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Behrmann, M. & Plaut, D. C. (2013). Bilateral Hemispheric Processing of
Words and Faces: Evidence from Word Impairments in Prosopagnosia and Face
Impairments in Pure Alexia. Cerebral Cortex.
Notes: Considerable research has supported the view that faces and words are
subserved by independent neural mechanisms located in the ventral visual
cortex in opposite hemispheres. On this view, right hemisphere ventral
lesions that impair face recognition (prosopagnosia) should leave word
recognition unaffected, and left hemisphere ventral lesions that impair word
recognition (pure alexia) should leave face recognition unaffected. The
current study shows that neither of these predictions was upheld. A series
of experiments characterizing speed and accuracy of word and face
recognition were conducted in 7 patients (4 pure alexic, 3 prosopagnosic)
and matched controls. Prosopagnosic patients revealed mild but reliable word
recognition deficits, and pure alexic patients demonstrated mild but
reliable face recognition deficits. The apparent comingling of face and word
mechanisms is unexpected from a domain-specific perspective, but follows
naturally as a consequence of an interactive, learning-based account in
which neural processes for both faces and words are the result of an
optimization procedure embodying specific computational principles and
constraints
Department of Psychology, Center for the Neural Basis of Cognition, Carnegie
Mellon University, Pittsburgh, PA 15213-3890, USA
Dundas, E. M., Plaut, D. C., & Behrmann, M. (2013). The joint development of
hemispheric lateralization for words and faces. Journal of Experimental
Psychology: General, 142, 348-358.
Notes: Consistent with long-standing findings from behavioral studies,
neuroimaging investigations have identified a region of the inferior
temporal cortex that, in adults, shows greater face selectivity in the right
than left hemisphere and, conversely, a region that shows greater word
selectivity in the left than right hemisphere. What has not been determined
is how this pattern of mature hemispheric specialization emerges over the
course of development. The present study examines the hemispheric
superiority for faces and words in children, young adolescents and adults in
a discrimination task in which stimuli are presented briefly in either
hemifield. Whereas adults showed the expected left and right visual field
superiority for face and word discrimination, respectively, the young
adolescents demonstrated only the right-field superiority for words and no
field superiority for faces. Although the children's overall accuracy was
lower than that of the older groups, like the young adolescents, they
exhibited a right visual field superiority for words but no field
superiority for faces. Interestingly, the emergence of face lateralization
was correlated with reading competence, measured on an independent
standardized test, after regressing out age, quantitative reasoning scores,
and face discrimination accuracy. Taken together, these findings suggest
that the hemispheric organization of face and word recognition do not
develop independently and that word lateralization, which emerges earlier,
may drive later face lateralization. A theoretical account in which
competition for visual representations unfolds over the course of
development is proposed to account for the findings. (PsycINFO Database
Record (c) 2013 APA, all rights reserved)
Department of Psychology, Carnegie Mellon University
Nestor, A., Behrmann, M., & Plaut, D. C. (2012). The Neural Basis of Visual
Word Form Processing: A Multivariate Investigation. Cerebral Cortex.
Notes: Current research on the neurobiological bases of reading points to
the privileged role of a ventral cortical network in visual word processing.
However, the properties of this network and, in particular, its selectivity
for orthographic stimuli such as words and pseudowords remain topics of
significant debate. Here, we approached this issue from a novel perspective
by applying pattern-based analyses to functional magnetic resonance imaging
data. Specifically, we examined whether, where and how, orthographic stimuli
elicit distinct patterns of activation in the human cortex. First, at the
category level, multivariate mapping found extensive sensitivity throughout
the ventral cortex for words relative to false-font strings. Secondly, at
the identity level, the multi-voxel pattern classification provided direct
evidence that different pseudowords are encoded by distinct neural patterns.
Thirdly, a comparison of pseudoword and face identification revealed that
both stimulus types exploit common neural resources within the ventral
cortical network. These results provide novel evidence regarding the
involvement of the left ventral cortex in orthographic stimulus processing
and shed light on its selectivity and discriminability profile. In
particular, our findings support the existence of sublexical orthographic
representations within the left ventral cortex while arguing for the
continuity of reading with other visual recognition skills
Center for the Neural Basis of Cognition, Carnegie Mellon University, 4400
Fifth Avenue, Pittsburgh, PA 15213, USA
Starrfelt, R. & Behrmann, M. (2011). Number reading in pure alexia-A review.
