ABSTRACT
This chapter provides the opportunity for contextual influences on the functional stimulus to be manifested in the data patterns. It explains the nature of the functional stimulus in reading—that is, what aspects of the text stimulus are being attended to or used for reading. Given that the eyes are centered at a certain location for a fixation and that attention is given to a particular region of the text, the final question concerns whether language constraints influence what aspects of the text are used in reading. Contextual information refers to all other information the reader has up to that point that places constraints on what the presently available visual information might be. Thus the reader's knowledge of the language and of the topic being discussed may be brought into play to aid perception by guiding the eyes in a manner that contributes to efficiency.
