The role of nasals in reading: a normative study in French.

Dual-route models of reading assume that reading can be done in two ways. A most common lexical route, on the one hand, allows regular and irregular words to be read while a second sublexical route allows nonwords and novel words to be read. A graphemic processing stage in sublexical reading is assumed to assemble the individual letters of a word or a nonword into multiletter graphemes prior to grapheme-phoneme conversion. The purpose of this study was to determine whether vowel/nasal clusters required as much time to be processed asvowel/vowel and consonant/consonant clusters in sublexical nonword reading in French. Results indicate that nonwords that contain vowel/nasal clusters are read significantly faster than nonwords comprising vowel/vowel and consonant/consonant clusters. Furthermore, nonwords that contain single-letter graphemes are read significantly faster than nonwords comprising vowel/nasal clusters and nonwords comprising vowel/vowel and consonant/consonant clusters. These results taken as a whole support the idea that nasals act as diacritic marks rather than being processed by means of a graphemic parsing procedure.

Two different dysgraphic syndromes in a regular orthography, spanish.

In opaque orthographies, such as English and French, three central dysgraphic syndromes have been described: surface dysgraphia, phonological dysgraphia, and deep dysgraphia. Writing breakdown patterns reveal that spelling can proceed by phoneme-to-grapheme conversion, or by a more direct or lexical approach. Ardila et al. (1989, 1991) claim that for Spanish speakers a lexical strategy for reading and writing is not an option due to the regularity of the orthography of this language. In this study we report two clear cases of dysgraphia in Spanish, one of surface dysgraphia and another of phonological dysgraphia, where a dissociation between lexical and sublexical writing can be observed, thus contradicting Ardila's position.

Writing impairment in schizophasia: two case studies.

Two case studies were conducted of patients suffering from paranoid schizophrenia with glossomanic schizophasia. Their dictation-taking performance was assessed via a comprehensive standardized neuropsychological test battery following a protocol specifically designed for the purpose (Lecours, 1996.). The patients' performance was compared with normative data from the general population. The results show that the patients committed graphemic paragraphias, that is, they replaced target graphemes with others representative of the corresponding phoneme (ph and f for/f/, in French) or with graphemes representative of a similar phoneme (v for/f/). These errors suggest that components of a cognitive model of writing are dysfunctional.

[Acquired dyslexias and dysgraphias under the prism of cognitive neuropsychology: a model for the Spanish language]. / Las dislexias y disgrafías adquiridas bajo el prisma de la neuropsicología cognitiva: un modelo para la lengua castellana.

The present paper discusses the different clinical manifestations of acquired disorders of reading and writing from a neurocognitive viewpoint. Based on a specific functional architecture of reading and writing--a cognitive model; presented as well--the different syndromes of acquired dyslexias and dysgraphias, that have been described in the specialized literature during the last 25 years, will be reviewed. The different pathologies are distributed along three different functional axes: a plurimodal component, including the semantic system, for the description of peripheric disorders of reading and writing; a lexical block which is justified by the findings in patients with surface dyslexia/dysgraphia; and a third, sublexical component, in order to illustrate the different functional impairments in phonological dyslexia/dysgraphia. Following the description of syndromes due to selective "functional lesions", we discuss deep dyslexia/dysgraphia, a syndrome due to multiple functional lesions. All of the syndromes will be justified and discussed with respect to the different components of the functional architecture presented and are based on cases of the literature and personal observations. Concluding remarks will evaluate the new insights gained by the presented functional arquitecture in relation to other cognitive models for the analysis of reading aloud and writing to dictation of single words.

The role of sublexical graphemic processing in reading.

Dual-route models of reading postulate the existence of two separate mechanisms: The lexical route allows words to be recognized in their holistic form, and the sublexical route proceeds by converting the written sublexical entities of a word or a nonword into their corresponding phonological equivalents. Sublexical reading is assumed to require three stages of processing: graphemic parsing, graphophonemic conversion, and phoneme blending. This study provides evidence in favor of the existence of a graphemic parsing process which occurs prior to grapheme-phoneme conversion. A group of normal subjects read nonwords which contained multiletter graphemes significantly more slowly than graphemically simple nonwords. These results, best interpretable in the context of a recent dual-route model of reading, confirm previous data obtained in pathology which suggest the functional independence of this cognitive procedure.

