The role of kinesthesis in the organization of speech organ movement

摘要

This thesis investigates position sense in the tongue and the role of kinesthesis in organizing voluntary rhythmic human finger movements and the repetition of monosyllables. -- Four experiments showed that a sense of the tongue's position inside and outside the mouth in horizontal and vertical planes exists, and is similarly accurate to that of the limbs (error: 2°). Subjects misjudged the position of their tongue following loading of the tongue. Anesthesia of the mucosa did not reliably reduce the accuracy of lingual position sense. The sources of positional information that contribute to position sense in the tongue and limb are similar; muscle, tendon, skin and knowledge of efference. -- Six experiments revealed that finger movements and monosyllable repetition entrained to an imposed, irrelevant kinesthetic rhythm in about 30% of the data, although subjects were not instructed to entrain their finger movements or speech to the kinesthetic stimulus rhythms. As entrainment should not have arisen at all unless the organization of both finger movement and monosyllabic speech has the character of a system of non-linear oscillators, this is a powerful finding. -- The entrainment commonly features a slight anticipation of antiphase of the kinesthetic stimulus using both finger movement and speech tasks. Subjects entrained their speech and finger movements to the stimulus rhythms equally often, upholding the thesis that, at a fundamental level, speech and finger movements are organized similarly. Kinesthetic information is used to organize voluntary limb and speech movements.