Characteristics of Optimal Input for Second Language Acquisition
This paper is an attempt to shed light on the notion of Second Language Acquisition (SLA) in general, and the characteristic features of optimal input that accelerate the process of L2 acquisition in particular. Here, reference is made to Krashen’s theory of SLA which emphasizes the role of comprehensible input as the most important factor for language acquisition (Krashen, 1982), and the features that characterize optimal input. The paper also explores other features that encourage and facilitate acquisition in order for it to occur at its highest possible levels.
acquisition, characteristics, optimal, input, hypothesis, comprehensible
Language acquisition occurs via two main mechanisms; the native language, first language acquisition (FLA) or a foreign language in addition to L1. In this case it is called second/foreign language acquisition (SLA). Both processes are achieved through different means, but the main focus in this paper is on the latter; SLA. Krashen (1981) thinks that speaking the foreign language promotes acquisition, and conversation in which the acquirer has some sort of control over the topic and in which the other participants exert an effort to make themselves understood provide valuable intake.
Krashen believes that the best activities for the classroom are those that are natural, interesting and comprehensible. He claims that if the teaching programme can provide these characteristics then the classroom may be the best place for L2 acquisition, up to the intermediate level. Similarly, Littlewood (1984, 59) considers “the ideal input for acquiring a second language is similar to the input received by the child, comprehensible, relevant to their immediate interests, not too complex, but not strictly graded either”. Krashen (1982) presents a set of requirements that should be met by any activity aiming at subconscious language acquisition. In this respect, he considers comprehensible input the most important factor for language acquisition, and he regards incomprehensible input as a factor that hinders L2 acquisition. According to him, this explains why educational T.V. programmes fail to teach foreign languages unless the acquirer speaks “a very closely related language”. These factors have led Krashen to define the good language teacher as “someone who can make input comprehensible to a non-native speaker, regardless of his or her level of competence in the target language” (ibid,64).
Krashen (1982) also strongly believes that the best input is so interesting, natural and relevant that the acquirer (the learner) may even “forget” that the message is encoded in a foreign language. In addition, optimal input is not grammatically structured. When we focus on grammatical considerations, there will be less genuinely interesting input. He maintains that optimal input must be in sufficient quantity. It seems clear to him, however, that much time should be devoted to supplying comprehensible input, and that would stimulate more rapid second language acquisition in that the acquirer can get more of the target language (Hasan, 208).
2. Language Acquisition
By language acquisition, we mean the process of learning and development of a person’s language (Fletcher, 1985). It is the process by which humans acquire the capacity to perceive and comprehend language, as well as to produce and use words and sentences in order to communicate. The learning of a native or first language (L1) is called first language acquisition (FLA), while the term second language acquisition (SLA) is used to refer to the learning of a second or foreign language (L2) (Mansoor, 2014: 137-138).
It is important to make a distinction between acquisition and learning. By acquisition, we mean the gradual development of ability in a language by using it naturally and subconsciously in communicative situations with those who know and speak the language. Learning, on the other hand, refers to a more conscious process of studying a language, usually in an institutional setting (through instruction). Thus, the first term refers to L1, while the second refers to L2 (ibid).
2.1 Second Language Acquisition
SLA is a term used to refer to the processes by which people develop proficiency in a second or foreign language. Historically, SLA began as an interdisciplinary field (Gass and Selinker, 2008: 1). However, the early beginning of this field goes back to Corder’s (1967) essay The Significance of Learners’ Errors, and Selinker’s (1972) article Interlanguage (VanPatten ; Benati, 2010: 2-5). In the 1970s the general trend in SLA was for research exploring the ideas of Corder and Selinker, and refuting behaviorist theories of language acquisition.
By the 1980s, the theories of Stephen Krashen had become the prominent paradigm in SLA. In his theory, known as the Input Hypothesis, Krashen suggested that language acquisition is basically achieved by what he called comprehensible input; language input that learners can understand. Krashen’s model was influential in the field of SLA and also had a large influence on language teaching, but it left some important processes in SLA unexplained. Research in the 1980s was characterized by the attempt to fill in these gaps. Some approaches included White’s descriptions of learner competence, and Pienemann’s use of speech processing models and lexical functional grammar to explain learner output (ibid).
