Tungans muskelaktivitet vid stamning : En kvalitativ studie med elektromyografi

Sammanfattning: Stuttering is a speech disorder which involves recurrent disruptions of the fluency of speech. Previous research has investigated movements of the tongue during stuttering, but this excludes answers regarding the underlying activity of the muscles. This study was created for two purposes: partly to investigate the role of the tongue in stuttering, partly to design a method suitable for observing this. EMG-electrodes were placed on the lips and tongue. The electrode placed on the tongue was attached with glue intended for the oral cavity, PeriAcryl. Using this method registrations were carried out, but many application attempts were required and low impedance was difficult to achieve. Registrations appeared to be stronger in the articulation of phonemes and syllables involving the front of the tongue. When processing collected data, new categories were designed in an attempt to augment the traditional, acoustically categorised core behaviours (i.e. repetitions, prolongations and blockages). The results in this study show that the tension of the tongue has a great influence on how and why occasions of stuttering occur. In several participants, elevated levels of static tension were registered which resulted in a blockage of the oral cavity, e.g. /d/. In other cases of blockage of the oral cavity, air passed through the nasal cavity, creating nasal sounds. Spreading of muscle tension between oral and facial muscles could be observed in a number of participants, which was also reflected in accessory movements (e.g. eye blinking, twitching and frowning). Low muscle tension was measured in occasions that could be described as insufficient articulation. Signs of tremor in the tongue were observed in one participant in this study. The method had several successful attempts and provided analysable measurements, but questions about its stability and the size of the group prevent generalisation of the results.