Access to this full-text is provided by Frontiers.
Content available from Frontiers in Psychology
This content is subject to copyright.
fpsyg-07-01997 December 19, 2016 Time: 12:27 # 1
ORIGINAL RESEARCH
published: 21 December 2016
doi: 10.3389/fpsyg.2016.01997
Edited by:
Ann Dowker,
University of Oxford, UK
Reviewed by:
Angela Jocelyn Fawcett,
Swansea University, UK
Rod Nicolson,
University of Sheffield, UK
*Correspondence:
Deny Menghini
deny.menghini@opbg.net
Specialty section:
This article was submitted to
Developmental Psychology,
a section of the journal
Frontiers in Psychology
Received: 29 April 2016
Accepted: 08 December 2016
Published: 21 December 2016
Citation:
Giovagnoli G, Vicari S, Tomassetti S
and Menghini D (2016) The Role
of Visual-Spatial Abilities in Dyslexia:
Age Differences in Children’s
Reading? Front. Psychol. 7:1997.
doi: 10.3389/fpsyg.2016.01997
The Role of Visual-Spatial Abilities in
Dyslexia: Age Differences in
Children’s Reading?
Giulia Giovagnoli1,2 , Stefano Vicari1, Serena Tomassetti1and Deny Menghini1*
1Department of Neuroscience, Bambino Gesù Children’s Hospital, IRCCS, Rome, Italy, 2Department of Human Studies,
LUMSA University, Rome, Italy
Reading is a highly complex process in which integrative neurocognitive functions
are required. Visual-spatial abilities play a pivotal role because of the multi-faceted
visual sensory processing involved in reading. Several studies show that children with
developmental dyslexia (DD) fail to develop effective visual strategies and that some
reading difficulties are linked to visual-spatial deficits. However, the relationship between
visual-spatial skills and reading abilities is still a controversial issue. Crucially, the role that
age plays has not been investigated in depth in this population, and it is still not clear
if visual-spatial abilities differ across educational stages in DD. The aim of the present
study was to investigate visual-spatial abilities in children with DD and in age-matched
normal readers (NR) according to different educational stages: in children attending
primary school and in children and adolescents attending secondary school. Moreover,
in order to verify whether visual-spatial measures could predict reading performance,
a regression analysis has been performed in younger and older children. The results
showed that younger children with DD performed significantly worse than NR in a mental
rotation task, a more-local visual-spatial task, a more-global visual-perceptual task and
a visual-motor integration task. However, older children with DD showed deficits in the
more-global visual-perceptual task, in a mental rotation task and in a visual attention
task. In younger children, the regression analysis documented that reading abilities are
predicted by the visual-motor integration task, while in older children only the more-
global visual-perceptual task predicted reading performances. Present findings showed
that visual-spatial deficits in children with DD were age-dependent and that visual-spatial
abilities engaged in reading varied across different educational stages. In order to better
understand their potential role in affecting reading, a comprehensive description and a
multi-componential evaluation of visual-spatial abilities is needed with children with DD.
Keywords: learning disabilities, reading deficits, visual-spatial deficits, developmental disabilities
INTRODUCTION
Developmental dyslexia (DD) is a specific learning disorder characterized by persistent difficulties
in learning how to read accurately, fluently, and in reading comprehension caused by multiple
genetic and environmental risk factors, as well as their interplay (Peterson and Pennington, 2015).
The reading deficit should be sufficiently severe as to interfere with academic and occupational
Frontiers in Psychology | www.frontiersin.org 1December 2016 | Volume 7 | Article 1997
fpsyg-07-01997 December 19, 2016 Time: 12:27 # 2
Giovagnoli et al. Visual-Spatial Abilities in Children with Developmental Dyslexia
performances or with activities of daily living and it cannot
be strictly due to intellectual disabilities, sensory disorders or
inadequate educational instruction for it to be considered DD
(American Psychiatric Association [APA], 2013). The ability to
read entails the ability to transform written symbols, namely
letters, into their corresponding sound and, then, to integrate
these sounds onto one single word.
Developmental dyslexia is commonly described as a language-
based disorder, in which the phonological domain is often
compromised (Swan and Goswami, 1997;Snowling, 2000;Ramus
et al., 2003;Shaywitz and Shaywitz, 2005; for a review Peterson
and Pennington, 2012). However, several studies demonstrated
that reading is a complex cognitive process, in which not only
phonological skills, but also auditory sensory processes, memory
abilities, attention processes, automatization and visual-spatial
skills are involved (Nicolson and Fawcett, 1990;Pennington,
2006;Menghini et al., 2010b).
More specifically, visual-spatial processes have been
documented to play a crucial role in reading and a number
of studies reported a relationship between visual-spatial deficits
and DD (Felmingham and Jakobson, 1995;Talcott et al., 1998,
2000;Vidyasagar and Pammer, 2010;Stein, 2014;Gori and
Facoetti, 2015). However, contrasting results have been found
in investigating visual-spatial abilities in DD. Behavioral studies
demonstrated visual-spatial deficits in individuals with DD as
they were shown to be impaired in different motion perception
tasks (Menghini et al., 2010b;Boets et al., 2011;Gori et al.,
2014, 2015), visual recognition tasks (Geiger et al., 2008) or
in mental rotation tasks (Rüsseler et al., 2005). Consistently,
a study by Winner et al. (2001) showed that adults and high
school or undergraduate students with DD did not perform as
successfully as control group in mental rotation, visual memory,
spatial word problems and visual logical matrices regardless
of attentional problems. Nevertheless, others studies failed to
find similar deficits (Corballis et al., 1985;Del Giudice et al.,
2000;Ramus et al., 2003;White et al., 2006). For example, in
a study investigating the role of sensorimotor impairments in
DD, no difference between motion coherence and visual stress
has been found between aged-school children with DD and
controls matched on gender, age and non-verbal IQ (White
et al., 2006). A study carried out on high school students
(von Károlyi et al., 2003) reported better performances in
participants with DD with respect to normal readers (NR) in a
specific visual-spatial task, such as rapid and accurate holistic
inspection.
A crucial aspect for disentangling inconsistencies in the
existing literature on visual-spatial abilities in DD could be
the understanding of age-related changes in visual-spatial
abilities and their relationship with reading. Indeed, the visual-
spatial processing required changes for reading depends on the
developmental reading phase (Hautus et al., 2003). Reading in
children begins with the perception of letters and the analysis
of their conventional phonetic value (Luria, 1966). To identify
words, a child must first be able to recognize individual letters and
perceive their ordering in space (Vernon, 1957). This is followed
by a complex process: matching a symbol with a sound, putting
them together and decoding symbols in order to construct
or derive meaning. As reading skills develop, the analysis of
individual letters is transformed into the direct recognition of
words by sight (Luria, 1966;Ehri, 1987;Kuhn et al., 2006). Indeed,
as children improve their reading skills, they start to recognize
some words as a whole by their characteristic shape. In this
expert stage of reading many processes are automatic, freeing
up cognitive resources so that the readers possess semantic and
syntactic information that enables them to form expectations
about upcoming words in text and can reflect on meaning
(Goodman, 1970). Fluent and automatic reading is thought to
be achieved at the end of primary school (Schwanenflugel et al.,
2006).