The 1990s witnessed the introduction of sociocultural theory, an approach to explain second-language acquisition in terms of the social environment of the learner. In the 2000s research was split into two main camps of linguistic and psychological approaches. VanPatten and Benati do not see this state of affairs as changing in the near future, pointing to the support both areas of research have in the wider fields of linguistics and psychology, respectively (ibid, cited in wikipedia, 2018).
3. Krashen’s Theory of SLA
Krashen’s theory of second language acquisition consists of five main hypotheses (Krashen, 1982: 10-32). These include:
3.1 The Acquisition-Learning Hypothesis
The Acquisition-Learning distinction is the most fundamental of all the hypotheses in Krashen’s theory and the most widely known among linguists and language practitioners. According to Krashen there are two independent systems of second language performance: ‘the acquired system’ and ‘the learned system’. The ‘acquired system’ or ‘acquisition’ is the product of a subconscious process very similar to the process children undergo when they acquire their L1. It requires meaningful interaction in the target language, natural communication, in which speakers concentrate not on the form of their utterances, but on the communicative act.
The “learned system” or “learning” is the product of formal instruction and it comprises a conscious process which results in conscious knowledge about the language, for example knowledge of grammar rules. According to Krashen learning is less important than acquisition (ibid).
3.2 The Monitor Hypothesis
The Monitor Hypothesis explains the relationship between acquisition and learning and defines the influence of the latter on the former. The monitoring function is the practical result of the learned grammar. According to Krashen, the acquisition system is the utterance initiator, while the learning system performs the role of the ‘monitor’ or the ‘editor’. The monitor acts in a planning, editing and correcting function when three specific conditions are met: the second language learner has sufficient time at his/her disposal, he/she focuses on form or thinks about correctness, and he/she knows the rule.
It appears that the role of conscious learning is somewhat limited in second language performance. According to Krashen, the role of the monitor is or should be minor, being used only to correct deviations from normal speech and to give speech a more polished appearance. Krashen also suggests that there is individual variation among language learners with regard to monitor use. He distinguishes those learners that use the monitor all the time (over-users); those learners who have not learned or who prefer not to use their conscious knowledge (under-users); and those learners that use the monitor appropriately (optimal users) (ibid).
3.3 The Natural Order Hypothesis
The Natural Order Hypothesis is based on research findings (Dulay ; Burt, 1974; Fathman, 1975; Makino, 1980 cited in Krashen, 1982) which suggest that the acquisition of grammatical structures follows a natural order which is predictable. For a given language, some grammatical structures tend to be acquired early while others late. This order seemed to be independent of the learners’ age, L1 background and conditions of exposure. Although the agreement between individual acquirers was not always definitive in the studies, there were statistically significant similarities that reinforced the existence of a Natural Order of language acquisition. Krashen; however, points out that the implication of the natural order hypothesis is not that a language program syllabus should be based on the order found in the studies. In fact, he rejects grammatical sequencing when the goal is language acquisition.
3.4 The Input Hypothesis
The Input Hypothesis is Krashen’s attempt to explain how the learner acquires a second language and how second language acquisition takes place. He puts it in this way:” The important question is: How do we acquire language?”(Krashen, 1982: 20). The Input hypothesis is only concerned with acquisition, not learning. According to this hypothesis, the learner improves and progresses along the natural order when he/she receives second language input that is one step beyond his/her current stage of linguistic competence. For example, if a learner is at a stage ‘i’ (where i represents current competence), then acquisition takes place when he/she is exposed to ‘Comprehensible Input’ that belongs to level ‘i + 1’ (where I represents the next level) since not all of the learners can be at the same level of linguistic competence at the same time.
Krashen suggests that natural communicative input is the key to designing a syllabus, ensuring in this way that each learner will receive some ‘i + 1’ input that is appropriate for his/her current stage of linguistic competence (ibid).
3.5 The Affective Filter Hypothesis
According to Krashen there are a number of affective variables that play a facilitative, but non-causal role in second language acquisition. These variables include: motivation, self-confidence and anxiety (Krashen, 1981). Krashen claims that learners with high motivation, self-confidence, a good self-image and a low level of anxiety are better equipped for success in second language acquisition. Low motivation, low self-esteem and great anxiety can combine to raise the affective filter and form a mental block that prevents comprehensible input from being used for acquisition. In other words, when the filter is up it impedes language acquisition. On the other hand, positive affect is necessary, but not sufficient on its own, for acquisition to take place (www.sk.com).
