Fu Qian-Jie, Hsu Chuan-Jen, Horng Mei-Ji
Department of Auditory Implants and Perception, House Ear Institute, 2100 West Third Street, Los Angeles, CA 90057, USA.
Ear Hear. 2004 Oct;25(5):501-8. doi: 10.1097/01.aud.0000145125.50433.19.
To evaluate the effects of speech processing strategy on Chinese tone recognition by Nucleus-24 cochlear implant users.
Recognition of Chinese tones was measured with the spectral peak (SPEAK), advanced combination encoders (ACE), and continuous interleaved sampling (CIS) strategies in nine Nucleus-24 cochlear implant users. Recognition of Chinese sentences was also measured with the ACE strategy (1200 pulse-per-sec on each electrode). As the stimulation rate in the SPEAK processor is fixed at 250 pulses per sec per electrode (ppspe), only one stimulation rate was tested with the SPEAK processor. Three stimulation rates (900, 1200, and 1800 ppspe) were tested in the ACE processing conditions. Four stimulation rates (1200, 1800, 2400, and 3600 ppspe) were tested in the CIS processing conditions. Because the number of stimulating electrodes determines the stimulation rate in CIS processors, the number of electrodes was reduced from 12 to 8 to 6 to 4 to achieve stimulation rates of 1200, 1800, 2400, to 3600 pps.
Results showed that mean Chinese tone recognition scores with the ACE and CIS strategies were significantly higher than those with the SPEAK strategy. For the ACE strategy, there was no significant difference in performance among the various stimulation rates (for the ACE processing conditions, the stimulation rate was varied while keeping the number of stimulating electrodes constant). For the CIS strategy, there was no significant difference among the various stimulation rates and electrode configurations (for the CIS processing conditions, the stimulation rate was varied by changing the number of stimulating electrodes). There was also a significant correlation between Chinese tone recognition and the recognition of everyday sentences.
The latest-generation speech processing strategies were able to provide cochlear implant users with considerable amounts of tonal information. However, Chinese tone recognition was significantly affected by the choice in speech processing strategy. Relatively higher stimulation rates (>900 ppspe) may improve Chinese tone recognition. Furthermore, it may be necessary to develop speech processing strategies to specifically improve tone recognition, which is critical for understanding tonal languages.
评估言语处理策略对Nucleus-24型人工耳蜗使用者汉语声调识别的影响。
对9名Nucleus-24型人工耳蜗使用者采用谱峰（SPEAK）、高级组合编码（ACE）和连续交错采样（CIS）策略测量汉语声调识别。还采用ACE策略（每个电极每秒1200个脉冲）测量汉语句子识别。由于SPEAK处理器的刺激速率固定为每个电极每秒250个脉冲（ppspe），因此仅对SPEAK处理器测试了一种刺激速率。在ACE处理条件下测试了三种刺激速率（900、1200和1800 ppspe）。在CIS处理条件下测试了四种刺激速率（1200、1800、2400和3600 ppspe）。由于刺激电极的数量决定了CIS处理器中的刺激速率，因此将电极数量从12个减少到8个再到6个再到4个，以实现1200、1800、2400到3600 pps的刺激速率。
结果显示，采用ACE和CIS策略时的汉语声调识别平均得分显著高于采用SPEAK策略时的得分。对于ACE策略，不同刺激速率下的表现无显著差异（对于ACE处理条件，在保持刺激电极数量不变的情况下改变刺激速率）。对于CIS策略，不同刺激速率和电极配置之间无显著差异（对于CIS处理条件，通过改变刺激电极数量来改变刺激速率）。汉语声调识别与日常句子识别之间也存在显著相关性。
最新一代言语处理策略能够为人工耳蜗使用者提供大量的声调信息。然而，汉语声调识别受到言语处理策略选择的显著影响。相对较高的刺激速率（>900 ppspe）可能会改善汉语声调识别。此外，可能有必要开发专门用于改善声调识别的言语处理策略，这对于理解声调语言至关重要。
