Applied Linguistics 22/1: 1±26 # Oxford University Press 2001 Incidental Vocabulary Acquisition in a Second Language: The Construct of Task-Induced Involvement BATIA LAUFER and JAN HULSTIJN 1 University of Haifa, Israel and 2University of Amsterdam, The Netherlands The paper makes an attempt to stimulate theoretical thinking and empirical research in the domain of L2 vocabulary learning by introducing a construct of involvement with motivational and cognitive dimensions: Need, Search, and Evaluation. Retention of hitherto unfamiliar words is claimed to be conditional upon the amount of involvement while processing these words. Involvement is operationalised by tasks designed to vary in the degree of need, search, and evaluation. The paper reviews a number of constructs that are currently debated and investigated in the literature on cognitive and motivational aspects of L2 learning. It also re-examines the existing empirical literature on task eect in the light of the proposed construct of task-induced involvement, stresses the need for deepening and broadening the construct, and discusses possibilities it oers for research on vocabulary learning. Virtually all second language learners and their teachers are well aware of the fact that learning a second language (L2) involves the learning of large numbers of words. Not surprisingly, many learners are somewhat apprehensive when faced with such an enormous task and teachers as well as learners have always shown a keen interest in ®nding out how words can best be learned. For many years, instructional practice has been based on the view, unanimously supported by psychologists, that elaboration on features of new words promotes their retention (Anderson 1995: ch. 6; Baddeley 1997: ch. 7). This proposition is based on what learning psychologists have been repeating for many decades after William James (1890: 662), namely that `all improvement of the memory lies in the line of elaborating the associates'. This means that the more attention that is paid to the formal and semantic aspects of words and the richer the associations that are made with existing knowledge (e.g. in the form of establishing similarities and contrasts between old and new information), the higher are the chances that the new information will be retained. Likewise, all learners and teachers know that motivation promotes success and achievement in L2 learning and that students who experience high amounts of an external or intrinsic drive or need to learn, will achieve higher levels of pro®ciency than students with low levels of drive. In practice, this means that educationalists may attempt to increase students' motivation by 2 INCIDENTAL VOCABULARY ACQUISITION IN A SECOND LANGUAGE providing tasks and materials which students may experience as interesting and appealing. We entirely agree with the views that elaboration and motivation are key factors in promoting vocabulary learning. However, we note with some concern that the theoretical and the empirical literature on concepts of cognition in the narrow, information-processing sense (such as elaboration and attention), as well as the literature on aective components of cognition (such as motivation and need), have not produced substantial progress in the domain of L2 vocabulary learning. In this respect, theory and research on L2 vocabulary learning is lagging behind developments in the domain of L2 grammar learning, where recent years have spurred new theoretical and empirical work on constructs such as `focus on form' (e.g. Long and Robinson 1998), `input processing' (VanPatten 1996), and task-based language teaching (Skehan 1998; Robinson 2000). In this paper, we make an attempt to stimulate both theoretical thinking and empirical research in the domain of L2 vocabulary learning by proposing a construct of task-induced involvement, with three motivational and cognitive dimensions: need, search, and evaluation. We begin with a review of the literature on a number of cognitive constructs (such as attention, implicit and explicit learning, and elaboration) and we brie¯y review the literature on motivation. This is followed by a consideration of the notion of incidental learning, which is crucial for a proper understanding of the literature of incidental L2 vocabulary learning. These three ground-clearing review sections are rounded o with a brief summary. Next, we examine the empirical literature on factors promoting incidental L2 vocabulary learning. Subsequently, we present our construct of task-induced involvement load, re-examine the empirical literature in the light of this construct and end our paper with a discussion of the needs to deepen and broaden the construct both theoretically and empirically. COGNITIVE VIEWS ON THE REPRESENTATION AND ATTAINMENT OF L2 KNOWLEDGE In this section, we will ®rst look at the literature on L2 grammar acquisition (mostly referred to by `SLA', excluding vocabulary) and then review the literature on L2 vocabulary learning, examining which cognitive constructs have been invoked in these two domains. In trying to understand the SLA literature, it is helpful to distinguish between views on how grammatical knowledge is represented in the mind and views on how grammatical knowledge is acquired. With respect to the mental representation of grammatical knowledge, most researchers in the generative school conceptualise L2 grammatical knowledge as consisting of (1) a system of highly abstract principles and parameters dealing with mostly abstract grammatical phenomena such as word order, government, constraints on movement, agreement, tense, and co-reference, which are commonly referred to as Universal Grammar (UG) or as the `core', BATIA LAUFER and JAN HULSTIJN 3 and (2) the remainder, or the `periphery' of grammatical knowledge, pertaining to phenomena such as regular and irregular forms of noun declension, verb conjugation, grammatical gender, etc. With regard to the core, the discussion centres around the question of the initial state, in particular the issue of how L2 learners, given the fact that they have already set the parameters of UG for their L1, will set, or reset, or not set at all, the parameters of L2. In contrast to the symbolic view, the connectionist view represents language knowledge as a neural network, consisting of a collection of units connected to each other by a set of pathways (Broeder and Plunkett 1994). The network is the product of a bottom-up process in which lower-level units have been grouped with each other to form higher-level units. In this view, it is not necessarily the case that the network (or parts of it) embodies grammatical notions such as CP, NP, AGR, etc. Nor does the network, in comprehending or producing language, apply rules. The fact that the outcome of comprehension or production processes appears to be regular does not imply that rules have been applied. Regular behaviour can also be generated by associative processes based on the relative strength of certain connections standing in competition with the strength of other connections. It should be noted that a generative theory of grammar is only concerned with the representation of knowledge and not with its acquisition or its transition from one stage to another (Gregg 1996, 2000). Connectionists, however, deal with representation and acquisition in a single theory. This will become apparent in a later section, concerned with implicit and explicit learning. Noticing and attention With regard to the question of how grammatical knowledge is acquired, three positions are commonly distinguished (N. Ellis 1994a; R. Ellis 1993; Hulstijn and De Graa 1994), which are referred to as the No Interface, Strong Interface, and Weak Interface positions. According to these positions, explicit, metalinguistic knowledge, e.g. knowledge of the rules to be found in pedagogic grammars, does not aect the acquisition of implicit knowledge (No Interface), transfers into implicit