4. The Role of Input
In normal conditions, infants are helped in their language acquisition by the typical behaviour of older children and adults in the home environment who provide language samples or input for the child. This input is usually a simplified speech style given by someone who spends a lot of time interacting with the child (like parents or caregivers). This speech which is addressed to young children by the adults or older children who are looking after them is called motherese or caregiver speech (Snow ; Ferguson, 1977; Richards, et al, 1993:45; Yule, 2010:171).
This kind of speech is also referred to as comprehensible input that can be understood by listeners although they do not understand all the words and structures in it. According to Krashen (1982, 62), giving learners this kind of input helps them acquire language naturally, rather than learn it consciously.
4.1 Characteristics of Optimal Input
Krashen (1982) defined that optimal input should be comprehensible, be interesting and/or relevant, not be grammatically sequenced and be in sufficient quantity. If the leaner can be exposed to input having these characteristic features, it is considered that acquisition is more likely to occur at its best possible levels.
Krashen (1982, 63) consider this as the most important input characteristic. To him, when the acquirer does not understand the message, there will be no acquisition. This means that incomprehensible input is merely noise which doesn’t help in the process of SLA. According to information processing theory concerning comprehension and production, if the learner cannot keep up with the rate of exposure and the input content is far beyond his linguistic competence, he/she will fail to comprehend and therefore, to acquire (Carroll,1990, cited in Wang, 2010). Therefore, the teacher must ensure that the material he/she chooses is not so demanding on the student. A “defining characteristic of a good teacher is someone who can make input comprehensible to a non-native speaker, regardless of his or her level of competence in the target language” (Krashen, 1982: 64). Krashen maintains that the main function of all teachers is to try to help make input comprehensible (both linguistically and non-linguistically); to do for the adult learner what the outside world cannot or will not do (ibid).
Linguistically, studies have shown that many things can be done to make the speech more comprehensible to less competent speakers. Hatch, 1979 (cited in Krashen, 1982: 64) has summarized the linguistic aspects of simplified input which appear to promote comprehension as follows:
1. Slower rate and clearer articulation, which helps acquirers to identify word
boundaries more easily, and allows more processing time.
2. More use of high frequency vocabulary, less slang, fewer idioms.
3. Syntactic simplification, shorter sentences.
Non-linguistically, providing extra-linguistic support in the form of realia (real objects) and pictures for beginning classes have proved to be helpful devices to encourage SLA. Good teachers also take advantage of the student’s knowledge of the world in helping comprehension by discussing topics that are familiar to the student. Discussing or reading about a topic that is totally unknown to the learner will make the message harder to understand, and consequently hinders acquisition.
Although some research results show that a large amount of exposure to L2 leads to proficiency, some had doubted whether it would help by sheer exposure without comprehension. This point of view was derived from the observation and study of the “Motherese” (Snow, 1977) in first language acquisition and was extended to second language acquisition theories.
Psychological findings (Carroll, 1990) have also provided evidence that only when the meaning of an utterance or a sentence is understood and processed, it can be stored in the long-term memory. Krashen (1978) argues that the learner’s brain functions like a filter of the information or input provided by the outside world. Only the part that is understandable can possibly pass through the filter and become intake of the leaner. Not only does the incomprehensible part fail to facilitate acquisition to occur, but it will also take too much effort on the part of the learner to filter it out. Therefore, the incomprehensible part of the input contributes little to learning, and hinders it by frustrating the learner.
Corder (1981) has also pointed out that simply presenting a certain linguistic form to a learner in the classroom does not necessarily qualify it for the status of input, since input is “what goes in”, not what is “available” for going in. Those language forms which cannot be processed by the learner can by no means become the intake of the learner, and cannot become the output of the learner. To look at this question from another angle, it is generally agreed that comprehension usually precedes production, and without comprehension learning will not occur.
4.1.2 Interesting and/or Relevant
Another characteristic of optimal input is that it should be interestingly relevant. The best input is so interesting, natural and relevant that the acquirer may even forget that the message is encoded in a foreign language. Providing an interesting and relevant input is not an easy task. It requires much consideration, attention and collaboration on the part of textbook writers, educators and teachers. As for the foreign class situation, it is very difficult to present and discuss topics of interest to a class of people whose goals, interests and backgrounds differ from the teacher’s and from each other’s (Krashen, 1982: 67). Added to this, relevance and interest have not been widely perceived as requirements for input, since so many materials (used in traditional ESL courses) have failed to cope with them.
