The effects of backchannels on fluency in L2 oral task production

This article reports on an experimental study that investigated the effect of different conditions of listener backchannels on the fluency of L2 speakers. Participants were 14 non-advanced Japanese learners of English who each performed three oral tasks in three different backchannel conditions: (1) verbal/nonverbal (V/NV), (2) nonverbal-only (NV), and (3) no backchannels (NB). Verbal backchannels included ‘mm-hm’ and ‘uh-huh’ while the nonverbal backchannels involved head nodding. Fluency was assessed via five temporal measures. As hypothesized, the results showed that the 14 Japanese participants were, on average, most fluent in the V/NV condition, less fluent in the NV condition and least fluent in the NB condition. The differences obtained in fluency between the V/NV and NB conditions were found to be significant. These results lend support to the ‘backchannel output hypothesis’ which suggests that backchannels may facilitate the fluency of non-advanced learners of English during oral tasks depending on the nature of backchannel use in their L1 and sociocultural environments.