The following image presents the elements of the reading process as a flow chart that roughly identifies levels of reading processing. I ask you to imagine a reader holding a text within the hands. Whether or not any comprehension occurs begins at the fundamental first steps: is adequate attention being paid to the text? Does the reader have the language and the knowledge to adequately draw meaning from the text? It is a process of both top down and bottom up processing, in which the top down process brings background knowledge and prior experience to bear on the reading and the bottom up process involves decoding, defining new terminology, and making sense of sentences through a knowledge of a syntax.
The following diagram further represents how both top down and bottom up processes interplay in an interactive approach to reading instruction.
Courtesy of Dr Neil Anderson, Brigham Young University