knowledge (Strong Interface), or may indirectly aect the acquisition of implicit knowledge by focusing learners' attention on features in the input which are critical for the grammatical phenomenon to be acquired (Weak Interface). Schmidt (1994a, 1994b, 2000) further developed the Weak Interface position into his Noticing Hypothesis. The Noticing Hypothesis holds that, for L2 grammar acquisition to take place, it is not necessary to learn metalinguistic principles or rules, but that learners must `notice' critical features in utterances. In the case of subject±verb agreement, for instance, learners must notice the co-occurrence of certain subject and verb forms. Schmidt (2000) de®nes `noticing' as the subjective correlate of what 4 INCIDENTAL VOCABULARY ACQUISITION IN A SECOND LANGUAGE psychologists call attention, roughly equivalent to `clear perception' and `detection within selective attention' (Tomlin and Villa 1994; see also Carr and Curran 1994). Reviewing the psychological literature on attention, Schmidt (2000) concludes that although there may be some forms of learning without attention (the evidence on unattended learning is highly contested in the psychological literature), it is known that preparatory attention and voluntary orienting vastly improve encoding: Since many features of L2 input are likely to be infrequent, non-salient, and communicatively redundant, intentionally focused attention may be a practical (though not theoretical) necessity for successful language learning. Language learners who take a totally passive approach to learning, waiting patiently and depending on involuntary attentional processes to trigger automatic noticing, are likely to be slow and unsuccessful learners (Schmidt 2000). Schmidt argues that there is sucient ground to motivate an attentionally determined encoding-speci®city hypothesis for SLA, acknowledging that this is insucient to settle the issue of explaining the acquisition of many of the abstract features of UG. The growing interest in attention, `focus on form' (Long and Robinson 1998), `input processing' (VanPatten 1996) and `input enhancement' (Sharwood Smith 1993) has produced a still growing number of empirical studies designed to investigate which attention directing tasks may promote L2 grammar learning (e.g. Doughty 1991; Harley 1998; Hulstijn 1989; Lee 1998; Leow 1998; VanPatten and Oikkenon 1996; Williams 1999). Implicit and explicit learning The discussion in the SLA literature on the question of how L2 grammatical knowledge is acquired has not only been in¯uenced by the issue of attention and noticing but also by the related distinction between implicit and explicit learning: Implicit learning is acquisition of knowledge about the underlying structure of a complex stimulus environment by a process which takes place naturally, simply and without conscious operations. Explicit learning is a more conscious operation where the individual makes and tests hypotheses in a search for structure. Knowledge attainment can thus take place implicitly (a nonconscious and automatic abstraction of the structural nature of the material arrived at from experience of instances), explicitly through selective learning (the learner searching for information and building then testing hypotheses), or, because we can communicate using language, explicitly via given rules (assimilation of a rule following explicit instruction) (N. Ellis 1994a: 1±2). Schmidt (1994b) argues that attention to input is necessary for explicit learning and may be both necessary and sucient for implicit learning. According to N. Ellis (1994a: 3±4), many issues concerning implicit and BATIA LAUFER and JAN HULSTIJN 5 explicit learning are as yet unresolved. What aspects of grammar and vocabulary can be learned implicitly? How modular and inaccessible is implicit learning? What are the various mechanisms of explicit learning? Are there sensitive periods for implicit language learning? What are the neural substrates of these processes? With regard to vocabulary learning, N. Ellis (1994b, 1994c) claims that the perceptual aspects of new words, i.e. acquiring their phonetic and phonological features, are learned implicitly as a result of frequent exposure. Similarly, the motor aspects of the articulation of word forms develop implicitly as a result of practice. However, the meaning of words is learned explicitly, requiring the conscious processing at the semantic and conceptual levels and paying attention to the form±meaning connections. Successful learners use sophisticated metacognitive learning strategies, such as inferring word meanings from context and semantic or imagery mediation, in this endeavour. Depth of processing The notion of implicit learning, as de®ned by Ellis, and the distinction between implicit and explicit learning, have their origins in connectionism, which emerged as a new perspective in cognitive psychology in the 1980s (see Broeder and Plunkett 1994, for an introduction). In the early 1970s, however, an important breakthrough occurred in the study of learning and memory, with the seminal work of Craik and Lockhart (1972), to which we will now turn. Their depth of processing hypothesis, and the notions and hypotheses of other scholars that grew out of it in subsequent years, can, from the current viewpoint of connectionism, be categorised as dealing with explicit learning. Craik and Lockhart argued that the chance that some piece of new information will be stored in long-term memory is not determined by the length of time that it is held in short-term memory but rather by the shallowness or depth with which it is initially processed. They further postulated several levels of processing depth. For instance, processing the meaning of a new lexical item takes place at a rather deep level whereas processing the phonological form takes place at a rather shallow level. Craik and Lockhart were initially successful in providing evidence that semantic processing of lexical items resulted in higher retention than phonological or orthographical processing. The levels of processing theory, however, was challenged, re®ned and modi®ed, and eventually even abolished, in the following years. Two of the problems were: (1) What exactly constitutes a `level' of processing, and (2) How do we know that one level is `deeper' than another? For instance, can non-semantic processing tasks still be meaningful activities? In other words, to be meaningful, an orienting task need not involve thinking about the meaning of a word; it could just as well involve thinking about its pronunciation or spelling. Craik and Tulving (1975) suggested that what is critical to retention is not 6 INCIDENTAL VOCABULARY ACQUISITION IN A SECOND LANGUAGE simply the presence or absence of semantic encoding, but the richness with which the material is encoded. A major obstacle facing all proposals resides in the diculty of providing an unambiguous, operationalisable de®nition of any notion proposed as a replacement for depth of processing, be it `encoding speci®city', `distinctiveness of encoding', `degree of elaboration', `cognitive eort', `degree of richness', etc. (Zechmeister and Nyberg 1982, ch. 12; Baddeley 1997). Yet, cognitive psychologists remained uni®ed in their view that `memory performance is determined far more by the nature of the processing activities engaged in by the learner than it is by the intention to learn per se' (Eysenck 1982: 203). Thus, researchers of knowledge representation, information encoding and retrieval, attention, and memory have not yet succeeded in providing adequate theoretical explanations of phenomena of human learning and memory in terms of quality (type) and quantity (duration and frequency) of information processing (Anderson 1995, ch. 6; Baddeley 1997, ch. 7). Yet they agree that processing new lexical information more elaborately (e.g. by paying careful attention to the word's pronunciation, orthography, grammatical