The purpose of the present study is to investigate similarities and differences in the listening behaviors of native speakers and learners of Japanese, focusing on the production of aizuchi and head nods. The term aizuchi is often interchangeably used with the word backchannel, and these are characterized as the listener's use of short utterances such as oh or uh huh in English or hai, un, or aa in Japanese. In this study, aizuchi is defined as a short verbal utterance that is produced in response to the primary speaker's speech in Japanese. A total of 14 NS--NS or 14 NS--NNS dyads were formed to elicit native speakers' and learners' aizuchi and head nods. With the exception of a few participants in their late twenties, most of the participants were female native speakers and learners of Japanese who were of college age. The learners of Japanese were native speakers of American English who had been labeled as intermediate/high-intermediate level learners of Japanese. Each interaction included a semi-free conversation and a narrative story-telling task, both of which were recorded and transcribed for analysis. The findings indicate that the differences in the use of aizuchi and head nods produced by native speakers and learners lie not mainly in their frequency, but in the types and functions. The results show that when the frequency of aizuchi and head nods was measured with a time-based scale, which was the frequency per 60 seconds, differences were found in the frequency of head nods and total frequency of aizuchi and head nods. However, no significant difference was found in the frequency of aizuchi and head nods based on the amount of speech the speakers produced. Aizuchi were categorized into 16 groups to investigate differences in their types. The results show that the learners were using less aa-group, hee-group, iya-group aizuchi but more soo-group aizuchi compared to the native speakers. The number of different aizuchi each participant used was also measured to examine the variety of aizuchi, and it was found that both the native speakers and the learners were producing a similar number of different aizuchi. Head nods were analyzed based on nodding count, and it was revealed that more multiple head nods were observed in the learner's behaviors. The functions of aizuchi and head nods were categorized into seven groups, and the distribution of the functions was analyzed. The results indicate that learners tend to use more aizuchi to express their understanding and reaction to their interlocutors' response solicitation, while the use of aizuchi that do not show their attitude was more frequent with native speakers. The distribution of the functions of head nods was similar between the two groups. By further examining the types and the function of aizuchi and head nods, the study sheds light on which types of aizuchi learners may be lacking or overusing. Pedagogical implications are drawn from the results.

The efficacy of aural modeling in music education at the primary and secondary levels is well documented, and anecdotal evidence among university studio voice teachers abounds. However, this topic has not previously been explored with undergraduate level singers using acoustic analysis of the singing voice. This investigation utilized a survey on listening behaviors to examine undergraduate voice students’ use of recorded aural models. In addition, an empirical study measured the effect of repeated exposure to recorded aural models on participants’ vocal production. Research was conducted at Southwestern University, a private liberal arts institution in Georgetown, Texas. Study participants were divided into two groups. The control group performed a newly-composed melody after a recorded aural model of the melody was played a single time. The experimental group completed 10-minute listening assignments once a day for a five-day period before performing the same melody. Data between the non-listening and listening groups was compared. Using a second newly composed melody, the control group then completed a five-day listening assignment and performed the second melody. Pre- and post-listening data from this group of subjects was compared. Listening assignments were adapted from a speech pathology remediation technique known as auditory bombardment. They involved listening to multiple repetitions of the recorded aural model without attempting to practice singing the melody. The study measured four acoustic parameters: musical accuracy (pitch and rhythm), vowel/consonant articulation, use of vibrato, and ratio of power between overtones above and below 2 kHz. The listening behavior survey revealed that most students use recorded aural models in their practice time. However, results indicated that students would benefit from professional quality aural models and specific information about appropriate time parameters for listening activities. Results of the empirical study revealed a statistically significant 20-30% improvement in vocal production in both the experimental listening group and the control group post-listening. These data demonstrate that focused periods of listening to an aural model are effective in improving vocal production, even within a short period of time. The results of this study support the inclusion of aural modeling in the applied voice studio. / text