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Neurocase: The Neural Basis of Cognition
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Differential Reorganization of Fusiform Gyrus in Two
Types of Alexia after Stroke
a

b

b

Sung-Bom Pyun , Hyo-Jeong Sohn , Jae-Bum Jung & Kichun Nam

b

a

Korea University Medical Center, Korea University College of Medicine, Physical Medicine
and Rehabilitation , Seoul, Republic of Korea
b

Korea University College of Liberal Arts, Psychology , Seoul, Republic of Korea
Published online: 25 Aug 2010.

To cite this article: Sung-Bom Pyun , Hyo-Jeong Sohn , Jae-Bum Jung & Kichun Nam (2008) Differential Reorganization
of Fusiform Gyrus in Two Types of Alexia after Stroke, Neurocase: The Neural Basis of Cognition, 13:5-6, 417-425, DOI:
10.1080/13554790701881715
To link to this article: http://dx.doi.org/10.1080/13554790701881715

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Neurocase (2007) 13, 417–425
http://www.psypress.com/neurocase
ISSN: 1355-4794 print / 1465-3656 online
DOI: 10.1080/13554790701881715

Differential Reorganization of Fusiform Gyrus in Two Types
of Alexia after Stroke
NNCS

SUNG-BOM PYUN1, HYO-JEONG SOHN2, JAE-BUM JUNG2 and KICHUN NAM2
Reorganization of Fusiform Gyrus in Alexia

1

Downloaded by [University of Regina] at 07:52 17 November 2014

Korea University Medical Center, Korea University College of Medicine, Physical Medicine and Rehabilitation, Seoul,
Republic of Korea
2
Korea University College of Liberal Arts, Psychology, Seoul, Republic of Korea

Lesions affecting the left fusiform gyrus (FG) commonly result in dyslexia and recovery largely depends on efficient
reorganization of the reading network. We performed a follow-up fMRI study to elucidate the reorganization patterns of the FG
according to the recovery of reading ability in two patients (MH with pure alexia and KM with alexia with agraphia) after stroke
involving the left FG. Initially, MH was an effortful letter-by-letter (LBL) reader, and she improved to become a proficient LBL
reader. The initial fMRI results showed scattered activation on occipital and ventral temporal cortex during reading, which was
localized to right FG in the follow-up study. KM’s severe alexia with agraphia did not improve, even after 6 months had passed
since the onset of the alexia. The initial and follow-up fMRI results showed no significant activation in the bilateral FG or central
higher language areas during word reading. Our results suggest that the reorganization of the FG is different according to the type
of alexia and the amount of clinical recovery in each patient. Also, the successful reorganization of the visual component of
reading in the right FG is responsible for the recovery of LBL reading in pure alexia.

Keywords: Pure alexia; Alexia with agraphia; Fusiform gyrus; Visual word form area; Functional MRI.

Introduction
The acquisition of literacy depends on the development
of elaborate links between vision and language, between
letter strings and sounds, and between letter strings and
lexical entries in the memory system. To develop reading
efficiency, a word-form recognition system must be used
to allow for the rapid identification of visual words across
a wide variety of irrelevant parameters, such as position,
size, color, font or case. Such a word-form recognition
system is called a visual word form (Warrington & Shallice
1980). Recent functional neuroimaging studies have
provided considerable insight into the neural networks
associated with written word processing. These studies
were primarily focused on showing the patterns of activation in the left mid-fusiform gyrus that is associated with
various reading paradigms. Cohen and colleagues (Cohen
2000; McCandliss, Cohen, & Dehaene 2003) proposed
the visual word-form area (VWFA; Talairach coordinates,

x = −43, y = −54, z = −12) which is located in Brodmann’s
cortical area 37 (BA 37) within the left occipitotemporal
sulcus bordering the fusiform gyrus (FG). Meta-analysis
(Bolger, Perfetti, & Schneider 2005) of the results of
neuroimaging studies of word reading suggested that the
writing systems utilize a common network of regions
when processing words in English and other Western
European languages, Chinese and Japanese Kana. The VWFA
showed consistent localization in a variety of tasks and
writing systems. However, few studies have reported the
direct comparison of the patterns of activation when reading
Hangul and Western languages. The alphabetic system of
Hangul is quite different from that of Western and other
East Asian languages. The arrangement of consonants
and vowels is not linear, and their combination makes a
syllable within the space of a square-like block that
resembles the shape of Chinese characters. Thus, each
character in Hangul can be regarded as a syllabogram. For
example, ‘
’ is a two-syllable Korean word that means

