Schramm’s Interactive Model, 1954
Wilbur Schramm (1954) was one of the first to alter the mathematical model of Shannon and Weaver. He conceived of decoding and encoding as activities maintained simultaneously by sender and receiver; he also made provisions for a two-way interchange of messages. Notice also the inclusion of an “interpreter” as an abstract representation of the problem of meaning.
(From Wilbur Schramm, “How Communication Works,” in The Process and Effects of Communication, ed. Wilbur Schramm (Urbana: University of Illinois Press, 1954), pp. 3-26):