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Basic reading skills (BRS) are primarily decoding
and word recognition skills. Tests measuring basic reading skills
typically include tasks such as reading real or nonsense words, an
application of the alphabetic principle--knowing how sounds and
symbols go together.
Broad CHC abilities and BRS.
The following broad CHC cognitive
abilities were consistently significant (low, medium
or high) in the prediction of BRS (see Figure 1) at one or
more age group: comprehension-knowledge (Gc) (medium from
ages 6-13; high at ages 14-19), long-term retrieval (Glr)
(low at ages 6-8), processing speed (Gs) (medium at
ages 6-13), and short-term memory (Gsm) (low at ages 6-8;
high at ages 9-19).
It is not surprising that Gc has strong BRS
relations as ample evidence exists that general language and
vocabulary development, aspects of Gc, are necessary for acquiring
reading skills (Cooper, 2006; Shaywitz, Morris, & Shaywitz,
2008; Torgesen, 2002; Vellutino, Tunmer, Jaccard, & Chen,
2007). Also, the ability to form, store, and retrieve sound-symbol
relations and efficiently retrieve lexical and general knowledge
(Glr) have all been linked to early reading development (Cooper,
2006; Perfetti, 2007; Shaywitz et al., 2008; Vellutino et
al., 2007). The importance of Gsm for reading is consistent with
research that has implicated auditory/verbal/phonological working
or short-term memory (Cooper, 2006; Hammill, 2004; Kintsch, 2005;
Kintsch & Rawson, 2005). Finally, different researchers
(Berninger, Abbott, Thomson, & Raskind, 2006; Kintsch, 2005;
Kintsch & Rawson, 2005; Shaywitz et al., 2008; Wolf, Bowers,
& Biddle, 2000) have emphasized a variety of speed or fluency
constructs in early reading skill acquisition (e.g., rapid
automatic naming; naming speed; speed of semantic or lexical
access; verbal efficiency; automaticity), findings consistent with
the significant Gs finding in this review. The consistency of
significance of Glr and Gs tend to decline with age while the
influence of other abilities, such as Gc and Gsm, increase with age
(see Figure 1). It is likely that Glr and Gs are more important
during the beginning stages of reading when basic skills are first
being acquired and, once BRS are in place, Gc and Gsm become more
important in the development of reading.
The broad abilities of auditory processing (Ga),
fluid reasoning (Gf), and visual processing (Gv) were not
consistently significantly related to BRS. Most surprising may be
that Ga did not meet the criteria for low, medium, or
high significance at any of the ages. The reason for the
lack of broad Ga significance is apparent when one examines the
results of the research at the narrow ability level.
Narrow CHC abilities and
BRS.
Phonetic coding (Ga-PC) was classified
medium at all three age levels (see Figure 1), a finding
supporting the importance of phonemic awareness in BRS, despite the
lack of significance for a broad Ga/BRS relationship. This
finding is consistent with research (Berninger et al., 2006;
Cooper, 2006; Shaywitz et al., 2008; Torgesen, 2002) indicating
that awareness of sounds is a prerequisite skill for mastering the
alphabetic principle in reading (e.g., Adams, 1990; Ehri, 1998) and
that a phonological core deficit exists in many individuals with
dyslexia (e.g., Morris et al., 1998; Stanovich & Siegel,
1994).
The broad Gc/BRS significant findings appear
related to three different narrow Gc abilities. General
information (Gc-K0) was consistently related to BRS at all ages,
with a trend towards increased importance with increasing age
(low at ages 6-8; medium at ages 9-19). This finding
is consistent with the importance of prior background knowledge,
knowledge integration, and general fund of cultural knowledge in
reading (Cooper, 2006; Kintsch & Rawson, 2005). Listening
ability (Gc-LS) was classified medium at the youngest age
group (6-8 years), a finding consistent with research that has
implicated the ability to comprehend spoken language (i.e.,
listening comprehension) in reading development (Hoover &
Gough, 1990; Joshi & Aaron, 2000).
Three different narrow memory abilities (Gsm and
Glr), particularly those of a short- term nature (Gsm), appear
important for BRS. Memory span (Gsm-MS) was not significant at ages
6-8 but was medium for ages 9-19. In contrast, working
memory (Gsm-MW) was consistently classified medium at all
age levels (see broad Gsm discussion for references regarding the
importance of memory span and working memory in reading).
Associative memory (Glr-MA) was only related (low) to BRS at
the youngest ages (6-8 years), a finding consistent with research
that has demonstrated that paired-associate learning, such as
learning phoneme-grapheme relationships (Cooper, 2006; Hammill,
2004; Perfetti, 2007; Shaywitz et al., 2008), makes a unique
contribution to predicting early reading (Windfuhr & Snowling,
2001).
