Although current communication media facilitate interactions among individuals, researchers have warned that human relationships built through these media tend to lack the level of intimacy acquired through face-to-face communications. In this study, we investigate how the long-term use of humanlike communication media affects the development of intimate relationships between human users. We examine changes in the relationship between individuals while they converse with each other through humanlike communication media or mobile phones for approximately a month. The intimacy of their relationship was evaluated using the amount of self-disclosed personal information. The result shows that a significantly greater amount of self-disclosure is made through a communication medium with humanlike appearance and soft material compared with the use of a typical mobile phone. The amount of self-disclosure showed cyclic variation in the experiment through humanlike communication media. Furthermore, we discuss a possible underlying mechanism of this effect from the misattribution of a feeling caused by intimate distance with the medium to a conversation partner.

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