Building on information processing models of first language production, second language researchers conceptualized L2 learners' conversational discourse as a process of encoding, decoding and modifying some mental abstractions of the target language. However, with the reinvestigation of the works of the Russian psychologist and semiotician Lev Vygotsky s sociocultural theory (SCT), Second language acquisition researchers started to realize the inadequacy of that perspective of verbal interaction to account for the complex process of language acquisition. Accordingly, the act of interaction was no longer seen as a by-product of learning, but rather as a manifestation that the learning process itself is taking place.