category, meaning, and semantic relations to other words) will lead to higher retention than by processing new lexical information less elaborately (e.g. by paying attention to only one or two of these dimensions). MOTIVATIONAL ASPECTS OF L2 LEARNING IN RELATION TO COGNITION Our discussion of learning and cognition in the previous section was restricted to the literature of cognition exclusively conceived of as information processing. Human beings, however, are, as Gray (1999) observes, not just information-processing devices but they also possess motives and emotions, and they are integrated in a socio-cultural environment. Motivation, emotion, and socio-cultural factors may aect the way in which humans process information. Thus, cognition, as the `ability to acquire, organise, remember, and use knowledge to guide behavior' (Gray 1999: 22), can be studied not only in a narrow sense, as in most of the literature on implicit and explicit memory and learning, but also in a broader sense, as in¯uenced by motivations, attitudes, and social and cultural environments. (For an attempt to develop an integrated view of aect and information processing in the domain of SLA, see Schumann 1994, and Young and Perkins 1995.) The acquisition of a second language normally requires the learning of many thousands of words, and most L2 learners, being just `human', may approach this heavy learning load with a great deal of apprehension. Therefore, we decided to include at least one aspect of motivation, namely `need' in our construct of task-induced involvement load. In this section, we brie¯y review the relevant SLA literature. BATIA LAUFER and JAN HULSTIJN 7 Motivation Since the ground breaking work of Gardner and Lambert (1972), the literature on L2 learning motivation distinguishes two types of motivation, in¯uenced by integrative and instrumental orientations (reviews are given by Crookes and Schmidt 1991; R. Ellis 1994: 508±517; Skehan 1989, ch. 4). Integrative orientation involves an interest in L2 learning because of an interest in the people that speak the L2 and their culture, while an instrumental orientation concerns the practical value and advantage of L2 learning. Whereas orientation refers to the underlying reasons of L2 learning, motivation refers to the directed eort L2 learners make. Both integrative and instrumental motivation have been shown to be strongly related to L2 achievement. The socio-educational model of Gardner (1985) explains, at a general level, how motivations (as well as self-con®dence and attitudes) are aected by the socio-educational environment. However, as Crookes and Schmidt (1991) observe, it does not specify how various educational settings and instructional tasks may aect L2 learning motivation and how motivation might in¯uence information processing by promoting learners' attention. Crookes and Schmidt therefore present an agenda for research on the causal relationship between motivation and information processing in SLA. Since the appearance of the Crookes and Schmidt paper we have found no such empirical studies, at least no studies which investigated experimentally how motivation could be fostered or directed to induce L2 grammar or vocabulary learning. Even Skehan (1998) and (Robinson 2000) summing up the many factors contributing to task eectiveness, do not explore the question of how tasks might aect learners' motivation or need to pay attention to the L2 input. Somewhat closer to the possible relationship between tasks and motivation or need comes DoÈrnyei (1994). In an attempt to gear motivation research speci®cally to L2 learning in classroom settings, DoÈrnyei proposed a threelevel conceptualisation of L2 motivation. At the language level, motivation refers to orientations toward the language, the people that speak it, and their culture. At the learner level, motivation is concerned with the need for achievement (see below) and self-con®dence. At the learning situation level, motivation is considered as aected by (1) the syllabus and learning materials, (2) teachers' attitudes and behaviour, and (3) cohesion and goal-orientedness of the learners group. Although DoÈrnyei explicitly acknowledges the importance of the perceived interest, relevance, and satisfaction with the syllabus and learning materials, he does not provide a classi®cation of learning tasks in terms of their potential to aect learners' need or motivation to pay attention to the L2 input. Most studies of motivation (and other socio-psychological variables) adopt a correlational approach, measuring motivation by means of self-report questionnaires. There are almost no studies adopting a causal approach by trying to experimentally manipulate learners' motivation. In an exceptional 8 INCIDENTAL VOCABULARY ACQUISITION IN A SECOND LANGUAGE study, Gardner and MacIntyre (1991) compared vocabulary recall among two groups of psychology students who were given a list of 26 English±French word pairs. Students were native speakers of English in the Canadian province of Ontario; they were not students of French. One group was rewarded with $10 if they succeeded in learning 24 of the 26 words. Students in the other group were just told to do their best with memorising the words. The results showed that the ®nancially rewarded group performed signi®cantly better than the control group. Thus, this study provided some evidence that L2 vocabulary learning can be promoted by incentives. The incentive provided in this study, however, was extrinsic since it stemmed from the condition under which the learning task had to be performed and not from the task itself, or from the materials which were used to perform it. In a similar vein, Crookes and Schmidt (1991) refer to a study of cued recall of word list items (Eysenck and Eysenck 1980) in which an interaction was obtained between (1) absence or presence of monetary reward and (2) the strength of connections between the words and their corresponding retrieval cues. High incentive improved recall to weak retrieval cues but had no eect in the case of strong retrieval cues. This result suggests that the learning and retention of dicult words will bene®t more than the learning of easy words from need and motivation, whether they are induced by externally imposed incentives or by intrinsic drives. To our knowledge, no one has yet submitted this suggestion to an empirical test. Need In the SLA literature, we have come across the term `need', in only three places (Crookes and Schmidt 1991; Oxford and Shearin 1994, and Skehan 1989). Crookes and Schmidt (1991) mention the construct of need as part of Keller's (1983) education-oriented theory of motivation. Keller distinguishes many components of motivation, one of which is called instrumental needs. Instrumental needs are met when the content of a lesson or course matches what students believe they need to learn. Keller observes that humans have needs for achievement, for aliation, and for power. In an exploration of theories of motivation, relevant to L2 learning, Oxford and Shearin (1994) mention two need theories, basing themselves on Landy (1985), who claims that need is primarily a creator of tension. The ®rst one is known as Maslow's hierarchy of needs, claiming that people regress from their lower-order needs, such as self-actualisation, when their higher-order needs, such as the need for food and sleep, are not met. The second theory, (proposed by McClelland et al. 1953 and mentioned by Skehan 1989 as well), is based on the need for achievement, induced by fear of failure. However, to our knowledge, none of the need theories mentioned give a detailed account of how learning tasks could be classi®ed in terms of the degree of need they may evoke in the learner. BATIA LAUFER and JAN HULSTIJN 9 Summary From the literature reviewed in the preceding sections, we draw the following conclusions: 1 Attention, with noticing as its subjective correlate, appears to play a crucial role in both implicit and explicit language learning. 