The driving force behind the broad Gs/BRS finding
appears to be the influence of the narrow perceptual speed (Gs-P)
ability, which was consistently significant at all ages (low
at ages 6-8 and 14-19; medium at ages 9-13). The importance
of Gs-P is not surprising given the confirmed relationship between
perceptual speed, speed of processing, and the need for
automaticity in integrating phonological and orthographic codes in
word reading (e.g., Barker, Torgesen, & Wagner, 1992;
Berninger, 1990; Hale & Fiorello, 2004; Joshi & Aaron,
2000; Urso, 2008).
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Reading comprehension (RC) is constructing
meaning from text through a complex process that integrates
multiple linguistic factors. Tests measuring reading comprehension
include tasks that require word knowledge and understanding
passages usually demonstrated through multiple-choice, open- ended,
or cloze procedures.
Broad CHC abilities and
RC.
Several broad CHC abilities were consistently
significant (low, medium, or high) in predicting
reading comprehension at one or more of the age groups:
auditory processing (Ga) (medium at ages 6-8),
comprehension-knowledge (Gc) (high at all ages), long-term
retrieval (Glr) (low ages 9-13), and short- term memory
(Gsm) (low at ages 6-8 and 14-19).
Broad Gc displayed the most consistent relation
to reading comprehension across all ages levels, a finding
reinforced by studies that have demonstrated the important role of
general language development and vocabulary (e.g., Baker, Simmons,
&Kame’enui, 1995; Coyne, Simmons, Kame'enui
&Stoolmiller, 2004; Jenkins, Van den Broek, Espin, & Deno,
2003; Perfetti, 2007) and prior knowledge (e.g., Anderson
&Pearson, 1984; Kintsch & Rawson, 2005; Nation, 2005) in
reading comprehension. In fact, Floyd, Bergeron and Alfonso (2006)
reported broad Gc levels as the primary difference between
individuals with good and poor comprehension. Research supporting
the significant relations for Ga and Glr abilities with reading, in
this case RC, was discussed in the previous basic reading skills
(BRS) section and will not be repeated here.
Broad abilities not consistently significant at
any of the three age groups include processing speed (Gs), fluid
reasoning (Gf), and visual processing (Gv). However, Gs was
classified tentative/speculative at the younger ages (ages
6-13), which is consistent with Keith’s (1999) research. The
Gf tentative/speculative classification, only at the oldest
age group (14-19 years), is suggestive of Gf involvement at
higher-levels of reading comprehension, a finding consistent with
other research linking Gf and RC (e.g., Floyd et al., 2006; McGrew,
1993; Nation, Clarke, & Snowling, 2002). The
tentative/speculative RC findings for Gs and Gf may be
partially explained by the narrow abilities in the current research
synthesis.
Narrow CHC abilities and
RC.
Given the complex cognitive demanding nature of
reading comprehension (Baddeley, Logie, Nimmo- Smith, &
Brereton, 1985; Perfetti et al., 2007), it is not surprising that
working memory (Gsm-MW) displayed a high classification at
all ages. Memory span (Gsm-MS) was consistently significant
(medium) only from ages 14-19. We hypothesize that
this finding is related to the inclusion of longer items (lengthy
oral sentences) at the top end of most MS tasks, items which
increase the demand for listening comprehension or listening
ability (Gc-LS), versus simpler rote MS. Listening
comprehension is frequently cited as a good predictor of reading
comprehension (Aaron & Joshi, 1992; Cooper, 2006). The
importance of broad Gc for RC appears due to the narrow abilities
of general information (Gc-K0) and listening ability (Gc-LS) which
were consistently significant (high for all age
groups).
While broad Ga was only consistently significant
(medium) at ages 6-8, phonetic coding (Ga-PC) was implicated
at all ages (low at ages 6-8 and 14-19;
tentative/speculative at 9-13). A possible explanation of
these age-differentiated findings is the observation (from
inspection of the on-line summary coding table for reading
comprehension) that six of the nine significant PC-RC analyses came
from McGrew’s (2007) multiple regression manifest variable
study that used the WJ III tests (versus clusters) as IV’s.
The WJ III Sound Awareness test has been reported to be a possible
mixed measure of phonetic coding (Ga-PC) and working memory
(Gsm-MS; see Schrank, 2006). When Sound Awareness was significantly
related to a WJ III achievement dependent variable, McGrew (2007)
double coded it as reflecting significance for both PC and
MW. Thus, it is possible that the Ga-PC/RC significance may be
related to influence of Ga-PC abilities at the youngest ages (6 to
8) and the more complex Gsm-MW component at the older ages (14 to
19).
