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Alexia With and Without Agraphia: An Assessment of Two Classical Syndromes

Published online by Cambridge University Press:  02 December 2014

Claire A. Sheldon ,
George L. Malcolm  and
Jason J.S. Barton
Claire A. Sheldon
Affiliation:
Department of Medicine (Neurology), Ophthalmology and Visual Science, and Psychology, University of British Columbia, Vancouver, BC, Canada
George L. Malcolm
Affiliation:
Department of Medicine (Neurology), Ophthalmology and Visual Science, and Psychology, University of British Columbia, Vancouver, BC, Canada
Jason J.S. Barton*
Affiliation:
Department of Medicine (Neurology), Ophthalmology and Visual Science, and Psychology, University of British Columbia, Vancouver, BC, Canada
*
Neuro-ophthalmology Section D, VGH Eye Care Center, 2550 Willow Street, Vancouver, BC, Canada, V5Z 3N9.
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Abstract

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Background:

Current cognitive models propose that multiple processes are involved in reading and writing.

Objective:

Our goal was to use linguistic analyses to clarify the cognitive dysfunction behind two classic alexic syndromes.

Methods:

We report four experiments on two patients, one with alexia without agraphia following occipitotemporal lesions, and one with alexia with agraphia from a left angular gyral lesion.

Results:

The patient with occipital lesions had trouble discriminating real letters from foils and his reading varied with word-length but not with linguistic variables such as part of speech, word frequency or imageability. He read pseudo-words and words with regular spelling better, indicating preserved use of grapheme-to-phoneme pronunciation rules. His writing showed errors that reflected reliance on ‘phoneme-to-grapheme’ spelling rules. In contrast, the patient with a left angular gyral lesion showed better recognition of letters, words and their meanings. His reading was better for words with high imageability but displayed semantic errors and an inability to use ‘grapheme-to-phoneme’ rules, features consistent with deep dyslexia. His agraphia showed impaired access to both an internal lexicon and ‘phoneme-to-grapheme’ rules.

Conclusion:

Some cases of pure alexia may be a perceptual word-form agnosia, with loss of internal representations of letters and words, while the angular gyral syndrome of alexia with agraphia is a linguistic deep dyslexia. The presence or absence of agraphia does not always distinguish between the two; rather, writing can mirror the reading deficits, being more obvious and profound in the case of an angular gyral syndrome.

Résumé:

RÉSUMÉ:Contexte:

Selon les modèles cognitifs actuels, plusieurs processus sont impliqués dans la lecture et l'écriture.

Objectif:

Notre but était d'utiliser l'analyse linguistique pour clarifier la dysfonction cognitive sous-jacente à deux syndromes alexiques classiques.

Méthodes:

Nous rapportons quatre expériences effectuées chez deux patients, dont l'un présentait une alexie sans agraphie suite à des lésions occipitotemporales et l'autre une alexie avec agraphie suite à une lésion gyrale angulaire gauche.

Résultats:

Le patient porteur de lésions occipitales avait de la difficulté à distinguer de vraies lettres de simulacres de lettres et la lecture variait selon la longueur des mots, indépendamment de variables linguistiques comme la partie du discours, la fréquence des mots ou l'imageabilité. Il lisait des pseudo mots et il lisait mieux les mots dont l'épellation était régulière, ce qui indique que l'utilisation des règles de prononciation de graphème à phonème était préservée. À l'écriture on notait des erreurs qui témoignaient qu'il se fiait aux règles d'épellation de phonème à graphème. Par contre, le patient porteur l'une lésion gyrale angulaire gauche avait une meilleure reconnaissance des lettres et des mots ainsi que de leur signification. Sa lecture des mots dont l'imageabilité est élevée était meilleure, mais il faisait des erreurs de sémantique et était incapable d'utiliser les règles de graphème à phonème, témoignant d'une dylexie profonde. Son agraphie témoignait d'une altération de l'accès à un lexique interne et aux règles de phonème à graphème.