During primary school, a child will often devote a significant
amount of mental capacity to the process of decoding, thus
allowing the child to improve their decoding skills with the
ultimate goal of developing the automatic process, as it is for
most skilled readers with most text they encounter. As the skill of
decoding improves and the more automatic it becomes, the more
the child has mental capacity to devote to comprehension.
Many cognitive factors are involved in the process of learning
how to read. During the earlier educational stages, children
examine written words by a sequential decoding, in which
attention to individual letter-sound associations, phonological
awareness such as blending and segmentation, verbal working
memory, and local visual analysis are specially required. In the
following educational stages, with repeated exposure to words,
the functioning of the phonological working memory becomes
automated and children reach automatic recognition of the
words, as a whole visual stimulus, and a strong activation of
long-term memory stores is now required in order to support
the reading (Nicolson and Fawcett, 1990;Pennington, 2006;
Menghini et al., 2010a,b;Ruffino et al., 2014;Gori and Facoetti,
2015).
From a neurobiological point of view, different brain networks
are involved in these different phases. According to Pugh et al.
(2001), the dorsal brain circuits is at first engaged and performs
the analytic processing necessary for learning to integrate
orthographic with phonological and lexical–semantic features
of words. Gradually, the ventral circuit attends to the reading
process, in the word form system, underlying fluency in word
recognition. A distinction between a ventral-lexical pathway and
a dorsal-sublexical pathway has been confirmed also in several
functional and structural studies (Pugh et al., 2000;Jobard
et al., 2003;Borowsky et al., 2006, 2007;Steinbrink et al., 2008;
Friederici et al., 2009).
Among the cognitive factors involved in reading, the present
study aimed at better clarifying specific contribution of visual-
spatial abilities in affecting reading skills of children with DD
at different educational stages. In DD, reading deficits related
to visual-spatial processing could be associated more in the
first educational years to deficits in local analysis required
for exploring letters and words, while a deficit in the global
perceptual processing could affect more the following years when
words should be analyzed for their global shapes. Difficulties
in global perceptual processes could similarly affect the first
educational stages since high-frequency words could be analyzed
even in the first stages as a whole stimulus.
Frontiers in Psychology | www.frontiersin.org 2December 2016 | Volume 7 | Article 1997
fpsyg-07-01997 December 19, 2016 Time: 12:27 # 3
Giovagnoli et al. Visual-Spatial Abilities in Children with Developmental Dyslexia
In order to explore the relationship between reading and
visual-spatial abilities at different educational stages, participants
were divided into two subgroups (younger and older) depending
on whether they attended primary or secondary school. If the
first educational stage involves both the analytic process for
reading a new word and the more global process for recognizing
already met words, while the next educational stage mainly needs
more global process for reading already met words, then the
contribution of visual-spatial deficits in reading of children with
DD should vary across reading stages.
Our predictions were the following: first, we should observe
that younger children with DD show poor performances in
visual-spatial tasks elaborated by both dorsal and ventral
pathway, while older children with DD show poor performances
in more global visual perceptual tasks mainly processed by ventral
pathway. Second, if different visual-spatial abilities are involved
in reading process according to different educational stages, then
reading performances should be predicted by distinct visual-
spatial measures. Particularly, we should observe that reading
in younger children is primarily predicted by both dorsal and
ventral visual-spatial abilities while in older children by more
ventral visual-spatial abilities.
MATERIALS AND METHODS
Participants
Sixty right-handed children with DD (M/F =33/27; mean
age ±standard deviation =11.4 ±1.9, range =8.4–17.6)
and sixty-five NR (M/F =37/28; mean age ±standard
deviation =11.9 ±1.8, range =8.1–15.7) participated in
the study. Participants were recruited also for previous studies
(Menghini et al., 2011;Varvara et al., 2014). The clinical
diagnosis of DD was made on the basis of the DSM-IV criteria
(American Psychiatric Association [APA], 2000) and national
recommendations (Consensus Conference, 2007). Children with
DD showed reading speed or accuracy level at least 2 standard
deviations below the mean of their chronological age. Speed (in
seconds) and errors were measured using the age-standardized
“Battery for the evaluation of Developmental Dyslexia and
Dysorthographia” (Sartori et al., 2007). NR performed within
1 standard deviation from the mean in reading tasks (speed
and accuracy) and were matched to the children with DD for
chronological age and cognitive abilities (see Table 1). Criteria for
inclusion in the study were the following: a normal or corrected
to normal visual acuity; and no other significant co-morbidity,
like attention deficit or hyperactivity disorder (ADHD). The
diagnosis of ADHD in the group with DD and in the control
group was assessed on the basis of the ADHD rating scale
for parents (Conners, 2000), as well as a clinical examination
according to DSM-IV criteria. Afterward, we split participants
into two subgroups based on different education stages and
in accordance with previous studies using a similar cut-off
(Biancarosa and Snow, 2006;Wexler et al., 2012).
The first subgroup included children with DD and NR
attending the primary school, with a chronological age under
11 years old (younger) (respectively, N=28 and N=22). Since
TABLE 1 | Chronological age, cognitive and reading measures of younger
and older subgroups of children.
DD NR
Mean (SD) Mean (SD)
Younger
Age (years) 9.78 (0.74) 10.09 (1.04)
CPM (percentile) 54.8 (26.4) 55.77 (25.4)
Word reading
Speed (z-score) −2.5 (2.76) 0.52 (0.72)
Accuracy (z-score) −2.9 (2.11) 0.22 (0.45)
Word Inefficiency Index 237.5 (129.6) 92.63 (23.6)
Non-word reading
Speed (z-score) −1.73 (1.89) 0.11 (0.84)
Accuracy (z-score) −2.47 (1.29) 0.18 (0.68)
Non-word Inefficiency Index 186.6 (89.8) 82.8 (25.33)
Older
Age (years) 12.86 (1.36) 12.89 (1.27)
CPM (percentile) 71.59 (21.85) 67.28 (25.52)
Word reading
Speed (z-score) −3.90 (3.23) 0.43 (0.58)
Accuracy (z-score) −4.13 (3.41) 0.04 (0.61)
Word Inefficiency Index 155.68 (73.69) 63.53 (15.79)
Non-word reading
Speed (z-score) −3.24 (2.06) 0.43 (0.84)
Accuracy (z-score) −2.65 (2.17) 0.31 (0.56)
Non-word Inefficiency Index 136.9 (59.83) 50.74 (14.47)
DD, Developmental Dyslexia; NR, Normal Readers; SD, Standard Deviation; CPM,
Colored Progressive Matrices.
at the end of primary school fluent and automatic reading is
generally expected to be achieved (Schwanenflugel et al., 2006),
the second subgroups included children and adolescents with DD
and NR in the secondary school, with a chronological age equal
or above 11 years old (older) (respectively, N=32 and N=43).
