Brain and Cognition 57 (2005) 8–15
www.elsevier.com/locate/b&c

Dysgraphia in two forms of conduction aphasia
Venu Balasubramanian
Speech–Language Pathology and Audiology, School of Graduate Medical Education, Seton Hall University, South Orange, NJ, United States
Accepted 12 August 2004
Available online 11 November 2004

Abstract
Recent clinical observations, in the absence of experimental data, appear to suggest that written expression in conduction aphasics parallels their speech (Goodglass, 1992). The current study undertakes an analysis of word level writing in two conduction aphasics, and attempts to explore the posited ÔparallelÕ relationship between speech production deficits and deficits in written expression.
JL, a 66-year-old female with left posterior parietal lobe lesion and PP, a 65-year-old female with a left posterior temporo-parietal
lobe lesion served as subjects of this study. Their response patterns on Boston Naming Test (BNT) and written naming task (John
Hopkins Dysgraphia Battery) were utilized to verify the parallel hypothesis. Although both cases have exhibited phonological and
semantic paraphasias on BNT, PPÕs overall performance was far superior to that of JL. JL produced numerous multiple responses to
stimuli compared to PPÕs occasional multiple responses. PPÕs performance on the written naming task was far inferior to that of JL.
JLÕs predominant error pattern in writing was the production of phonologically similar words to the target words. This paper argues
that such seemingly contradictory, unpredicted patterns can be parsimoniously better explained, not by the parallel hypothesis but
by current cognitive-neuropsychological models of writing.
Ó 2004 Elsevier Inc. All rights reserved.

1. Introduction
WernickeÕs, 1874 initial neuro-anatomical model of
language representation suggested that an interruption
of the fiber tract that is deep to the insular cortex that
connects the center for acoustic images of speech and
the motor center for speech production could result in
a disconnection syndrome of aphasia. Wernicke predicted that such a syndrome would be characterized by
fluent speech, good auditory comprehension but poor
verbal repetition for auditorily presented speech. In
the subsequent years, Wernike reported two cases that
matched his predictions and named the syndrome as
Ôconduction aphasia.Õ However, Wernicke did not offer
post-mortem confirmation of site of lesion in either case.
Over the decades that followed WernikeÕs conceptualization of conduction aphasia, this syndrome has evolved
far beyond the limits of its original characterization.

E-mail address: balasuve@shu.edu.
0278-2626/$ - see front matter Ó 2004 Elsevier Inc. All rights reserved.
doi:10.1016/j.bandc.2004.08.012

This metamorphosis of conduction aphasia can be seen
in changes in the areas of (1) lesion sites, (2) core symptom characteristics, and (3) classification of conduction
aphasia, and the underlying mechanism responsible for
the symptoms.
The issue of site of lesion associated with conduction
aphasia remained elusive and problematic to the Wernicke–Lichtheim–Geschwind model of language. GeschwindÕs (1970) account of conduction aphasia argues that
the lesions typically occur in the arcuate fasciculus beneath the lower parietal lobe to disconnect the WernickeÕs area from BrocaÕs area. Once again, focal
lesion occurring in the arcuate fasciculus in such cases
has not been documented at autopsy. Furthermore, lesion studies on conduction aphasia have identified lesions in a number of different areas including the
posterior portion of the superior temporal gyrus, supramarginal gyrus, angular gyrus or insular cortex of the
left hemisphere (Anderson et al., 1999; Green & Howes,
1978). It is also perplexing to note that frontal lobe lesion was reported in a case with conduction aphasia

