open (e.g., Lehiste 1970), or because the jaw position of high vowels is close to the jaw position held during the production of most consonants (Catford 1977). An alternative explanation is that each vowel has a phonologized duration target (e.g., Solé & Ohala 2010). If the duration of vowels depends directly on how much the jaw moves, we would expect a positive correlation within categories as well as between categories: multiple tokens of the same vowel would be expected to display a correlation similar to the correlation between vowels; i.e., a slightly lower pronunciation of a given vowel should be slightly longer. We investigate the vowel duration and height between and within categories in English and Swedish, using F1 as a measure of vowel height. The between-category investigation confirms previous studies: high vowels are shorter than low vowels. However, we did not find the same correlation within categories: a higher instance of the vowel in 'bit' is not shorter than a lower instance of 'bit'. If the positive correlation between height and duration cannot be directly explained by an appeal to physiology, we are left with the following question: Why is the generalization so robust cross-linguistically? In fact, it seems to be universal. We present a series of perception studies where participants were presented with minimal pairs differing in the height of the vowel (Stone 2015). The results indicate that speakers perceive low vowels as shorter than high vowels even when the vowels have been manipulated to have the same duration.]
- 29th October 2015 (13:10-14:00), room 1.17, DSB: George Starling. 'Perceptual learning of American English vowels from infant-directed speech' [Infants identify the phonetic categories present in the linguistic input that they receive within their first year of life. Current approaches to perceptual learning favour statistical learning as the mechanism behind this learning task. In this talk, I will review previous theoretical approaches to categorisation and discuss the current findings of my own acoustic analysis and statistical models. The vowel system of American English presents an ideal case study since it consists of a large set of phonetic categories that overlap in acoustic space. Previous statistical approaches to this task have failed to recover an appropriate category structure through bottom-up statistics alone. By analysing a large corpus of infant- and adult-directed speech, I aim to describe the acoustic properties of the vowels in caregivers' speech and assess the extent to which model learners can recover its underlying category structure.] A joint event with the Developmental Linguistics Research Group.
- 1st October 2015 (13:10-14:00), room B21 in 7 George Square: Joe Fruehwald 'Using Functional Data Analysis to study changes if vowel trajectories'.
- 3rd August 2015 (note unusual day - this is a Monday) (13:10-15:00), room 1.17, DSB: ICPhS 2015 practice presentations (Zac Boyd, Daniel Lawrence, James Kirby, Misnadin)
- 8th June 2015 note unusual day - this is a Monday (13:10-14:00), room 1.20, DSB: Adam Ussishkin (University of Arizona) 'Maltese root priming is morphological, not phonological'.
- 14th May 2015 (13:10-14:00), room 1.20, DSB: Laura Arnold 'Lexical tone in Ambel'. [Ambel is an Austronesian language spoken by around 1000 people on the island of Waigeo, in West Papua province, Indonesia. In this presentation I will use unpublished primary data to demonstrate that Ambel can be analysed as having tone. Lexical tone in Austronesian languages is very uncommon: of some 1200 Austronesian languages, Ambel is only the nineteenth to have been analysed as a tone language. I will use data from mono- and polysyllabic words in various contexts to show that there are two contrastive, non-predictable pitch patterns in Ambel - [H] and [LH]. I shall then use these phonetic data to explore possible analyses of the phonological system. Issues covered will include whether the domain of tonal specification is the syllable or the word, and whether the two-way surface contrast arises from a system which is underlyingly equipollent (/H/ vs /L/, or /H/ vs /LH/) or privative (/H/ vs /Ø/). Finally, I will locate the Ambel tonal system in a wider typological context.]
- 30th April 2015 (13:10-15:00), room 3.11, DSB: Post-Graduate Session: Merel Maslowski 'Differentiating between production-driven and perception-driven frequency effects in nonce homophones' and Udita Sawhney 'The tone system in Dogri, an Indo-Aryan language'.