Las dislexias y disgrafías adquiridas bajo el prisma de la neuropsicología cognitiva: un modelo para la lengua castellana / Dyslexias and dysgraphies acquired under the prism of cognitive neuropsychology: a model for the Castillian language

En este artículo, siguiendo el enfoque nacido con las ciencias cognitivas, se discuten las distintas patologías dentro del campo de las dislexias y las disgrafías adquiridas. Basado en un modelo cognitivo, una arquitectura funcional -presentada también-, se abarcan los distintos síndromes que se han descrito en la literatura especializada durante los últimos 25 años. Las distintas patologías se presentan en tres bloques cognitivos: un bloque plurimodal para los trastornos periféricos (dentro del cual también se consideran las alteraciones semánticas); un bloque léxico, cuya funcionalidad es evidente a partir de la dislexia/disgrafía de superficie, y un bloque subléxico que sirve para detallar los trastornos subyacentes a la dislexia/disgrafía fonológica. Una vez descritos los problemas concretos, debidos a lesiones funcionales selectivas, se discuten los trastornos múltiples, la dislexia/disgrafía profunda. En todos los casos, se justifican plenamente muchos de los componentes del modelo basándose en casos reales. Finalmente, como conclusiones, se evalúan las aportaciones novedosas de esta arquitectura funcional en relación con otros modelos cognitivos para el análisis de la lectura en voz alta y la escritura al dictado de palabras aisladas. (AU)

Structural correlates of cognitive deficits in a selected group of patients with Alzheimer's disease.

OBJECTIVE: The objective of this study was to correlate the densities of neurofibrillary tangles (NFTs) and senile plaques (SPs) in 10 patients with Alzheimer's disease (AD) with comprehensive neuropsychological data obtained within 1 year of death. BACKGROUND: Clinicopathologic studies in AD have been essentially limited to correlate neuropathologic data with severity of dementia. Very few studies have addressed the correlations between distribution of lesions and specific cognitive deficits. This is partly due to the limitation imposed by the interval between the last neuropsychological evaluation and death. METHODS: Ten patients with a postmortem diagnosis of AD, with a mean age at death of 80.4+/-6.6 years and a mean duration of symptoms of 5.6+/-2.9 years, were selected for the study. All of these patients were submitted to neuropsychological testing within 1 year of death, including 17 tests assessing memory, language, visuoperceptual, visuospatial, and constructional abilities as well as limb praxis. The neuropathologic study was performed using a modified Bielschowsky technique. Mean densities of SPs and NFTs were determined in the hippocampal formation (CA1, subiculum, and parasubiculum) and in six neocortical areas (midfrontal, orbitofrontal, cingulum, fusiform gyrus, superior and inferior parietal cortices). Statistical correlations were determined between cognitive scores and SP and NFT densities. RESULTS: For NFTs, significant correlations emerged only between tangle density in CA1 and visuoperceptual scores. For SP density values, significant correlations were found between visuoperceptual tests and lesions in the subiculum and in the fusiform gyrus, significant correlations were found between language scores and SPs in the superior parietal cortex and between visuospatial deficits and lesions in the superior parietal cortex and fusiform gyrus. CONCLUSIONS: SPs in specific brain areas displayed a good correlation with the cognitive deficits detected in this selected group of AD patients. The association of fusiform gyrus and superior parietal lobule involvement with visuoperceptual and visuospatial deficits, respectively, is in agreement with current knowledge of the anatomic basis of visual processing.

The contribution of attentional mechanisms to an irregularity effect at the graphemic buffer level.

This study analyzes acquired dysgraphia observed in a French-speaking woman. The results point to an impairment of the graphemic buffer, i.e., the processing stage where abstract orthographic representations are temporarily stored while planning the written production. However, the spelling errors were more frequent in the irregular than in the regular words. A qualitative analysis of the errors in the irregular misspelled words showed that, in general, these were not "regularization" errors, but rather the same characteristics as the phonologically implausible errors found in the regular words, such as letters substitutions, deletions, additions, and transpositions. Furthermore, in a list of regular and irregular words of same length and graphemic structure, the errors not only tended to concentrate on the irregularity itself but also tended to be more frequent elsewhere in the irregular words compared to the regular words. These finding are discussed in terms of a post-lexical sensitivity to irregular spelling. It is also shown that when focusing attention on the irregularity becomes necessary, this can cause a detriment to the surrounding graphemic constituents. Interaction between attentional resources and processing of orthographic representations at the graphemic buffer level is considered.