Traditional teaching focusing on pattern practice drills and dialogues for memorization have failed to equip learners with interesting and relevant information and situations. Such exercises may be comprehensible, but they lack relevance and interest. It is not an easy task on the part of teachersto provide their ESL students with instances of interest and relevance. This is a joined effort on the part of textbook writers, educators and teachers who should work as a team to achieve this goal. A possible way of doing this lies in “English for academic purposes, introduction to university life, and even useful academic skills. ESL teachers often serve officially or unofficially as friends and counselors, and therefore provide a great deal of truly relevant input”(ibid, 68).
4.1.3 Sufficient in Quantity
The purpose of language teaching is to provide optimal samples of the language for the learner to profit from. However, if the quantity of input cannot be ensured, the input still cannot be said to be optimal. That is why Krashen (1982: 71) has claimed that optimal input should be in sufficient quantity. Actually the quantity of input is the main concern of optimal input hypothesis, since the big difference between foreign learning in the mother tongue environment and SLA in the target language environment lies in the amount of input that is available to the learner.
An important question to raise is “How much input? This is a crucial question whose answer depends on empirical findings. Krashen’s suggestion in this respect is what he calls extensive-intensive reading, that students profit more from reading for meaning, and reading great quantities of material. To him, students gain more from participating in conversations, many conversations, than from focused listening comprehension exercises (ibid, 73).
4.1.4 Not Grammatically Sequenced
With a grammatical focus, communication will always suffer, there will always be less genuinely interesting input. The teacher’s mind, and the materials writer’s mind, is focused on contextualizing a particular structure, and not on communicating ideas. The goal in the mind of the teacher is the learning or acquisition of the rule or word. What is proposed here is that the goal, in the mind of both the teacher and the student, is the idea, the message (ibid, 69). Such kind of communication is an example of authentic language in that in real-life conversations, people do not speak in such full grammatical sentences, and do not keep to a clear sequence of turns (Cook, 1991 cited in Wang, 2010).
A grammatically-based syllabus reduces the quality of comprehensible input and distorts the communicative focus. Teachers will be concerned with how they are speaking, and reading selections will be aimed at including a number of examples of a certain structure along with a certain vocabulary sample. This, Krashen (1982, 70) believes, is a sure guarantee of boring and wooden language. The only instance in which the teaching of grammar can result in language acquisition (and proficiency) is when the students are interested in the subject, and TL is used as a medium of instruction. Very often, when this occurs, both teachers and students are convinced that the study of formal grammar is essential for SLA, and the teacher is skillful enough to present explanations in the TL so that the students understand. In other words, the teacher talk meets the requirements for comprehensible input and perhaps with the students’ participation the classroom becomes an environment suitable for acquisition.
A feasible alternative is a communicatively-based syllabus which depends on collaborative learning or collaborative dialogue (Swain, 2000 cited in Fanyu & Wanyi, 2013). This refers to interactions in which teacher-students/student-student are jointly engaged in problem solving and knowledge building. This notion has been implied in SLL and teaching in terms of mutual knowledge construction with teachers and learning through working with peers in pair work or group activity. This facilitates natural and extensive review of language material and conscious focus of both student and teacher is communication of ideas, rather than merely focusing on accuracy of grammatical structures (Krashen, 1982: 70).
4.2 Other Features that Encourage Acquisition
After reviewing Krashen’s hypotheses about acquisition, the following can be summarized as additional remarks or tips that encourage SLA (ibid, 73-78):
1. A desirable goal is that the students forget, in a sense, that the message is actually encoded in another language. This happens when the foreign language input is presented to the learner as naturally as possible.
2. If the topic being discussed or presented is interesting and comprehensible, much of the pressure normally associated with a language class will be off. Consequently, anxiety will be lowered and acquisition will result.
3. Language teachers and students should work collaboratively.
4. Students should be encouraged to talk from the beginning with speaking fluency.
5. Forcing early production, before the student has built up enough competence through comprehensible input, is perhaps the single most anxiety-provoking thing about language classes. While some students may want to talk as soon as possible, others may feel less secure until they have built up more competence.
6. Error correction should not be adopted as a constant teaching strategy. This is so because it encourages a situation in which the student will try to avoid mistakes, avoid difficult constructions, focus less on meaning and more on form. It may disrupt the entire communicative focus on an exchange.