- 2nd April 2015 (13:10-14:00), room 1.20, DSB: Joe Pater (UMass Amherst) 'Violable constraints in classical universalist phonology and beyond'. [Since the advent of OT in the mid nineties, the empirical scope and theoretical goals of the field of phonology have changed quite dramatically. In what we might call “Classical Universalist Phonology” (CUP) which started with the principles and parameters work of the early eighties, phonologists construct analyses of individual languages, and aim for theories of phonological grammar that generate all and only the possible systems that are inferred from this analytic work. OT as it was originally proposed is firmly in this tradition. CUP continues to be fruitfully practised in much of the current work in OT and its violable constraint relatives, Harmonic Grammar and Harmonic Serialism, as well as in other phonological frameworks. Increasingly, however, phonologists are working with data from corpora and experiments, which often provide information about the structure of phonological systems that cannot be obtained through traditional elicitation and judgment work. The explicit modeling of learning has also taken a much more central place in phonological theory, and typological generalizations are increasingly seen as emerging from the interaction of phonetics, learning and the properties of phonological grammar, rather than being derivable directly from the grammar itself. I’ll point out some ways in which violable constraints are useful in research that goes beyond CUP, which suggest to me that the shelf-life of OT, broadly construed, will be quite long for phonology, also broadly construed. I’ll also include some reminders of ways that violable constraints are useful in CUP.]
- 5th March 2015 (13:10-14:00), room 1.20, DSB: David Lorenz (Albert-Ludwigs-Universität Freiburg) and David Tizón-Couto (Universidade de Vigo) 'Speech rate and phonological environment as determinants of reduction: 'havda' and 'uzda' in spoken American English'. [Usage-based approaches to language generally assume that frequent sequences are 'chunked' and accessed non-compositionally (i.a. Bybee 2010, Langacker 2000). In spoken language, this may show in realizations that disregard the morphological components of a composite structure. We investigate this in the case of V-to-Vinf constructions in American English. Using data from the SBC (DuBois et al. 2000-2005), we examine the effects of speech rate and phonological environment on the realization of two types of the structure V to Vinf in American English: 'have to' and 'used to'. These items may undergo to-contraction (Aoun & Lightfoot 1984, Pullum 1997, Krug 2000), but the contractions are not conventionalized (unlike e.g. 'gonna'). Contraction, here defined as a reduction of the /t/-sound (flap or elision), is assumed to require non-compositionality. Speech rate is measured in syllables per second on the intonation unit; item frequencies are extracted from COCA (Davies 2008-). Across types, to-contraction is shown to be contingent on rapid speech; phonological context (specifically the following sound) affects only the final vowel (often realized as schwa). Moreover, contracted realizations of have to and used to are far less frequent than conventionalized contractions ('wanna', 'gonna'). These results suggest that 'havda' and 'uzda' are on-line reductions of non-compositional chunks, and that rapid speech potentially fosters the propagation of contracted variants.]
- 5th February 2015 (12:10-14:00 - note unusual time), room B21 in 7 George Square (note unusual place): Bert Remijsen 'Combining qualitative and quantitative approaches in the study of tone'. [This is a dry run for a masterclass at the 4th International Conference on Language Documentation & Conservation (University of Hawai'i at Manoa, February 26-March 1, 2015). Ear-based methods and quantitative analysis are both very useful in the study of tone. In order to combine them, one needs to understand how the auditory perception of pitch relates to the fundamental frequency pattern that gives rise to it. Crucial to this relation is the notion of tonal alignment. In this master class, I will explore this notion from phonetic and phonological angles, point out key findings in the experimental and typological literature, and illustrate the issues with many sound examples.]
- 22nd January 2015 (13:10-14:00), room 1.20, DSB: Benjamin Molineaux 'Prosodic structure and the fate of early English prefixes'. [English is unique among its nearest relatives in having lost most – but not all – of its native prefixes. This change took place in the transition between the language’s old and middle periods, and is traditionally chalked up to 'wholesale borrowing' from Norman French, 'which meant an enormous cut-down on the traditional patterns of word-formation' (Marchand, 1969:131). Closer inspection shows the causality and chronology of this argument to be untenable. Other accounts of the change come from semantics (Samuels 1972; Brinton 1989; Kastovsky 1992), syntax (Hiltunen 1983; Elenbaas 2007) and phonology (Lutz 1997), as well as from grammaticalisation-inspired theories (Hopper & Traugott 2003; Los et al. 2012). Thus far, however, such work has been restricted to explaining loss of either separable or inseparable verbal prefixes, while ignoring the simultaneous decay of nominal and adjectival ones. In this talk I will attempt a principled explanation of the conditions leading to early English prefix loss and preservation across word categories. I will use corpus data to assess the extent of the decline between the two periods, going on to propose syllable weight, foot structure, and the ability to constitute independent prosodic words as factors determining prefix preservation and loss. Finally, the growth of a constraint banning heavy monosyllabic prefixes in Early Middle English will be argued for. Constituting canonical feet and prosodic words, such prefixes would have borne a degree of stress, which clashed with adjacent root-initial stress. As a result, heavy monosyllabic prefixes (tō-, and-, up-, wið-) were either lost or lexicalized.]