Neuropsychologia, 49, 2283-2298.
Notes: It is commonly assumed that number reading can be intact in patients
with pure alexia, and that this dissociation between letter/word recognition
and number reading strongly constrains theories of visual word processing. A
truly selective deficit in letter/word processing would strongly support the
hypothesis that there is a specialized system or area dedicated to the
processing of written words. To date, however, there has not been a
systematic review of studies investigating number reading in pure alexia and
so the status of this assumed dissociation is unclear. We review the
literature on pure alexia from 1892 to 2010, and find no well-documented
classical dissociation between intact number reading and impaired letter
identification in a patient with pure alexia. A few studies report strong
dissociations, with number reading less impaired than letter reading, but
when we apply rigorous statistical criteria to evaluate these dissociations,
the difference in performance across domains is not statistically
significant. There is a trend in many cases of pure alexia, however, for
number reading to be less affected than letter identification and word
reading. We shed new light on this asymmetry by showing that, under
conditions of brief exposure, normal participants are also better at
identifying digits than letters. We suggest that the difference observed in
some pure alexic patients may possibly reflect an amplification of this
normal difference in the processing of letters and digits, and we relate
this asymmetry to intrinsic differences between the two types of symbols
Center for Visual Cognition, Department of Psychology, Copenhagen
University, O. Farimagsgade 2A, DK-1353 Copenhagen K, Denmark
Mycroft, R. H., Behrmann, M., & Kay, J. (2009). Visuoperceptual deficits in
letter-by-letter reading? Neuropsychologia, 47, 1733-1744.
Notes: A longstanding and controversial issue concerns the underlying
mechanisms that give rise to letter-by-letter (LBL) reading: while some
researchers propose a prelexical, perceptual basis for the disorder, others
postulate a postlexical, linguistic source for the problem. To examine the
nature of the deficit underlying LBL reading, in three experiments, we
compare the performance of seven LBL readers, matched control participants
and one brain-damaged patient, OL, with no reading impairment. Experiment 1
revealed that the LBL patients were impaired, relative to the controls and
to OL, on a same/different matching task using checkerboards of black and
white squares. Given that the perceptual impairment extends beyond
abnormalities with alphanumeric stimuli, the findings are suggestive of a
more general visual processing deficit. This interpretation was confirmed in
Experiments 2 (matching words and symbol strings) and 3 (visual search of
letter and symbol targets), which compared the processing of linguistic and
non-linguistic written stimuli, matched for visual complexity. In both
experiments, the LBL patients displayed qualitatively similar effects of
length and left-to-right sequential ordering on linguistic and
non-linguistic stimuli. Moreover, there was a clear association between the
perceptual impairments on these tasks and the slope of the reading latency
function for the LBL patients. Taken together, these findings are consistent
with a significant visuoperceptual impairment in LBL that adversely affects
reading performance as well as performance on other non-reading tasks
South London and Maudsley NHS Trust, UK
Leff,
A. P. & Behrmann, M. (2008). Treatment of reading impairment after stroke.
Current Opinion in Neurology, 21, 644-648.
Notes: PURPOSE OF REVIEW: Reading impairments after left or right hemisphere
stroke are common yet receive little attention from clinicians and
therapists. In this review, we focus on the classification of acquired
alexia and the current theory and practice underlying the rehabilitation of
this diverse set of disorders. RECENT FINDINGS: The underlying behavioural
impairments that dictate reading ability in the acquired alexias are
becoming better understood; this, in turn, has led to targeted therapies
being undertaken, mainly on a single subject basis. In hemianopic alexia,
the most 'peripheral' of the acquired alexias, where text reading speed is
determined largely by damage to the visual field, therapies have been
directed at improving reading eye movements. In 'pure' alexia, techniques
are usually aimed at improving whole-word recognition. In central alexic
syndromes, where other language functions are also involved, the emphasis
has been on strengthening connections between lexical and semantic
representations, strengthening phonological representations, or both, and
their association with lexical/semantic knowledge. SUMMARY: Despite targeted
approaches to the rehabilitation of patients with alexia caused by stroke,
there is still a preponderance of largely descriptive, single-case studies
in the literature. In some syndromes, small trials have been attempted and
the hope is that, in the future, more systematic investigations will be
carried out so rehabilitation efforts can be built on a strong theoretical
and empirical foundation. Well designed, single-case studies continue to
play an important role in informing therapy, as these disorders are, by
nature, heterogeneous
Wellcome Trust Centre for Neuroimaging, Institute of Neurology, University
College London, UK. a.leff@fil.ion.ucl.ac.uk
McKeeff, T. J. & Behrmann, M. (2004). Pure alexia and covert reading:
Evidence from Stroop tasks. Cognitive Neuropsychology, 21, 443-458.