Chronological age, cognitive abilities, and measures of reading
abilities of subgroups are reported in Table 1. In both the younger
and the older subgroups, participants with DD did not differ
from NR in chronological age (younger DD vs. younger NR:
t(48)= −1.25, p=0.22; older DD vs. older NR: t(73)= −0.86,
p=0.93) and in cognitive abilities, as measured by Colored
Progressive Matrices (CPM; Raven, 2010): younger DD vs.
younger NR: t(48)=0.22, p=0.98; older DD vs. older NR:
t(73)=0.79, p=0.43.
Children with DD were tested at the Children’s Hospital
Bambino Gesù (Rome, Italy) while NR were evaluated
individually in their school. Children were evaluated in
two sessions on different days with each session lasting
approximately 1 h and a half. Cognitive abilities and reading
abilities were assessed in the first session while the remaining
tasks were administered in the other sessions, in a pseudorandom
way. A description of the tests is provided below.
Ethics Statement
Before testing children, we obtained informed consent from all
participants and their families, and the agreement by the local
ethical committee (Protocol Number 486LB). Informed consent
Frontiers in Psychology | www.frontiersin.org 3December 2016 | Volume 7 | Article 1997
fpsyg-07-01997 December 19, 2016 Time: 12:27 # 4
Giovagnoli et al. Visual-Spatial Abilities in Children with Developmental Dyslexia
was given by the parents as well as the children. All children
and families were informed through an information sheet, read
to participant’s parents prior to asking their consent, with a
copy handed to them to take home, and a separate sheet on
which to record consent. Information about the project was
explicitly written on the consent form, either in bullet points
or as extended text. The name and signature of the person
who took the participants through the consent procedure was
recorded. The privacy of participants was guaranteed according
to the data protection law. The study involved children with
developmental reading disorder. Informed consent was given
by parents and children. Children and families could withdraw
their participation at any time in the study. Test administrators
received intensive and specific training. Children were assessed
in an encouraging and child-oriented manner.
Design and Materials
Measures obtained by the participants in each task were
transformed into z-scores to perform statistical analyses. The
mean and the standard deviation were based on normative data
of the tasks, except for SRT and STICK, in which the normative
data were not available, and the mean and standard deviation of
NR were used.
Cognitive Abilities
General intelligence was evaluated by CPM (Raven, 2010) and the
scores were expressed in percentiles.
Reading Abilities
Speed and accuracy of reading were assessed using two subtests
from the “Battery for the evaluation of Developmental Dyslexia
and Dysorthography” (Sartori et al., 2007). In the first subtest,
participants had to read aloud 4 lists of 28 concrete and abstract,
high or low frequency words (length from 4 to 8 letters). In
the second task children had to read three lists of 16 non-
words (length from 5 to 9 letters). Speed (in seconds) and errors
(each incorrect word or non-word was calculated as one error)
were computed for each task and standardized using mean and
standard deviation according to the class. An inefficiency reading
index was devised to take into account both reading speed and
accuracy and was separately computed for words and non-words.
Each index was calculated as follows: the ratio between word or
non-word reading speed (in seconds) and accuracy rate (number
of correct words or non-words by the total number of words or
non-words). Mean and standard deviation of word and non-word
inefficiency index were included in Table 1.
Visual-Spatial Tasks
The visual-spatial perception abilities were evaluated using the
subtests 2 and 4 from the Visual Perception Test (VPT; Hammill
et al., 1994). VPT2, Visual Perception Test-subtest 2 is a
visual-spatial ability task designed to investigate perceptual and
discrimination capacities in the visual domain. Participants were
asked to match one figure to another from a multiple-choice
display consisting of an array of vertically arranged figures. In
each of the 25 items, the wrong alternatives differed from the
target due to minor changes in orientation or spatial relations
between constitutive elements. VPT4, Visual Perception Test-
subtest 4, measures the ability to distinguish an object from the
background or from surrounding objects. Children were asked
to identify the parts that one complex figure was made of. In
more detail, participants were required to do a visual-object
recognition, identifying two or more figures among other line
drawings in a confusing context or within overlapping images.
Visual-spatial imagery and mental rotation abilities were
evaluated using the Spatial Rotation Test (SRT; Vicari et al., 2006)
and the Stick (STICK; Carlesimo et al., 2001). In each trial of SRT,
children had to mentally rotate geometric figures to find the target
among five alternatives drawn on a sheet of paper. In each trial of
STICK, participants were presented with a line drawing of an L-
or an S-shaped stick with a full or an empty circle at the two ends.
They had to indicate which of four similarly shaped sticks, rotated
from 45 to 270◦on a horizontal plane, would match the stimulus
stick after appropriate mental rotation based on the respective
location of the full and the empty circles.
Selective visual-spatial attention was assessed using a subtest
of the Test of Everyday Attention for Children (Map Mission,
MAP; Manly et al., 2002). In this subtest, participants were
presented with a color-printed A3-laminated city map, with
eighty targets representing restaurants (i.e., small knife and
fork symbols) randomly distributed across the map. Distracting
symbols of the same size, such as supermarket trolleys, cups,
or cars, were also present. Participants used a pen to circle as
many targets as possible in 1 min. The performance score was
calculated by the number of target symbols correctly marked by
the participants.
Integration of visual input and motor output was measured
using the Visual Motor Integration Test (VMI; Beery and
Buktenica, 2000). Children were asked to copy geometric shapes
on a sheet of paper. Overall scores were given by a qualitative
evaluation of drawings, according to specific criteria.
For demonstrative purpose, means, standard deviation and
raw score ranges for each visual-spatial measure were included
in Table 2.
Statistical Analysis
Statistical analyses were performed using z-scores (see Design
and Materials). In order to investigate if there were any
differences in performing visual-spatial tasks according to
educational stages, a MANOVA analysis was performed with
Group (DD vs. NR) and Subgroup (younger vs. older) as
between-subject factors and Task (STICK vs. MAP vs. SRT vs.
VPT2 vs. VPT4 vs. VMI) as within-subject factors.
Pairwise comparisons between each group were analyzed
through LSD post hoc tests.
To determine whether reading abilities were predicted by
visual-spatial measures, a stepwise regression analysis in each
subgroup (younger and older), with children with DD and NR
as a whole group, was performed.