Conclusion:

Certains cas d'alexie pure peuvent être une agnosie de perception de la forme des mots avec perte de la représentation interne des lettres et des mots alors que le syndrome gyral angulaire d'alexie avec agraphie est une dyslexie profonde linguistique. La présence ou l'absence d'agraphie ne permet pas toujours de faire la distinction entre les deux. L'écriture peut refléter les déficits de lecture qui sont plus évidents et plus sévères chez les patients atteints du syndrome gyral angulaire.

Type
Research Article
Information
Canadian Journal of Neurological Sciences , Volume 35 , Issue 5 , November 2008 , pp. 616 - 624
Copyright
Copyright © The Canadian Journal of Neurological 2008

References

1. Black, SE, Behrmann, M. Localization in Alexia. In: Kertesz, A, editor. Localization and neuroimaging in neuropsychology. San Diego: Academic Press; 1994. p. 331–76.Google Scholar
2. Dalmas, JF, Dansilio, S. Visuographemic alexia: a new form of a peripheral acquired dyslexia. Brain Lang. 2000;75(1):1–16.Google Scholar
3. Behrmann, M, Nelson, J, Sekuler, EB. Visual complexity in letter-by-letter reading: “pure” alexia is not pure. Neuropsychologia. 1998;36(11):1115–32.Google Scholar
4. Goethals, M, Santens, P. Posterior cortical atrophy. Two case reports and a review of the literature. Clin Neurol Neurosurg. 2001;103(2):115–19.Google Scholar
5. Coslett, HB. Acquired dyslexia. Semin Neurol. 2000;20(4):419–26.Google Scholar
6. Bub, D. Alexia and related reading disorders. Neurol Clin. 2003;21(2):549–68.CrossRefGoogle ScholarPubMed
7. De Renzi, E, di Pellegrino, G. Prosopagnosia and alexia without object agnosia. Cortex. 1998;34(3):403–15.Google Scholar
8. Buxbaum, LJ, Glosser, G, Coslett, HB. Impaired face and word recognition without object agnosia. Neuropsychologia. 1999;37(1):41–50.Google Scholar
9. Marshall, JC, Newcombe, F. Patterns of paralexia: a psycholinguistic approach. J Psycholinguist Res. 1973;2(3):175–99.Google Scholar
10. Marchand, Y, Friedman, RB. Impaired oral reading in two atypical dyslexics: a comparison with a computational lexical-analogy model. Brain Lang. 2005(3);93:255–66.Google Scholar
11. Coltheart, M. The MRC psycholinquistic database. Q J Exp Psychol. 1981;33A:497–505.Google Scholar
12. Newton, PK, Barry, C. Concreteness effects in word production by not word comprehension in deep dyslexia. Cog Neuropsychol. 1997;14:481–509.Google Scholar
13. McLeod, P, Shallice, T, Plaut, DC. Attractor dynamics in word recognition: converging evidence from errors by normal subjects, dyslexic patients and a connectionist model. Cognition. 2000;74(1):91–114.Google Scholar
14. Colangelo, A, Buchanan, L. Semantic ambiguity and the failure of inhibition hypothesis as an explanation for reading errors in deep dyslexia. Brain Cogn. 2005;57(1):39–42.Google Scholar
15. Beeson, PM. Remediation of written language. Top Stroke Rehabil. 2004;11(1):37–48.CrossRefGoogle ScholarPubMed
16. Ogden, JA. Phonological dyslexia and phonological dysgraphia following left and right hemispherectomy. Neuropsychologia. 1996;34(9):905–18.Google Scholar
17. Cipolotti, L, Warrington, EK. Does recognizing orally spelled words depend on reading? An investigation into a case of better written than oral spelling. Neuropsychologia. 1996;34(5):427–40.Google Scholar
