あいづち -- 相槌 or sometimes 相鎚

Graphic from "Etymology question: aizuchi in linguistics" by Neill Walker (December 10, 2009), edited by Janet R. Goodwin in H-JAPAN (Humanities and Social Sciences NET on-line) http://h-net.msu.edu/cgi-bin/logbrowse.pl?trx=vx&list=h-japan&month=0912&...


Are these discourse verbalizations (plus ?)

interjections, "supportive communication (per LY),"

interruptions, "collaborative communication,"

back-channels, interactive channels,

or

required meta-discourse comments that demonstrate "active listening"?


A form of turn-taking using key phrases (and movements) at transition relevance places (TRPs) (LY)
Compare to taarof (wikipedia)
and ASL squints (me)
and "Southern codes" (LA Times on Taarof)

https://en.wikipedia.org/wiki/Aizuchi
[aizu͍t͡ɕi] (IPA)

tʃ ?

In what way are they, "more pronounced and important in Japanese"?
Cf. English "Yeah, yeah", "OK", "got it", "yep", "uh-huh" (I modified Wikipedia's list)

Aizuchi-shmaizuchi, are you out-to-lunch? Americans aren't empathic enough for you? Duh!

The Japanese counterparts indicate participation with an assumed emotional state of interest, not derision. For example, the one-word English utterance "Duh!" has a characteristic intonation indicating that the speaker wishes the other party to know that s/he just said was so obvious that it does not deserve further comment. "Duh!" demonstrates active listening no less than "Uh-huh," but it might serve to curtail the conversation rather than continue it.

Bloomfield in 1984 (as cited by Kockelman in 2003, pp 469-470) maintains that four criteria distinguish interjections as an identifiable word form within a language: they serve as stand-alone utterances with standard pronunciation; they don't combine with other morphemes for tense, number, etc; they may have sound patterns that are unusual for their language's phonetic inventory (e.g. the word-initial glottal stop in "uh-huh"): and they rarely combine with other parts of speech.

http://web.uri.edu/iaics/files/06-Laura-Miller.pdf
Univ of Rhode Island 1991 paper based on 1988 UCLA dissertation in INTERCULTURAL COMMUNICATION STUDIES
............"From native speaker descriptions of conversational behavior it is apparent that aizuchi is thought of as a way of displaying empathy. It is possible that because American verbal listening behavior is not expressed as consciously, or frequently, as it is for Japanese, Americans are therefore perceived by some Japanese as showing less empathy and rapport in conversation.
............"However, since empathy is an important social behavior in all cultures, it is not that Americans express empathy less than Japanese do. They are simply expressing it differently. Some methods used other than verbal listening tokens are facial expression, eye gaze, intonation, conversational collaborations and complimenting."

Aizuchi: A Beginner's Guide to Japanese Grunting Etiquette ... www.fluentu.com/japanese/blog/aizuchi/

"...according to renowned linguist Laura Miller, Japanese listeners interject with aizuchi two or three times more often than English speakers do!"

Suggested exploratory readings (via LY) one-time use
More Tannen search
English CA bibliography from SDSU course COM665 here