Again demonstrating the importance of narrow (vs
broad) cognitive abilities in understanding achievement are the Glr
and Gs broad and narrow ability findings. Meaningful memory
(Glr-MM) had a high classification from ages 9-19 and naming
facility (Glr-NA) was medium at ages 9-13 and low at
ages 14-19, while broad Glr was only salient (low) at ages
9-13. Individuals with RC difficulties often display problems
with verbal fluency, word retrieval, naming facility, or speed and
quality of lexical access (e.g., Kintsch, & Rawson, 2005;
Nation, Marshall, & Snowling, 2001; Shaywitz et al., 2008)
which is consistent with the Glr-NA/RC findings reported here.
Similarly, despite broad Gs not being identified consistently
significant at any age, narrow perceptual speed (Gs-P) was
significant at all ages (medium, medium, low). A strong
relationship between reading comprehension and quick and automatic
processing of letters and words (fluency) and word reading speed
(e.g., Fuchs, Fuchs, Hosp, & Jenkins, 2001; Jenkins, et al.,
2003) is consistent with the strong perceptual speed (Gs-P) and RC
findings.
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Basic math skills (BMS) include arithmetic and
computational skills. Tests measuring basic math skills usually
include tasks ranging in difficulty from basic math facts to
solving more complex algorithmic computations.
Broad CHC abilities and BMS.
The following broad CHC cognitive abilities were
consistently significant (low, medium, or high) in
the prediction of BMS at one or more age group:
comprehension-knowledge (Gc) (medium at ages 9-19); fluid
reasoning (Gf) (medium at all ages); and processing speed
(Gs) (medium at all ages). Language skills (aspects of broad
Gc) have been linked to math (e.g., Fiorello & Primerano, 2005;
Flanagan et al., 2006; Floyd, Evans, & McGrew, 2003; Fuchs et
al., 2006; McGrew, 2008; Swanson & Jerman, 2006) especially as
Gc relates to the development of number concepts (e.g., Carey,
2004; Gelman & Butterworth, 2005) and the retrieval of math
facts (Chong & Siegel, 2008). The importance Gf in the
prediction of math achievement is consistent with considerable
research (e.g., Fiorello & Primerano, 2005; Floyd et al., 2003;
Flanagan et al., 2006; Fuchs et al., 2006; Geary, 1993, 2007;
Rourke & Conway, 1997). The Gs-to-arithmetic skill link
(Bull & Johnston, 1997; Fiorello & Primerano, 2005; Floyd
et al., 2003; Fuchs et al., 2006) has been explained in terms of
counting speed (Geary, 1993, 2007), numerical processing fluency
(Swanson & Jerman, 2006) and efficiency and consistency of
execution of simple cognitive tasks during math (Fuchs et al.,
2006; Geary, 1993, 2007).
The broad abilities of Ga, Gv, Glr, and Gsm were
not consistently significant at any age, findings inconsistent with
prior research. Glr and Gsm were found predictive of math skills
throughout childhood and adolescence by Floyd et al. (2003).
Semantic retrieval, an aspect of Glr, has also been reported to
contribute to math disabilities in college students (Cirino,
Morris, & Morris, 2002). Further, the ability to fluently
retrieve math facts from memory, a Glr function, is the most
consistent BMS deficit associated with MD (e.g., Garnett, Frank,
& Fleischner, 1983; Geary, 1990, 1993; Geary, Hamson, &
Hoard, 2000; Goldman, Pellegrino, & Mertz, 1988). Most of the
above inconsistencies can be further explained, and to some extent,
resolved by inspecting the narrow ability findings for BMS.
Narrow CHC abilities and
BMS.
As was the case for BRS and RC, the current
findings suggest that the narrow cognitive abilities may play an
important role in the prediction of basic math achievement even
when the corresponding broad ability does not. For example, broad
Ga was not significant at any age group, but phonetic coding (Ga-
PC) displayed a medium level of consistent significance at
ages 6-13 and was tentative/speculative at ages 14-19.
Phonological processing (Ga-PC in CHC taxonomy) has been reported
to predict arithmetic achievement (e.g., Leather & Henry, 1994;
Rasmussen & Bisanz, 2005) and is associated with MD and low
math achieving children with fact fluency deficits (Chong &
Siegel, 2008). Phonological processing has been hypothesized to
influence computation skills since speech sound processes are used
when solving problems (Bull & Johnston, 1997; Geary, 1993;
Rourke & Conway, 1997) and counting requires retrieval of the
phonological codes for number words (Geary, 1993; Logie &
Baddeley, 1987).
Perceptual speed (Gs-P) was consistently
significant at a high level for all age groups.
The Gs-P/BMS link may be a function of “subitizing,”
which is the ability to instantly see “how many”
without counting. Subitizing underlies development of fluency with
math facts which is thought to be a core deficit in MD (e.g.,
Geary, 1993; Jordan, Hanich, & Kaplan, 2003).