Notes: T.J. McKeeff, Department of Psychology, Princeton University,
Princeton, NJ 08544
Patients with pure alexia (also referred to as letter-by-letter readers)
show a marked word-length effect when naming visually presented words,
evidenced by a monotonic increase in response time (or decrease in accuracy)
as a function of the number of letters in the string. Interestingly, despite
the difficulty in overtly reporting the identity of some words, many
patients exhibit fast and above-chance access to lexical and/or semantic
information for the same words. To explore the extent of this covert reading,
we examined the degree of interference afforded by the inconsistent (word
identity and colour label do not match) versus neutral condition in a Stroop
task in a pure alexic patient, EL. EL shows evidence of covert reading on a
semantic categorisation task and a lexical decision task. She also
demonstrates covert reading by exhibiting Stroop interference of the same
magnitude as a matched control subject, when naming the colour of the ink in
which a word is printed. When the word shares some but not all letters with
the colour name (BLOW instead of BLUE), neither subject shows interference.
In contrast with the control subject, EL does not show Stroop interference
when various orthographic changes (degraded visual input, cursive font) or
phonological or semantic changes are made to the word. These findings
indicate that although some implicit processing of words may be possible,
this processing is rather rudimentary. Not surprising, this implicit
activation may be insufficient to support overt word identification. We
explain these findings in the context of a single, integrated account of
pure alexia.
Behrmann, M., Shomstein, S. S., Black, S. E., & Barton, J. J. (2001). The
eye movements of pure alexic patients during reading and nonreading tasks.
Neuropsychologia, 39, 983-1002.
Notes: Department of Psychology, Carnegie Mellon University, Pittsburgh, PA
15213-3890, USA. behrmann+@cmu.edu
We compared the eye-movements of two patients who read letter-by-letter (LBL)
following a left occipital lobe lesion with those of normal control subjects
and of hemianopic patients in two tasks: a nonreading visual search task and
a text reading task. Whereas the LBL readers exhibited similar eye-movement
patterns to those of the other two groups on the nonreading task, their eye
movements differed significantly during reading, as reflected in the
disproportionate increase in the number and duration of fixations per word
and in the regressive saccades per word. Importantly, relative to the two
control groups, letter-by-letter readers also made more fixations per word
as word length increased, especially as word frequency and word imageability
decreased. Two critical results emerged from these experiments: First, the
alteration in the oculomotor behavior of the LBL readers during reading is
similar to that seen in normal readers under difficult reading conditions,
as well as in beginning readers and in those with developmental dyslexia,
and appears to reflect difficulties in processing the visual stimulus.
Second, the interaction of length with frequency and with imageability in
determining the eye movement pattern is consistent with an interactive
activation model of normal word recognition in which weakened activation of
orthographic input can nevertheless engage high-level lexical factors
20010920
Montant, M. & Behrmann, M. (2001). Phonological activation in pure alexia.
Cognitive Neuropsychology, 18, 697-727.
Notes: Pure alexia is a reading impairment in which patients appear to read
letter-by-letter. This disorder is typically accounted for in terms of a
peripheral deficit that occurs early on in the reading system, prior to the
activation of orthographic word representations. The peripheral
interpretation of pure alexia has recently been challenged by the
phonological deficit hypothesis, which claims that a postlexical
disconnection between orthographic and phonological information contributes
to or is responsible for the disorder. Because this hypothesis was mainly
supported by data from a single patient (IH), who also has surface dyslexia,
the present study re-examined this hypothesis with another pure alexic
patient (EL). In contrast to patient IH, EL did not show any evidence of a
phonological deficit. Her pattern of performance in naming was not
qualitatively different from that of normal readers; she appeared to be
reading via a mode of processing resulting in strong serial and lexical
effects, a pattern often observed in normal individuals reading unfamiliar
stimuli. The present results do not obviously support the phonological
hypothesis and are more consistent with peripheral interpretations of pure
alexia. The peripheral and the phonological accounts of pure alexia are
discussed in light of two current models of visual word recognition
Montant, M. & Behrmann, M. (2000). Pure alexia. Neurocase, 6,
265-294.
