Backchannel (linguistics)

In linguistics, backchannels are listener responses in a primarily one-way communication. These can be both verbal and non-verbal in nature, and are frequently phatic expressions, primarily serving a social or meta-conversational purpose, rather than involving substantial two-way communication.

The term "backchannel" was designed to imply that there are two channels of communication operating simultaneously during a conversation. The predominant channel is that of the speaker who directs primary speech flow. The secondary channel of communication (or backchannel) is that of the listener which functions to provide continuers or assessments, defining a listener's comprehension and/or interest.

Due to research development in recent years, backchannel responses have been expanded to include sentence completions, requests for clarification, brief statements, and non-verbal responses and now fall into three categories: non-lexical, phrasal, and substantive. A non-lexical backchannel is a vocalized sound that has little or no referential meaning but still verbalizes the listener's attention. In English, sounds like "uh-huh" and "hmm" serve this role. Phrasal backchannels most commonly assess or acknowledge a speaker's communication with simple words or phrases (for example, "Really?" or "Wow!" in English). Substantive backchannels consist of more substantial turn-taking by the listener and usually manifest as asking for clarification or repetitions.

The term was coined by Victor Yngve in 1970, in the following passage: "In fact, both the person who has the turn and his partner are simultaneously engaged in both speaking and listening. This is because of the existence of what I call the back channel, over which the person who has the turn receives short messages such as 'yes' and 'uh-huh' without relinquishing the turn."

Backchannel communication is present in all cultures and languages, though frequency and use may vary. Confusion or distraction can occur during an intercultural encounter if participants from both parties are not accustomed to the same backchannel norms.

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