2 Whether grammatical knowledge can, cannot, or must be attained in an implicit or explicit way, is still an unresolved issue, complicated by dierent views on how various domains of grammar (abstract principles of the grammar's core, or less abstract regularities and irregularities of its periphery), are represented in the mind (as mental rules, or as a collection of items associated with each other in a neural network). 3 Input and output modules of the lexicon, responsible for perceiving and articulating words, appear to be learned implicitly, whereas word meanings appear to be learned explicitly. Elaborative attention to a word's formal and semantic features is conducive to its retention, but the literature does not specify how `elaboration' is aected by tasks. 4 Motivation for learning an L2 is aected by the sociocultural as well as by the educational environment re¯ected in learners' perceived interest, relevance of the syllabus and learning materials and satisfaction with them. Although the importance of the educational setting is acknowledged, no speci®c suggestions have been made about the eect the various educational settings and instructional tasks may have on L2 learning motivation and about the eect motivation might have on information processing by promoting learners' attention. 5 Two studies appear to provide evidence that external incentives, in the form of ®nancial reward, increase performance in learning a list of vocabulary items. The results of one of these studies suggest that the learning of dicult words may bene®t more from the provision of incentives than the learning of easy words. 6 There is at least one theory which explicitly subsumes need under motivation. Need creates tension. We understand this assertion to mean that a mild degree of tension may positively aect information processing, and therefore may indirectly aect learning. 7 Instrumental need is ful®lled when the content of a lesson or course matches what students believe they need to learn. Again, as in the case of motivation, no speci®c proposals have been made for how instructional tasks might foster instrumental need. 8 In summary, the most important conclusion to be drawn, in the context of our objective to stimulate theory and research on L2 vocabulary learning, is that no attempts were found in the literature to operationalise general constructs such as noticing, elaboration, motivation, or need, at the micro level of learning tasks. The construct of task-induced involvement load, which we will propose, is meant to be a step in this direction. 10 INCIDENTAL VOCABULARY ACQUISITION IN A SECOND LANGUAGE INCIDENTAL LEARNING Almost all of the many memory studies conducted in the tradition of Craik and Lockhart (1972) and Craik and Tulving (1975), adopted a so-called incidental learning design. In experiments investigating incidental vocabulary learning, learners are typically required to perform a task involving the processing of some information without being told in advance that they will be tested afterwards on their recall of that information. In contrast, participants in an intentional learning situation are told in advance that their recall will be tested afterwards. Incidental learning conditions allow researchers to investigate the eect of the particular kind of information processing they are interested in. One method is to expose subjects to the relevant material without instruction to learn (Type I design). This generally means that subjects must perform some sort of orienting task that leads them to experience the material to be tested but does not lead them to expect a later retention test. For example, subjects are given a list of words and asked to correct any spelling errors. Afterwards they are tested on the recall of all the words in the list. Another technique of investigating incidental learning is to ask subjects to learn something, but not the information targeted for subsequent testing (Type II design). For example, we give subjects a text to read and tell them they will be asked to recall the contents of the text. However, what the subjects are not told in advance, is that the text contains some unfamiliar words and that they will be tested afterwards on their recall of these words (see Hulstijn, in press, for an extensive treatment of incidental and intentional learning). The use of the terms incidental and intentional learning in the psychological literature goes back to the beginning of the twentieth century and has been used in experimental psychology for a long time. Hundreds of experiments on incidental and intentional learning have been conducted. Classical readings are Ebbinghaus (1964), Postman (1964), McLaughlin (1965) and Eysenck (1982). In operational terms, incidental and intentional learning can be distinguished simply in terms of prelearning instructions that either do, or do not, forewarn subjects about the existence of a subsequent retention test (Eysenck 1982: 198). Apart from the strictly methodological meaning of incidental learning as it is used in the experimental literature, the term incidental vocabulary learning has also been given a more general, educational meaning, referring to the learning without an intent to learn, or as the learning of one thing, e.g. vocabulary, when the learner's primary objective is to do something else, e.g. to communicate (Schmidt 1994a). Thus, in this more general de®nition, no mention is being made of the presence or absence of a forewarning of an upcoming retention test after the information-processing task. It is in this latter meaning, that incidental learning has become known in the ®eld of second and foreign language pedagogy, the most frequently quoted example being vocabulary learning as the by-product of reading (Krashen 1989). It should perhaps be pointed out that the notions of incidental and BATIA LAUFER and JAN HULSTIJN 11 intentional learning should not be confused with the notions of implicit and explicit learning or memory, as discussed in the previous section. Although implicit learning can be incidental only (i.e. without learners' awareness of an upcoming retention test, or without learners' deliberate decision to commit information to memory), explicit learning can occur both intentionally and incidentally. The relevance of the above distinctions to L2 vocabulary learning is not dicult to see. Since linking word form to word meaning is an explicit learning activity requiring attention on the part of the learner, vocabulary can therefore be learnt intentionally as well as incidentally. With regard to the empirical study of intentional vocabulary learning, it is hard to ®nd out which factors are responsible for vocabulary retention as researchers have no control over what people do when they decide to commit words to memory. A researcher or a teacher may, for example, suggest the use of the key word method, yet the learner will choose another memorisation strategy with which s/he may feel more comfortable. Incidental learning, on the other hand, can be manipulated and therefore empirically investigated. Teachers and researchers have control over the tasks which they assign in the belief that they are conducive to vocabulary learning. Controlled experiments, aiming to contribute to pedagogy and to the understanding of how words are acquired, will therefore usually adopt the incidental design. WHAT AFFECTS INCIDENTAL VOCABULARY LEARNING? EMPIRICAL EVIDENCE According to Hulstijn (1992), when learners were asked to infer the meaning of words from context by choosing the correct meaning from multiple choice options, subsequent retention of these words was better than when they were provided with a synonym of the words during a reading task. Luppescu and Day (1993), and Knight (1994) found that students who read a text and looked up unknown words in the dictionary remembered them better than students who read the text without