Rapp, B. & Lipka, K. (2011). The literate brain: the relationship between
spelling and reading. Journal of Cognitive Neuroscience, 23,
1180-1197.
Notes: We report the results of an fMRI investigation of the neural bases of
written language comprehension (reading) and production (spelling). Both
tasks were examined in the same individuals, allowing greater precision in
establishing the relationship between the neural underpinnings of these two
cognitive functions. Also examined was the relationship between written
language substrates and those involved in face and object (house)
processing. The results reveal that reading and spelling share specific left
hemisphere substrates in the mid-fusiform gyrus and in the inferior frontal
gyrus/junction. Furthermore, the results indicate that the left mid-fusiform
substrates are specifically involved in lexical orthographic processing. We
also find that written language and face processing exhibit largely
complementary activation patterns in both the fusiform and the inferior
frontal/junction areas, with left and right lateralization, respectively. In
sum, these results provide perhaps the strongest evidence to date of
components that are shared by written language comprehension (reading) and
production (spelling), and they further our understanding of the role of
literacy within the larger repertoire of cognitive operations and their
neural substrates
Department of Cognitive Science, Johns Hopkins University, Baltimore, MD
21218, USA. e-mail: rapp@cogsci.jhu.edu
Tsapkini, K., Vindiola, M., & Rapp, B. (2011). Patterns of brain
reorganization subsequent to left fusiform damage: fMRI evidence from visual
processing of words and pseudowords, faces and objects. NeuroImage, 55,
1357-1372.
Notes: Little is known about the neural reorganization that takes place
subsequent to lesions that affect orthographic processing (reading and/or
spelling). We report on an fMRI investigation of an individual with a left
mid-fusiform resection that affected both reading and spelling (Tsapkini &
Rapp, 2010). To investigate possible patterns of functional reorganization,
we compared the behavioral and neural activation patterns of this individual
with those of a group of control participants for the tasks of silent
reading of words and pseudowords and the passive viewing of faces and
objects, all tasks that typically recruit the inferior temporal lobes. This
comparison was carried out with methods that included a novel application of
Mahalanobis distance statistics, and revealed: (1) normal behavioral and
neural responses for face and object processing, (2) evidence of neural
reorganization bilaterally in the posterior fusiform that supported normal
performance in pseudoword reading and which contributed to word reading (3)
evidence of abnormal recruitment of the bilateral anterior temporal lobes
indicating compensatory (albeit insufficient) recruitment of mechanisms for
circumventing the word reading deficit
Department of Neurology, Johns Hopkins University School of Medicine,
Baltimore, MD 21205, USA. tsapkini@jhmi.edu
Tsapkini, K. & Rapp, B. (2010). The orthography-specific functions of the
left fusiform gyrus: evidence of modality and category specificity.
Cortex, 46, 185-205.
Notes: We report on an investigation of the cognitive functions of an
individual with a resection of the left fusiform gyrus. This individual and
a group of control participants underwent testing to examine the question of
whether or not there are neural substrates within the left fusiform gyrus
that are dedicated to orthographic processing. We evaluated the modality
specificity (written vs spoken language) and the category specificity
(written language vs other visual categories) of this individual's
impairments. The results clearly reveal deficits affecting lexical processes
in both reading and spelling. Specifically, we find disruption of normal,
rapid access to meaning from print in reading and of accurate retrieval of
the spellings of words from their meaning in writing. These deficits stand
in striking contrast with intact processing of spoken language and
categories of visual stimuli such as line drawings of objects and faces. The
modality and category specificity of the deficits provide clear evidence of
neural substrates within the left-mid-fusiform gyrus that are specialized
and necessary for normal orthographic processing
Department of Cognitive Science, Johns Hopkins University, Baltimore, MD
21218-2685, USA. tsapkini@cogsci.jhu.edu
Jones,
A. C., Folk, J. R., & Rapp, B. (2009).
All letters are not equal: subgraphemic texture in orthographic working
memory. Journal of Experimental Psychology: Learning,Memory,and
Cognition, 35, 1389-1402.
Notes: A central issue in the study of reading and spelling has been to
understand how the consistency or frequency of letter-sound relationships
affects written language processing. We present, for the first time,
evidence that the sound-spelling frequency of subgraphemic elements of words
(letters within digraphs) contributes to the accuracy with which these
letters are produced in spelling. We report findings from 2 studies that
demonstrate that letters within digraphs display differential susceptibility
to error under conditions of disruption to orthographic working memory
(O-WM). In the 1st, O-WM was disrupted as a result of neurological damage;
in the 2nd, O-WM disruption was produced in neurologically intact, skilled
spellers under dual task conditions with a shadowing task carried out during
spelling. In both studies, segments with low versus high levels of
sound-letter convergence, a measure of the frequency of sublexical mappings,
were more vulnerable to disruption even when factors such as letter
position, consonant-vowel context, and phoneme-to-grapheme mapping
probability of the digraphs were controlled. These results contribute to our
understanding of the internal texture of orthographic representations,
providing evidence that individual letters differ in their activation
strength and, as a result, in their susceptibility to error
Rapp,
B., Folk, J. R., & Tainturier, M. J. (2001).
Word reading. In B.Rapp (Ed.), The handbook of cognitive neuropsychology
(pp. 233-262). Philadelphia,PA: Psychology Press.
Badecker, W., Rapp, B., & Caramazza, A. (1996). Lexical morphology and the
two orthographic routes. Cognitive Neuropsychology, 13, 161-175.
Rapp, B. C. & Caramazza, A. (1991). Spatially determined deficits in letter
and word processing. Cognitive Neuropsychology, 8, 275-311.
Notes: We describe the performance of a brain-damaged subject, HR, whose
reading performance can be described as letter-by-letter reading. On a
number of experimental tasks she exhibited deficits in letter and bar
detection. Her performance in these tasks indicated that her impairment in
nonlexical letter detection tasks was spatially determined. We interpretthe
results within a multi-stage model of prelexical visual/perceptual
processing. Within such a model, the impairments can be attributed to
deficits at retino- centric and stimulus-centered levels of representation.
We explain HR's letter-by-letter reading performance in terms of these
deficits. In addition, we attempt to account for the differences in reading
performance among patients with spaitally determined deficits in terms of
the proposed multi-stage model of word recognition.
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