2019 年 90 巻 3 号 p. 301-307
This study investigated the effect of the type of backchannel utterances (BU) on idea generation. Three types of BU were affirmative, neutral, and non-affirmative. Two categories of task were predicting consequences and devising resolutions. Thirty undergraduate students participated in the present experiment. Dependent variables were the number of ideas generated, speaking time, motivation of speakers, and speakers’ perception of listeners’interest in, agreement with, and admiration of speakers’ ideas. The main results were as follows: (a) affirmative BU was significantly effective for idea generation only in the prediction task, and (b) affirmative BU was effective for other dependent variables in both tasks. These findings showed the effectiveness of affirmative BU as a strategy for facilitating idea generation. The interaction of BU type and task was interpreted in terms of the possibility that the two kinds of tasks involved different thinking processes. Because the interaction was found only for idea generation, it was suggested that BU had two influencing pathways: increasing motivation through positive affect and activating idea generation itself.