a dictionary. We do not know whether in the latter case learners were trying to infer the meaning of unknown words, or were simply ignoring them. Hulstijn et al. (1996) found that the relatively few words that were looked up in the dictionary during a reading task yielded much higher retention scores on a subsequent test than the same words in the marginal gloss condition. In Paribakht and Wesche (1997), words that were practised in a series of exercises were retained better than words inferred from context. In Newton's (1995) study, items that were negotiated for meaning (by means of requests for clari®cations, or con®rmation checks) were better remembered than non-negotiated items, even by learners who were not using the words but simply observing the negotiation. Similarly, in R. Ellis (1994), interactionally modi®ed input, i.e. input that included clari®cations, resulted in more words that were learnt than pre-modi®ed input (input prepared on the basis of prior student interaction before the experimental task). In the latter case, however, more words were acquired per minute. Several studies 12 INCIDENTAL VOCABULARY ACQUISITION IN A SECOND LANGUAGE point to the value of output in speaking tasks for retention of new vocabulary. In Ellis and He (1999), interactionally modi®ed output fared better than interactionally modi®ed input. In a story retelling task used by Joe (1995, 1998), items used in original contexts were remembered better than items used in non-original contexts. The only study which examined the eect of writing on the retention of new vocabulary is by Hulstijn and Trompetter (1998). They found that looking up the words in an L1±L2 dictionary and incorporating them in a composition was more eective than looking up the words in an L2±L1 dictionary for comprehension purposes. The study by Cho and Krashen (1994) is often cited as evidence for vocabulary acquisition through reading. Yet it is interesting to look closely at what the four subjects in the study were doing and how much vocabulary each of them acquired. One of them did not use a dictionary at all and she acquired seven words from a book. The second subject used the dictionary initially only and abandoned it at a later stage. She acquired eight words. The other two subjects used the dictionary consistently and even wrote the words with example sentences in a booklet (though they were not trying to memorise these words intentionally). These subjects acquired 17 and 34 words per book. Hence, the study shows that dictionary use, a self-imposed task of two of the subjects, resulted in better vocabulary learning than reading only. The Table 1 summarises the studies mentioned above. At ®rst glance, there seems to be no connection among all the studies surveyed above. The tasks in some studies are communicative, in others they are not; in some studies, output is required of students, in others, the understanding of input; some studies use spoken language, others written language; some studies use paper and pen; others use computers. And yet, in each study, one task is superior to the other in terms of incidental vocabulary learning. In explaining this dierence, most authors suggest that the superior task required a deeper level of processing of the new words than the other task. Additional terms that have been used in connection with good retention induced by tasks are: greater depth of processing; better, more intense quality of information processing; degree of elaboration; quality of attention; richness of encoding. These explanations fall under the conclusion presented in the earlier review section that retention of information depends on the nature of the information processing. It should be noted that this explanation is usually a post-hoc explanation of the results. This is not surprising since the concepts of deep processing or elaboration defy simple formalisation and operationalisation. It is not dicult to decide that a totally meaning-oriented task requires deeper word processing than a totally form-oriented task, e.g. locate all words that end in a letter `e', or classify words by their part of speech. Yet in a normal language learning situation, teachers do not assign vocabulary tasks which do not include word meaning. Hence it is hard to decide in advance whether one instructional task requires deeper processing than another. Let us take, for example, three simple tasks learners can do with the word `skinny': (1) looking up its BATIA LAUFER and JAN HULSTIJN 13 Table 1: Task eect on incidental vocabulary learning The more eective task The less eective task Reference Meaning selected from several options Meaning looked up in a dictionary Meaning explained by synonym Reading with/without guessing Hulstijn 1992 Meaning looked up in a dictionary Reading and a series of vocabulary exercises Meaning negotiated Negotiated input Used in original sentences (oral task) Interactionally modi®ed output Used in a composition (L1±L2 look-up) Meaning provided in a marginal gloss Reading only (and inferring meaning) Meaning not negotiated Premodi®ed input Used in non-original sentences Interactionally modi®ed input Encountered in a reading task (L2±L1 look-up) Reading only, words not looked up Reading, words looked up in a dictionary (selfimposed) Knight 1994; Luppescu and Day 1993 Hulstijn et al. 1996 Paribakht and Wesche 1997 Newton 1995 R. Ellis et al. 1994 Joe 1995, 1998 R. Ellis and He 1999 Hulstijn and Trompetter, 1998 Cho and Krashen 1994 meaning in a dictionary and writing a sentence with the word; (2) looking up its meaning and explaining the dierence between `skinny', `thin', and `slim'; and (3) receiving a sentence with the word and trying to infer its meaning from four alternatives presented by the teacher. There are no de®nite criteria which would help us grade the three tasks in terms of the depth of processing they require. Hence, if our concern is eective learning and teaching, we do not know which task is more eective than which. And yet research on task eectiveness would require the identi®cation of criteria which could be observed, manipulated, and measured. TASK-INDUCED INVOLVEMENT On the basis of the analysis of tasks surveyed earlier and on the basis of our conclusion drawn from the literature reviewed, we propose to identify the components of incidental tasks which we believe are conducive to the kind of elaborate processing crucial for learning. This proposal should be conceived as a ®rst attempt to stimulate researchers as well as practitioners to 14 INCIDENTAL VOCABULARY ACQUISITION IN A SECOND LANGUAGE operationalise the general labels of `attention' and `elaboration' into concrete task-speci®c constructs. For now, three such components will be proposed which, taken together, constitute the construct of involvement. Involvement Our ®rst assumption about determining factors in vocabulary retention is as follows: Assumption One: Retention of words when processed incidentally, is conditional upon the following factors in a task: need, search, and evaluation. Taken together, these three factors combine into what will be referred to as involvement. Involvement is perceived as a motivational-cognitive construct which can explain and predict learners' success in the retention of hitherto unfamiliar words. We use the label cognitive in its narrow sense, i.e. referring to information processing only, with the exclusion of aective aspects of cognition, as explained in the preceding review. The need component is the motivational, non-cognitive dimension of involvement. It is concerned with the need to achieve. We interpret this notion not in its negative sense, based on fear of failure, but in its positive sense, based on a drive to comply with the task requirements, whereby the task requirements can be either externally imposed or self-imposed. If, for example, the learner is reading a text and an unknown word is absolutely necessary for comprehension, s/he will