Two different regression analyses were computed with the
inefficiency reading index (for words and non-words, separately)
as dependent variable and all the visual-spatial measures (MAP,
SRT, STICK, VPT2, VPT4, and VMI) as independent variable.
For each analysis, the statistical criterion for entry was a
Frontiers in Psychology | www.frontiersin.org 4December 2016 | Volume 7 | Article 1997
fpsyg-07-01997 December 19, 2016 Time: 12:27 # 5
Giovagnoli et al. Visual-Spatial Abilities in Children with Developmental Dyslexia
TABLE 2 | Raw score range, mean, and standard deviation for each
visual-spatial measure of younger and older subgroups of children.
Raw score DD NR
Range Mean (SD) Mean (SD)
Younger
MAP 0–80 31.32 (8.27) 33.59 (7.55)
SRT 0–27 17.82 (5.71) 20.18 (3.59)
STICK 0–10 6.25 (1.97) 7.23 (2.36)
VPT2 0–25 20.11 (4.01) 22.36 (2.95)
VPT4 0–18 13.11 (2.42) 15 (1.38)
VMI 0–27 16.32 (2.54) 20.73 (3.61)
Older
MAP 0–80 42.25 (9.48) 49.19 (9.77)
SRT 0–27 21.03 (3.14) 22.47 (2.59)
STICK 0–10 8 (1.95) 8.21 (2.01)
VPT2 0–25 22.22 (3.53) 23.33 (1.94)
VPT4 0–18 13.84 (3.31) 15.53 (2.04)
VMI 0–27 19.78 (3.05) 21.37 (2.96)
DD, Developmental Dyslexia; SD, Standard Deviation; MAP, Map Mission; SRT,
Spatial Rotation Test; STICK, Stick Test; VPT2, Visual Perception Test-subtest 2;
VPT4, Visual Perception Test-subtest 4; VMI, Visual Motor Integration Task.
probability of p≤0.05, with the criterion for subsequent removal
probability of p≥0.1. A p-value less than 0.05 was considered as
statistically significant.
RESULTS
Differences in Visual-Spatial Abilities
between DD and NR According to
Educational Stages
Results of the MANOVA (Group ×Task ×Subgroup) showed a
significant effect of Group (F(1,121)=25.31, p<0.00001), with
higher scores for NR than for children with DD, a significant
effect of Task (F(5,605)=28.63, p<0.0001) and a significant effect
of Subgroup (F(1,121)=10.87, p=0.001). The Group ×Task
effect and the Group ×Subgroup effect were found non-
significant (respectively, F(5,605)=1.98, p=0.08; F(1,121 )=0.68,
p=0.41), while the effect Subgroup ×Task resulted statistically
significant (F(5,605)=7.66, p<0.00001). A significant effect
Group ×Task ×Subgroup was also found (F(5,605)=3.01,
p=0.01).
Post hoc analysis revealed that the younger subgroup of
children with DD performed significantly worse than younger
NR in SRT (p=0.0032), in both visual perception tasks
(VPT2 p=0.040 and VPT4 p=0.017) and in VMI
(p=0.000004). No significant difference was found between
younger children with DD and NR in MAP (p=0.86) and STICK
(p=0.08).
However, older subgroup of children with DD performed
significantly worse than older NR in MAP (p=0.002), SRT
(p=0.029), and VPT4 (p=0.0022). No significant difference
was found between older children with DD and NR in STICK
(p=0.64), VPT2 (p=0.17), and VMI (p=0.07).
FIGURE 1 | Effect Group ×Task ×Subgroup of the MANOVA with
means and standard errors of each visual-spatial measure in younger
(A) and older (B) subgroups of children. DD, Developmental Dyslexia; NR,
Normal Readers; MAP, Map Mission; SRT, Spatial Rotation Test; STICK, Stick
Test; VPT2, Visual Perception Test-subtest 2; VPT4, Visual Perception
Test-subtest 4; VMI, Visual Motor Integration Task. ∗indicates p<0.05.
Figure 1 showed the effect Group ×Task ×Subgroup and
Panel A reports means and standard errors of each visual-
spatial task in younger subgroups of children with DD and NR,
while Panel B reports those of each visual-spatial task in older
subgroups of children with DD and NR.
Post hoc analysis revealed that older children with DD
performed significantly better than younger children with
DD in SRT (p=0.00001), VPT2 (p=0.04), and STICK
(p=0.0005), while no differences have been detected between
younger children with DD and older children with DD in VPT4
(p=0.56), VMI (p=0.056), MAP (p=0.61). Conversely,
older NR scored significantly higher than younger NR in
SRT (p=0.002) and MAP (p=0.01). In VMI, older NR
performed significantly worse than younger NR (p=0.004).
No differences were found between older NR and younger
NR in VPT4 (p=0.46), VPT2 (p=0.34), and STICK
(p=0.06).
Frontiers in Psychology | www.frontiersin.org 5December 2016 | Volume 7 | Article 1997
fpsyg-07-01997 December 19, 2016 Time: 12:27 # 6
Giovagnoli et al. Visual-Spatial Abilities in Children with Developmental Dyslexia
FIGURE 2 | Regression graph for word and non-word inefficiency
index in younger (A) and older (B) subgroups of children. VPT4, Visual
Perception Test-subtest 4; VMI, Visual Motor Integration Task.
Predictors of Reading Abilities in
Younger and Older Participants
In order to verify whether visual-spatial measures could be
potential predictors of reading abilities, a regression analysis was
separately performed for younger and older children. A stepwise
method, in which the word and non-word inefficiency index was
entered as the dependent variable and visual-spatial measures as
the independent variables, was applied. In younger participants,
results showed that VMI significantly predict word and non-word
inefficiency reading index accounted, respectively, for 16.3%
(F(1,48)=9.36, p=0.004) and for 15.0% (F(1,48)=8.44,
p=0.006) of the variance. Figure 2A illustrates the relation
between word and non-word inefficiency index and VMI in
younger children. In older participants, VPT4 was found as a
significant predictor of word and non-word inefficiency reading
index. In detail, VPT4 accounted for the 14.6% of the variance
(F(1,73)=12.43, p=0.001) of word inefficiency reading index
and for the 12.5% (F(1,73)=10.46, p=0.002) of non-word
inefficiency reading index. Figure 2B illustrates the relation
between word and non-word inefficiency index and VPT4 in
older children. Table 3 illustrates detailed results of the regression
analysis.
DISCUSSION
The main aim of the present study was to investigate differences
in visual-spatial abilities in children with DD compared to age-
matched NR in two different educational stages. Regression
analyses were also performed to verify whether different visual-
spatial abilities are involved in reading process according to
different educational stages.