This work was supported by the Korea Science and Engineering Foundation (KOSEF) grant funded by the Korean government
(MOST) (R01-2006-000-10733-0).
Address correspondence to S.-B. Pyun, Korea University Medical Center, Korea University College of Medicine, Physical Medicine
and Rehabilitation, 5-Ga 126-1, Anam-Dong, Sungbuk-Gu, Seoul 136-705, Republic of Korea. E-mail: rmpyun@korea.ac.kr
© 2007 Psychology Press, an imprint of the Taylor & Francis Group, an Informa business

Downloaded by [University of Regina] at 07:52 17 November 2014

418 S.-B. PYUN ET AL.
‘Korea’, and can be decomposed into consonants and
vowels,
. An
fMRI study suggested that reading Hangul appears to
corroborate with that of alphabetic words at the general
level (Yoon, Cho, Chung, & Park 2005).
Alexia is a syndrome characterized by a deficit in reading
without deficits in spoken language or auditory comprehension. Patients with alexia can be classified as having
peripheral or central alexia, depending on whether they
are associated with a misperception of words or a disturbance of higher language processing (Warrington &
Shallice 1980). The ability to read can be improved in
patients with alexia. As it is associated with natural
recovery, the application of dyslexia rehabilitation may
facilitate the reorganization of reading networks during
the recovery process (Adair et al. 2000; Beeson,
Magloire, & Robey 2005; Maher et al. 1998). Since
Dejerine described two distinct types of alexia: alexia
with agraphia following a lesion in the left angular
gyrus (AG) and pure alexia due to infarction of the
occipital gyrus and splenium of the corpus callosum,
recent neuroimaging studies provided converging evidence of the functional importance of the FG in various
subtypes of pure alexia (Cohen et al. 2004a; Henry
2005; Marsh & Hillis 2005). Furthermore, the mechanisms of letter-by-letter (LBL) reading and its improvement are thought to result from the selective and
successful shift of the visual component of reading to
the right hemisphere, particularly to the homologue of
the VWFA (Cohen et al. 2004a; Henry et al. 2005). One
study (Adair et al. 2000) measured regional cerebral
blood flow (CBF) before and after therapy in a patient
with acquired phonologic dyslexia after infarction
involving the temporal and inferior parietal lobe. After
treatment, nonword reading led to increased CBF in the
right posterior perisylvian cortices and bilateral Broca’s
area, and a modest increase in CBF was also detected in
the posterior half of the right temporal lobe, including
BA 37. The reorganization of the reading network after
alexia is a dynamic process, and the patterns by which
this occurs may be quite different depending on the lesion
site, type of alexia and the clinical course of recovery.
However, there is insufficient functional neuroimaging
data in other types of alexia, and further research is
needed in order to understand the role of the right FG in
alexia with or without agraphia. In addition, functional
neuroimaging studies on the processes involved in reading
the Korean writing system, Hangul, are scarce, and
alexia patients who were native Korean speakers have
not been studied.
We designed this study in order to elucidate the differential reorganization patterns, especially in the fusiform
gyrus (FG), in two patients with pure alexia and alexia
with agraphia after stroke involving the left FG using a
follow-up fMRI study.

Methods
We performed an fMRI study at 1 month after the onset of
stroke in two patients and followed up 7 months (MH) and
5 months (KM) later. Informed consent to the procedures
was obtained from each participant, and the Health Service
Human Research Ethics Committee and the Committee on
Experimental Procedures Involving Human Subjects of the
Asan Medical Center approved this study.