V. Balasubramanian / Brain and Cognition 57 (2005) 8–15

(Sherrmata, Andrews, & Pandya, 1974). Cases of conduction aphasia without lesions in the arcuate fasciculus
have also been reported (Damasio & Damasio, 1980).
More recent studies identified two predominant patterns
of lesions: (1) posterior superior temporal gyrus, and (2)
inferior parietal lobe of the left hemisphere (Axer, von
Keyserlingk, Berks, & von Keyserlingk, 2001; Bartha
& Benke, 2003). A few conduction aphasics were reported with more extensive lesions involving temporal
and parietal lobes of the left hemisphere (Axer et al.,
2001). The role of the posterior superior temporal gyrus
in speech production was further confirmed by recent
functional neuroimaging studies (Hickok, Erhard, Kassubek, Helms-Tillery, & Naeve-Velguth, 2000) and stimulation studies (Quigg & Fountain, 1999).Thus, the role
of the arcuate fasciculus lesion in producing conduction
aphasia appears to be attenuated by increasing number
of studies that identified lesions in the posterior superior
temporal lobe or inferior parietal lobe of the left
hemisphere.
Another dimension of development of the concept of
conduction aphasia syndrome pertains to the core symptoms with which it has been associated. The original
conceptualization of conduction aphasia as a disconnection syndrome only predicted a core deficit of repetition
in the absence of auditory comprehension impairments
or speech production deficits (Wernicke, 1874). WernickeÕs reasoning was based on the assumption that
the center for auditory language (memory for acoustic
images of words) and BrocaÕs areas are essentially intact
when the lesion occurs only in the fiber tract that interconnects these two language related cortical centers.
However, WernickeÕs two cases of conduction aphasia
had an additional symptom of altered sound patterns
of the target words, known as, literal or phonemic paraphasias. Both repetition deficits and literal or phonemic
paraphasias have been reported in several studies on
conduction aphasia. For the diagnostic identification
of conduction aphasia, at least for some researchers,
repetition deficit was not the defining characteristic.
Phonemic paraphasia is the major indispensable feature
of conduction aphasia (Goodglass, 1992). This particular view differs from WernickeÕs disconnection theory
of conduction aphasia that predicted the occurrence of
repetition deficit as the central feature. Other researchers
observed that each of these two symptoms may characterize different type of conduction aphasia (Shallice &
Warrington, 1977).
From a historical perspective, it is interesting to note
that conduction aphasia that was conceptualized as a
unitary syndrome came to be further sub-divided in
more than one way. The homogeneity of the syndrome
of conduction aphasia was supported by some researchers (Bartha & Benke, 2003; Goodglass, 1992), whereas,
heterogeneity of this syndrome received support from
others (Axer et al., 2001; Caplan, Vanier, & Baker,

9

1986; Caplan & Waters, 1992; Caramazza, Basili, Koller, & Berndt, 1991; Demeurisse & Capon, 1991; Hillis
& Caramazza, 1989; Kohn, 1992; Nadeau, 2001; Roeltgen, 1994, 2000; Shallice & Warrington, 1977). A classification of conduction aphasia that was based on the
two symptoms of repetition deficits and phonemic paraphasias was introduced by Shallice and Warrington
(1977) and was further elaborated by other researchers
(Caplan et al., 1986; Nadeau, 2001), is as follows: (1)
repetition conduction aphasia, and (2) reproduction
conduction aphasia. Repetition conduction aphasia
was characterized by failure to repeat verbal stimuli
due to auditory short-term memory impairment. In such
cases, spontaneous speech was said to be unaffected. In
reproduction conduction aphasia, it was proposed that
the problem in repetition was due to a deficit in encoding phonological form of words and the associated
sequential articulatory gestures. Axer et al. (2001) identified two types of conduction aphasias on the basis of
lesion sites: (1) suprasylvian and (2) infrasylvian conduction aphasias. Axer et al. (2001) claim that these two
forms are actually equivalent to reproduction and repetition conduction aphasias, respectively. The performance of suprasylvian conduction aphasics on
auditory comprehension and repetition tasks was found
to be better than that of the infrasylvian conduction
aphasics. However, the incidence of phonemic paraphasias was much higher in suprasylvian conduction aphasics than in infrasylvian group. These researchers also
report that lesions extending to both infra- and suprasylvian regions of the left hemisphere produced symptoms
of both types. In addition, the mixed groupÕs performance was found much inferior to that of the other
two groups on tasks related to writing, naming, and
comprehension (Axer et al., 2001).
Studies on conduction aphasia, as summarized
above, have largely targeted phonemic paraphasias
and repetition deficits. There were very few studies that
looked at other modalities of language performance,
such as auditory language comprehension (Caramazza
& Zurif, 1976; Zurif & Caramazza, 1976), and written
expression (Axer et al., 2001; Goodglass, 1992; Marcie
& Hecaen, 1979). But, what is quite conspicuous in the
literature on conduction aphasia is the lack of comprehensive, theoretically motivated studies on graphic performance of conduction aphasics. There are a few
clinical observations on the occurrence of spelling errors. For instance, Roeltgen (1985) summarizes the clinical observations of other researchers (Marcie &
Hecaen, 1979) thus: ‘‘Agraphia with conduction aphasia
is characterized by misspelling and overwriting’’ (p. 78).
Such errors were said to parallel the phonological production errors in conduction aphasics (Goodglass,
1992). In sum, only the modality of verbal language production in conduction aphasics was subjected to sophisticated cognitive neuropsychological and neurolinguistic