Behrmann, M., Nelson, J., & Sekuler, E. B. (1998). Visual complexity in
letter-by-letter reading: "pure" alexia is not pure. Neuropsychologia,
36, 1115-1132.
Notes: Department of Psychology, Carnegie Mellon University, Pittsburgh, PA
15213-3890, USA. behrmann+@cmu.edu ; ABSTRACT: Standard accounts of pure
alexia have favoured the view that this acquired disorder of reading arises
from damage to a left posterior occipital cortex mechanism dedicated to the
processing of alphanumeric symbols. We challenge these accounts in two
experiments and demonstrate that patients with this reading deficit are also
impaired at object identification. In the first experiment, we show that a
single subject, EL, who shows all the hallmark features of pure alexia, is
impaired at picture identification across a large set of stimuli. As the
visual complexity of pictures increases, so EL's reaction time to identify
the stimuli increases disproportionately relative to the control subjects.
In the second experiment, we confirm these findings with a larger group of
five pure alexic patients using a selected subset of high- and low-visual
complexity pictures. These findings suggest that the deficit giving rise to
pure alexia is not restricted to orthographic symbols per se but, rather, is
a consequence of damage to a more general-purpose visual processing
mechanism 199904
Behrmann, M., Plaut, D. C., & Nelson, J. (1998). A literature review and new
data supporting an interactive account of letter-by-letter reading.
Cognitive Neuropsychology, 15, 7-51.
Notes: We present a theoretical account of letter-by-letter (LBL) reading
that reconciles discrepant findings associated with this form of acquired
dyslexia. We claim that LBL reading is caused by a deficit that affects the
normal activation of the orthographic representation of the stimulus. In
spite of this lower-level deficit, the degraded orthographic information may
be processed further, and lexical, semantic, and higher-order orthographic
information may still influence the reading patterns of these patients. In
support of our position, we present a review of 57 published cases of LBL
reading is presented in which we demonstrate that a peripheral deficit was
evident in almost all of the patients and that, simultaneously, strong
effects of lexical/semantic variables were observed on reading performance.
We then go on to report findings from an empirical analysis of seven LBL
readers in whom we document the joint effects of lexical variables (word
frequency and imageability) and word length on naming latency. We argue that
the reading performance of these patients reflects the residual functioning
of the same interactive system that supported normal reading premorbidly.
Watt,
S., Jokel, R., & Behrmann, M. (1997). Surface dyslexia in nonfluent
progressive aphasia. Brain and Language, 56, 211-233.
Notes: Rotman Research Institute, Baycrest Centre for Geriatric Care,
Toronto, Canada. swatt@io.org This article presents the case of a
59-year-old male, JH, with a 6-year history of primary progressive aphasia (PPA),
a disorder characterized by isolated language deterioration with relative
preservation of other cognitive abilities. JH also shows typical features of
surface dyslexia, a reading disorder exemplified by the selective
preservation of phonological reading. One recent theory is that surface
dyslexia in individuals with PPA results from a loss of semantic knowledge.
In this paper we consider an additional possibility and present data
supporting the notion that surface dyslexia may also arise from the
malfunction in the links between semantic representations and phonology. JH
has remarkably preserved lexical semantic knowledge when assessed on tasks
that do not require verbal output. Further, item-by-item comparisons of his
oral reading and comprehension ability show no significant correspondence
between his reading and semantic knowledge. These findings lead us to
conclude that, in JH's case, the surface dyslexia is attributable not to a
semantic deficit per se but rather to the inability to access phonological
information from semantics. JH's language profile is considered in relation
to potential sources of surface dyslexia and other cases of progressive
aphasia 9706
Behrmann, M. & McLeod, J. (1995). Rehabilitation for pure alexia: Efficacy
of therapy and implications for models of normal word recognition.
Neuropsychological Rehabilitation, 5, 149-180.
Behrmann, M. & Shallice, T. (1995). Pure alexia: A nonspatial visual
disorder affecting letter activation. Cognitive Neuropsychology, 12,
409-454.
Notes: Several different interpretations have been offered to explain the
mechanism giving rise to the linear relationship between word length and
reading time shown by patients with pure alexia or letter-by-letter reading.
