The Motor Theory of Speech Perception is a proposed explanation of the fundamental relationship between the way speech is produced and the way it is perceived. Associated primarily with the work of Liberman and colleagues, it posited the active participation of the motor system in the perception of speech. Early versions of the theory contained elements that later proved untenable, such as the expectation that the neural commands to the muscles (as seen in electromyography) would be more invariant than the acoustics. Support drawn from categorical perception (in which discrimination is quite poor within linguistic categories but excellent across boundaries) was called into question by studies showing means of improving within-category discrimination and finding similar results for nonspeech sounds and for animals perceiving speech. Evidence for motor involvement in perceptual processes nonetheless continued to accrue, and related motor theories have been proposed. Neurological and neuroimaging results have yielded a great deal of evidence consistent with variants of the theory, but they highlight the issue that there is no single “motor system,” and so different components appear in different contexts. Assigning the appropriate amount of effort to the various systems that interact to result in the perception of speech is an ongoing process, but it is clear that some of the systems will reflect the motor control of speech.
D. H. Whalen
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.