101). The debate about the definition of term 'collaborative' as well as ongoing attempts to identify relevant criteria to determine whether learning is collaborative or not does not seem to have any major implications for the basics of collaborative learning.
Almost every research study exploring collaborative learning environment comes to positive conclusions (Johnson, Johnson, and Stanne, 1986; Natasi and Clements, 1991). Natasi and Clements (1991) summarize these conclusions in the following way: "Cognitive-academic and social-emotional benefits have been reported for students from early elementary through college level, from diverse ethnic and cultural backgrounds, and having a wide range of ability levels Furthermore, cooperative learning has been used effectively across a wide range of content areas, including mathematics, reading, language arts, social studies and science" (p. 111).
Initially, research in the realm of collaborative learning focused on functioning of an individual learner in a group: the theories which dominated cognitive psychology over the 1970s tended to emphasise the role of individual information processors in the process of cognition. The social context of this process was viewed as secondary to individual activity (Dillenbourg et al, 1996: 189). The last decades of the 20th century were marked by increased attention to the social context, and, consequently, improved understanding of the process of cognition. Much of the shift was due to growing influence of sociocultural theory in pedagogical practice. This theory is very helpful in predicting, explaining and justifying the above listed cognitive, psychological and social benefits of engaging students in collaborative learning activities
The theoretical background underlying contemporary models of collaborative learning relies heavily upon three major theories of learning: socio-constructivist theory, socio-cultural theory, and shared cognition theory (Dillenbourg et al, 1996). These three perspectives share the basic features of cognitive stance, including the focus on the interactive aspect of human development and learning, but the socio-cultural theory has been recently gaining momentum as the most influential among the three in the realm of language education (Lantolf, 2000; Wells, 1999).
L. S. Vygotsky formulated the basics of socio-cultural theory in the 1920s and 1930s, though current conceptualisations of this approach also draw on works and ideas of other theorists (Luria, 1979; Wertsch, 1991, 1998; Newman and Holzman, 1993; Cole, 1996). The essence of socio-cultural theory is exploring the causal relationship between the social interactions and cognitive