Results revealed that younger children with DD performed
significantly worse than NR in a mental rotation task (SRT),
a more-local visual-spatial task (VPT2), a more-global visual-
perceptual task (VPT4) and a visual-motor integration task
(VMI). Our findings are similar to those found in the study
by Rüsseler et al. (2005), where younger children with DD,
compared to NR, were impaired in solving three mental rotation
tasks and the Embedded Figures Test, a test assessing the
ability to detect hidden figures in complex patterns comparable
to our VPT4. However, in another study (Del Giudice et al.,
2000) investigating visual-spatial cognition and memory in 43
children (aged 8–9 years) with reading impairments, participants
with DD did not differ from children that received a diagnosis
of DD and then recovered reading deficits at 1-year follow-
up (control group) in the visual-spatial task adopted. Since
children without any history of reading disability were included
as a control group in our study, we clearly differentiated
visual-spatial processes of children with DD from those of
NR with respect to the study by Del Giudice et al. (2000),
in which the control group comprised children had recovered
reading deficits. Therefore, we believe our results are more
informative regarding the contribution of visual-spatial abilities
in DD.
Moreover, our results documented deficits in several visual-
spatial abilities in the younger subgroup with DD, as shown by
different tasks (i.e., SRT, VPT2, VPT4, and VMI), that could
contribute to negatively affect reading skills in children with
DD at the first educational stage. Many studies investigated
the relationship between VMI and the quality of handwriting
(see, for example, Karlsdottir and Stefansson, 2002;Kaiser
et al., 2009). Since dysgraphia is known to be associated with
DD, low scores in VMI in our younger participants might
reflect poorer skills and/or less experience in handwriting.
Further studies are needed to better investigate the relationship
between visual-motor integration difficulties, poor handwriting
and reading disorders at different educational stages. However,
deficits found in VPT2 and in VMI were not documented in
the older subgroup with DD, which, in turn, showed deficits in
the more-global visual-perceptual task (VPT4), in the mental
rotation task (SRT) and in the visual attention task (MAP).
Post hoc comparison between younger and older children with
DD showed that the younger subgroup with DD obtained
significantly lower scores than the older subgroup in VPT2,
STICK and SRT while no difference emerged in VPT4, MAP,
and VMI.
Frontiers in Psychology | www.frontiersin.org 6December 2016 | Volume 7 | Article 1997
fpsyg-07-01997 December 19, 2016 Time: 12:27 # 7
Giovagnoli et al. Visual-Spatial Abilities in Children with Developmental Dyslexia
TABLE 3 | Results of stepwise regression analyses in younger and older participants.
Word Inefficiency Index Non-word Inefficiency Index
βt p βt p
Younger
MAP −0.027 −0.197 0.844 −0.006 −0.043 0.966
SRT −0.032 −0.232 0.818 0.018 0.131 0.896
STICK −0.009 0.060 0.953 −0.015 −0.104 0.918
VPT2 −0.077 −0.538 0.593 −0.066 −0.457 0.650
VPT4 −0.103 −0.766 0.448 −0.074 −0.541 0.591
VMI −0.404 −3.060 0.004∗−0.387 −2.907 0.006∗
Older
MAP −0.209 −1.881 0.064 −0.171 −1.508 0.136
SRT −0.047 −0.401 0.689 −0.061 −0.518 0.606
STICK 0.027 0.242 0.809 0.026 0.235 0.815
VPT2 0.033 0.282 0.779 0.052 0.443 0.659
VPT4 −0.381 −3.526 0.001∗−0.354 −3.235 0.002∗
VMI −0.137 −1.247 0.216 −0.110 −0.985 0.328
MAP, Map Mission; SRT, Spatial Rotation Test; STICK, Stick Test; VPT2, Visual Perception Test-subtest 2; VPT4, Visual Perception Test-subtest 4; VMI, Visual Motor
Integration Task. ∗indicates p <0.01.
Results from previous studies using rotation tasks in children
with DD aged, similarly to our older subgroup, between 11–
13 years (Corballis et al., 1985) and 10–12 years (Wang and
Yang, 2011) failed to find differences between DD and NR.
A possible explanation for this discrepant result from our study
could be found in the characteristics of the tasks to evaluate
mental rotation. Indeed, when the rotation tasks were presented
as computer games, no deficits were found in participants with
DD (Corballis et al., 1985;Wang and Yang, 2011) while when
it was used a paper and pencil task, more similar to the one
adopted in our study, a deficit in mental rotation abilities was
found in students with DD (Winner et al., 2001). Concerning
the present findings on visual attention in older children with
DD, deficits have been repetitively described in literature using
psychophysical experiments. Specifically, results evidenced in
DD reduced visual-attention span in task requiring to process
multiple elements in parallel (Bosse and Valdois, 2003;Bosse
et al., 2007;Bosse and Valdois, 2009;Lobier et al., 2014;Lobier
and Valdois, 2015). This visual processing deficit has been
interpreted as strictly connected to the reading impairment due
to the limitation of the ability of the visual-attention window to
spread over a whole word, and then to identify words with fast
and parallel procedures. As regards to VMI task, in the older
subgroup with DD, our results are consistent with those reported
by Goldstand et al. (2005), that failed to find differences in visual
processing between NR and children with DD.
The regression analyses of our study documented that in
younger participants, independently of the group (children with
DD or NR), VMI significantly predicted word and non-word
inefficiency reading index. However, in older participants, the
only significant predictor of word and non-word inefficiency
reading index was VPT4. VMI is a task designed to investigate
visual perceptive abilities and the ability to use visual information
to guide motor behavior, referred to as visual-motor integration,
and it substantially includes a wide range of abilities as visual-
spatial perceptive abilities, fine motor abilities and motor
planning. The visual-spatial perceptive abilities required by VMI
include both the analysis of the spatial location, orientation
and the visual-object recognition to perceive the global form
of the figure. A possible interpretation of the regression results
concerning VMI measures and reading deficits is that during
the first educational stage, more complex and extensive visual-
spatial abilities could be required for reading. Neuroanatomically,
when children are in the first educational stage, there is a strict
connection between the dorsal and ventral stream, and the
angular and supramarginal gyri seem to help the ventral regions
to focus on individual letters in order to identify them and their
order (Stein, 2014).
On the other hand, in our older children only the visual-
perceptual task VPT4 significantly predicted reading measures.
To solve VPT4, the form recognition of the figure is required,
regardless of changes in the surrounding environment and
the primary involvement of the ventral stream is expected
(Hebart and Hesselmann, 2012). Even if speculatively, we could
hypothesize that in this later educational stage the contribution
of visual-spatial abilities to reading relates to a more global
perception strategy to analyze the shape of the word. Indeed,
as the children grow-up, they become more expert in reading
and apply a whole recognition strategy to identify a word.
