Coordination of fingers and speech
Gloria Jones Borden, Joy Armson · The Journal of the Acoustical Society of America · 1985
Contact between fingers and thumb on a task of counting on one's fingers was related to lip/jaw and laryngeal movements while simultaneously counting aloud. Finger contacts were measured from the onset of a voltage produced as the contact completed a circuit. Speech movements were inferred from the deflections of a LED attached to the lower lip of the speaker and from the slow and fast (filtered) impedance changes recorded by an electroglottograph. Subjects counted 20 four-digit number series composed of the numbers 2, 3, 4, and 5. They were instructed to simultaneously count aloud and on their fingers, the second task providing more uncertainty than the first. Results showed that subjects timed finger contacts most closely with the movements of lip/jaw lowering and vocal fold adduction preparatory to voicing, rather than with voicing itself. These results add physiological evidence to acoustic data previously reported by G. Allen [Lang. Speech 15, 72–100 (1972)], K. Rapp [Pap. Linguist., Univ. Stockholm 8, 14–19 (1971)], and C. A. Fowler and L. G. Tassinary [Attention and Performance IX, edited by Long and Baddeley (Erlbaum, Hillsdale, NJ, 1981), pp. 521–535] indicating that the systems may be coordinated on the basis of the most dynamic parts of the utterance rather than the relatively steady state portions. [Work supported by NIH.]