- 28th August 2014 (13:10-14:00), room 1.17, DSB: Misnadin 'Temporal and spectral properties of the three-way laryngeal contrast of Madurese'.
- 9th October 2014 (13:10-14:00), room 1.17, DSB: Mits Ota in collaboration with Barbora Skarabela 'The phonology of baby-talk words'. [In most speech communities, there is a set of register-specific words used in addressing infants and young children (Ferguson, 1964, 1977, 1978). These typically take the form of lexical replacement such as 'choo-choo' (for train), and modification such as 'doggie' (for dog). It has long been recognized that these lexical items (?baby-talk words?) exhibit common form characteristics including the prevalence of reduplication, recurrent endings (e.g., -/i/ in English), lack of consonant clusters (cf. stomach vs. tummy), and favored prosodic structures (e.g., 'CVCV in English, CVG.GV in Arabic). However, little is understood about why baby-talk words exist at all or why they tend to have similar phonological patterns across languages. While traditional accounts focus on the resemblance between the observed common phonological structures and children's early vocalization or word production, recent findings in developmental research suggest another possibility; that is, the form characteristics in baby-talk words reflect perceptual or learning biases in infants' speech and language processing. For example, word forms containing adjacent repetition of syllables (e.g., mubaba) tend to attract the attention in young infants (Gervain et al., 2008; Gervain, Berent, & Werker, 2012) and word forms with uniform endings are easier to detect/learn (Kempe, Brooks, & Gillis, 2005; Kempe et al., 2007). In this talk, we present some preliminary outcomes of a series of experiments and analyses we have been conducting to test the hypothesis that phonological structures typical of baby-talk words facilitate word segmentation and word learning.]
- 23rd October 2014 (13:10-14:00), room 1.17, DSB: Alice Turk in collaboration with Stefanie Shattuck-Hufnagel (MIT) 'A sketch of an extrinsic timing model of speech production'.
- 27th November 2014 (13:10-14:00), room 1.17, DSB: Pavel Iosad 'Bottom-up phonologization of redundant features: vowel quality in south-west Welsh'. A joint event with the Celtic Linguistics Reading Group. [I present the results of a study of the phonologization of vowel quality in south-western dialects of Welsh as an example of bottom-up creation of phonological categories on the basis of predictable categorical distributions. Across Welsh dialects, the quality of (non-low) vowels in stressed syllables is closely intertwined with their length: generally, long stressed vowels are 'tense' while short stressed vowels are 'lax'. In contrastivist frameworks, the mutual predictability of length and quality forces analysts to choose one 'distinctive' feature. South-West Welsh varieties are described as deviating from this picture in allowing 'lax' long mid vowels before high vowels in a following syllable. This is a potential problem for a quantity-based contrastivist approach to Welsh vowels, such as the one in Iosad (2012). It is, however, conceivable that the pattern is not categorical but is instead a continuous trade-off in inherent vowel length. I present the results of a study of vowel quality in South Welsh. The study shows the existence of several types of quantity-quality interactions, including the one described for south-western dialects. I propose a bottom-up phonologization scenario based on learners picking up predictable distributions in the data. This analysis is supported by the patterning of exceptions and by the existence of a 'rule scattering' phenomenon.]
- 11th December 2014 (13:10-14:00), room 1.17, DSB: Amanda Cardoso and Patrick Honeybone 'Palatalisation can be quantity-sensitive: Dorsal Fricative Assimilation in Liverpool English'. A joint event with the English Language Research Group.
- 19th September 2013 (13:10-14:00), room 1.17, DSB: Martin Corley 'Analysing ultrasound articulation data in multiple-participant experiments'.
- 10th October 2013 (13:10-14:00), room 1.17, DSB: P-group business meeting.
- Wednesday 16th October 2013 (13:10-14:00), room 1.17, DSB: Nigel Fabb (Strathclyde) 'Prosodic phrasing and the delivery of poetry' [note the unusual day: Wednesday, not Thursday].
- 24th October 2013 (13:10-14:00), room 1.17, DSB: Andras Cser (PPKE, Hungary)'The split place node hypothesis: evidence from Latin'. [This talk discusses the hypothesis, going back to the early 1990’s and couched in different models in different ways since then, that in feature geometry the place features of consonants and the place features of vowels occupy different slots and/or are dominated by different higher-level nodes. Analyses of a number of phenomena from Latin are adduced in support of such a model, e.g. assimilations between consonants and vowels, the behaviour and diachronic development of gn-initial stems and the allomorphy displayed by the prefixcon-.]
- NB: Andras Cser will also be giving two special seminars open to students and staff - details below.