Accordingly, the ventral word form area (VWFA), located in the
fusiform gyrus, seemed to play an important role in whole word
recognition and in the form analysis of the words (Stein, 2014),
as identified by a number of neuroimaging studies (Cohen et al.,
2000, 2002;Dehaene and Cohen, 2011). When the more expert-
reader has improved the lexicon, the VWFA rapidly recognizes
the whole strings and allocates to it the meaning (Stein, 2014).
Our results could contribute to clarify the relationship
between reading and a number of visual-spatial abilities at
Frontiers in Psychology | www.frontiersin.org 7December 2016 | Volume 7 | Article 1997
fpsyg-07-01997 December 19, 2016 Time: 12:27 # 8
Giovagnoli et al. Visual-Spatial Abilities in Children with Developmental Dyslexia
different educational stages in DD, indicating that in the
first educational stage more complex and extensive visual-
spatial deficits could interfere in exploring letters and words
while in the next educational stage more-global perceptual
deficits could hinder the reading process of children with
DD.
Studies failing to find visual-spatial deficits in children or
adults with DD did not include children at different educational
stages and tended to investigate only single aspects of the visual-
spatial domain (Corballis et al., 1985;Del Giudice et al., 2000;
White et al., 2006;Wang and Yang, 2011). However, our results
stress the importance of considering different visual-spatial
domains and different educational stages to better understanding
the relationship between reading and visual-spatial abilities in
DD.
A limitation of the study is that only cross-sectional
comparisons were performed. In order to examine the change
of the relationship between visual-spatial abilities and reading
acquisition in DD a more developmental study design, including
either cross sectional analysis or longitudinal data, should be
developed in future. Moreover, caution should be taken in
generalizing our results to other languages with a reduced
orthographic-phonological correspondence. Indeed, in languages
with less transparent orthography, reading processes could
require a different contribution of local and global visual-spatial
abilities at different educational stages. Further studies are needed
in order to extend present results to other languages.
Reading is a complex cognitive process, in which not only
phonological skills, but memory, attention, automatization and
visual-spatial skills are involved. The present study focused on
the contribution of visual-spatial abilities at different educational
stages in affecting reading. Further studies are needed in order
to consider the role of the different underlying neurocognitive
deficits in DD at different developmental stages.
AUTHOR CONTRIBUTIONS
DM, GG, and ST developed the study concept and all authors
designed the study. GG, ST performed the data collection and the
data analysis under the supervision of DM and SV. GG and ST
drafted the paper and DM and SV provided critical interpretation
of the results and revisions. All authors read and approved the
final version to be submitted.
REFERENCES
American Psychiatric Association [APA] (2000). Diagnostic and Statistical Manual
of Mental Disorders, (DSM–IV). Washington, DC: American Psychiatric
Publishing.
American Psychiatric Association [APA] (2013). Diagnostic and Statistical Manual
of Mental Disorders, (DSM–5). Washington, DC: American Psychiatric
Publishing.
Beery, K. E., and Buktenica, N. A. (2000). The Beery–Buktenica Developmental
Test of Visual–Motor Integration with Additional Tests of Visual Perception
and Motor Coordination. Firenze: Giunti O.S. Organizzazioni Speciali (Italian
Adaptation).
Biancarosa, C., and Snow, C. E. (2006). Reading next—A Vision for Action and
Research in Middle and High School Literacy:A Report to Carnegie Corporation
of New York, 2nd Edn. Washington, DC: Alliance for Excellent Education.
Boets, B., Vandermosten, M., Cornelissen, P., Wouters, J., and Ghesquière, P.
(2011). Coherent motion sensitivity and reading development in the transition
from prereading to reading stage. Child. Dev. 82, 854–869. doi: 10.1111/j.1467-
8624.2010.01527.x
Borowsky, R., Cummine, J., Owen, W. J., Friesen, C. K., Shih, F., and Sarty,
G. E. (2006). FMRI of ventral and dorsal processing streams in basic reading
processes: insular sensitivity to phonology. Brain Topogr. 18, 233–239. doi:
10.1007/s10548-006- 0001-2
Borowsky, R., Esopenko, C., Cummine, J., and Sarty, G. E. (2007). Neural
representations of visual words and objects: a functional MRI study on the
modularity of reading and object processing. Brain Topogr. 20, 89–96. doi:
10.1007/s10548-007- 0034-1
Bosse, M. L., Tainturier, M. J., and Valdois, S. (2007). Developmental dyslexia: the
visual attention span deficit hypothesis. Cognition 104, 198–230. doi: 10.1016/j.
cognition.2006.05.009
Bosse, M. L., and Valdois, S. (2003). Patterns of developmental dyslexia according
to a multi–trace memory model of reading. Curr. Psychol. Lett. 10, 1.
Bosse, M. L., and Valdois, S. (2009). Influence of the visual attention span on
child reading performance: a cross– sectional study. J. Read. Res. 32, 230–253.
doi: 10.1111/j.1467-9817.2008.01387.x
Carlesimo, G. A., Perri, R., Turriziani, P., Tomaiuolo, F., and Caltagirone, C.
(2001). Remembering what but not where: independence of spatial and visual
working memory in the human brain. Cortex 37, 457–473. doi: 10.1016/S0010-
9452(08)70591-4
Cohen, L., Dehaene, S., Naccache, L., Lehericy, S., Dehaene–Lambertz, G., Henaff,
M. A., et al. (2000). The visual word form area. Brain 123, 291. doi: 10.1093/
brain/123.2.291
Cohen, L., Lehericy, S., Chochon, F., Lemer, C., Rivaud, S., and Dehaene, S. (2002).
Language–specific tuning of visual cortex? Functional properties of the visual
word form area. Brain 125, 1054–1069. doi: 10.1093/brain/awf094
Conners, C. K. (2000). Conners’ Rating Scales–Revised technical manual. North
Tonawanda. New York, NY: Multi–Health Systems.
Consensus Conference (2007). Disturbi Evolutivi Specifici di Apprendimento.
Availableat: http://www.lineeguidads a.it/download_documentiDSA/RACCOMAN
DAZIONI_PRATICA_CLINICA_DSA2007.zip [accessed September 1, 2012].
Corballis, M. C., Macadie, L., and Beale, I. L. (1985). Mental rotation and visual
laterality in normal and reading disabled children. Cortex 21, 225–236. doi:
10.1016/S0010-9452(85)80028- 9
Dehaene, S., and Cohen, L. (2011). The unique role of the visual word form area in
reading. Trends Cogn. Sci. 15, 254–262. doi: 10.1016/j.tics.2011.04.003
Del Giudice, E., Trojano, L., Fragassi, N. A., Posteraro, S., Crisanti, A. F.,
Tanzarella, P., et al. (2000). Spatial cognition in children. II. Visuospatial
and constructional skills in developmental reading disability. Brain Dev. 22,
368–372. doi: 10.1016/S0387-7604(00)00159- 5
Ehri, L. C. (1987). Learning to read and spell words. J. Read. Behav. 19, 5–31.
