processing deficits (e.g., Mann, 1991; Velluntino, 1979). Some other researchers,

however, have demonstrated evidence that reading involves a combination of multiple

factors related to an individual's experiences, ability, and neurological functioning. Some

of the latter researchers argue that visual abilities contribute to children's reading abilities

(e.g., Eden et al.,1995; Lovegrove, Garcia, & Nicholson,1990; Rayner, 1997; Watson,

1990 ). However, such studies of reading-related visual skills yield inconsistent findings.

Some researchers were able to find that there is a significant difference in visual skills

between children with RD and non-RD (e.g., Morad, Lederman, Avni, Atzmon, Azoulay,

& Segal, 2002) while some were not (e.g., Velluntino, 1987).

 In the context of discussions of visual deficits, there is an increasing consensus on

the hypothesis that these processing problems may not be general but may characterize a

small group of severely affected children. It means that not all children with RD have

visual processing deficit but some of children may have visually related reading

problems. If all children with reading disabilities receive the same type of instruction,

which is solely based on phonological awareness, the programs may not be beneficial for

a group of children who have reading disabilities that are associated with other factors

such as a rapid-naming deficit and a visual deficit. Therefore, we should be aware of

subgroups of reading disabled children for effective early identification and intervention.

A Continuing Attention on Phonological Awareness Research

 Over the past two decades, no area of reading research has caught as much

attention as phonological awareness. The term "phonological awareness" began

appearing in the research literature in the late 1970s and early 1980s (Clark & Uhry,

1995). Early research on phonological awareness recognized that most poor readers have

difficulty tapping out the number of phonemes in a word as well as in adding or deleting