二语习得文献综述

Chapter ⅠIntroduction of Attention

1.1 What is Attention?

The word attention in dictionary is defined as the action of applying one’s mind to something or somebody or noticing something or somebody, a kind of particular care. As an important concept in psychology, attention refers to the cognitive process of selectively concentrating on one thing while deliberately ignore other things. Among the various cognitive process in human mind, attention is usually considered as the most important. A leading psychologist William James gave us a clear definition: “everyone knows what attention is. It is the taking possession by the mind in clear and vivid form, of one out of what seem several simultaneously possible objects or trains of thought…it implies withdraw from something in order to deal effectively with others.( William James. 1890)

Today, rather than regarding attention as a filter on input most psychologists now conceptualize it as a mechanism of cognitive processing and more specifically another instance of construction：depending on what stimulus they wish to pay attention to, people select certain pieces of information from among those they receive and construct a perception from them．

The first and most basic characteristic of the mind is that it can only focus effectively on one thing at a time and can only focus on the selected goal for a short period of time before it shifted to something else．Thus, the processing capacity is limited. But sometimes the amount of new information being attended to depend on how many cognitive processing resources is needed for each stimulus. If you are confronted with a demanding task，full attention is required to accomplish it ．However, if you are doing habitual or automatic routine, you may split your attention to other activities．Therefore，it is safe to say that human cannot attend to two demanding tasks at the same time．Therefore, people should select information for processing according to priority.

The second characteristic is that human mind is always occupied by a continual stream of thoughts and considerations without any rest. Therefore, focusing on one thing is realized by subjectively choosing a goal to attend to at a certain period of time, not just by blocking out distractions.

1.2 Vocabulary Knowledge and Vocabulary Acquisition Process

No doubt, foreign language vocabulary is viewed as a footstone factor in successful communication (Ellis 1994)and，to a great extent，in high-level reading ability and comprehension. A large number of the studies in SLA examine the role of context in vocabulary acquisition which takes place through reading or reading-associated tasks．Context plays a primordial role in this acquisition by supplying the necessary input and trigger．A plausible explanation of lexical acquisition is a theory about the active role of the learner in the process of vocabulary acquisition．Learners should be encouraged to make their own lexical associations when they are actively learning new vocabulary.

The importance of vocabulary knowledge in L2 learning is supported by the schema-based approach to language learning．The learning theory based on information processing and the role of cognitive processes suggests that the information from long-term memory can be used to enrich the learners’understanding or retention of the new ideas by providing related information or schemata into which the new ideas call be organized．An often quoted definition of learning is the process by which information is obtained，stored，retrieved and used．Learning in itself cannot be separated from what is being learned or from the process of learning．For the learning of L2 vocabulary, Brown(1993)has identified five steps：

(a)having sources for encountering new words；

(b)getting a clear image，either visual or auditory or both, of the forms of the new words；

(c)learning the meaning of the words；

(d)making a strong memory connection between the forms and the meanings of the words；(c)using the words．

Accordingly, learning L2 vocabulary is，to some extent，related to these five steps，which，in a more or less degree，is associated with the attention mechanism in the cognitive process of L2 lexical acquisition. Lexical knowledge lies at the core of L2 vocabulary acquisition but as Laufer observe，“no clear and unequivocal consensus exists as to the nature of lexical knowledge”．

According to Nation (2004) vocabulary learning process consists of three psychological conditions：noticing，retrieval and creative use．Noticing，the first process is induced by, for