Felmingham, K. L., and Jakobson, L. S. (1995). Visual and visuomotor performance
in dyslexic children. Exp. Brain Res. 106, 467–474. doi: 10.1007/BF00231069
Friederici, A. D., Michiru, M., and Bahlmann, J. (2009). The role of the posterior
temporal cortex in sentence comprehension. Neuroreport 20, 563–568. doi:
10.1097/WNR.0b013e3283297dee
Geiger, G., Cattaneo, C., Galli, R., Pozzoli, U., Lorusso, M. L., Facoetti, A., et al.
(2008). Wide and diffuse perceptual modes characterize dyslexics in vision and
audition. Perception 37, 1745–1764. doi: 10.1068/p6036
Goldstand, S., Koslowe, K. C., and Parush, S. (2005). Vision, visual–information
processing, and academic performance among seventh–grade school children: a
more significant relationship than we thought? Am. J. Occup. Ther. 59, 377–389.
doi: 10.5014/ajot.59.4.377
Goodman, K. (1970). “Reading as a psychologistic guessing game,” in Theoretical
Models and Processes of Reading, eds H. Singer and R. B. Ruddell (Newark, N.J:
International reading Association).
Gori, S., Cecchini, P., Bigoni, A., Molteni, M., and Facoetti, A. (2014).
Magnocellular– dorsal pathway and sub–lexical route in developmental
dyslexia. Front. Hum. Neurosci. 8:460. doi: 10.3389/fnhum.2014.00460
Frontiers in Psychology | www.frontiersin.org 8December 2016 | Volume 7 | Article 1997
fpsyg-07-01997 December 19, 2016 Time: 12:27 # 9
Giovagnoli et al. Visual-Spatial Abilities in Children with Developmental Dyslexia
Gori, S., and Facoetti, A. (2015). How the visual aspects can be crucial in reading
acquisition: the intriguing case of crowding and developmental dyslexia. J. Vis.
15, 8. doi: 10.1167/15.1.8
Gori, S., Mascheretti, S., Giora, E., Ronconi, L., Ruffino, M., Quadrelli, E., et al.
(2015). The DCDC2 Intron 2 deletion impairs illusorymotion perception
unveiling the selective role of magnocellular–dorsal stream in reading
(dis)ability. Cereb. Cortex 25, 1685–1695. doi: 10.1093/cercor/bhu234
Hammill, D., Pearson, N., and Voress, J. (1994). TPV. Test di Percezione Visiva e
Integrazione Visuo–motoria. Trento: Erickson. (Italian Adaptation).
Hautus, M. J., Setchell, G. J., Waldie, K. E., and Kirk, I. J. (2003). Age–related
improvements in auditory temporal resolution in reading–impaired children.
Dyslexia 9, 37–45. doi: 10.1002/dys.234
Hebart, M. N., and Hesselmann, G. (2012). What visual information is processed
in the human dorsal stream? J. Neurosci. 32, 8107–8109. doi: 10.1523/
JNEUROSCI.1462-12.2012
Jobard, G., Crivello, F., and Tzourio–Mazoyer, N. (2003). Evaluation of the dual
route theory of reading: a metanalysis of 35 neuroimaging studies. Neuroimage
20, 693–712. doi: 10.1016/S1053-8119(03)00343- 4
Kaiser, M. L., Albaret, J. M., and Doudin, P. A. (2009). Relationship between
visual-motor integration, eye-hand coordination, and quality of handwriting.
J. Occupat. Ther. Sch. Early Interv. 2, 87–95. doi: 10.1080/19411240903146228
Karlsdottir, R., and Stefansson, T. (2002). Problems in developing functional
handwriting. Percept. Mot. Skills 94, 623–662. doi: 10.2466/pms.2002.94.2.623
Kuhn, M. R., Schwanenflugel, P. J., Morris, R. D., Morrow, L. M., Woo, D. G.,
Meisinger, E. B., et al. (2006). Teaching children to be fluent and automatic
readers. J. Lit. Res. 38, 357–387. doi: 10.1207/s15548430jlr3804_1
Lobier, M., and Valdois, S. (2015). Visual attention deficits in developmental
dyslexia cannot be ascribed solely to poor reading experience. Nat. Rev.
Neurosci. 16, 225. doi: 10.1038/nrn3836-c1
Lobier, M. A., Peyrin, C., Pichat, C., Le Bas, J. F., and Valdois, S. (2014). Visual
processing of multiple elements in the dyslexic brain: evidence for a superior
parietal dysfunction. Front. Hum. Neurosci. 7, 479.
Luria, A. R. (1966). Higher Cortical Functions in Man. New York, NY: Basic.
Manly, T., Nimmo–Smith, I., Watson, P., Anderson, V., Turner, A., and Robertson,
I. H. (2002). The differential assessment of children’s attention: the test
of everyday attention for children (tea–ch), normative sample and ADHD
performance. J. Child Psychol. Psychiatry 42, 1065–1081. doi: 10.1111/1469-
7610.00806
Menghini, D., Carlesimo, G. A., Marotta, L., Finzi, A., and Vicari, S. (2010a).
Developmental dyslexia and explicit long–term memory. Dyslexia 16, 213–225.
doi: 10.1002/dys.410
Menghini, D., Finzi, A., Benassi, M., Bolzani, R., Facoetti, A., Giovagnoli, S.,
et al. (2010b). Different underlying neurocognitive deficits in developmental
dyslexia: a comparative study. Neuropsychologia 48, 863–872. doi: 10.1016/j.
neuropsychologia.2009.11.003
Menghini, D., Finzi, A., Carlesimo, G. A., and Vicari, S. (2011). Working memory
impairment in children with developmental dyslexia: is it just a phonological
deficity? Dev. Neuropsychol. 36, 199–213. doi: 10.1080/87565641.2010.
549868
Nicolson, R. I., and Fawcett, A. J. (1990). Automaticity: a new framework for
dyslexia research? Cognition 35, 159–182. doi: 10.1016/0010-0277(90)90013-A
Pennington, B. F. (2006). From single to multiple deficit models of developmental
disorders. Cognition 101, 385–413. doi: 10.1016/j.cognition.2006.04.008
Peterson, R. L., and Pennington, B. F. (2012). Developmental dyslexia. Lancet 379,
1997–2007. doi: 10.1016/S0140-6736(12)60198- 6
Peterson, R. L., and Pennington, B. F. (2015). Developmental dyslexia. Annu. Rev.
Clin. Psychol. 11, 1283–1307. doi: 10.1146/annurev-clinpsy-032814-112842
Pugh, K. R., Mencl, W. E., Jenner, A. R., Katz, L., Frost, S. J., Lee, J. R., et al.
