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X Seron

Publications and source records attributed to X Seron.

At least 19 recordsLinked to original sources
PubMed1992

Images of numbers, or "When 98 is upper left and 6 sky blue".

Some people declare that they possess a personal visual representation of numbers: some automatically "see" the numbers they are confronted with in a precise location in a structured mental space, others "associate" specific colours with given numbers. Such visuo-spatial representations of numbers were first described by Galton in 1880 but have since received little attention from psychologists. It is the aim of this article to describe these mental representations and discuss their role in number processing. The authors first review Galton's observations, and then present their own. Finally, they discuss the relevance of these visuo-spatial representations in relation to contemporary debates on number representation and calculation.

Adult↗
PubMed1991

Dot counting by brain damaged subjects.

In this study, we examine how brain damaged adults (aphasics, right-brain lesioned subjects (RBD), and demented subjects) perform a basic education skill: determining the cardinality of different sets of objects (dots). The RBD subjects encountered more difficulty with the spatial correspondence components of the task (correct pointing to the dots), while the aphasics experienced more difficulty with the verbal components (the production of the correct number-word sequence). The deficit evidenced by the demented patients was less systematic. However, qualitative analyses of patients' behavior suggested an organization that tended to minimize the impact of their cognitive deficits on the object-counting task, and an analysis of their counting indicates that the basic counting principles proposed by Gelman (1982) and Fuson (1988) may be preserved.

Aphasia↗
PubMed1988

Aphasia and personality.

A critical review of the data in the literature and their interpretations is given. There are three main lines of interpretation: --The neuropsychological point of view interprets personality disorders as a reaction to the language deficit; --the anatomical point of view tries to relate personality disorders to the location and extent of brain lesions; --the historical point of view links personality disorders to the pre-morbid personality. All of them seem to have shortcomings and to be based at least in part on inadequate scientific methods including the principle problems of psychologically testing aphasics, of not having pre-morbid personality tests or using tests which are developed outside the field of neuropsychology. We suggest the development of multifactorial approaches which take into account biological, sociological and psycho-individual variables in an interactive way.

Adaptation, Psychological↗
PubMed1988

The operativity effect in naming: a re-analysis.

According to Howard Gardner (1973), operativity, i.e. the extent to which it is possible to act with or upon an object, influences picture naming by aphasic subjects. In the present study, this influence is analysed with three purposes: (1) to replicate the Gardner's observation, (2) to avoid methodological biases and to extend the analyses, and (3) to look for alternative explanations. Sixty-four pictures corresponding to high- and low-frequency nouns rated as high or low in operativity were presented to 18 aphasic subjects. Frequency and operativity were found to significantly affect naming performance. More particularly, fewer semantic paraphasias were observed in confrontation with operative items and fewer phonemic paraphasias in the production of frequent nouns. However, the influence of operativity on the reduction of errors disappeared when age-of-acquisition and picture familiarity were introduced as co-variables. These dimensions were found to be better predictors of aphasic performance than operativity.

Adult↗
PubMed1987

Right hemisphere language processing: lateral difference with imageable and nonimageable ambiguous words.

Influence of imageability on hemispheric processing difference is studied in a lexical decision task with semantic priming. Homographs and ambiguous words were biased according to the prime toward their low or high imageable meanings and unilaterally presented in the visual field. A right visual field (RVF) superiority was observed; it was nonsignificant for the high imageable (HI) meaning but significant for the low imageable (LI) meaning of the ambiguous words. Thus the results seem to favor a bilateral hemispheric representation of HI words and a unilateral left representation of LI words. Theoretical implications of the results are discussed to the various models of ambiguous word access processing.

Adolescent↗
PubMed1986

Aphasics' sensitivity to contextual appropriateness conditions for pragmatic indicators.

Twenty normal and twenty aphasic subjects were tested for their understanding of implicit meanings of the French adverbs même (even), aussi (also), and surtout (mainly). Their sensitivity to the contextual appropriateness conditions of such items was analyzed in a multiple-choice paradigm requiring them to select from three figures the one which was best described by a sentence like "Show me the figure that is même (aussi, surtout) red." A global quantitative comparison indicates that aphasics' performance was inferior to that of the normal controls. Yet, the analysis of individual responses allowed the identification of three different subgroups of aphasics: the first produced responses identical to the normals' responses; the second seemed to ignore the adverb and systematically selected the figure with the highest amount of the asserted color; and the third produced responses identical to the normals' responses for surtout but had difficulties with même or aussi. As concerns the relationship between aphasics' performance and their scores on literal language comprehension tests, the data favor the dissociation between literal and pragmatic factors in comprehension. Finally, no clear relationship was observed between aphasia type and aphasics' performance, although three points are noted in the discussion: (1) all the conduction aphasics performed like normals, (2) among the Broca's aphasics, the one with the clearest agrammatic verbal output produced responses similar to those of the normals, and (3) there was no anomic patient in the second subgroup.

Adult↗
PubMed1986

On fluency measures in aphasic speech.

This study was conducted with two purposes. First, to examine the extent to which fluency measures are affected by conditions of speech production. The speech of an unselected sample of 18 aphasic subjects was collected in two situations: conversation and description of short picture stories. Words were uttered at a reduced rate in the story descriptions, which were also characterized by a greater use of verbs. However, the ranking of the subjects on the different measures of fluency was correlated in the two situations. The second aim was to analyze the relationship between different fluency measures: mean silence duration, speech tempo, subjective evaluation of fluency, and the use of grammatical morphemes. Rankings of the subjects on these measures were compared. The different indicators of fluency were positively correlated with each other. Moreover, clinical evaluations of fluency by Belgian and American clinicians were correlated with the objective measures. However, fluency measures did not correlate with the percentage of content words. Thus, reduction of fluency did not seem to be related to a selective loss of function words.

