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A R Lecours

Publications and source records attributed to A R Lecours.

At least 55 records · Page 3Linked to original sources
PubMed1980

A binary articulatory production classification of English consonants with derived difference measures.

English consonants were classified according to six binary articulatory variables. Differences between the members of each possible consonant pair were quantified and the overall difference between each consonant and all other consonants was calculated. The consonant difference measures were found to be significantly related to children's substitution errors and to account for 56% of the variance in Templin's (1957) data on normal consonant acquisition. Similar measures calculated from the distinctive feature classifications of Chomsky and Halle (1968) and Singh and Singh (1976) accounted for less than one third of this amount. These findings suggest the potential utility of the present classification for the analysis of articulated speech.

Articulation Disorders↗
PubMedDate not supplied

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.

Adrenal Glands↗
PubMedDate not supplied

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.

Humans↗
PubMedDate not supplied

Proportional localization system for anatomical interpretation of cerebral computed tomograms.

The existence of individual variations in size and shape of the human brain constitutes a problem for the anatomical interpretation of brain reconstructed images obtained from scanning devices; it is, for example, responsible for most of the inaccuracies in reading CT scans. One way to account for these variations is to use a proportional localization system. In the 1960s a group of neurosurgeons developed such a system based on two pivotal intracerebral structures, the anterior and the posterior commissures; they published an atlas consisting of horizontal, coronal, and sagittal brain sections interpreted in the proportional system. The atlas also included standard proportional brain schemes based on anatomical and radiological studies on large numbers of individuals. In this article we report a target localization experiment that we carried out to determine if this atlas could be used as a reference for a more accurate interpretation of CT and, eventually, of positron emission tomography (PET) and nuclear magnetic resonance (NMR) scans. Ten radiopaque small targets were inserted through the skull in the cortex of three cadavers; head CT was performed, and the atlas was used for predicting the cortical location of the targets seen on the CT images: The predictions were confirmed. These results strongly support the use of the proportional atlas for the interpretation of CT as well as of PET and NMR scans.

Anatomy, Artistic↗
PubMedDate not supplied

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.

Adult↗
PubMedDate not supplied

[Neuropsychologic function of the depressive patient. A lexical decision investigation in major depression].

According to the Resource Allocation Model, it is logical to think that emotional mood states modulate the allocation of capacity, most cognitive tasks require some allocation of capacity, and in many instances there is a positive correlation between effort and memory. In cognitive science, the experimental paradigm of lexical decision task is used to investigate visual words recognition and lexical access. According to the Resource Allocation Model, we postulated that depressed patients take more time to recognize items from an affective loaded list. In order to compare their behavior in lexical decision task in this study, depressed patients 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. This kind of interaction is expected to figure among the cognitive markers of depression. Two groups of right-handed adults served as subjects in our experiment. The subjects were living in the north west region of Quebec. The first group consisted of 11 depressed patients (mean age: 40.2; SD: 6.8). All of them met the DSM III criteria for major depressive disorder and the RDC. Patients were rated using the 24-item Hamilton Depression Rating Scale (HDRS). All depressed patients were without medications. The control group was composed with 24 subjects (mean age: 32.7; SD: 7.9). We built a depressive word-list (Mood-list) and a neutral word-list (Neutral-list) and used a computer for the lexical-decision task. We noted a significant interaction [F(1.33) = 10,035, p < 0.001] between the subjects group (depression vs control) and the words category (Moodlist vs Neutral-list).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

[Verbal abilities of normal adults submitting to an aphasia linguistic protocol].

A language test protocol for aphasia in French-speaking patients was drawn up recently by workers in Toulouse and Montreal. The protocol has been applied to sixty hospitalized sciatica patients of the same age range and socio-cultural level as the average population of aphasics in our department. Only one of the normal patients passed the test without any mistakes. The number and nature of the mistakes are studied statistically in relation to age, sex and socio-cultural level.

Adolescent↗