William S. Condon is a researcher who investigated human interactions.
He developed the concept of situation synchrony.
[1] In Malcolm Gladwell's 2000 book, The Tipping Point, he cites Condon's research to help explain why some "Salesman" types may contribute more to word-of-mouth cultural 'epidemics'.
Some other reference is made in Flora Davis's book "Inside Intuition-What we know about Non-Verbal Communication" published in New York by McGraw-Hill Books, which talks about the study he did on Interactional Syncrony.
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