- 14th November 2013 (13:10-14:00), room 1.17, DSB: Rosey Billington (University of Melbourne) 'The sound system of Lopit'. [Ths talk will provide an overview of the sound system of Lopit, an un(der)described Eastern Nilotic language traditionally spoken in South Sudan. Following a description of the segmental and tonal phonology, I turn to the phonological and phonetic evidence for an 'advanced tongue root' type contrast among Lopit vowels, presenting experimental results of investigations into some of their acoustic and durational properties. Results show good evidence for such a contrast, but also indicate that a number of different cues are involved, and speakers may use these to different extents.]
- 5th December 2013 (13:10-14:00), room 1.17, DSB: Natalia Zharkova (QMU) 'Articulatory constraints in child speech: ultrasound tongue imaging and acoustic evidence'.
- 13th February 2014 (13:10-14:00), room 1.17, DSB: Bert Remijsen 'Evidence for contrastive tonal alignment in Shilluk'. [Many studies hypothesize or assume that tonal alignment is not contrastive in contour tones (e.g. Hyman 1988, Odden 1995, Silverman 1997, Yip 2002). However, in a recent study on Dinka, a Western Nilotic language of South Sudan, I have presented evidence of precisely this type of configuration for falling contours, i.e., of an Early-aligned Fall being in contrast with a Late-aligned Fall (Remijsen 2013). In Dinka, the Low and the Early-aligned Fall are contextually conditioned allophones of the same phonological category. On the hypothesis that tonal alignment is contrastive in contour tones, it should be equally possible for a human language to present a contrast of Low vs. Early-aligned Fall vs. Late-aligned Fall vs. High. The realisation of such a contrast would involve the same configuration of fundamental frequency, time-shifted relative to the syllable to produce four patterns. In this talk I will present evidence of this configuration in Shilluk, another Western Nilotic language.]
- 20th February 2014 (12:10-13:00), room 1.20, DSB: Martin Kraemer (Tromso) 'An amphichronic look at palatalization and gliding in Italian'. NOTE UNUSUAL TIME AND PLACE.
- 20th March 2014 (13:10-14:00), room 1.17, DSB: James Kirby 'Gestural coordination in Khmer word-initial clusters'.
- 17th April 2014 (13:10-14:30), room 1.17, DSB: Postgraduate session: Daniel Lawrence 'How much do listeners know about phonetic variation? Investigating socio-indexical knowledge through web-based experiments'; Misnadin 'Temporal and spectral characteristics of the three-way laryngeal contrast in Madurese'; and George Starling'Perceptual learning of vowel length categories in Japanese'.
- 1st May 2014 (13.10-14.00), room 1.17, DSB: Bob Ladd 'Quasi-contrastive phonetic categories'. Dry run of a talk to be presented at ISSP 10 (10th International Seminar of Speech Production) in Cologne the following week - feedback needed!
- 26th May 2014 (13.10-14.00): Rory Turnbull (Ohio State) 'Individual differences in phonetic reduction and audience design'.
- 18 Jul 2013 Speaker: Marton Soskuthy (University of Edinburgh) Topic: Phonetic biases and systemic effects in the actuation of sound change (pre-viva talk).
- 20 May 2013 Speaker: Sam Bowman (Stanford University) Topic: Two arguments for vowel harmony by trigger competition
- 02 May 2013 Postgraduate Student Presentations
- 22 Mar 2013 Speaker: Nikolaus Ritt (University of Vienna) Topic: The morphonotactics of word final consonant clusters in and after the Middle English period
- 14 Mar 2013 Speakers: Alice Turk & Stefanie Shattuck-Hufnagel Topic: What is speech rhythm? A Commentary.