18. Rapcsak, SZ, Beeson, PM. The role of left posterior inferior temporal cortex in spelling. Neurology. 2004;62(12):2221–9.Google Scholar
19. Kim, HJ, Chu, K, Lee, KM, Kim, DW, Park, SH. Phonological agraphia after superior temporal gyrus infarction. Arch Neurol. 2002;59(8):1314–16.Google Scholar
20. Mao-Draayer, Y, Panitch, H. Alexia without agraphia in multiple sclerosis: case report with magnetic resonance imaging localization. Mult Scler. 2004;10(6):705–7.Google Scholar
21. Bub, DN, Arguin, M, Lecours, AR. Jules Dejerine and his interpretation of pure alexia. Brain Lang. 1993;45(4):531–59.Google Scholar
22. Geschwind, N. Disconnexion syndromes in animals and man. I. Brain. 1965;88(2):237–94.Google Scholar
23. Damasio, AR, Damasio, H. Hemianopia, hemiachromatopsia and the mechanisms of alexia. Cortex. 1986;22(1):161–9.CrossRefGoogle ScholarPubMed
24. Stommel, EW, Friedman, RJ, Reeves, AG. Alexia without agraphia associated with spleniogeniculate infarction. Neurology. 1991;41(4):587–8.Google Scholar
25. Tamhankar, MA, Coslett, HB, Fisher, MJ, Sutton, LN, Liu, GT. Alexia without agraphia following biopsy of a left thalamic tumor. Pediatr Neurol. 2004;30(2):140–2.Google Scholar
26. Warrington, EK, Shallice, T. Word-form dyslexia. Brain. 1980;103(1):99–112.Google Scholar
27. Benito-Leon, J, Sanchez-Suarez, C, Diaz-Guzman, J, Martinez-Salio, A. Pure alexia could not be a disconnection syndrome. Neurology. 1997;49:305–6.Google Scholar
28. Rentschler, I, Treutwein, B, Landis, T. Dissociation of local and global processing in visual agnosia. Vision Res. 1994;34(7): 963–71.Google Scholar
29. Miozzo, M, Caramazza, A. Varieties of pure alexia: the case of failure to access graphemic representations. Cogn Neuropsychol. 1998;15(1/2):203–38.Google Scholar
30. Sakurai, Y. Varieties of alexia from fusiform, posterior inferior temporal and posterior occipital gyrus lesions. Behav Neurol. 2004;15:35–50.Google Scholar
31. Cohen, L, Martinaud, O, Lemer, C, Lehericy, S, Samson, Y, Obadia, M, et al. Visual word recognition in the left and right hemispheres: anatomical and functional correlates of peripheral alexias. Cereb Cortex. 2003;13(12):1313–33.Google Scholar
32. Colangelo, A, Stephenson, K, Westbury, C, Buchanan, L. Word associations in deep dyslexia. Brain Cogn. 2003;53(2):166–70.Google Scholar
33. McEwen, S, Westbury, C, Buchanan, L, Libben, G. Semantic information is used by a deep dyslexic to parse compounds. Brain Cogn. 2001;46(1-2):201–5.CrossRefGoogle ScholarPubMed
34. Nolan, KA, Volpe, BT, Burton, LA. The continuum of deep/surface dyslexia. J Psycholinguist Res. 1997;26(4):413–24.Google Scholar
35. Glosser, G, Friedman, RB. The continuum of deep/phonological alexia. Cortex. 1990;26(3):343–59.Google Scholar
36. Jobard, G, Crivello, F, Tzourio-Mazoyer, N. Evaluation of the dual route theory of reading: a metanalysis of 35 neuroimaging studies. Neuroimage. 2003;20(2):693–712.Google Scholar
37. Coslett, HB, Monsul, N. Reading with the right hemisphere: evidence from transcranial magnetic stimulation. Brain Lang. 1994;46(2):198–211.Google Scholar
38. Coltheart, M. Deep dyslexia is right-hemisphere reading. Brain Lang. 2000;71(2):299–309.Google Scholar