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V. Balasubramanian / Brain and Cognition 57 (2005) 8–15

investigations. Although, most proponents of cognitive
neuropsychological approach have strong reservations
about the existence of aphasia syndromes (Caramazza,
1984; Schwartz, 1984) the application of cognitive neuropsychological methods in the study of aphasia syndromes such as BrocaÕs aphasia, WernickeÕs aphasia,
and conduction aphasia continue to take place. Thus,
the use of cognitive neuropsychological methods in the
study of dysgraphia in conduction aphasia is entirely
justifiable. Comprehensive, model oriented studies of
written production in conduction aphasia still remain
to be undertaken. The current study offers empirical
data and argues for the expansion of the syndromic features of conduction aphasia to include types of deficits
in written production.
GoodglassÕ (1992) observation about the parallels between the phonological production deficits and dysgraphia characteristics in conduction aphasia deserves
further exploration, especially, in the context of recent
developments in cognitive neuropsychological studies
of dysgraphia and the models of writing that prompted
and benefited from such studies. The Ôparallel deficitÕ
view appears to be based on the assumption that writing
requires phonological mediation. Contrary to this
assumption, current research in cognitive neuropsychology supports the autonomy of lexical orthography (Miceli, Benvegnu, Capasso, & Caramazza, 1997; Rapp,
Benzing, & Caramazza, 1997). There is a robust body
of clinical literature that supports the autonomous or
semi-autonomous status of lexical orthography (Basso,
Taborelli, & Vignola, 1978; Hier & Mohr, 1977; Miceli
et al., 1997). Selective impairment or preservation of lexical orthography has been reiterated in these studies.
Contemporary account of the cognitive architecture of
spelling recognizes (1) lexical, (2) post-lexical, and (3)
sub-lexical processes (Rapp, 2002; Rapcsak & Beeson,
2002). These processes can be selectively impaired in
brain damaged cases. Models of word level writing in response to dictation, written naming of pictures, and
copy encoding explain spelling performance in terms
of these processes and their components.
The objectives of the current study are (1) to undertake an analysis of word level writing in two participants
with conduction aphasia, and (2) to verify the claim that
there are parallels between phonological production errors and writing errors in conduction aphasics.

stroke and subsequently developed symptoms of conduction aphasia (see Fig. 1, BDAE profile of JL). She
had exhibited an urge to self-correct her production errors (conduit dÕapproache). Phonemic and semantic
paraphasias were the predominant characteristics of
speech production.
At 2 years post-onset, JL was tested on Boston Diagnostic Aphasia Examination (Goodglass & Kaplan,
1983). As JLÕs BDAE profile (Fig. 1) indicates, her auditory and reading comprehension performance was much
better than her verbal performance as revealed by her
patterns of errors on measures of fluency, naming, repetition, and paraphasias. She had also produced neologistic responses on confrontation naming and
repetition tasks. JL underwent CT scan examination
twice in her course of stay at a hospital. According to
the medical report, the second CT scan examination
done 2 weeks post-onset revealed a resolving cortical
infarction in the posterior temporo-parietal lobe (see
Fig. 3). In addition, there was bilateral white matter
atrophy of the cortex.
PP, a 65-year-old Caucasian female suffered an ischemic stroke. According to her medical report, a CT scan
examination revealed a lesion in the left temporal-parietal regions (see Fig. 4). However, PPÕs lesion in the left
temporo-parietal cortex was more extensive than that
of JL. Additionally, PPÕs brain did not evidence bilateral
white matter atrophy. PP had fluent aphasic symptoms
at 2 weeks post-onset. At 3 years post-onset, PP was
tested on Boston Diagnostic Aphasia Examination and
her performance was suggestive of patterns of conduction aphasia (see Fig. 2). PPÕs auditory comprehension
was much better than her performance on verbal tasks
as revealed in her fluency, repetition, and paraphasia
raw scores and percentiles.
A comparison of the BDAE profiles of JL and PP
indicates the following: (1) on naming task, PPÕs performance was far superior to that of JL, (2) JL produced
greater number of paraphasias than did PP, with no
neologistic paraphasias in the verbal production of PP,
and (3) repetition was found impaired in both cases to
variable degree. At word level, PPÕs repetition was much
better than that of JL. Yet another feature that distinguishes JL from PP is the tendency exhibited by JL to
produce multiple responses to produce target words
resulting in Ôconduit dÕapproache.Õ
2.2. Materials

2. Method
2.1. Subjects
The participants of the current study were two persons with conduction aphasia in their chronic stage:
JL and PP. JL, a 66-year-old Caucasian female and a
former bank accountant suffered a non-hemorrhagic

The present study used two test batteries: (1) Boston
Naming Test (Goodglass & Kaplan, 1983), and (2) The
John Hopkins Dysgraphia Battery (Goodman &
Caramazza, 1986).
The Boston Naming Test is a test that targets picture
naming ability of subjects. It consists of 60 stimulus pictures that represent names of high, mid, and low fre-

