Language processing is a new discipline which emerged from the pioneering works during the mid-twentieth century by Naom Chomsky, who emphasized language as a biologically rooted form as opposed to a cultural code.
The apparently simple task of language processing is considerably more complicated than its appearance. It involves a speaker and a listener, and a medium through which communication takes place. The speaker retrieves words from memory, and goes through a process of arrangement and production to convey a thought. In the process the speaker transforms incidents from the mental domain into sounds which is received by the listener. In turn the listener recreates the speaker"s thoughts in some analogous form in his/her mind. Considering the complications involved most of the theories endeavor to explain language production and comprehension in terms of interplay between cognitive processes and the language knowledge processed by everyone. Research works, during the last 25 years, have been directed in two principal directions; the moment-by-moment unfolding of meaning during comprehension (understanding) and an understanding of the way speakers formulate their speech (talking). It is believed that speakers as well as listeners deal with three kinds of tasks during the communication process; cognitive, linguistic and communicative.
In language production, studies of errors in speech has shown that the act of finding and saying a word, in fact, involves a complicated (and fast assembly) process of separate, interlocking features. It shows that people"s knowledge about words comes in separate pieces dealing with semantic, syntactic and phonological properties of words, indicating a sophisticated cognitive process. There is, however, some disagreement in the dynamics of retrieval leading to the interactive and modular views of this phenomena. Linguistic processes involved in production deals with construction of utterances based on certain rules of grammar. Finally, communicative processes in language production has an impact on what is said. The production changes depending on the characteristics of the listener (in relation to the speaker), the place and the time of production.
Similarly, language comprehension also deals with the three areas mentioned above. In essence, comprehension involves attempts towards clarification of ambiguities in the stimulus information. In terms of cognitive processes, ambiguities arise from identifying spoken words. It has been shown that listener"s efficient use of knowledge as well as the context has an influence on the ease with which ambiguities are solved. In linguistic processes, the main tasks seem to be involved in successful identification and segmentation of word-like stretches. Common ambiguities are associated with alternative meanings and grammatical classes. Finally, communicative processes associated with understanding deals with the relation between linguistic expressions and the things they represent. Ambiguities arise from improper referential grounding as well as identification of events and entities intended by the speaker.