7. Since overuse of correction has such negative effects for acquisition, and since error correction is not of direct benefit to language acquisition, a safe procedure is simply to eliminate error correction entirely in communicative-type activities. Improvement will come without error correction, and may even come more rapidly, since the input will get in, the filter will be lower and students will be off the defensive (ibid).
8. We need to provide our students with enough input so that they can gain the linguistic competence necessary to begin to take advantage of the informal environment, the outside world. In other words, they need to know enough of the second language so that they can understand significant portions of non-classroom language.
9. Give our students the tools they need to overcome difficulties, to make them conversationally competent. By giving them the means of managing conversations, we can help them to continue improving by allowing them to participate in conversation despite their inadequacies.
10. Help our students to converse despite less than perfect linguistic competence. We should build in them the habit of communicative or conversational competence that can help them gain more comprehensible input; devices that help control the quantity of input, and devices that help control the quality. The former will help the acquirer get more input, the latter will help to make the input comprehensible.
11. Briefly stated, for SLA to occur, the input provided by the teacher, teaching program and surrounding environment should be interesting, relevant, communicative, natural and comprehensive.
5. Viewpoints and Criticism
Despite his popularity and fame which lasted for many years starting from 1970s, he has been a figure of much debate and criticism. He was the best-known figure in the field of language teaching with his theory of second-language acquisition. Krashen’s model was influential in the field of SLA and also had a large influence on language teaching, but it left some important processes in SLA unexplained. Subsequent Research in the 1980s and 1990s was characterized by the attempt to fill in these gaps. These included White’s (1989) descriptions of learner competence and Michael Long’s (1983) interaction hypothesis, Merrill Swain’s output hypothesis, and Richard Schmidt’s noticing hypothesis. (VanPatten and Benati, 2010).
Concerning his theory of SLA and optimal input (in particular), there have been a lot of attention and criticisms. These criticisms began a long time ago, almost as soon as his theory began to attract attention. The best summary of these criticisms is from his most persistent critic, McLaughlin (1987) who objects to the learning/acquisition distinction, saying that it is not well defined and that Krashen’s claims based on it cannot be tested. He has similar complaints about comprehensible input and the Input Hypothesis, namely Affective Filter Hypothesis which are described as vague and not capable of predicting linguistic development. The Monitor doesn’t work as Krashen claims, and the Natural Order Hypothesis is defective because of methodological considerations. To him, nothing works right in Krashen’s theory, and there are many examples of other researchers and writers who disagree with Krashen (ibid).
Among them is Gregg (1985, 81) who challenges Krashen to disprove the more widely held proposition that learning can become acquisition. He also attacks Krashen’s failure to adequately define the terms ‘conscious’ and ‘subconscious’ would seem to indicate either an embarrassing oversight or a serious and academically unforgivable lack of attention to key and determining concepts. A more formal way of evaluating Krashen’s theory is provided by Stem (1983).He raises an important question such as: Is the theory useful and applicable? Many teachers would say Yes, emphatically so; many researchers would strongly disagree. He criticized Krashen theory as vague that it really says nothing. According to Wheeler (2003), a damning accusation against Krashen is that his theory is unverifiable.
As mentioned above, there has been strong controversy and criticism among linguists and researchers as regards Krashen’s theory of SLA. Despite its weak points and pitfalls, the theory has gained fame and importance in the field of language learning and acquisition which cannot be overshadowed or neglected. As for me, l think that the best solution lies in a compromise in which neither pro nor anti attitude should be depended. Despite its pitfalls and weaknesses the theory gave significant contributions to the study and learning of second language which cannot be underestimated.
This paper has provided us with an exposition of SLA from different perspective. At the outset, a distinction has been made between acquisition and learning. SLA has been explained in terms of Krashen’s Theory, namely the Acquisition-Learning Hypothesis, the Monitor Hypothesis, the Natural Order Hypothesis, the Input Hypothesis and the Affective Filter Hypothesis. The most important part of the paper was assigned to characteristics of optimal input and other features that encourage the whole process of SLA. For SLA to occur at its best level, the input provided by the teacher, the surrounding environment and the teaching program should be interesting, relevant, communicative, natural and comprehensive. Last but not least, despite the fame and importance the theory gained in the linguistic arena in the 1970s and 1980s, it was criticized mainly for some deficiencies and drawbacks.
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