V. Balasubramanian / Brain and Cognition 57 (2005) 8–15

11

Fig. 1. JLÕs BDAE profile.

quency of occurrence These pictures are arranged
sequentially in a descending order of frequency. Thus,
the test would prove to be increasingly more challenging
to the examinees, as the test progresses. Norms are
available only for adults of 18–59 years of age.
The Johns Hopkins University Dysgraphia Battery is
an unpublished, nonetheless popular, test among clinicians, and researchers for assessing written skills. This
battery consists of several sub-tests that assess the cognitive processes (lexical, post-lexical, and sub-lexical)
underlying graphic performance at word level. Five
sub-tests that were utilized in the present study include:
(1) concreteness, (2) parts of speech, (3) word length, (4)
written naming, and (5) copy transcoding. At this point,
there are no norms available for the experimental version of JHUDB.
2.3. Procedures
JL was tested at home. PP was tested at a University
Speech–Language and Hearing Clinic. Boston Naming
Test and The John Hopkins University Dysgraphia Battery (JHUDB) were administered over 10 sessions. Both

subjects were encouraged to let the examiner know when
they needed a break. First, the Boston Naming Test was
administered to both subjects, followed by the JHUDB.
In administering the Boston Naming Test (BNT) the
following procedures were used. For each stimulus picture, when a subject fails to give any response, a stimulus cue was given to facilitate the naming process. If the
stimulus cue (semantic in nature) did not facilitate the
production of target name, a phonemic cue in the form
of the initial sound of the target name was given. A subjectÕs score on Boston Naming Test will include the
number of spontaneously given correct responses plus
the number of correct responses following phonemic
cues. The maximum possible score on BNT is 60. Paraphasic responses (literal, neologistic, and verbal) were
also identified.
Three of the five sub-tests of JHUDB involved writing to dictation (concreteness sub-test, parts of speech
sub-test, and word length sub-test). The copy transcoding sub-test involved copying the target words. The written naming task required production of written names
for stimulus pictures. Responses to all target words in
each sub-test were graded either correct or incorrect.

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V. Balasubramanian / Brain and Cognition 57 (2005) 8–15

Fig. 2. PPÕs BDAE profile.

A correct written response is one without errors. Each
correct response was given one point, and incorrect ones
were given a zero point. Maximum possible scores for
each of the JHUDB sub-test are as follow: concreteness
sub-test (42), part of speech sub-test (138), word length
sub-test (70) written naming (51), copy transcoding (62),
and phoneme–grapheme conversion list (110).

3. Results and discussion
JLÕs performance on BNT indicated that she produced 17 correct responses, 13 of those were spontaneously correct, and four responses followed the
phonemic cues. In other words, JL performed at

28.3% accuracy level in naming a total of 60 pictures.
Error analysis of JLÕs responses revealed that she produced multiple responses for 20 target stimuli. These responses were mostly in the form of phonological
approximates to the target names. Thus, they constitute
what is known as conduit dÕapproache. In her multiple
attempts to produce the target names, JL also produced
names that were semantically related to the target. JL
also produced neologistic jargons in response to the picture naming task. These features are unique to JL.
PPÕs performance on BNT was far superior to that of
JL. The total number of correct responses was 48, 41 of
those responses were spontaneously correctly produced
and the remaining seven were produced following phonemic cuing. Thus, PP performed at 80% accuracy level

V. Balasubramanian / Brain and Cognition 57 (2005) 8–15

Fig. 3. JLÕs CT scans indicate lesion in the left posterior parietal lobe.

Fig. 4. PPÕs CT scans indicate lesion in the left temporo-parietal lobes.

in naming a total of 60 pictures of BNT. Her error patterns included both phonemic and semantic paraphasias. In the process of picture naming, PP received
fewer stimulus cues and phonemic cues than did JL.
Both PP and JL produced phonemic (literal) paraphasias, verbal paraphasias, and neologistic responses
on BDAE tasks (see Figs. 1 and 2). The BNT task added
more information about their verbal speech characteris-