Educational level and neuropsychological heterogeneity in dementia of the Alzheimer type.

We retrospectively assessed the data from 24 patients with dementia of the Alzheimer type (DAT) who underwent comprehensive neuropsychological evaluations in order to determine whether there is a relationship between neuropsychological heterogeneity and educational level. Postmortem neuropathological examination results were made available for seven cases, confirming the diagnosis of DAT. Thirteen patients had < or = 8 years of schooling (less educated subgroup), and the other 11 had > or = 8 years (higher educated subgroup). There were no significant differences between the two subgroups regarding age and duration of symptoms. Performance within each subgroup was compared with that of a specific set of education-matched elderly controls. In the less educated subgroup, 10 patients evidenced a homogeneous pattern of cognitive impairment, with all cognitive areas being similarly affected. Conversely, 10 higher educated patients had at least one cognitive area relatively preserved in comparison with the others, characterizing a heterogeneous pattern of impairment. These data suggest that a high level of education may lead to a greater capacity to compensate for neuronal damage and determines specific patterns of cognitive impairment in DAT.

Longitudinal study of basal cortisol levels in healthy elderly subjects: evidence for subgroups.

A group of 51 healthy elderly volunteer subjects participated in a 3- to 6-year longitudinal study of basal cortisol levels. Once per year basal cortisol levels were examined using hourly sampling over a 24-h period. Analyses of three cortisol measures (last measure obtained, mean cortisol levels across years, and the cortisol slope) revealed that the slope of the regression line measuring cortisol levels at each year was the most predictive measure of cortisol secretion over the years in this elderly population. Cortisol levels were shown to increase with years in one subgroup, to decrease in another, and to remain stable in a third. The age of the subjects was not related to either cortisol levels or to the pattern of change in cortisol secretion over years. Free and total cortisol levels were highly correlated and the groups did not differ with regard to plasma corticosteroid binding globulin. No group differences were observed for weight, height, body mass index, pulse, blood pressure and glucose. However, significant group differences were reported for plasma triglycerides levels as well as high density lipoproteins levels. Positive correlations were reported between the obsession/compulsion subscale of the SCL-90 questionnaire and the cortisol slope of subjects. Finally, previously reported group differences in neuropsychological performance are summarized. Thus, there exists considerable variation in hypothalamo-pituitary-adrenal function amongst aged humans. These results are consistent with recent animal studies showing the existence of subpopulations of aged rats which differ in hypothalamo-pituitary-adrenal activity and cognitive efficiency.

Influence of affective words on lexical decision task in major depression.

In cognitive science, lexical decision task is used to investigate visual word recognition and lexical access. The issue of whether or not individuals who are depressed differ in their access to affectively laden words and specifically to words that have negative affect was examined. Based on some aspects of the Resource Allocation Model (Ellis), it was postulated that patients suffering from depression take more time to recognize items from an affective-loaded list. In order to compare their behavior in a lexical decision task, patients suffering from depression and healthy controls were studied. We hoped to find an interaction between the mood state of subjects and the categories (affective or neutral) of words. Two groups of right-handed adults served as subjects in our experiment. The first group consisted of 11 patients suffering from depression (mean age: 40.2; sd: 6.8). All of this group met the DSM-III-R and the Research Diagnostic Criteria for major depressive disorder. Severity of their disease was rated using the 24-item Hamilton Depressive Rating Scale. All patients suffering from depression were without psychotropic medication. The control group was composed of 24 subjects (mean age: 32.7; sd: 7.9). A depressive word-list and a neutral word-list were built and a computer was used for the lexical-decision task. A longer reaction time to detect the non-word stimuli (F1,33 = 11.19, p < 0.01) was observed with the patients by comparison to the normal subjects. In the analysis of the word stimuli, a group by list interaction (F1,33 = 7.18, p < 0.01) was found.(ABSTRACT TRUNCATED AT 250 WORDS)

Basal cortisol levels and cognitive deficits in human aging.

