Processing of Bottom-Up and Top-Down Information by Skilled and Average Deaf Readers and Implications for Whole Language Instruction

Article excerpt

If we identify those components of competence that enable skillful reading by the relatively few deaf youth who are proficient readers, this knowledge may suggest instructional goals that will help the many deaf youth with low reading ability. (Although the word deaf has been used in recent years to designate cultural group membership [see Dolnick, 1993], here the term is used exclusively to denote a measured hearing loss that is severe to profound in degree.) Guided by a cognitive view of literacy processes and by previous research with deaf readers, I have studied possible differences between skilled and average deaf secondary readers. Specifically, the two ability groups were compared on two categories of reading tasks. The first category reveals fluency in processing the detailed, visual information of text. A second category measures a reader's tendency to engage in higher-level processes, which focus on meaning. A finding that skilled readers can be distinguished by their effective use of higher-level processes would argue for accelerating the use of whole language instructional strategies. This increasingly popular approach to literacy development emphasizes readers' use of the semantic information that they bring to or generate from text. in the whole language view, processing of visual information is accorded secondary importance. However, if fluency in processing the visual information of text can distinguish between the two groups, this would assert the necessity for instruction that develops efficient processing of visual information.

COGNITIVE THEORY AND READING

According to cognitive views of the reading process (see Carpenter & Just, 1981; Rumelhart, 1977; Stanovich, 1980) readers may use various kinds of information, which are available either on the printed page or from the long-term memory of the reader. They construct mental productions of text that integrate their knowledge of English letter combinations, phonology, syntax, semantics, pragmatics, discourse structure, episodic knowledge, and domain knowledge. The kinds of information appearing early in the preceding taxonomy - letter combinations, phonology, and syntax - are frequently referred to as "bottom-up" constraints. These are the specific visual data that readers actually perceive on the printed page. The types of information later in the taxonomy are often characterized as "top-down." Once activated in the mind of a reader, these concepts work "downward" to guide interpretation of the detailed information on the printed page.

The various kinds of constraints interact with each other, sometimes informing and sometimes compensating for one another. However, these interactions occur within the limited space of the reader's "working memory," the faculty used by the mind to temporarily store data that hold our attention. The limited capacity of working memory makes it difficult for readers to process many textual constraints at the same time, and the impermanence of working memory contents necessitates swift processing of words and constraints to avoid decay of information before it contributes to the meaning that is constructed. Research by Daneman and Carpenter (1980) and Perfetti (1985) has indicated that slow readers are susceptible to decay of working memory contents. According to Shankweiler and Crain (1986), working memory capacity is functionally enlarged by use of phonological strategies for sustaining words in working memory, a phenomenon with obvious implications for deaf readers.

Stanovich (1980) theorized a "compensatory" interaction among the constraints of a text, and this is another critical concept of theory related to reading and cognition. He described a compensatory relationship as occurring when a reader's deficient knowledge relative to one constraint is offset by greater reliance on knowledge of one or more other constraints in which competence is relatively superior. As a consequence, the reader is able to construct a reasonable understanding of the text. …