返回Google圖書搜尋

Inhibition of Stuttering from Second Speech Signals: an Evaluation of Temporal and Hierarchical Aspects

出版	East Carolina University, 2012
URL	http://books.google.com.hk/books?id=NEJxAQAACAAJ&hl=&source=gbs_api

註釋Experiment II examined stuttering inhibition during scripted telephone conversations under altered auditory feedback. As with the lag shadow speech condition, altered auditory feedback and more specifically delayed auditory feedback, presents a second speech signal along with ongoing speech. Delayed auditory feedback and frequency-altered feedback generate second speech signals from the speakers' initial speech productions. Reductions in stuttering frequency under altered auditory feedback typically range from 60-80%. These reductions occur during the presentation of one signal and one combination of signals across a variety of settings; specifically, telephone conversations, which are judged to be one of the most hierarchically difficult situations for people who stutter. The second experiment examined nine people who stutter during 15 scripted telephone conversations under baseline, one combination of DAF and FAF (i.e., 50 ms delay and ℗ư octave shift up respectively; 1 COMBO), and two combinations of DAF and FAF (i.e., 1 COMBO plus 200 ms delay and ℗ư shift down respectively; 2 COMBO). Stuttering was significantly inhibited during both altered feedback conditions (i.e., 63% during 1 COMBO and 74% during 2 COMBO). Furthermore, significant reductions in stuttering frequency during the 2 COMBO conditions as compared to the 1 COMBO indicated that presentation of increased gestural information enhances the inhibitory effects. Results from both studies challenge notions put forth by previous models of stuttering reduction during the perception of second signals. The findings that stuttering was reduced to similar extents during both lead and lag conditions in Experiment I and that more robust stuttering inhibition occurred during the COMBO II condition in Experiment II, challenge fundamental notions from previous reduction theories during the perception of second signals. Furthermore, these findings support the flexible and dynamic gestural percepts hypothesized in the Gestural Model of Stuttering Inhibition. It is likely that increased gestural information alters mirror neuron system activation patterns, which enables a more efficient and effective release of the central neural block that is stuttering, therefore increasing inhibitory effectiveness from the perception of second signals.