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Fischer-Baum, S., McCloskey, M., & Rapp, B. (2010). Representation of letter
position in spelling: evidence from acquired dysgraphia. Cognition, 115,
466-490.
Notes: The graphemic representations that underlie spelling performance must
encode not only the identities of the letters in a word, but also the
positions of the letters. This study investigates how letter position
information is represented. We present evidence from two dysgraphic
individuals, CM and LSS, who perseverate letters when spelling: that is,
letters from previous spelling responses intrude into subsequent responses.
The perseverated letters appear more often than expected by chance in the
same position in the previous and subsequent responses. We used these errors
to address the question of how letter position is represented in spelling.
In a series of analyses we determined how often the perseveration errors
produced maintain position as defined by a number of alternative theories of
letter position encoding proposed in the literature. The analyses provide
strong evidence that the grapheme representations used in spelling encode
letter position such that position is represented in a graded manner based
on distance from both-edges of the word
Department of Cognitive Science, Johns Hopkins University, Baltimore, MD
21218, USA. fischerbaum@cogsci.jhu.edu
McCloskey, M., Macaruso, P., & Rapp, B. (2006). Grapheme-to-lexeme feedback
in the spelling system: Evidence from a dysgraphic patient. Cognitive
Neuropsychology, 23, 278-307.
Notes: M. McCloskey, Department of Cognitive Sciences, Johns Hopkins
University, Krieger Hall, Baltimore, MD 21218
This article presents an argument for grapheme-to-lexeme feedback in the
cognitive spelling system, based on the impaired spelling performance of
dysgraphic patient CM. The argument relates two features of CM's spelling.
First, letters from prior spelling responses intrude into subsequent
responses at rates far greater than expected by chance. This letter
persistence effect arises at a level of abstract grapheme representations,
and apparently results from abnormal persistence of activation. Second, CM
makes many formal lexical errors (e.g., carpet < right-arrow > compute).
Analyses revealed that a large proportion of these errors are "true" lexical
errors originating in lexical selection, rather than "chance" lexical errors
that happen by chance to take the form of words. Additional analyses
demonstrated that CM's true lexical errors exhibit the letter persistence
effect. We argue that this finding can be understood only within a
functional architecture in which activation from the grapheme level feeds
back to the lexeme level, thereby influencing lexical selection.
McCloskey, M. (2003). Beyond task dissociation logic: a richer conception of
cognitive neuropsychology. Cortex, 39, 196-202.
Notes: Department of Cognitive Science, Johns Hopkins University, Baltimore,
MD 21218, USA. michael.mccloskey@jhu.edu
McCloskey, M. (2001). The future of cognitive neuropsychology. In B.Rapp
(Ed.), The handbook of cognitive neuropsychology (pp. 593-610).
Philadelphia,PA: Psychology Press.
McCloskey, M., Badecker, W., Goodman-Schulman, R. A., & Aliminosa, D.
(1994). The structure of graphemic representations in spelling: Evidence
from a case of acquired dysgraphia. Cognitive Neuropsychology, 11,
341-392.
Notes: A single-case study of an acquired dysgraphic patient is presented.
On the basis of the patient's pattern of spelling errors, and especially his
errors on words with the geminate letters (e.g. "cross" spelled croos), it
is argued that stored spelling representations are not simple linear
sequences of letter tokens (e.g. C-R-O-S-S). Rather, it is proposed that the
graphemic representations processed by the cognitive spelling mechanisms are
multidimensional structures that encode separately letter position, letter
identity, letter doubling, and consonant/wovel status
Caramazza, A. & McCloskey, M. (1988). The case for single-patient studies.
Special Issue: Methodological problems in cognitive neuropsychology.
Cognitive Neuropsychology, 5, 517-527.
Notes: It is argued that only single-patient studies allow valid inferences
about normal cognitive processes from the analysis of acquired cognitive
disorders. The arguments in favor of this position support the further claim
that clinical classifications such as agrammatism and deep dyslexia are
theoretically useless.
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