One interpretation attributes this word length effect to a spatial
impairment in which there is a left- right gradient of processing efficiency.
This fundamental resource limitation requires that the patient focus on each
letter in turn to increase its signal-to-noise ratio and discriminability,
especially for letters towards the end of the string. An alternative view
attributes the word length effect to a letter activation deficit that
disrupts the rapid and efficient processing of single letters. In this paper,
we examine these two hypotheses in relation to DS, a letter-by-letter reader.
DS is able to distribute her attention to multiple locations in parallel and
her performance is unaffected by the absolute or relative spatial location
of the letters in a string. She is, however, impaired at reporting the
identity of a letter independent of its spatial location and requires an
abnormally long time to process each letter. Furthermore, investigations of
DS's reading, using Howard's (1991) analyses of reaction time distributions,
suggest that she processes each letter in a sequentially order. Based on the
results of these studies, we propose that prototypic pure alexia is a
nonspatial visual disorder that affects the activation of individual letters
Behrmann, M. (1994). Neglect dyslexia: Attention and word recognition. In
M.J.Farah & G. Ratcliff (Eds.), The neuropsychology of high-level vision.
Collected tutorial essays (pp. 173-214). Hillsdale,NJ: Erlbaum.
Black,
S. E. & Behrmann, M. (1994). Localization in alexia. In A.Kertesz (Ed.),
Localization and neuroimaging in neuropsychology (1 ed., pp. 331-376).
San Diego: Academic Press.
Notes: (The authors combine a review of the classical lesion evidence, the
anatomy of the visual system, and the rapidly growing literature on various
models of reading with the results of recent 15O PET imaging studies and the
information processing approach in cognitive psychology. Included are their
own studies of neglect dyslexia)
Klein,
D., Behrmann, M., & Doctor, E. (1994). The evolution of deep dyslexia:
Evidence for the spontaneous recovery of the semantic reading route.
Cognitive Neuropsychology, 11, 579-611.
Notes: Most theoretical accounts of deep dyslexia postulate at least two
independent deficits which give rise to the observed pattern of reading
impairment. One deficit is an inability to derive phonology from ortography
sublexically and the second is an impairment in semantically mediated
reading. These deficits generate a host of symptoms including an impairment
in reading nonwords, a part-of-speech and imageability effect in word
reading, and, importantly, the occurrence of semantic paraphasias. It is
possible, then, that during recovery of deep dyslexia, either one or both of
these underlying deficits resolve. We describe a case, RL, with deep
dyslexia who showed significant change in his reading performance in the
absence of any therapeutic intervention. At 18 months post-onset, unlike at
6 months post-onset, RL no longer produced any purely semantic errors nor
did he show effects of imageability or part-of-speech on his oral reading.
Despite this change, RL's ability to read nonwords did not improve
significantly over this time period. These findings suggest that selective
and spontaneous recovery of the semantic reading route can occur independent
of significant change in the sublexical reading route
Behrmann, M. & Bub, D. (1992). Surface dyslexia and dysgraphia: Dual routes,
single lexicon. Cognitive Neuropsychology, 9, 209-251.
Notes: The dual route interpretation of surface dyslexia as a deficit in
word-specific activation has been challenged recently by computational
models that incorporate a unitary print-to-sound mechanism. The most current
of these makes no allowance for word-specific nodes, but obtains the
pronounciation of regular and exception words by weighted connections
between graphemic and phonemic units. Damaging the model in a variety of
ways produces a pattern that appears consistent with the performance of many
surface dyslexic patients. Exception words are mispronounced more often than
regular words, though accuracy deteriorates on both categories. In addition,
frequency has no clear-cut effect on the probability of reading an exception
word correctly. We describe the existence of a variant of the syndrome that
is not fully captured by the above simulations. MP, a surface dyslexic,
demonstrates a dissociation between lexical and nonlexical pronounciation of
written words. We also show that performance on irregular words varies as a
function of their frequency. We provide evidence that the locus of the
subject's deficit arises at the level of the representations in a single
orthographic lexicon that subserves both reading and writing
Behrmann, M., Moscovitch, M., & Mozer, M. (1991). Directing attention to
words and nonwords in normal subjects and in a computational model:
Implications for neglect dyslexia. Cognitive Neuropsychology, 8,
213-248.