Case MH
MH was a 56-year-old woman and she had been working
as a dyer. Her native language was Korean and she did not
know any other languages. She had received 12 total years
of education and right hand laterality quotient examined by
Edinburgh handedness inventory (EHI) (Oldfield 1971)
was 100%. After an attack of spontaneous intracerebral
hemorrhage in the temporoparietal area (Figure 1A), she
could not discriminate between colors (achromatopsia) nor
read any syllables or words. A visual field examination
(HFA II, Humphrey®, Germany) revealed right homonymous hemianopsia. Her initial symptoms of global alexia

Fig. 1. (A) Brain CT of MH showing intracerebral hemorrhage
in the left parietal and temporal region. (B) Diffusion-weighted
brain MRI of KM shows extensive cerebral infarction involving
the left ventral temporal cortex and parietal lobe.

REORGANIZATION OF FUSIFORM GYRUS IN ALEXIA
gradually improved, and 1 month after the onset she was
able to read Korean words laboriously through the LBL
reading strategy. She participated in a daily class for an
illiterate until the follow-up fMRI study.

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Case KM
KM was a right-handed 59-year-old woman and she was
a homemaker. She had received 12 total years of education and right hand laterality quotient was 100%. Her
native language was Korean and she could not speak any
other languages. She visited an emergency room (ER)
due to severe headache and visual disturbance that had
lasted for 2 days. Several hours after visiting the ER, she
developed a language comprehension deficit without
expressive difficulty, and she could not read any written
words or numerals. There was no noticeable motor weakness
in all four extremities. A visual field examination revealed
right homonymous hemianopsia. After workup she was
diagnosed as having an infarction in the left ventral temporal and parietal cortex due to Moyamoya disease, and
the diamox SPECT revealed markedly decreased metabolism
in the left occipito-temporo-parietal cortex (Figure 1B).
She was discharged from the hospital 1 week later, but
her symptoms of global alexia persisted throughout this
study.
Language and behavioral test
We evaluated cognitive function with the Mini-Mental
Status Examination (MMSE), and attention (auditory
and visual continuous performance test) and memory
(verbal and visual learning test) function were assessed
with the computerized neuropsychological test (CNT,
Max Medica, Seoul, South Korea). Language function
including writing and reading ability was assessed with
the Korean version of the Western Aphasia Battery
(K-WAB) (Kertesz 1984). Also we examined four
additional online tasks-same letter matching, picture
naming, picture-word matching, and lexical decision
tasks (LDT)-programmed in SuperLab 2.0 software
(Cedrus, USA).

419

objects covertly and we made the black line drawings
with shadings for this study (Figure 2A). The rate of
stimulus presentation was one stimulus per every 3 s. We
presented total number of 40 custom drawing of living
and non-living objects as stimulus pictures and same
images were used during initial and follow up fMRI studies.
During the control block, the participants performed
covert speech, saying a meaningless Korean phrase
‘
(mu–mu)’, when non-nameable custom drawing
of geometrical figures were displayed (Figure 2B).
Formation of second word reading session was similar to
previous session and it consisted of 4 word reading and
5 control blocks. Participants were instructed to read presented Korean words covertly during the reading block
(Figure 2C). We presented total number of 40 words, 2–4
syllables in length, and same number of high and low
frequency words were included. In the control block,
participants were instructed to say ‘mu-mu’ covertly
when non-readable Arabic words were displayed (Figure 2D).
Before the fMRI study, we trained two participants
repeatedly to speak covertly using sample tasks of each
session.
The blood-oxygenation-level-dependent (BOLD) fMRI
measurement, which employs the echo planar imaging
(EPI) technique, was performed using a 1.5T MR scanner
(CV I, GE, USA) with a standard head coil. For the anatomic base images, 20 T1-weighted axial conventional
spin echo images (5 mm thick) were obtained with a
matrix size of 256 × 256 pixels and a field of view of
240 mm parallel to the anterior–posterior commissure.
The EPI images were acquired over the same 20 slices
for each epoch. The imaging parameters for each
experiment were TR/TE = 3 s/30 ms, FOV = 240 mm,

