One of the most fundamental problems in research on spoken language is to understand how the categorical, systemic knowledge that speakers have in the form of a phonological grammar maps onto the continuous, high-dimensional physical speech act that transmits the linguistic message. The invariant units of phonological analysis have no invariant analogue in the signal—any given phoneme can manifest itself in many possible variants, depending on context, speech rate, utterance position and the like, and the acoustic cues for a given phoneme are spread out over time across multiple linguistic units. Speakers and listeners are highly knowledgeable about the lawfully structured variation in the signal and they skillfully exploit articulatory and acoustic trading relations when speaking and perceiving. For the scientific description of spoken language understanding this association between abstract, discrete categories and continuous speech dynamics remains a formidable challenge. Articulatory Phonology and the associated Task Dynamic model present one particular proposal on how to step up to this challenge using the mathematics of dynamical systems with the central insight being that spoken language is fundamentally based on the production and perception of linguistically defined patterns of motion. In Articulatory Phonology, primitive units of phonological representation are called gestures. Gestures are defined based on linear second order differential equations, giving them inherent spatial and temporal specifications. Gestures control the vocal tract at a macroscopic level, harnessing the many degrees of freedom in the vocal tract into low-dimensional control units. Phonology, in this model, thus directly governs the spatial and temporal orchestration of vocal tract actions.
Arthur Seymour Abramson (1925–2017) was an American linguist who was prominent in the international experimental phonetics research community. He was best known for his pioneering work, with Leigh Lisker, on voice onset time (VOT), and for his many years spent studying tone and voice quality in languages such as Thai. Born and raised in Jersey City, New Jersey, Abramson served several years in the Army during World War II. Upon his return to civilian life, he attended Columbia University (BA, 1950; PhD, 1960). There he met Franklin Cooper, an adjunct who taught acoustic phonetics while also working for Haskins Laboratories. Abramson started working on a part-time basis at Haskins and remained affiliated with the institution until his death. For his doctoral dissertation (1962), he studied the vowels and tones of the Thai language, which would sit at the heart of his research and travels for the rest of his life. He would expand his investigations to include various languages and dialects, such as Pattani Malay and the Kuai dialect of Suai, a Mon-Khmer language. Abramson began his collaboration with University Pennsylvania linguist Leigh Lisker at Haskins Laboratories in the 1960s. Using their unique VOT technique, a sensitive measure of the articulatory timing between an occlusion in the vocal tract and the beginning of phonation (characterized by the onset of vibration of the vocal folds), they studied the voicing distinctions of various languages. Their long standing collaboration continued until Lisker’s death in 2006. Abramson and colleagues often made innovative use of state-of-art tools and technologies in their work, including transillumination of the larynx in running speech, X-ray movies of speakers in several languages/dialects, electroglottography, and articulatory speech synthesis. Abramson’s career was also notable for the academic and scientific service roles that he assumed, including membership on the council of the International Phonetic Association (IPA), and as a coordinator of the effort to revise the International Phonetic Alphabet at the IPA’s 1989 Kiel Convention. He was also editor of the journal Language and Speech, and took on leadership roles at the Linguistic Society of America and the Acoustical Society of America. He was the founding Chair of the Linguistics Department at the University of Connecticut, which became a hotbed for research in experimental phonetics in the 1970s and 1980s because of its many affiliations with Haskins Laboratories. He also served for many years as a board member at Haskins, and Secretary of both the Board and the Haskins Corporation, where he was a friend and mentor to many.