13

tics. JLÕs conduction aphasia is of Ôconduit dÕapproacheÕ
type, whereas PP evidenced conduction aphasia without
such a tendency to produce multiple responses to each
stimulus. Besides, BDAE and BNT profiles suggest that
PPÕs performance on all speech related tasks was superior to that of JL.
According to Goodglass (1992), dysgrphia in conduction aphasia will parallel their speech characteristics.
One may predict that JLÕs graphic performance will be
parallel to her verbal characteristics. In other words,
JLÕs written production will be far more seriously impaired than that of PP. One may also expect multiple responses for each stimulus on writing tasks and
phonologically related responses in written production.
On the other hand, if the lexical orthography is
autonomous and not phonologically mediated in writing, as claimed by cognitive neuropsychologists, then,
there will be no parallel deficits in writing in conduction
aphasia. These predictions can be tested by examining
the performance of both JL and PP on various sub-tests
of JHUDB.
On the sub-tests of JHUDB, JLÕs scores and percent
correct responses are as follow: (1) written naming:
37.2% (19/51), (2) word length: 30% (21/70), (3) concreteness: 19% (8/42), (4) part of speech: 17.8% (26/
138), (5) copy transcoding: 93.5% (58/62), and (6) phoneme–grapheme conversion: 43.6% (48/110).
PPÕs scores on five sub-tests of JHUDB are as follows: (1) written naming: 3.9% (2/51), (2) word length:
0% (0/70), (3) concreteness: 0% (0/42), (4) parts of
speech: 0% (0/138), (5) copy transcoding: 100% (62/
62), and (6) phoneme–grapheme conversion list: not
administered.
The patterns of performance of JL and PP on these
sub-tests of JHUDB are not in accord with the predictions based on verbal characteristics that were uncovered by BNT and BDAE. PPÕs written production was
profoundly impaired in all sub-tests of JHUDB, except
copy transcoding sub-test. On the other hand, JLÕs performance showed moderate–severe impairment on five
out of six sub-tests of JHUDB. In contradistinction to
the predictions made above, JLÕs performance is actually
better than that of PP on these sub-tests, except the copy
transcoding sub-test. These results are puzzling and confusing to the adherents of the neoclassical localizationists. In order to shed more light on the nature of
dysgraphia in these two forms of conduction aphasia,
an error analysis of responses given to written naming
task was undertaken (see Figs. 5A and B).
Error responses were classified following the categories of errors described in the JHUDB. The categories
include (1) phonologically plausible errors (PPE), (2)
phonologically implausible non-words (PINs), (3) donÕt
know (DK), (4) semantic errors (SEMANTIC), (5) visually/phonologically similar words (VSW), (6) semantic/
visually similar, (7) partial responses, and (8) other/mis-

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V. Balasubramanian / Brain and Cognition 57 (2005) 8–15

offer support to the ÔparallelÕ view, whereas data obtained from JL appear to offer some support to the parallel view. However, JLÕs data can be explained in terms
of the impaired modular cognitive processes such as the
lexical, post-lexical, and sub-lexical processes.
It is also important to recognize that PP with temporo-parietal lesion has experienced greater problems in
writing. This finding accords well with previous studies
that reported severe problems in writing (Axer et al.,
2001).
Lastly, the present study offers data that appear to
warrant a revision of the symptom complex of conduction aphasia syndrome to reflect on the characteristics
of dysgraphia noted in JL and PP. However, before a
decision is made in favor of syndrome expansion, more
case studies need to be carried out to fully explore the
dysgraphia characteristics in conduction aphasics. In
the current study, important tasks such as oral spelling
could not be carried out because both JL and PP were
unavailable for further testing. As reviewed in Section
1 of this paper, the syndrome of Ôconduction aphasiaÕ
has undergone revisions before and it is hard to say that
this syndrome will not undergo further modification in
future.

Acknowledgments
Fig. 5. (A and B) Present error patterns in written performance of JL
and PP, respectively.

cellaneous responses (see Figs. 5A and B). A closer look
at the error patterns bring out some of the commonalities and differences between JL and PP in their performance on written confrontation naming task
(JHUDB). In JLÕs written production errors, the visually/phonologically similar word responses (VSW) was
the major error category accounting for nearly 35% of
her errors on this particular task. PPÕs error patterns included large number of partial responses that included
the first letter of the target word and graphemes that
are not part of the target word. PP also produced many
more phonologically implausible non-words than did
JL. Both JL and PP produced nearly same number of
semantically related errors. Yet another unique feature
of PPÕs written error production was the complete absence of the category called Ôphonologically plausible errorsÕ (PPE). Thus, PPÕs written naming is more seriously
impaired than JLÕs. The absence of PPE category of error, large number of PIN and partial responses attest to
this observation. However, it seems that both JL and PP
are impaired, to varying degrees, in lexical, post-lexical,
and sub-lexical processes of writing.
The present study explored the clinical observation
that writing errors parallel the verbal production errors
in conduction aphasia. Data obtained from PP do not

I would like to thank the anonymous reviewers for
their constructive criticisms and suggestions for the
improvement of the form and content of the manuscript.

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