Alternatively, since all the significant Gs-P findings involved the
WJ III Visual Matching test (either alone or when combined with
another perceptual speed test; Keith, 1999; McGrew, 2007; McGrew
& Hessler, 1995)9, a test requiring rapid recognition of
similar digit pairs in a line of numbers, an alternative
explanation may be that the Gs-P/BMS may be due to number facility
(Gs-N) ability. Working memory (Gsm-MW), which was consistently
significant (high for all ages) is frequently cited as
important for BMS (e.g., Geary, 1993, 2007; Geary, Brown, &
Samaranayake, 1991; Hitch & McAuley, 1991; Passolunghi,
Mammarella, & Altoè, 2008; Swanson & Jerman, 2006) and
is also suggested as a core deficit for individuals with MD (e.g.,
Bull, Espy, & Wiebe, 2008; Chong & Siegel, 2008; Geary,
2003; Koontz & Berch, 1996; Passolunghi & Siegel,
2001).
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Math reasoning (MR) is problem-solving skills in
math. Tests measuring MR typically include word problems, number
series, concepts, and application of mathematical operations and
concepts. Achievement in MR will depend, to some extent, on
proficiency with basic math skills.
Broad CHC abilities and MR.
Several broad CHC abilities were consistently
significant (low, medium, or high) in predicting math
reasoning at one or more of the age groups: comprehension-
knowledge (Gc) (low at ages 6-8, medium at ages 9-13,
high at ages 14-19); fluid reasoning (Gf) (high at
ages 6-13 and medium at ages 14-19); processing speed (Gs)
(mediumat ages 6-13); and short-term memory (Gsm)
(low at ages 14-19). Much research supports the strong
predictive nature of Gc for mathematics (e.g., Hale, Fiorello,
Kavanagh, Hoeppner, &Gaither, 2001; Keith, 1999; McGrew et al.,
1997) and the association between MD and limited oral language
abilities (Fuchs et al., 2008; Proctor, Floyd, & Shaver, 2005).
Furthermore, the importance of Gc increased with age, a finding
consistent with the increased linguistic demands of more complex
math reasoning tasks (e.g., Fuchs et al., 2006, 2008; Geary,
1994).
The Gf finding is consistent with a body of
research that identifies Gf as important to math reasoning (e.g.,
Fiorello &Primerano, 2005; Floyd et al., 2003; Fuchs et al.,
2006; Geary et al., 2007; McGrew, 2008; Rourke & Conway, 1997).
Fluid reasoning is a strong predictor of math achievement (Hale,
Fiorello, Kavanagh, Holdnack, & Aloe, 2007) and is often
significantly impaired in individuals with MD (Geary, 2007; Proctor
et al., 2005). Finally, Gs has also been identified as an important
predictor of MR (e.g., Floyd et al., 2003; Geary, 2007; Swanson
& Jerman, 2006) possibly facilitating reasoning by freeing up
cognitive resources in working memory for higher level complex
processing and thinking (e.g., Bull & Johnston, 1997; Fuchs et
al., 2006).
The current review did not identify broad Ga,
Glr, or Gv as consistently significant for math reasoning at any
age group. While these non-significant findings are consistent with
the Flanagan et al. (2006) review, other research is contradictory.
Floyd et al. (2003) reported a moderate relationship between math
achievement and Glr and Ga. As discussed next, the current review
found several narrow Glr or Ga abilities to be significant
predictors of math reasoning even though the broad cognitive
abilities were not.
Narrow CHC abilities and
MR.
Phonetic coding (Ga-PC) was classified as
medium in consistency of significance at ages 6-8 and
low for ages 9-19. A number of studies have implicated the
phonological system as underlying individual differences in math
problem-solving (e.g., Furst & Hitch, 2000; Gathercole &
Pickering, 2000; Geary & Brown, 1991; Swanson & Sachse-Lee,
2001). As noted for BMS, research has implicated the importance of
perceptual speed (Gs-P), such as rapid processing of numbers and
counting speed, for math performance (e.g., Geary et al., 2007;
Fuchs et al., 2006; McGrew, 2008). This was supported in the
current review when perceptual speed (Gs-P) displayed a
medium level of consistent significance with MR across all
age groups.
Two narrow Gsm abilities were important in the
prediction of MR at one or more age group: memory span (Gsm-MS) was
low for ages 6-8 and working memory (Gsm-MW) was high
at all ages. Other research supports these findings as memory span
(Gsm-MS) has been related to performing mental arithmetic and how
quickly numbers can be counted (Geary, 1993; Holmes & Adams,
2006). Considerable research confirms the importance of working
memory (Gsm- MW) for math reasoning (e.g., Fuchs et al., 2008;
Geary, 2007; Passolunghi, 2006). Both the phonological loop (e.g.,
Furst & Hitch, 2000; Gathercole & Pickering, 2000; Geary,
2007) and visual-spatial sketchpad (e.g., Geary, 2007; Holmes
&Adams, 2006), components of working memory (Gsm-MW),
contribute to math reasoning performance.
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