- 27 Feb 2013 Speaker: Amanda Cardoso (University of Edinburgh) Topic: PRICE and MOUTH Variation in Scouse
- 07 Feb 2013 Speaker: Margaret (Peggy) Renwick (University of Oxford) Topic: Unpredicted Assimilations in UK English: Initial results from the Audio BNC
- 22 Nov 2012 Speaker: Amanda Cardoso (University of Edinburgh) Topic: Pre-velar raising in Western Canadian Dialects
- 08 Nov 2012 Speakers: Bert Remijsen (University of Edinburgh) Topic: About contrastive tonal alignment and how to represent it
- 16 Oct 2012 Speakers: Danielle Turton (University of Manchester) and Michael Ramsammy (University of Edinburgh) Topic: Unstressed vowel lowering in Mancunian English: a socio-phonological study
- 19 Apr 2012 Speaker: Tareq Maiteq (University of Edinburgh) Topic: Prosodic constituency structure and the spread of anticipatory pharyngealisation
- 12 Apr 2012 Speakers: Peter Racz (Universität Freiburg), Marton Soskuthy (University of Edinburgh) & Daniel Szeredi (New York University) Topic: A phonetic study of L-deletion in Hungarian
- 08 Mar 2012 Speaker: Péter Rácz (Universität Freiburg) Topic: Salience in sociophonetics - a case study of Hungarian hiatus resolution
- 23 Feb 2012 Speakers: Rebecca Schaefer, IMHSD (Reid School of Music, University of Edinburgh) Topic: Perception and imagination of melodies in EEG: a closer look at rhythmic processes
- 24 Nov 2011 Speaker: Alice Turk (University of Edinburgh) Topic: How is speech timing controlled? Part II: Articulatory Phonology & Task Dynamics
- 10 Nov 2011 Speaker: John Esling (University of Victoria) Topic: Infants acquire the speech sound production mechanism from day one - beginning in the pharynx
- 3 Nov 2011 Speaker: Alice Turk (University of Edinburgh) Topic: How is speech timing controlled? Part I: Articulatory Phonology & Task Dynamics
- 27 Oct 2011 Speaker: Stefan Frisch (University of South Florida, Fulbright-Cardiff University post-doctoral scholar) Topic: Influences on well-formedness judgments for novel nonwords
- 20 Oct 2011 Speaker: Andrew Wedel Topic: Words influence the evolution of sound category contrast: Evidence from simulation, corpus and laboratory studies
- 23 Jun 2011 Speaker: Bert Remijsen Topic: The effects of contrast maintenance and time pressure on the alignment of a rightward shifted high tone target in Dinka
- 16 Jun 2011 Speakers: Anthony Buhr and Robin Lickley Topic: Articulatory movement at cutoff: In search of hidden error
- 26 May 2011 Speaker: Natalia Zharkova (Queen Margaret University) Topic: Tongue dynamics and speech motor control in preadolescents
- 16 May 2011 Speaker: Stephanie Shih (Stanford University) Topic: On the nature of end weight in spoken English construction choice
- 07 Apr 2011 Speaker: Jennifer Nycz Topic: Changing dialects, changing representations? Testing phonological theory with second dialect data
- 11 Mar 2011 Speaker: John J. Ohala Topic: The connection between [ATR] and voicing in obstruents
- 9 Mar 2011 Speaker: John J. Ohala Topic: Ethological factors shaping human language
- 24 Feb 2011 Speaker: Tamara Rathcke Topic: On the neutralising status of truncation in intonation
- 17 Feb 2011 Speaker: José Hualde Topic: Intervocalic lenition
- 13 Jan 2011 Speaker: Akira Utsugi Topic: The perception of non-native lexical pitch accent by speakers of 'accentless' Japanese dialects
- 23rd October 2013 (14:10-16:00), room 3.10 then 3.11, DSB: Andras Cser (PPKE, Hungary) Issues in the phonological description of dead languages: case studies from Latin. [This talk discusses some preliminary methodological issues of the phonological and phonetic description of dead languages. Then case studies are presented from Latin that exemplify some interesting points either in terms of data or in terms of phonological interpretation. Depending on time, the case studies will include lateral dissimilation, variable assimilation at morpheme boundaries, contour segments vs. clusters and sequences (labiovelars, diphthongs), extrasyllabicity and resyllabification.]
- 25th October 2013 (15:10-17:00), room 1.17, DSB: Andras Cser (PPKE, Hungary)Phonology and morphology in the nineteenth century: the issue of abstractness vs. empiricism [This talk discusses the changing roles of phonology and morphology throughout the nineteenth century and the way the focus shifted from the latter to the former beginning with the 1870’s, one of the most remarkable periods in the development of modern linguistics. This shift was a very important aspect of the Paleogrammarian-Neogrammarian transition, an aspect that has not so far got the attention it deserves. It is also closely connected to the role abstraction played in the work of the different generations of linguists. The open conflict between the Paleogrammarians and the Neogrammarians as well as the latent conflict between the Neogrammarians and de Saussure was partly grounded in different perceptions of what constituted unwarranted abstraction, an issue that is still very much with us in linguistics.]
- Martin Kraemer will be giving a short special course on Underlying Representations in Phonology open to all students and staff. There are two sessions on this: Monday 17th February (13.10-15.00) and Wednesday 19th February (13.10-15.00), both in room 1.17. All are welcome to turn up to these sessions - no booking necessary.