(2000). Functional neuroimaging studies of reading and reading disability
(developmental dyslexia). Ment. Retard. Dev. Disabil. Res. Rev. 6, 207–213.
doi: 10.1002/1098-2779(2000)6:3< 207::AID-MRDD8>3.3.CO;2-G
Pugh, K. R., Mencl, W. E., Jenner, A. R., Katz, L., Frost, S. J., Lee, J. R., et al. (2001).
Neurobiological studies of reading and reading disability. J. Commun. Disord.
34, 479–492. doi: 10.1016/S0021-9924(01)00060- 0
Ramus, F., Rosen, S., Dakin, S. C., Day, B. L., Castellone, J. M., White, S., et al.
(2003). Theories of developmental dyslexia: insights from a multiple case study
of dyslexic adults. Brain 126, 841–865. doi: 10.1093/brain/awg076
Raven, J. C. (2010). CPM, Coloured Progressive Matrices, series A, AB, B. Firenze:
Giunti O.S. Organizzazioni Speciali. (Italian Adaptation).
Ruffino, M., Gori, S., Boccardi, D., Molteni, M., and Facoetti, A. (2014). Spatial and
temporal attention in developmental dyslexia. Front. Hum. Neurosci. 22:331.
Rüsseler, J., Scholz, J., Jordan, K., and Quaiser–Pohl, C. (2005). Mental rotation of
letters, pictures, and three–dimensional objects in German dyslexic children.
Child. Neuropsychology 11, 497–512. doi: 10.1080/09297040490920168
Sartori, G., Job, R., and Tressoldi, P. E. (2007). Batteria per la Valutazione
Della Dislessia e Della Disortografia Evolutiva, 2nd Edn. Firenze: Giunti O.S.
Organizzazioni Speciali.
Schwanenflugel, P. J., Meisinger, E. B., Wisenbaker, J. M., Kuhn, M. R., Strauss,
G. P., and Morris, R. D. (2006). Becoming a fluent and automatic reader in the
early elementary school years. Read. Res. Qt. 41, 496–522. doi: 10.1598/RRQ.41.
4.4
Shaywitz, S. E., and Shaywitz, B. A. (2005). Dyslexia specific reading disability. Biol.
Psychiatry 57, 1301–1309. doi: 10.1016/j.biopsych.2005.01.043
Snowling, M. J. (2000). Dyslexia: a Cognitive–Developmental Perspective, 2nd Edn.
Oxford: Blackwell.
Stein, J. (2014). Dyslexia: the role of vision and visual attention. Curr. Dev. Disord.
Rep. 1, 267–280. doi: 10.1007/s40474-014- 0030-6
Steinbrink, C., Vogt, K., Kastrup, A., Müller, H. P., Juengling, F. D., Kassubek, J.,
et al. (2008). The contribution of white and gray matter differences to
developmental dyslexia: insights from DTI and VBM at 3.0 T.Neuropsychologia
46, 3170–3178. doi: 10.1016/j.neuropsychologia.2008.07.015
Swan, D., and Goswami, U. (1997). Phonological awareness deficits in
developmental dyslexia. J. Res. Read 11, 67–85.
Talcott, J., Hansen, P., Willis–Owen, C., McKinnell, I., Richardson, A., and Stein, J.
(1998). Visual magnocellular impairment in adult develop–mental dyslexics.
Neuro Ophthalmol. 20, 187–201.
Talcott, J. B., Hansen, P. C., Assoku, E. L., and Stein, J. F. (2000). Visual motion
sensitivity in dyslexia: evidence for temporal and energy integration deficits.
Neuropsychologia 7, 935–943. doi: 10.1016/S0028-3932(00)00020- 8
Varvara, P., Varuzza, C., Sorrentino, A. C., Vicari, S., and Menghini, D. (2014).
Executive functions in developmental dyslexia. Front. Hum. Neurosci. 8:120.
doi: 10.3389/fnhum.2014.00120
Vernon, M. D. (1957). Backwardness in Reading. Cambridge: Cambridge
University Press.
Vicari, S., Bellucci, S., and Carlesimo, G. A. (2006). Evidence from two genetic
syndromes for the independence of spatial and visual working memory. Dev.
Med. Child Neurol. 48, 126–131. doi: 10.1017/S0012162206000272
Vidyasagar, T. R., and Pammer, K. (2010). Dyslexia: a deficit in visuo–spatial
attention, not in phonological processing. Trends Cogn. Sci. 14, 57–63. doi:
10.1016/j.tics.2009.12.003
von Károlyi, C., Winner, E., Gray, W., and Sherman, G. F. (2003). Dyslexia linked
to talent: global visual–spatial ability. Brain Lang. 85, 427–431. doi: 10.1016/
S0093-934X(03)00052- X
Wang, L. C., and Yang, H. M. (2011). The comparison of the visuo–spatial abilities
of dyslexic and normal students in Taiwan and Hong Kong. Res. Dev. Disabil.
32, 1052–1057. doi: 10.1016/j.ridd.2011.01.028
Wexler, J., Vaughn, S., Edmonds, M., and Reutebuch, C. K. (2012). A synthesis of
fluency interventions for secondary struggling readers. Read. Writ. 21, 317–347.
doi: 10.1007/s11145-007- 9085-7
White, S., Milne, E., Rosen, S., Hansen, P., Swettenham, J., Frith, U., et al.
(2006). The role of sensorimotor impairments in dyslexia: a multiple case
study of dyslexic children. Dev. Sci. 9, 237–255. doi: 10.1111/j.1467-7687.2006.
00483.x
Winner, E., von Károlyi, C., Malinsky, D., French, L., Seliger, C., Ross, E., et al.
(2001). Dyslexia and visual–spatial talents: compensation vs. deficit model.
Brain Lang. 76, 81–110. doi: 10.1006/brln.2000.2392
Conflict of Interest Statement: The authors declare that the research was
conducted in the absence of any commercial or financial relationships that could
be construed as a potential conflict of interest.
Copyright © 2016 Giovagnoli, Vicari, Tomassetti and Menghini. This is an open-
access article distributed under the terms of the Creative Commons Attribution
License (CC BY). The use, distribution or reproduction in other forums is permitted,
provided the original author(s) or licensor are credited and that the original
publication in this journal is cited, in accordance with accepted academic practice.
No use, distribution or reproduction is permitted which does not comply with these
terms.
Frontiers in Psychology | www.frontiersin.org 9December 2016 | Volume 7 | Article 1997
Available via license: CC BY 4.0
Content may be subject to copyright.
Content uploaded by Deny Menghini
Author content
All content in this area was uploaded by Deny Menghini on Dec 22, 2016
Content may be subject to copyright.
Content uploaded by Deny Menghini
Author content
All content in this area was uploaded by Deny Menghini on Dec 22, 2016
Content may be subject to copyright.
