With regard to language processing, it is now generally recognized that learners need to
adopt both top-down and bottom-up processing strategies. Bottom-up processing strategies
emphasize the individual components of spoken messages: the phonemes and individual
lexical and grammatical elements which need to be understood in order to understand the
messages. Top-down processing strategies emphasize the macro-features of text such as
the speaker’s purpose and the topic of the message (Nunan, 1998). Chaudron & Richards
(1986 cited in Habibi, Jahandar & Khodabandehlou, 2013) explained that top-down
processing includes prediction and inference based on facts, propositions and expectations.
That is to say it is rather possible to comprehend the meaning of a word prior to decoding
its sounds, as individuals have many kinds of knowledge, including world knowledge.
This view is taken from real life situations in which one knows what basically occurs and
consequently has expectations of what one will hear. Therefore, top-down processing,
occurs from an internal source from background knowledge and world expectations. It was
asserted by Richards (1990) that an understanding of the role of bottom-up and top-down
processes in listening is the heart of listening comprehension. Even though the cognitive
process of listening cannot be observed, comprehending the listening process can be useful in
rethinking the methods of teaching listening.