Functional MRI
We used a block design, including picture naming, word
reading and control trial blocks, over two sessions, to
subtract the areas activated by simple visual input and
oromotor movement from activation during picture naming and reading words. The first session consisted of
4 picture naming and 5 control blocks per session beginning with a control block (30 s per block, total 270 s).
During the picture naming block, participants were
instructed to report the name of a presented drawing of

Fig. 2. Examples of the task for fMRI study. Drawings in upper
row are stimuli for picture naming session, picture naming (A),
control task (B). Lower row is word stimuli for word reading
session, Korean word (C) and control task written by Arabian
(D). All the tasks were performed using covert speech.

Downloaded by [University of Regina] at 07:52 17 November 2014

420 S.-B. PYUN ET AL.
matrix = 64 × 64 pixels, slice thickness = 5 mm, and flip
angle = 80°. The fMRI data were analyzed using SPM-II
software (Wellcome Department of Cognitive Neurology, London, UK) implemented in the MATLAB program (Mathworks, Inc., Sherborn, MA, USA). The EPI
images were spatially h, poroducing a toalt of 780 images
for enique, was perforealigned to the first image for head
motion, and the images were co-registered with the
patient’s structural T1 image. Afterward, the images were
smoothed using an 8mm FWHM Gaussian kernel, and normalization was not performed. Statistical parametric maps
were obtained, and voxels were considered significant at
an uncorrected threshold of p < .0001.
The activation patterns of occipitotemporal cortex and
FG were compared between initial and follow up studies
using each patient’s personal T2* weighted images. For
each participant, a general linear test (GLT) contrasting
activity associated with follow up study with that associated
with initial was performed. All the voxels were considered
in the subtraction and were identified as significantly
activated if they passed a height threshold set at uncorrected p < .0001.

Results

on the LDT. Seven months later, her MMSE improved to
25 points. The results of the attention tests were normal,
but her performance remained low on the verbal learning
test in the areas of registration and delayed recall. Her
aphasia improved to the normal range, except for mild
anomia, and she achieved proficiency in the LBL reading
skill. Her performance on the other neuropsychological
tests also improved to a near normal range (Table 1).
Case KM
Her initial MMSE score was 19 points, and the auditory
attention and verbal-learning test results were below the
reference values. The results of the K-WAB showed good
verbal language function, but she could not read any
words or sentences, and she had difficulty writing (alexia
with agraphia). In the neuropsychological online tests,
she was able to match letters fairly well, but she could not
discriminate between consonants and vowels. At the time
of the follow-up evaluation, her K-WAB score showed
improvement in the aphasia profiles. Her reading and
writing inabilities persisted and she could hardly read
single syllables, such as her last name. Other neuropsychological tests showed no remarkable improvement in
comparison to the initial evaluations (Table 1).

Behavioral results

fMRI results

Case MH
At that time of initial study, her MMSE score was 18
out of 30 possible points and she scored below the 5th
percentile on the auditory and visual attention and memory
tests. Neuropsychological test revealed very low performance

Case MH
Activations in serial fMRI studies of two participants
were summarized in Table 2. During picture naming, the
initial fMRI showed activation in the right occipitotemporal junction and FG and the follow-up fMRI showed

Table 1. Results of neurobehavioral tests in cases MH and KM
MH

KM

Test

Initial

Follow-up

Initial

Follow-up

MMSE (30)
K-WAB (AQ; 100)
Spontaneous speech (20)
Auditory comprehension (200)
Repetition (100)
Naming (100)
Reading word or sentence (100)
Writing (100)
Neuropsychological language tests
Same-letter matching (60)
Picture naming (80)
Picture–word matching (98)
Lexical decision task (80)

18
68.8
16
123
71
51
27
76

25
91.2
19
197
82
85
74
81

15
58.0
15
57
76
35
6
18

19
81.8
18
145
84
72
24
23

58
36
85
29

60
64
93
–*

51
25
65
45

58
40
68
35

Numbers in parenthesis are the highest score for each test.
MMSE, Mini-Mental Status Examination; K-WAB, Korean version of the Western Aphasia Battery; AQ, aphasia quotient.
*MH did not complete the follow-up lexical decision task.