experience the need to understand it. Or, the need will arise during a writing or speaking task when the L2 learner wants to refer to a certain concept or object but the L2 word expressing it is unfamiliar. We propose to distinguish between `moderate' and `strong' need. Need is moderate when it is imposed by an external agent, e. g. the need to use a word in a sentence which the teacher has asked the learner to produce. Need is strong when imposed on the learner by him- or herself. A case in point is a decision to express a concept without knowing the appropriate word for it. In the case of need, moderate and strong subsume dierent degrees of drive. Search and evaluation are the two cognitive (information processing) dimensions of involvement, contingent upon noticing and deliberately allocating attention to the form±meaning relationship (Schmidt 1994a, 2000). Search is the attempt to ®nd the meaning of an unknown L2 word or trying to ®nd the L2 word form expressing a concept (e.g. trying to ®nd the L2 translation of an L1 word) by consulting a dictionary or another authority (e.g. a teacher). Evaluation entails a comparison of a given word with other words, a speci®c meaning of a word with its other meanings, or combining the word with other words in order to assess whether a word (i.e. a form±meaning pair) does or does not ®t its context. If, for example, during a reading task, a word that is BATIA LAUFER and JAN HULSTIJN 15 looked up is a homonym, a decision has to be made about its meaning by comparing all its meanings against the speci®c context and choosing the one that ®ts best. Another example is an L2 writing task in which an L1 word is looked up in a dictionary and three L2 alternatives are presented. The translations have to be evaluated against each other and the most suitable one has to be chosen for the speci®c meaning the L2 writer is trying to convey. But unlike in the preceding example, the evaluation in the writing task will involve additional syntagmatic decisions about the precise collocations of the word which the learner is trying to use. Evaluation, as illustrated by the two examples above, implies some kind of selective decision based on a criterion of semantic and formal appropriateness (®t) of the word and its context. If the evaluation entails recognising dierences between words (as in a ®ll-in task with words provided), or dierences between several senses of a word in a given context, we will refer to this kind of evaluation as `moderate'. If, on the other hand, evaluation requires making a decision about additional words which will combine with the new word in an original sentence or text, we will refer to it as `strong' evaluation. Involvement load A real-life communicative situation, or a teacher-designed learning task can induce any one, two, or all three of the components of involvement for each word: need, search, and evaluation. A reading comprehension task which requires the learner to look up the meaning of a homonym in a dictionary, illustrates need (since knowing the word's meaning is necessary for the successful completion of the comprehension task), search (since the meaning of the word is looked up), and evaluation (since dierent meanings of the word have to be compared and checked against the context before one is selected). If, however, the same task is simpli®ed for the learner by teacher's glosses for unknown words in the text margin, search and evaluation are no longer required. In the latter example, the task induces a weaker involvement in the word as only the need component is at work. The task of the former example, however, requiring need, search, and evaluation, induces a stronger involvement. Thus we may say that tasks dier in the involvement load they generate. In conclusion, involvement load is de®ned here as the combination of the presence or absence of the involvement factors Need, Search, and Evaluation. The variability in involvement load that can be experienced for dierent words leads us to formulate our second assumption. Assumption Two: Other factors being equal, words which are processed with higher involvement load will be retained better than words which are processed with lower involvement load [Note 1]. 16 INCIDENTAL VOCABULARY ACQUISITION IN A SECOND LANGUAGE Task-induced involvement load Before exploring the notion of involvement load in this subsection, we would like to point out that we adopt the general de®nition of task as provided by Richards et al. (1985: 289), as `an activity or action which is carried out as the result of processing or understanding language (i.e. as a response)'. In the socalled task-based approach, task is given a more speci®c meaning as `an activity in which: meaning is primary; there is some communication problem to solve; there is some sort of relationship to comparable real-world activities; task completion has some priority; the assessment of the task is in terms of outcome' (Skehan 1998: 95). We subscribe to the pedagogical aims of the task-based approach and thus adhere to Skehan's urge `to develop pedagogic interventions where learners focus on form naturally, rather than arti®cially' (Skehan 1998: 40). However, in the context of our aim to stimulate theory and empirical research (as opposed to sound pedagogical practice), it suces to adopt the more general de®nition even though that de®nition encompasses arti®cial noncommunicative tasks, such as ®lling in gaps or writing isolated and unconnected sentences with given words. Of course, in applying the notion of involvement to the language classroom, one would try to follow Skehan's principle. The examples in the previous subsection, show that, in a natural communicative task, dierent words can induce dierent involvement loads. In a teaching context, however, or for research purposes, tasks can be designed in such a way that the involvement load is (almost) identical for all the words targeted for teaching or research. We will refer to this involvement load as task-induced involvement load and illustrate it by analysing some learning tasks, widely practised in educational settings, in terms of need, search, and evaluation of newly met words (see Table 2). Let us ®rst consider several reading tasks. A reading comprehension task where unknown words are glossed for the student, but the comprehension questions can be answered without reference to these words (1 in Table 2) does not induce any need to focus on the glossed words (since they are irrelevant to the task), nor any search for their meaning (since they are glossed), nor any evaluation. A reading comprehension task with glossed words that are relevant to answering the questions (2 in Table 2) will induce a moderate need to look at the glosses (moderate because it is imposed by the task), but it will induce neither search nor evaluation. The same task with glosses removed (3 in Table 2), will not only induce need but also search (provided that the student has deemed the unknown words as relevant enough to look up). The presence or absence of evaluation may vary with type of word and context. If an unknown word has only one meaning and if the context allows a straightforward, literal interpretation of it, no decision has to be made about its contextual meaning. If, on the other hand, the word has several meanings, the reader has to select the meaning which makes sense in the context, a decision demanding moderate evaluationÐmoderate since the learner is not required to produce original language. BATIA LAUFER and JAN HULSTIJN 17 Let us now imagine the same text, but the target words have been deleted from it. These words are listed at the bottom of the text with their translations or explanations and the task requires the learner to ®ll the text gaps with the correct words from the list (the task can be made more complex by adding to the list words that do not ®t the text at all) and to answer the comprehension questions (4 in Table 2). The ®ll-in task