Adolescent↗
PubMed1985

Syntactical knowledge in a case of agrammatism: evidence from transcoding Roman and Arabic numerals.

The ability of an aphasic subject with agrammatism in both comprehension and production to transcribe quantities from Roman numerals to Arabic and the reverse was investigated. Systematic errors in the transcoding processes were observed that could not be accounted for by the peculiarities of the two ideographic coding systems or by difficulties with direct transcoding rules. The results are discussed in the framework of the current debate on preserved/impaired hierarchical syntactical knowledge of agrammatic subjects. The findings paralleled the results of previous studies on the transcoding skills of agrammatics from/to alphabetic numerals to/from digital forms. In the case of this particular patient, it is therefore tentatively concluded in favor of preserved syntactical knowledge.

Adult↗
PubMed1984

From 2 to two: an analysis of a transcoding process by means of neuropsychological evidence.

This study investigates the abilities of aphasic subjects to transcode numbers from the digital code into the alphabetic code. The subjects' performances are considered first as dependent on general structural parameters such as item length or due to general behavioral impairments such as serial ordering disturbances. The second analysis focuses on typical aphasic errors in the processing of lexical primitives that are not specific to the linguistic material used in this transcoding task, such as literal or morphemic paragraphias . The third analysis considers the erroneous transcriptions as resulting from partial or inappropriate use of a subset of normal transcoding strategies. The latter approach proves to be particularly powerful in accounting for the systematicity of the errors produced by aphasic subjects. The result thus appear to be relevant to the study of the psycholinguistic mechanisms responsible for performing such transcoding tasks by normals.

Adult↗
PubMed1984

Semantic errors reconsidered in the procedural light of stack concepts.

The purpose of this paper is to demonstrate the relevance of the stack concept in neuropsycholinguistics, a stack being a file with serially ordered elements. Number names (one, two, three, . . .) and the names of the days in the week may be viewed in this way. In a stack structure, any element is identified by two pieces of information: the particular stack to which it belongs and its position within that stack. Two experiments are reported that demonstrate a double dissociation. A deep dyslexic patient with agrammatism was found to sort stack elements on the basis of identity of position-within-stacks, while a fluent aphasic with semantic verbal paraphasias used another criterion, grouping together the items of the same stack. First revealed when handling number names, the two psycholinguistic procedures are also shown to be differentially operative with other linguistic material. Introducing the stack concept thus permits a procedural reinterpretation of some "semantic confusions," particularly but not exclusively those dealing with quantities.

Adult↗
PubMed1983

A case of prosopagnosia with some preserved covert remembrance of familiar faces.

This paper presents the detailed analysis of a case of prosopagnosia in a 54-year-old male farmer following bioccipital vascular disease. In-depth clinical investigations confirmed the diagnosis of prosopagnosia and revealed the absence of any associated defect, except for a slight aspecific disturbance of the short-term memory. Further study of this case indicated that the trouble was not concerned with the class of complex visual stimuli, was not even concerned with facial expressions or unknown faces, was not a perceptual defect, but was related mainly to the operation of individualization. The memory hypothesis was thus retained and supported. Moreover, exploration of the difficulty indicated that the deficiency was limited to defective access to conscious information concerning faces and information associated with these faces (name, context, etc.), effectively stored in memory.

Agnosia↗
PubMed1983

From 4 to four. A supplement to 'From three to 3'.

The psycholinguistic investigation of the ability of patients with Broca's and Wernicke's aphasia to transcode quantities from the ideographic digital coding system to alphabetical numerals parallels our previous study on the reverse transcoding task. The results support the generality of differential impairment of syntactic/nonsyntactic skills in Broca's and Wernicke's aphasia.

Aphasia↗
PubMed1982

Decoding paralinguistic signals: effect of semantic and prosodic cues on aphasics' comprehension.

A matching task between sentences voiced with joyful, angry, or sad intonation and pictures of facial expressions representing the same emotions is proposed to 27 aphasics and 20 normal subjects. Semantic contents are either meaningless, neutral, or affectively loaded. In the affective-meaning condition, content is redundant with prosody or conflicting with it. Results are 1. a greater number of nonprosodic choices in the aphasic group; 2. an identical influence of the congruence/conflict variable on aphasic and control subjects; 3. an identical influence of the semantic content of the conflict sentences on both groups. Aphasic impairment is interpreted as purely quantitative, since affective semantic content influences the decoding of the sentences.

Adult↗
PubMed1982

[Right hemisphere lesion and directional indication in a visuoconstructive task].

We test the hypothesis that the divergences between Hecaen and Assal (1970) and Gianotti et al (1977) as regards the efficiency of indications supplied together with drawings to patients with unilateral lesion are due to the topological or directional nature of these indicators. We submit subjects with cerebral damage to a test involving copying cubes and non-significant drawings by opposing these two types of indication and also resorting to the procedure of Pillon and Lhermitte (1978). The results demonstrate that the topological or directional character of the indicators used can account for the differences between these two sets of findings. Finally, the results tend to show that the left hemisphere basically controls the manipulatory or executive side of the visuo-constructive task, whilst the right takes over its executive and perceptive aspects in conjunction.

Apraxias↗