REORGANIZATION OF FUSIFORM GYRUS IN ALEXIA

421

Table 2. Results of activation in initial and follow-up fMRI in two patients with alexia
Initial study

Follow-up study

Coordinates

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Region

Cluster

Case MH
Picture naming > control
L PCG
462
R OG, FG
460
R SMA
37
R PCG
30
L OG
27
L Thm
25
Word reading > control
L IFG
1038
L PCG
420
L OG
290
R IFG
119
R MFG
91
R MTG
57
R AG
44
L AG
25
Case KM
Picture naming > control
R OG
58
Word reading > control
R AG
70
R STG
65
R MFG
32
R Cbll
24

Coordinates

x

y

z

T

Region

Cluster

x

y

z

T

−42
27
7
48
−19
0

−4
−71
11
−8
−55
0

43
−30
32
29
18
2

9.93
10.34
4.71
5.71
5.26
4.40

R OTG
L PCG
R SMA

129
33
31

27
−38
3

−69
−9
−1

−24
42
47

7.86
7.10
5.88

−44
−38
−12
56
41
59
22
−23

16
−8
−48
15
46
−1
−47
−58

10
38
−34
−5
7
−14
16
27

6.94
8.32
6.54
7.26
5.85
6.06
6.74
5.23

R MFG
R FG
L PCG
R IFG
L IFG
L STG
R SFG
R SMA

328
232
167
149
125
41
40
23

36
30
−38
51
−21
−26
6
0

54
−61
−6
42
56
−65
19
−13

11
−28
40
−8
−8
−7
28
45

7.29
9.05
7.28
7.88
7.93
7.70
5.13
4.62

23

−45

−30

5.57

R OG
R Cbll

37
28

9
13

−46
−71

−36
−19

6.17
4.04

26
53
41
11

−45
15
45
−38

25
−20
15
−35

7.19
6.41
7.88
4.86

R MTG
R AG

64
54

40
27

14
−46

−49
14

5.63
7.21

Uncorrected p < .0001, extent voxel > 20, AG, angular gyrus; Cbll, cerebellum; FG, fusiform gyrus; IFG, inferior frontal gyrus; MFG, middle
frontal gyrus; MTG, middle temporal gyrus; OG, occipital gyrus; PCG, precentral gyrus; SFG, superior frontal gyrus; SMA, supplementary motor
area; SMG, supramarginal gyrus; STG, superior temporal gyrus; Thm, thalamus.

focalization in the right occipitotemporal junction. Subtraction between two fMRI studies showed activation in
right occipitotemporal junction (x = 24, y = − 73, z = − 15;
Z = 4.36) (Figure 3A, B).
During word reading, the initial activation was
observed at the left central reading network and its right
homologous areas including bilateral inferior frontal
gyrus (IFG), AG and precentral gyrus (PCG). Also, left
occipital gyrus (OG), right middle frontal gyrus and right
middle temporal gyrus was activated. The follow-up
fMRI study showed similar activation in bilateral IFG
and focalized activation in the right lateral FG within the
ventral temporal cortex was detected. When comparing
follow up with initial study activated consistently the FG
homologous area to the VWFA (x = 32, y = − 56, z = −
25; Z = 7.72). And other areas including right superior
temporal gyrus (STG; x = 54, y = 20, z = −25; Z = 7.53),
left STG (x = −40, y = 35, z = −30; Z = 5.71) and left AG

(x = − 22, y = − 56, z = − 35; Z = 4.75) were also
activated (Figure 3C, D).
Case KM
The initial fMRI showed activation in the right occipitotemporal junction during the picture naming task and the
follow-up results showed only focal activation of right
OG. After subtraction of initial from follow up study
activated left inferior temporal gyrus (x = − 22, y = −56,
z = − 35; Z = 4.75), left PCG (x = − 23, y = − 21, z = 45;
Z = 4.01) and right OG (x = 5, y = − 43, z = − 30;
Z = 4.2). But there is no activation in the right ventral
occipitotemporal cortex which was activated in case MH
(Figure 4A, B).
During word reading, right AG, STG and middle frontal gyrus were activated and right middle temporal gyrus
and right AG showed activation in the follow up study.