Notes: In a previous paper we suggested that patients with neglect dyslexia
process information appearing on the unattended side. This information, if
encoded sufficiently, may be used to trigger top-down knowledge, leading to
the interaction of spatial attention and lexicality. The current studies
examine this question in normal people. Subjects' attention was biased to
the end of a letter string by a cue (underline bar), and lexical decisions
were made to the underlined section of the letter string (for example, east
and garm). These studies showed that reaction times were slower when
distracting information appeared on the left than when no distractors were
present (for example, arm). Furthermore, when the distractors played a
lexical role and formed a word with the underlined string (for example
farm), lexical decisions were even slower. These results showed that
distractors are processed at least to the level of lexical access and
influence reading performance of the attended underlined string. We have
also considered these findings in the light of an existing connectionist
network of spatial attention and word recognition and have accounted for the
data in a series of simulations. The convergence of findings from the
neuropsychological, cognitive, and computational work supports the
interaction between attention and higher-order lexical knowledge.
Behrmann, M., Moscovitch, M., Black, S. E., & Mozer, M. (1990). Perceptual
and conceptual mechanisms in neglect dyslexia. Two contrasting case studies.
Brain, 113, 1163-1183.
Notes: The contribution of peripheral, data-driven effects is contrasted
with conceptual, 'top-down' effects to the reading performance of 2 subjects
with neglect dyslexia following a single right hemisphere lesion. Several
tasks were administered, manipulating the physical, lexical or morphemic
properties of the stimuli in an attempt to establish whether the attentional
deficit disrupts reading at an early or late stage of processing. Both
subjects were impaired at detecting elementary stimulus features on the left
side of the display but were even more impaired at identifying conjoined
features. One subject's performance was influenced by structural
manipulations which altered the low-level representation of the stimulus.
The other was less affected by structural changes of the stimuli but was
influenced by the lexical and morphemic status of the words. This apparent
double dissociation is interpreted as arising from a graded attentional
deficit at a single locus, early in the reading process where low-level
information is detected. When the deficit is not severe sufficient
information may be picked up and may interact with higher order lexical
knowledge to offset partially the peripheral malfunction. For a severe
attentional deficit, top-down knowledge is not engaged as insufficient
information is processed on the left-hand side. This hybrid view of
attention provides insight into the mechanisms underlying neglect dyslexia
and bears on the role of attention in normal visual processing
Behrmann, M., Black, S. E., & Bub, D. (1990). The evolution of pure alexia:
a longitudinal study of recovery. Brain and Language, 39, 405-427.
Notes: Department of Psychology, University of Toronto, Ontario, Canada This
case report documents the partial recovery, over a 12-month period, of pure
alexia in an adult female following a left occipital infarction. Measures of
speed and accuracy were obtained on an oral reading and a lexical decision
task immediately postonset and then on 10 subsequent occasions. Explicit
letter-by-letter reading was observed only during the first week poststroke
but a significant effect of word length was seen in all testing sessions.
Reading accuracy was relatively good at all stages and reading latency
showed a remarkable decrease over time but did not reach normal reading
rates. The inability to use higher-order orthographic knowledge, as manifest
in the absence of a word superiority effect, was still noted at one year
postonset. We therefore concluded that the change in behavior was
attributable to increased proficiency in the use of the adaptive
letter-by-letter procedure rather than to the resolution of the underlying
deficit. It is suggested that longitudinal neurobehavioral studies add to
our understanding of the alexic deficit and provide insight into the
recovery process
Mozer,
M. C. & Behrmann, M. (1990). On the interaction of selective attention and
lexical knowledge: A connectionist account of neglect dyslexia. Journal
of Cognitive Neuroscience, 2, 96-123.
Behrmann, M. (1987). The rites of righting writing: Homophone remediation in
acquired dysgraphia. Cognitive Neuropsychology, 4, 365-384.
Notes: A homophone retraining program was implemented with a surface
dysgraphic patient. Extensive pretherapy testing suggested that lexical
processing was impaired in writing but not in reading, resulting in
difficulties in writing homophones and irregular words. The treatment
procedure involved the pairing of the written homophone with its pictorial
representation in order to link the orthography with the corresponding
meaning and to enhance direct lexical access. A series of exercises and
practice techniques were introduced to strenghten this route. Results reveal
significant improvement in writing treated homophones and untreated
irregular words but minimal generalization to untreated homophones.
Theoretical explanations for the changes are offered and the efficacy of the
treatment program is demonstrated. |
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