A group of 19 healthy elderly subjects previously shown to differ in terms of their cortisol levels over a 4 year period were administered a neuropsychological test battery assessing memory, attention, and language. Correlational analyses performed on various corticosteroid measures showed that the slope of the change in cortisol levels over time predicted cognitive deficits in this elderly population. Aged subjects showing a significant increase in cortisol levels with years and with high current basal cortisol levels were impaired on tasks measuring explicit memory and selective attention when compared to aged subjects presenting either decreasing cortisol levels with years or increasing cortisol levels with moderate current basal cortisol levels. We further showed that subjects presenting a decrease in cortisol levels with years performed as well as young healthy subjects with regard to cognitive performance. Thus, impaired cognitive performance was associated with recent evidence of hypothalamic-pituitary-adrenal (HPA) dysregulation and elevated basal cortisol levels. These results are consistent with recent animal studies showing the existence of subpopulations of aged rats that differ in HPA activity and cognitive performance. Finally, the pattern of cognitive results related to the cortisol history of subjects is in agreement with a role played by the hippocampus in age-related HPA dysfunction and cognitive performance.

Two cases of deep dyslexia in unilingual hispanophone aphasics.

This paper addresses the interaction between a particular cognitive property inherent to the human brain, i.e., the capacity to learn how to process written information in a manner such that reading words aloud can become a standard aspect of overt behavior, and some of the culture-linked characteristics of the written codes invented by the species. First, the paper reiterates that the Spanish written code is transparent to the point of entailing full graphophonemic conversion, i.e., reading behavior is possible without access to one's memory of written words (to one's "logographic lexicon"). The Ardila claim (Ardila, 1991; Ardila, Rosselli, & Pinzon, 1989) that certain clinical forms of acquired reading disorders which have been reported to occur among various cultural subgroups do not occur among unilingual readers of Spanish is then summarized. This is followed by two brief case reports of acquired aphasia in native speakers and fluent readers of Spanish; prototypical "deep dyslexia" was documented to exist in both cases (Ruiz & Ansaldo, 1990). The Ardila claim is thereafter assessed by reference to the notions of surface, phonological, and deep dyslexia; parameters such as educational background are taken into account in this discussion.

Unexpected reading dissociation in a Brazilian "nisei" with crossed aphasia.

There is an increased interest in reading impairments in the Japanese language, due to its particular writing system which includes two different scripts, Kanji (logograms) and Kana (phonograms). Reading dissociations between Kanji and Kana have been described, showing that each system is processed differently by the cerebral hemispheres. We describe the case of a 68 year old Brazilian "nisei" (i.e. born from Japanese parents) who had knowledge of both Japanese and Portuguese. He presented an ischemic stroke affecting the right hemisphere and subsequently developed a Broca's aphasia and an unexpected reading dissociation, with an impairment in Kana reading comprehension and a good performance in Kanji and in Portuguese. These findings suggest that the patient's right and left hemispheres have assumed opposite roles not only for oral but also for written language decodification.

Jules Dejerine and his interpretation of pure alexia.

Dejerine's interpretation of pure alexia is routinely mentioned in all neuropsychological textbooks, yet the details of his account and the evidence on which it is based have never been subjected to a critical analysis. We provide such an evaluation in this paper, summarizing the behavioral data that Dejerine presented in his now famous case report and the theoretical framework he adopted to explain the phenomenon of alexia without agraphia. We also provide a link between Dejerine's work and current hypotheses on the nature of the syndrome.

[Heterogeneity of cognitive profiles in dementias of the Alzheimer type: theoretical aspects and clinical consequences]. / Hétérogénéité des profils cognitifs dans les démences de type Alzheimer: aspects théoriques et conséquences cliniques.

Presently, Alzheimer's disease can only be diagnosed with the coexistence of clinical symptoms and the presence of neuropathological alterations. Thus, in the absence of pre mortem biological markers, cognitive deficits form the starting point and the basis of inclusion criteria on which the clinician relies in order to make a putative diagnose of dementia of the Alzheimer type (DTA). Cognitive deficits should thus be accurately described through neuropsychological testing since it is essential to identify the cognitive deterioration patterns of the patients--in terms of selective impairment of cognitive functions--as well as the evolution of these patterns. Regarding this issue, the classical teaching of the Geneva school has proposed a homogeneous deterioration of the aphasic-apraxicagnosic syndrome into four stages. However, recent work does not support this hypothesis. On the contrary, these studies tend to show the presence of heterogeneity in neuropsychological manifestations of the disease. The aim of the present paper is to provide a critical review of this topic through a brief survey of the classical work and research that have recently been conducted. An analysis of the possible candidates responsible for the existence of this heterogeneity of cognitive profiles is presented. Finally, theoretical implications and clinical repercussions are discussed.