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422 S.-B. PYUN ET AL.

Fig. 3. The results of fMRI study during picture naming (upper row) and word reading (lower row) in case MH with pure alexia.
The displayed brain maps connected with lines were images of direct comparison between two longitudinal scans, follow up study
minus initial study. Initial picture naming (A) activated right ventral occipitotemporal junction and the fusiform gyrus (arrow) and
follow up study (B) activated occipitotemporal gyrus (arrow). Direct comparison from follow up to initial study showed activation
in right occipitotemporal junction (thick arrow). During word reading, initial study (A) showed scattered activation in right middle
temporal gyrus, and surrounding areas of lesion in left ventral temporal cortex and no remarkable activation was detected in right
posterior fusiform gyrus (arrow). In follow up study (B) MH improved to be a proficient letter-by-letter reader and right fusiform
gyrus (arrow) homologous to visual word form area (VWFA) was activated and right VWFA was consistently activated after
subtraction from follow up study to initial study (thick arrow). To view this figure in colour, please visit the online version of this
issue.

423

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REORGANIZATION OF FUSIFORM GYRUS IN ALEXIA

Fig. 4. The fMRI results during picture naming (upper row) and word reading (lower row) after subtraction of control task in case
KM with global alexia with agraphia. The displayed brain maps connected with lines were images of direct comparison between
two longitudinal scans, follow up study minus initial study. Initial (A) and follow up (B) picture naming task showed right occipital
gyrus. Direct comparison between two studies activated left inferior temporal gyrus, left precentral gyrus and right occipital gyrus.
Initial word reading task (C) activated anterior portion of right temporal lobe and follow up study (D) revealed no remarkable
activation in bilateral fusiform gyri. Direct comparison of serial studies showed activation in right occipital gyrus, left middle
frontal gyrus (x = − 47, y = − 27, z = 25; Z = 7.53) and left precentral gyrus. To view this figure in colour, please visit the online
version of this issue.

424 S.-B. PYUN ET AL.
There was no significant activation in the ventral temporal cortex or areas representing left language network.
Subtraction from follow up to initial study showed activation in right OG (x = 22, y = − 53, z = 15; Z = 4.2),
left middle frontal gyrus (x = − 47, y = − 27, z = 25;
Z = 7.53) and left PCG (x = −23, y = − 36, z = − 40,
Z = 4.23). There was no activation in right FG which was
typically activated in case MH (Figure 4C, D).