induces a moderate need, no search (the words are explained) and a moderate evaluation, since all the words in the list have to be evaluated against each other and the context of the gaps. The next three examples are of writing tasks. In the ®fth task the learner is asked to write original sentences with some new words. These words are translated or explained by the teacher. The task induces a moderate need, no search, and strong evaluation because the new words are evaluated against suitable collocations in a learner-generated context. Now suppose the learner is required to write a composition (as opposed to single sentences) and incorporate some L2 target words; the teacher has not provided these words in their L2 form, but by their L1 equivalent (6 in Table 2). The task will induce a moderate need and search since the L2 word forms have to be looked up, and again a strong evaluation as the words are used in learner-generated contexts. Finally, consider a case of a composition where the learner wants to use concepts for which s/he possesses no L2 form. S/he then decides to look up these L1 concepts for their L2 equivalence (in an L1±L2 dictionary) and use them in the composition (7 in Table 2). This task induces a strong need (selfimposed), search, and a strong evaluation. The above analysis is summed up in Table 2. A minus (±) indicates an absence of an involvement factor, a plus (+) indicates that the factor is present in its moderate version, a double plus (++) marks the strong version of an involvement factor. Table 2 clearly shows how dierent tasks dier in the involvement load they induce from the learner. This variability in task-induced involvement load, together with Assumption Two, lead us to formulate our third assumption. Assumption Three: Other factors being equal, teacher/researcherdesigned tasks with a higher involvement load will be more eective for vocabulary retention than tasks with a lower involvement load. In summary, we propose a motivational-cognitive construct of involvement, consisting of three basic components: need, search, and evaluation. Each of these three factors can be absent or present when processing a word in a natural or arti®cially designed task. The combination of factors with their degrees of prominence constitutes involvement load. Our basic assumption regarding vocabulary retention is that retention of hitherto unfamiliar words is conditional, in general, upon the degree of involvement in processing these words. The concept of involvement can be operationalised by devising tasks with various degrees of need, search, and evaluation and can therefore be submitted to empirical investigation. 18 INCIDENTAL VOCABULARY ACQUISITION IN A SECOND LANGUAGE Table 2: Task-induced involvement load Task Status of target words Need Search Evaluation 1. Reading and comprehension questions 2. Reading and comprehension questions 3. Reading and comprehension questions Glossed in text but irrelevant to task ± ± ± Glossed in text and relevant to task + ± ± Not glossed but relevant to task + + 4. Reading and comprehension questions and ®lling gaps 5. Writing original sentences 6. Writing a composition Relevant to reading + comprehension. Listed with glosses at the end of text Listed with glosses + ± ±/+ (depending on word and context) + ± ++ Concepts selected + by the teacher (and provided in L1). The L2 learner± writer must look up the L2 form Concepts selected ++ (and looked up) by L2 learner±writer + ++ + ++ 7. Writing a composition THE INVOLVEMENT LOAD HYPOTHESIS: EMPIRICAL AND THEORETICAL PERSPECTIVES The Involvement Load Hypothesis: empirical support Let us revisit the Task Table (Table 1) presented earlier, comparing each pair of tasks in terms of their involvement load. The table is reproduced as Table 3, this time showing which involvement component is present in one task of the pair and absent in the other. Three examples will be singled out for detailed illustration of the dierences in the involvement load of the tasks. Hulstijn (1992) showed that when meanings of words had to be inferred they were retained better than words with given meanings. If we compare the BATIA LAUFER and JAN HULSTIJN 19 Table 3: Previous research re-visited The more eective task The less eective task Reference Meaning selected from several options +evaluation Meaning looked up in a dictionary +search Meaning looked up in a dictionary +search Meaning negotiated ++ need, +search Negotiated input +search Used in original sentences ++evaluation Used in a composition (L1±L2 look up) ++evaluation Interactionally modi®ed output ++evaluation Reading and a series of vocabulary exercises +evaluation/++evaluation Reading, words looked up in a dictionary +search Meaning explained by synonym Hulstijn 1992 Reading with/without guessing +/±search Meaning provided in a marginal gloss Meaning not negotiated Knight 1994; Luppescu and Day 1993 Hulstijn et al. 1996 Newton 1995 Premodi®ed input R. Ellis et al. 1994 Joe 1995, 1998 Used in non-original sentences Encountered in a reading task (L2±L1 look up) ±/+evaluation Interactionally modi®ed input Reading only (and inferring meaning) ±/+evaluation Reading only, words not looked up Hulstijn and Trompetter 1998 R. Ellis and He 1999 Paribakht and Wesche 1997 Cho and Krashen 1994 two tasks in terms of involvement load, we can see that the dierence lies in the absence of evaluation in the synonym-condition and presence of evaluation in the multiple-choice condition. Learners had to evaluate all the alternative meanings against the text context. (In both conditions there was a moderate need, induced by the researcher, and no search). Newton (1995) found that words which were negotiated for meaning in an interactive task were retained better than words that were not negotiated. Put dierently, the choice to negotiate a word implies a need, induced by the learner, and also a search for meaning. (Search for meaning does not have to be in a dictionary only. The learner can search the text context, ask a teacher, or peers.) When unknown words are not negotiated, it means the learner has no need for them and therefore performs no search. 20 INCIDENTAL VOCABULARY ACQUISITION IN A SECOND LANGUAGE Joe (1995) shows that words with a `high degree of generation' are better retained than words with a low degree of generation, or no generation at all. What this means is that when words are used in a learner-generated, original context, they are better retained than if they are used in a non-original context (for example, memorised from text), or not used at all. The dierence probably lies in all three factors of involvement, but a fair comparison cannot be made since memorisation belongs to the realm of intentional learning whereas our construct of involvement applies to incidental learning. Thus, the results of the study conducted by Newton and, perhaps in part, the results of Joe's study can also be explained in terms of involvement. Words which were retained better underwent a higher involvement load than words which were retained less well. The Involvement Load Hypothesis: a theoretical perspective As mentioned in the introductory section, psychologists have associated better learning with depth of processing, or degree of elaboration, or quality of attention to information. Our construct of involvement decomposes the concept of processing into two cognitive components (search and evaluation) and adds a motivational component (need). This proposal should be conceived of as a ®rst attempt to stimulate researchers as well as practitioners to operationalise traditional general labels such as noticing, attention, elaboration, and motivation, into task-speci®c components. Thus, although involvement will vary with words, involvement can also be in¯uenced by task factors. It is on the task factors that we direct our focus. All three factors can be manipulated separately and in dierent combinations by researchers or teachers as shown