A. Affective Filter Hypothesis
Early in 1870‟s, Dulay and Burt had proposed the Affective Filter Hypothesis and explained its influence on the
foreign language learning process. Later, Krashen(1982, P. 31) developed and made the hypothesis perfect. He put the
theory into five central hypotheses in second language acquisition (hereafter SLA), namely, the Acquisition-learning
distinction; the Natural order hypothesis; the Monitor hypothesis; the Input hypothesis and the Affective Filter
Hypothesis. Krashen argued that affective filter is a kind of psychological obstacle that prevents language learners from
absorbing available comprehensible input completely. He looked affective factors functioning as a filter that reduces the
amount of language input the learner is able to understand. It has a close relationship with the language learner‟s input
and intake. It can be said that affective factors determine the proportion of language learners‟ input and intake. The
affective factors include certain emotions, such as motivation, self-confidence, anxiety, and so on in the process of
acquiring a second language. These negative emotions prevent efficient processing of the language input, and on the
contrary, the positive emotions promote the efficiency of the process. When language learners with high motivation,
self-confidence and a low level of anxiety, they have low filters and so receive and take in plenty of input. On the other
hand, learners with low motivation, little self-confidence and a high level of anxiety have high filters and therefore
obtain little input. The Affective Filter Hypothesis shows that the emotional factors strongly affect the learners‟ input
and how much input is converted into intake. The Affective Filter Hypothesis has significant implications for foreign
language teaching. A low filter should be created and advocated for the effective language teaching. It can be guessed
that learners‟ affective filters will be influenced by teachers‟ feedback. Attempts should be made to lower the affective
filter and let learners feel less stressed and more confident in a comfortable learning atmosphere.
It has a long history about interest in affective factors in education abroad. Since 1970s, the interest in the field of
foreign language learning and teaching has been raised. Inferences of affective factors have become the major concern
in this research field. Many researchers have stressed the importance of understanding affective factors in second
language learning. For example, Arnold (2000, P. 2) gives out two reasons to explain the importance. Firstly, “attention to affective aspects can lead to more effective language learning”. Secondly, attention to affective aspects can contribute
to the whole-person development, which is “beyond language teaching and even beyond what has traditionally been
considered the academic realm”. It can be deduced that affective factors do play a significant role in both foreign
language learning and teaching. Three factors: motivation, self-confidence and anxiety have been chosen to state their
important functions.