Downloaded by [University of Regina] at 07:52 17 November 2014

Discussion
Cohen and colleagues (Cohen 2000; Dehaene, Le Clec,
Poline, Le Bihan, & Cohen 2002) have labeled the most
posterior part of BA 37 within the left OT sulcus bordering
the FG as the VWFA. In their proposed visual processing
model, during the early retinotopic processing of words
the right and left hemispheric visual inputs processed
hierarchically from V1 to V2 and V4 (Cohen et al. 2003).
These visual inputs project to the VWFA in the left fusiform, and the right visual cortex conveys the inputs to the
VWFA through the splenium of the corpus callosum.
Many studies have supported the presence of a VWFA,
but the existence and functional specialization of the
VWFA is still under debate (Devlin, Jamison, Gonnerman,
& Matthews 2006; Hillis et al. 2005; McCandliss et al.
2003; Price & Devlin 2003; Price, Winterburn, Giraud,
Moore, & Noppeney 2003). Many neuroimaging results
reported consistent activation of VWFA in response
to reading words within and across writing systems and
languages (Bolger et al. 2005). There are no known
studies reporting the direct comparison of activation
patterns between unique Korean writing system ‘Hangul’
and Western languages while reading. In an fMRI
study (Yoon et al. 2005), Korean word reading activated
bilateral FG, left middle frontal gyrus, left superior temporal gyrus, right mid temporal gyrus, precentral gyrus
and insula and the results were similar to other writing
systems.
Lesions affecting the ventral temporal cortex, including
the FG, commonly result in selective reading impairment
without difficulties in identifying single letters, which
makes LBL reading possible. In our two cases of alexia,
though they had a similar location of cortical damage in
the left FG and parietal cortex, the type and degree of
impairment in their reading abilities and their recovery
courses were quite different. MH achieved a good level
of LBL reading skill, but KM did not recover from severe
alexia, even after 6 months had passed since the onset of
alexia. Our fMRI results suggested that the two cases
developed different courses of functional reorganization
during reading. Compared to the picture naming task,
MH’s initial fMRI results during reading showed scattered activations of the bilateral lingual gyrus and left
ventral temporal cortex. Seven months later, however, the

activations had transferred to the right posterior FG,
including the so-called VWFA. These results support the
results of previous reports (Cohen et al. 2004a, 2004b;
Henry et al. 2005) that the clinical improvement from
an initially poor LBL reader to a proficient reader was
primarily related to a successful shift of the visual component of reading to the right hemisphere, especially to
the right FG including the VWFA. The patient’s continuous
participation in a community based learning program for
an illiterate might have facilitated the cortical networks in
the right hemisphere during the reading process (Adair
et al. 2000; Beeson et al. 2005). However, KM’s clinical
courses and reorganization patterns were quite different.
During the follow-up fMRI studies, there were no remarkable activations in the bilateral FG or central language
areas, which suggest a failure to successfully reorganize
the damaged VWFA. Many researchers argued that
global alexia was associated with damage to the ventral
temporal cortex and left posterior interhemispheric callosal
pathway, especially in the forceps major and splenium
(Binder & Mohr 1992; Cohen et al. 2003; Sakurai et al.
2000; Silver et al. 1988; Usui et al. 2003). KM’s MRI
and diamox SPECT showed damage not only to the
ventral temporal cortex, but also to the left interhemispheric callosal pathway and to the parietal cortex,
including the AG and supramarginal gyrus (SMG).
The AG is known as a multimodal integration area
working as a semantic access node and a crucial transmodal interface between auditory system and knowledge.
Also recent neuroimaging studies have indicated
that the SMG is an area related to reading through the
graphophonological conversion (GPC) route (Jobard,
Crivello, & Tzourio-Mazoyer 2003; Mesulam 1998).
Extensive damage to the inferior parietal lobule and
the FG might interrupt the reorganization processes,
and the top–down influences cannot reach the VWFA
through the preserved long distance, U-shaped association fibers and activation by auditory words, whenever
orthographic processing is required (Cohen et al. 2004a;
O’Craven & Kanwisher 2000). In addition, she did not
participate in any rehabilitation programs for alexia
and agraphia, and therefore the chance for functional
reorganization could be minimal.
In summary, our results of two patients with different types of alexia suggest that the recovery and
improvement of the LBL reading skill in pure alexia
after damage confined to the left ventral temporal
cortex largely depends on the successful shift of the
visual component of reading to the right homologue
cortex and active participation in rehabilitation programs may facilitate the reorganization processes.
However, extensive damage to the ventral temporal
cortex together with the callosal reading pathways and
higher reading center located in the inferior parietal
lobule may lead to poor recovery from global alexia

REORGANIZATION OF FUSIFORM GYRUS IN ALEXIA
and the failure to reorganize the reading networks,
including the FG.
Original manuscript received 24 July 2007
Revised manuscript accepted 16 December 2007
First published online 31 March 2008

Downloaded by [University of Regina] at 07:52 17 November 2014

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