A Characterisation of the Word Superiority Effect in a Case of Letter-by-letter Surface Alexia

An important characteristic of the word superiority effect (WSE) observed in normal subjects is that it extends to words displayed in mixed-case letters, e.g. fAdE is better identified than gAdE (McClelland, 1976). Because upper- and lower-case letters are treated as functionally equivalent within the orthographic system (e.g. “A”/“a” map onto abstract letter identities; Coltheart, 1981), it is often argued that orthographic codes mediate the WSE. In the present paper, we report an intact WSE in a letter-by-letter surface alexic (IH) when words and “word-like” pseudowords were displayed quickly and then masked. Consistent with the claim that orthographic codes mediated these effects, the WSE extended to words typed in mixed-case letters, and IH failed to show a WSE for the same class of words for which he has impaired orthographic knowledge; namely, low frequency words. Based on these results, we argue that IH gains better access to orthographic knowledge than current theories of letter-by-letter reading ...

[1]  John Morton,et al.  Facilitation in Word Recognition: Experiments Causing Change in the Logogen Model , 1979 .

[2]  D. Bub,et al.  On the methodology of single-case studies in cognitive neuropsychology , 1988 .

[3]  J L Bradshaw,et al.  Hemispheric asymmetry: verbal and spatial encoding of visual stimuli. , 1972, Journal of experimental psychology.

[4]  G. Humphreys,et al.  Letter-by-letter reading? Functional deficits and compensatory strategies , 1992 .

[5]  W. Estes.  The Locus of Inferential and Perceptual Processes in Letter Identification. , 1975 .

[6]  M. Behrmann,et al.  Surface dyslexia and dysgraphia: dual routes, single lexicon , 1992 .

[7]  S. Kosslyn,et al.  Form-specific visual priming in the right cerebral hemisphere. , 1992, Journal of experimental psychology. Learning, memory, and cognition.

[8]  G. Humphreys,et al.  The Use of Abstract Graphemic Information in Lexical Access , 1981 .

[9]  Mark S. Seidenberg,et al.  Chapter 5 Beyond Orthographic Depth in Reading: Equitable Division of Labor , 1992 .

[10]  Patricia A. Reuter-Lorenz,et al.  Modes of Lexical Access in the Callosotomized Brain , 1992, Journal of Cognitive Neuroscience.

[11]  Daniel N. Bub,et al.  Word recognition and orthographic context effects in a letter-by-letter reader , 1989, Brain and Language.

[12]  D. Bub,et al.  Single-character processing in a case of pure alexia , 1993, Neuropsychologia.

[13]  Karalyn Patterson,et al.  Letter-by-letter Reading: Psychological Descriptions of a Neurologial Syndrome , 1982 .

[14]  J. Grainger,et al.  Phonology and Orthography in Visual Word Recognition: Effects of Masked Homophone Primes , 1994 .

[15]  D. Bub,et al.  Visual Word Activation in Pure Alexia , 1995, Brain and Language.

[16]  G. Waters,et al.  Working memory and written sentence comprehension , 1987 .

[17]  Max Coltheart,et al.  Access to the internal lexicon , 1977 .

[18]  B. Bergum,et al.  Attention and Performance VI , 1978 .

[19]  J. Kay,et al.  Simultaneous Form Perception and Serial Letter Recognition in a Case of Letter-by-letter Reading , 1991 .

[20]  Faraneh Vargha-Khadem,et al.  READING WITH ONE HEMISPHERE , 1989 .

[21]  J. L. Mcclelland.  Preliminary letter identification in the perception of words and nonwords. , 1976, Journal of experimental psychology. Human perception and performance.

[22]  James L. McClelland,et al.  The role of familiar units in perception of words and nonwords , 1977 .

[23]  H. Kucera,et al.  Computational analysis of present-day American English , 1967 .

[24]  James C Johnston,et al.  A test of the Sophisticated Guessing Theory of word perception , 1978, Cognitive Psychology.

[25]  James F. Juola,et al.  Letter identification in word, nonword, and single-letter displays , 1974 .

[26]  Tim Shallice,et al.  Lexical processing in the absence of explicit word identification: Evidence from a letter-by-letter reader , 1986 .

[27]  Rosaleen A. McCarthy,et al.  Reading without Semantics , 1983 .

[28]  M Coltheart,et al.  Basic processes in reading: computation of abstract letter identities. , 1984, Canadian journal of psychology.

[29]  S. Andrews.  Frequency and neighborhood effects on lexical access: Activation or search? , 1989 .

[30]  James L. McClelland,et al.  An interactive activation model of context effects in letter perception: I. An account of basic findings. , 1981 .

[31]  M. Farah.  Neuropsychological inference with an interactive brain: A critique of the "locality" assumption. , 1994 .

[32]  E. Warrington,et al.  A disorder of simultaneous form perception. , 1962, Brain : a journal of neurology.

[33]  Marilyn Jager Adams,et al.  Models of word recognition , 1979, Cognitive Psychology.

[34]  M. Behrmann,et al.  The evolution of pure alexia: A longitudinal study of recovery , 1990, Brain and Language.

[35]  H. Branch Coslett,et al.  Reading in pure alexiaThe effect of strategy , 1993 .

[36]  M. S. Mayzner,et al.  Tables of single-letter and digram frequency counts for various word-length and letter-position combinations. , 1965 .

[37]  Patricia A. Reuter-Lorenz,et al.  A prelexical basis for letter-by-letter reading: A case study , 1990 .

[38]  W. Nelson Francis,et al.  FREQUENCY ANALYSIS OF ENGLISH USAGE: LEXICON AND GRAMMAR , 1983 .

[39]  D N Levine,et al.  A study of the visual defect in verbal alexia-simultanagnosia. , 1978, Brain : a journal of neurology.

[40]  D. Bub,et al.  Priming and response selection processes in letter classification and identification tasks. , 1995 .

[41]  J. Hodges,et al.  Deterioration of word meaning: Implications for reading , 1992, Neuropsychologia.

[42]  Michael C. Doyle,et al.  Effects of frequency on visual word recognition tasks: where are they? , 1989, Journal of experimental psychology. General.

[43]  M. Coltheart.  Disorders of reading and their implications for models of normal reading. , 1981 .

[44]  T Shallice,et al.  Word-form dyslexia. , 1980, Brain : a journal of neurology.

[45]  Ram Frost,et al.  Orthography, phonology, morphology, and meaning , 1992 .

[46]  Martha J. Farah,et al.  Pure Alexia as a Visual Impairment: A Reconsideration , 1991 .

[47]  Jeffrey A. Hadley,et al.  Letter-by-letter surface alexia , 1992 .

[48]  L. Manelis.  The effect of meaningfulness in tachistoscopic word perception , 1974 .

[49]  H. Coslett,et al.  Evidence for preserved reading in 'pure alexia'. , 1989, Brain : a journal of neurology.