Study fora Practical Use of an Electolarynx with a Pitch Control Function Using Expiration

电喉是为无法掌握其他替代语言的人提供的一种人工喉头。然而，这种假体很难产生语音信息，如语调和口音。为了改进传统的电喉，我们提出了一种新的方法，可以让喉切除术患者通过呼吸来控制语音语调。这个装置由三部分组成。第一部分是一个压力传感器，它可以检测由颈部手术切口形成的气孔产生的呼气压力。第二部分是转换电路，可以将气压转换为声音的音高频率。第三部分是可以附着在颈部的机电振动器。该方法通过以下两个实验作为一个变换函数的参数进行了评估。第一个是测量喉切除者呼吸控制音高的准确性的实验，第二个是关于电喉音自然程度的心理物理实验。由实验结果可知，最优变换函数为F=60+25xP，其中F为基音频率，单位为Hz， P为cmH20的呼气压力。经过一天的训练，电喉音的音高模式与正常受试者的音高模式明显相似。我们决定为那些不能掌握替代语音或刚刚切除喉部的人制造这种新设备。

An electrolarynx is one of the artificial larynges for people who have failed to master the other substitute speech. However, this prosthesis makes it difficult to produce phonetic information such as intonation and accent. In order to improve a conventional electrolarynx, we have proposed a new method that can allow laryngectomees to control voice intonation by using their respiration.This device consists of three parts. The first part is a pressure sensor that can detect expiration air pressure produced from a stoma made by a surgical incision into the neck. The second part is a transformation circuit that can convert air pressure into a pitch frequency for voice. The third part is an electromechanical vibrator that can be attached to the neck. This method was evaluated through the following two experiments as a parameter of a transform function. The first one was an experiment to measure the accuracy of pitch control using the respiration of laryngectomees and the second one was psychophysical experiments regarding the degree of naturalness of the electrolarynx voice.From the experimental results, the optimal transform function was found to be F=60+25xP,where F is the pitch frequency in Hz and P is the expiration pressure in cmH20. The pitch pattern of the electric larynx voice became clearly similar to the pattern produced from a normal subject after one day training. We have decided to manufacture the new device for the people who can not master the substitute speech or have just had their larynx removed.