Some Aspects of Language Processing Revealed Through the Analysis of Acquired Aphasia: The Lexical System

Abstract

395 0147-006X/88/0301-0395502.00 www.annualreviews.org/aronline Annual Reviews Annu. Rev. Neurosci. 1988.11:395-421. Downloaded from arjournals.annualreviews.org by HARVARD UNIVERSITY on 10/18/07. For personal use only.ASPECTS OF LANGUAGE PROCESSING 397 entitle" theory of cognitive abilities will not be formulated by directly relating behavior to neural events but through the mediation of cognitive operations. Cognitive neuropsychology rejects as prejudicial the eliminative materialism of some neuroscientists [and philosophers; cf Churchland (1986)] and operates instead with the assumption that a neuroscientific theory of cognition will be a theory about cognitive mechanisms and not directly about behavior; cognitive descriptions of mental events will not be replaced by neural descriptions but may be reduced to this latter level of description, should such a day arrive. Classical neuropsychological research operated within a medical model framework mostly uninformed by cognitive or linguistic theory, and certainly unconcerned with the objective of developing a computationally explicit account of language processing. The syndromes that were correlated to anatomical sites for clinico-pathological analyses were based on impoverished notions of language processing using clinically derived, common sense classification schemes for language impairments (e.g. Benson 1985, Damasio 1981, Kertesz 1985. The symptoms that comprised the syndromes were grossly nonanalytic behavioral categories such as poor repetition, poor auditory language comprehension, poor naming ability, and so forth--behavioral conglomerates that are subserved by highly complex sets of cognitive and linguistic mechanisms. There are several reasons for rejecting this approach as a framework within which to explore the structure of the cognitive/linguistic mechanisms that subserve language processing and their relationship to the brain. However, before briefly presenting the details of this critical analysis I should like to consider one major accomplishment that has been achieved through research carried out within this framework.Despite the serious limitations of this approach, what little is known about the functional neuroanatomy for language has come to us principally through clinico-pathological correlations for the aphasias. Although it has been known at least since the time of Hippocrates (ca 400 B.c.) that insult to the brain may result in disturbances of the language faculty, it was not until the detailed analysis of Broca, Wernicke, Charcot, Lichtheim, Dejerine, and others in the second half of the nineteenth century that a firm foundation was laid for relating language processes to the brain. Indeed by the end of that century French and German neurologists had described all the major aphasia syndromes at a level of detail that seemed to allow little opportunity for improvement. These investigators, under the influence of Gall's phrenological hypothesis, which proposed that distinct areas of the cerebral cortex subserve different cognitive facult...

Morpho-lexical Representations in Naming

“…The evidence from our results is not conclusive in this regard; nevertheless, it is consistent with the pattern of speech errors in normal speakers (e.g. Garrett, 1982;Stemberger, 1985) and the pattern of omissions and substitutions of in ectional af xes in aphasic patients (see Caramazza, 1988, for a review).…”

Orthography Influences the Perception of Speech in Alexic Patients

“…Additionally, it appears that this system is accessible via auditory input, although it may not be accessible via visual input. This brings us to a critical distinction regarding the nature of orthographic knowledge: Is it best described as a single orthographic lexicon that subserves both reading and spelling (Burt & Tate, 2002), or as separate input and output lexica (Caramazza, 1988)? This question can also be framed in terms of whether reading and spelling depend on the same processing components or not (Tainturier & Rapp, 2001).…”

“…This question can also be framed in terms of whether reading and spelling depend on the same processing components or not (Tainturier & Rapp, 2001). For example, neuropsychological evidence has been used to endorse the view of separate, modality-specific lexical components involved in the recognition (input) and production (output) of written and spoken words (Caramazza, 1988). Others have argued that modality-specific access procedures are used for reading and spelling from a single orthographic processing system (Tainturier & Rapp, 2001).…”

Effects of grapheme-to-phoneme probability on writing durations

“…The socalled lexical route gives access to the spelling of whole words from long-term memory so it would be used when spelling familiar words. In contrast, the sublexical route or assembled route makes use of knowledge about the links between phonology and orthography and provides a phonologically plausible spelling for nonwords or low-frequency words (Caramazza, 1988;Tainturier & Rapp, 2001). Although the existence of both routes is almost undisputed, it is less clear whether or not their use is mutually exclusive during writing.…”