in Table 2. As a research paradigm, therefore, our proposal oers multiple possibilities to explore the relationship between retention and various aspects of deep processing. This can be done by designing experimental tasks with varying involvement loads. How does the construct of involvement load relate to the Input Hypothesis (Krashen 1985) and the Output Hypothesis in SLA (Swain 1985, 1996)? The Involvement Load Hypothesis does not predict that any output task will lead to better results than any input task. It predicts that higher involvement in a word induced by the task (natural or arti®cial) will result in better retention regardless of whether it is an input or an output task. To illustrate this point, let us consider three tasks: one input and two output tasks. The input task is to read a text for comprehension. During the reading, the learner decides to look up certain words in a dictionary. Since it was the learner's decision, the need is characterised as strong. Looking up the meaning of a word implies a search. Let us assume the looked-up words have one unequivocal meaning and the context does not lead to interpretation diculties: hence there is no evaluation in the task. The involvement load of the task is therefore ++need, +search, ±evaluation. Now consider an output task: an exercise where words have to be ®lled in BATIA LAUFER and JAN HULSTIJN 21 into sentence blanks. The words to be ®lled in are written out in a list with their translations or explanations. Since the use of words is imposed by the teacher, need is moderate. There is no search as the words are glossed. In order to ®ll in the correct word in each blank, the candidate words provided by the teacher have to be evaluated against each other in the context of each blank. Therefore the task requires a moderate amount of evaluation. The involvement load of this output task is +need, ±search, +evaluation. Finally, consider another output task: writing original sentences with words which are provided with their translations or explanations. The need and search of this task are the same as in the previous output task. Yet the amount of evaluation is higher as the words are used in an original context. The involvement load of this task is + need, ±search, ++evaluation. The Involvement Load Hypothesis predicts that, among the ®rst two tasks, it is the input task, reading with look-ups, that will yield better retention since it is more involving than the ®ll-in output task. It also predicts that the input task and the second output task, sentence writing, will be equally bene®cial for retention since the two are identical in their involvement load. Similarly, the model predicts that task eect does not depend on the mode as such, i.e. whether the task is aural, oral, or visual. What matters is the motivationalcognitive dimensions of the task, i.e. its involvement load. The above predictions can be tested, as will be suggested in the next section. SUGGESTIONS FOR FURTHER RESEARCH Further investigation of the involvement load eect Our basic contention is that the eectiveness of a task is determined by the involvement load it induces. Research should be conducted to test this contention. Tasks with dierent involvement loads could be compared with regard to their eect on incidental vocabulary learning. A particularly interesting comparison would involve conditions where the input and output tasks have identical involvement loads. If involvement load is the determining factor in task eectiveness, irrespective of whether the task is input or output oriented, the two conditions should yield similar retention results. Establishing the relative importance of need, search, and evaluation So far the amount of the involvement load has been conceived of as the sum of the plusses (of need, search, and evaluation). For example, a task consisting of +need, +search, ±evaluation has the same involvement load as a task consisting of +need, ±search, +evaluation. Yet all three factors may not be equally important for vocabulary learning. Earlier we suggested that the weight (impact on incidental learning) of search might be lower than that of need and evaluation. Empirical research should compare tasks with the same 22 INCIDENTAL VOCABULARY ACQUISITION IN A SECOND LANGUAGE number of components (two), but a dierent distribution of the components involved. Comparing the quality and quantity of exposure to words A crucial question in understanding vocabulary learning is whether retention depends on what one does with the word rather than how often one meets it. In pedagogy, the question is whether task type is just as important, more so, or less so than the number of tasks in which a new word appears. Put dierently, we would like to ®nd out whether the quality of exposure to new vocabulary during `incidental' encounters can compensate for the relatively limited amount of exposure which is characteristic of learning a second language in a non-language speaking environment. Research could compare vocabulary retention along two dimensions: varying task involvement loads and varying the number of exposures to the investigated words. CONCLUDING REMARKS: A PLEA FOR THEORY BUILDING The generality of the constructs in the theoretical literature and the paucity of empirical research testing the noticing and elaboration hypotheses in the domain of L2 vocabulary learning led us to adopt `a bottom-up approach' and start our investigation at the task end of the issue. We examined a number of studies on incidental vocabulary learning and inferred from them, in an inductive fashion, three constructs: need, search, and evaluation. We are fully aware of the possible criticisms of such a bottom-up approach since it draws post hoc conclusions from existing instructional tasks rather than from results of controlled experiments of the kind psychologists conduct in laboratories. Yet this is not an unacceptable scholarly procedure. Advancement in scholarly inquiry, both in terms of theory building and in terms of providing empirical data, can proceed in a number of ways (Kuhn 1974). One way is to begin at the higher end of the hermeneutic cycle: developing theory, deducing hypotheses from it, testing them empirically, and applying the theory's constructs and theses to practice. Another way is to begin at the lower end of the hermeneutic cycle: looking at empirical data, trying to discern general patterns, and establishing links with existing theories or developing new theories. Whichever route is taken, full circle must be made eventually. Given the fact that the last decade has not shown much progress in applying cognitive notions to the domain of L2 vocabulary learning (in comparison to the domain of L2 grammar learning, where research on noticing, pushed output, recasts, and other types of feedback is thriving) we felt justi®ed in adopting the latter, `bottom-up' approach. As mentioned in the introduction, we hope that our Involvement Load Hypothesis will be a ®rst step in stimulating theoretical and empirical work and will be followed by other proposals of greater scope and depth. Greater depth could be re¯ected in more precise de®nitions of the involvement BATIA LAUFER and JAN HULSTIJN 23 components and a more thorough theoretical link between them and theories of information processing and aective components of cognition. Broader scope could take the form of adding new components to the three proposed here and, eventually, providing a theoretical underpinning for each of them. (Revised version received March 2000) ACKNOWLEDGEMENTS We are grateful to our colleagues for their helpful comments on an earlier version of this paper: Nanda Poulisse, Rob Schoonen, and Elisabeth van der Linden from the University of Amsterdam, Paul Meara from the University of Swansea, Paul Nation from the Victoria University of Wellington, and Norbert Schmitt from the University of Nottingham. 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