The roots of the interactionist approach can be traced to several lines of research that began in the 1970s. At this time, researchers became increasingly interested in the types of discourse patterns found in native speaker and learner conversations. In particular, they examined “foreigner talk” and the ways in which native speakers modified their speech so as to make it more comprehensible for learners (e.g., Ferguson, 1971). Paralleling a similar line of work in first language acquisition (which examined caretaker talk and the ways in which parents modified their speech for young children), researchers in this area argued that modifications such as repetition and syntactic simplifications served to make the input more comprehensible to second language (L2) learners, and in this way promoted the acquisition of the target language.
This focus on input and comprehensibility could also be found in another strand of research that influenced the development of the interactionist
approach: Krashen's Input Hypothesis (Krashen, 1977, 1980). According to this hypothesis, input that was comprehensible (but slightly above the learner's current level of proficiency) was the driving force behind language acquisition. In Krashen's view, if a learner was exposed to this type of input, and, at the same time, had a “low affective filter” (i.e., low levels of anxiety and negative feelings associated with learning the L2), acquisition of the non-native language would automatically (i.e., subconsciously) take place. For Krashen, any mechanism that served to make the input comprehensible (e.g., simplifying the grammar of a written or oral text) was of value; however, interaction between native speakers and learners did not hold any special place in his theories.
However, from the late 1970s researchers began to accord more importance to interaction itself. Wagner-Gough and Hatch (1975), for example, maintained that researchers needed to examine “the relationship between language and communication if we are looking for explanations of the learning process” (p. 307), while Hatch (1978a, 1978b) argued that interaction might be an actual site for L2 learning and not just a means of observing what had already been learned. In Hatch's (1978b) words, “one learns how to do conversation, one learns how to interact verbally, and out of the interaction syntactic structures are developed” (p. 404).
Drawing upon the work of these researchers, Long formulated his initial version of what became known as the Interaction Hypothesis (Long, 1980, 1981). In Long's view, both comprehensible input and L2 development stemmed from the conversational modifications that occurred when native speakers and non-native speakers (NNS) worked to resolve a communication difficulty. Although these modifications (commonly referred to as interactional adjustments during negotiation for meaning) were not, of course, the only means of achieving message comprehensibility, Long suggested these modifications were positioned to promote comprehensible input, and, ultimately, L2 acquisition.
Early research using the interactionist approach framework sought to describe the frequency and types of interactional modifications used in native speaker-learner and learner-learner pairings, examine the relationship between negotiation of meaning and learners’ comprehension, and compare the effects of premodified and interactionally modified input (e.g., Doughty and Pica, 1986; Gass and Varonis, 1985, 1986; Long, 1983a, b; Loschky, 1994; Pica and Doughty, 1985; Pica et al., 1987; Porter, 1986; Varonis and Gass, 1985). As several researchers, including Mackey (1999), Ellis (1999) and Spada and Lightbown (2009), pointed out, this early research tended to be descriptive and did not seek to provide direct evidence that interaction
was causally linked to L2 acquisition.
Early versions of the Interaction Hypothesis incorporated Krashen's claims about comprehensible input being necessary and sufficient for development in the L2: “Access to comprehensible input is a characteristic of all cases of successful acquisition, first and second ... greater quantities of comprehensible input seem to result in better (or at least faster) acquisition ... and crucially, lack of access to comprehensible input ... results in little or no acquisition” (Long, 1983b, p. 210). However, a number of researchers took issue with Krashen's claims about comprehensible input and SLA. Swain (1985, 1995), for example, argued that while comprehensible input was necessary for L2 acquisition to occur, it was far from sufficient. Based on her work with French immersion students in Canada, she argued that if learners do not have regular opportunities to speak or write the language (that is, to produce output), their production skills (speaking and writing) would lag considerably behind their comprehension skills (listening and reading). This observation served as the starting point for Swain's Output Hypothesis (1985), which posits that producing output plays a crucial role in the development of the L2, as it (a) gives learners the opportunity to practice and thus to automatize the production of the language; (b) allows learners to test hypotheses concerning the L2; (c) forces learners to focus on structure of the language; and (d) draws learners’ attention to gaps in their interlanguage (1995; see also Swain, 2005). Swain suggested that second language learners need to be pushed to produce output, arguing that “being pushed in output, it seems to me, is a concept parallel to that of the i + 1 of comprehensible input. Indeed, one might call this the comprehensible output” (1985, p. 249). As we discuss later in this chapter, Swain's Output Hypothesis is subsumed in later versions of the Interaction Hypothesis.
The idea of comprehensible input being insufficient for second language acquisition was also discussed by White (1991, 2003). Approaching the role of input from a different theoretical perspective, White claimed that it is unlikely that French learners of English acquire the rule that delimits adverb placement in English (the strict adjacency principle in case assignment) with positive evidence alone because the positive evidence they receive does not contain the information that what is acceptable in French adverb placement may not be acceptable in English. To elaborate, in English, adverbs cannot be placed between the verb and the direct object (thus “Mary watches often television” is ungrammatical). However, the same word ordering —V Adv O —is possible in French (“Mary regarde souvent la television”). Thus, drawing upon his/her L1, the native speaker of French learning English might assume that a sentence such as “Mary watches often television” is acceptable because
positive evidence (i.e., English input) provides no information about non- acceptable utterances. White points out that if a learner were solely dependent on comprehensible input for making progress in the L2, they would have to notice the absence (referred to as indirect negative evidence) of a particular structure (for example, the V Adv O structure in English). While this is theoretically possible, the language acquisition process may be facilitated if the learner receives assistance in the form of correction or instruction. In essence, what White argued was that comprehensible input is insufficient for certain aspects of L2 development. However, as we will see below and in Chapter 2, the interactionist approach takes into account the important construct of feedback that helps to account for how learners receive information about incorrect utterances.
Other extensions of the Interaction Hypothesis grew out of points made about the role of attention in second language learning. Work in the early 1990s proposed that only consciously noticed features of the input became intake (e.g., Schmidt, 1990, 1993). According to Schmidt's Noticing Hypothesis, “subliminal language learning is impossible, and ... noticing is the necessary and sufficient condition for converting input to intake” (1990, p. 129) (see also Chapter 15). Researchers were quick to point out, however, that L2 learners’ input processing strategies might make certain portions of the L2 difficult to notice. As VanPatten (1989) noted, L2 learners typically practice a form of selective attention, focusing on a limited and thus less overwhelming portion of the input. Those aspects of the input that are salient and meaningful are typically those that draw the learners’ attention; features that lack saliency or communicative value (such as determiners in English, gender agreement in Spanish, or postpositions in Japanese) may pass under the learner's radar, so to speak. For this reason, researchers argued, L2 learners might benefit from having their attention drawn to formal features of the target language. This claim, too, made its way into a later version of the Interaction Hypothesis.
Drawing upon the work of these researchers, Long presented a reformulated version of the Interaction Hypothesis in 1996, which stated that “Negotiation for meaning, and especially negotiation that triggers interactional adjustments by the native speaker or more competent interlocutor, facilitates acquisition because it connects input, internal learner capacities, particularly selective attention, and output in productive ways” (p. 451). The following section deals with the major tenets of the most recent updates of this approach (Gass and Mackey, 2007a), along with current research.