Natke, U., Kalveram, K.Th., & Jäncke, L. (1997) The electroglottographic signal as a device for stuttering evaluation. In: Hulstijn, W., Peters, H. & van Lieshout, P. (Eds.): Speech production: Motor Control, Brain Research and Fluency Disorders. Amsterdam: Elsevier Science Publishers, 429-437.
The electroglottographic (EGG) signal is related to temporal alterations of the vocal fold contact area. Combined with the acoustic speech signal it uncovers the working mechanisms of the phonatory apparatus. Today's computer equipment provides an easy to handle and low cost two-channel recording technique to pick up the EGG and acoustic speech signal in parallel. These records can be used to extract direct and derived parameters from both signals like voice onset time, open quotient, or degree of audio-phonatoric coupling. With regard to stuttering, this technique is useful as a training aid, with which ongoing speech production can be monitored. In addition, this equipment provides feedback of speech related parameters, for instance those indicating gentle onset, "pull-out", or vocal fry. These measurements are useful to evaluate progress during therapeutical interventions. We here give examples of speech- and EGG-recordings of stutterers and some hints concerning computerized analysis of these signals. It is concluded, that this noninvasive technique for investigation of laryngeal behavior is useful both for research and therapy.