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C Passerieux

Publications and source records attributed to C Passerieux.

12 recordsLinked to original sources
PubMed2003

Functional analysis of the deficit in semantic context processes in schizophrenic patients: an event-related potentials study.

AIM: Schizophrenic patients exhibit a deficit in the semantic context processing strategies which might be responsible for the language and communication disorders that are characteristic of this condition. The aim of our study was to identify the nature of the contextualization processes which are lacking in schizophrenic patients, by distinguishing between processes for the generation of expectations and processes of semantic integration. PATIENTS AND METHOD: Thirteen schizophrenic patients and 12 healthy controls performed two tasks: (a) a lexical decision task (LDT) with a highly structured sentence context and whose experimental characteristics made it possible to call strongly on predictive strategies, and (b) a LDT with classic semantic priming (the context being reduced to a single word). In this latter task, the small number of related words did not prompt the generation of expectations but instead called on the postlexical integration process. The event-related potentials (ERP) were recorded during the administration of the task. RESULTS AND CONCLUSION: In the sentence task, we observed a modulation in the N400 amplitude due to the presence of expectations both in the schizophrenic and control participants: predictable words evoked a small N400 amplitude compared to the non-predictable words. In contrast, in the simple (priming) task, the semantic link evoked an N400 amplitude modulation in the control group exclusively. Our results indicate that schizophrenics could be able to use context to activate expectations for the most highly predictable item, and that their deficit appears when the processing strategy is based on the integration of the context stored in working memory.

Adult↗
PubMed2002

Lexical decision tasks in depressive patients: semantic priming before and after clinical improvement.

This study was designed to evaluate the effect of semantic priming with a lexical decision task in 22 depressed patients (DSM-III-R, 1987) and 30 control subjects. These patients were evaluated twice: first when they arrived at the hospital, and secondly, after clinical improvement. Clinical improvement was evaluated using standard depression rating scales. A lexical decision task involving semantic relations (related vs. unrelated, e.g., apple-pear) was used to evaluate the processing of semantic information. The results showed that, for the first evaluation, the depressives presented similar semantic priming to control subjects. When we compared semantic priming in the first and the second passes, we observed that its amplitude was identical. The sole difference between the two passes concerns the global reaction time in the depressive group. This last result suggested that, with clinical improvement, the characteristic psychomotor retardation declines. One of the major results concerns the fact that severe depressive patients (first pass) exhibit normal semantic priming in a lexical decision task. These results indicate, in this clinical population, the preservation of controlled processes implicated in this lexical decision task.

Adult↗
PubMed1999

Fluency versus conscious recollection in category-production performance: the performance of schizophrenic patients.

The purpose of this study was to investigate the relative contribution in schizophrenics of automatic processes (fluency) and conscious processes (conscious recollection) for the control of preencoded material in category production tasks. In one condition (Exclusion condition), subjects were told specifically not to produce previously presented words during the category-production task. This condition was compared with a standard category-production task in which subjects were told to produce the six first words that came to mind for a semantic category (Inclusion condition). In the inclusion condition, the effects of conscious control and automatic processes operated in the same direction, whereas in the exclusion condition automatic influences and conscious control were opposed. A recognition task followed the category-production tasks. Since the exclusion condition required conscious control of encoded items, we hypothesized that schizophrenic patients would be less able than control subjects to avoid producing study list items. These results indicated that schizophrenics' performance differed from these of control subjects in the exclusion condition but not in inclusion condition. Recognition performance was similar in both the schizophrenic and the control groups. These results suggest a defective conscious control in schizophrenic patients and confirm the data from the literature on explicit memory in these patients.

Female↗
PubMed1998

Impairment of semantic categorization processes among thought-disordered schizophrenic patients.

OBJECTIVE: To explore semantic categorization strategies in patients with schizophrenia. METHOD: A short-term memory-recognition task that reveals the effects associated with categorization was created and applied to 2 groups of patients with schizophrenia and depression. RESULTS: Only the schizophrenic subgroup with formal thought disorder (measured using Andreasen's Thought, Language, and Communication [TLC] scale) exhibited a deficiency in semantic categorization strategies during the task. CONCLUSION: These results support the hypothesis of the impairment of the processes involved in the processing of contextual information in patients with schizophrenia who suffer from formal thought disorder.

Adult↗
PubMed1997

Heterogeneity in cognitive functioning of schizophrenic patients evaluated by a lexical decision task.

BACKGROUND: The disorganization pattern in schizophrenia, which involves formal thought disorders, is thought to be correlated with a deficit in integrative processes of contextual information. We tested the hypothesis that thought disordered schizophrenics, unlike non-though disordered schizophrenics, would present a deficit in the processing of the context during a task which involves these integrative processes. METHODS: A group of 22 schizophrenic patients diagnosed in accordance with DSM-III-R criteria and a group of 11 control subjects were compared using a semantic priming version of the lexical decision task. The experimental design used low-level structuration of verbal material to reveal the difficulty that schizophrenic patients encounter in using semantic regularities. RESULTS: A significant difference in priming effect was found between the three groups. Control subjects and non-thought disordered schizophrenics exhibit a priming effect for related word pairs when compared with unrelated pairs (respectively F(1,10) = 17.7; P < 0.002 and f(1,10) = 14.5; P > 0.003) but thought disordered schizophrenics did not (F(1,10) < 1; NS). CONCLUSIONS: This finding provides evidence for the cognitive heterogeneity of schizophrenic subjects. This absence of priming effect in thought-disordered schizophrenic subjects supports the hypothesis that these patients present a deficit in the post-lexical controlled information processing that permits the integration of semantic information.

Adult↗
PubMed1997

Syntactic and semantic processing in schizophrenic patients evaluated by lexical-decision tasks.

Two lexical-decision tasks with 500-ms stimulus-onset asynchrony were conducted with 34 schizophrenic patients. This group consisted of 24 schizophrenic patients with thought disorder (TD) and 10 schizophrenic patients without thought disorder (NTD), 14 psychiatric controls (depressive illness), 20 hospitalized controls, and 20 normal controls. One lexical-decision task with semantic relations (related vs. unrelated, Experiment 1) and 1 task with syntactic relations (congruent vs. incongruent; Experiment 2) were used to evaluate processing of different lexical information. In Experiment 1, although all control groups and NTD schizophrenic patients showed semantic priming, TD schizophrenic patients did not. In Experiment 2, all groups showed a significant syntactic effect. These findings provide evidence for an abnormality in semantic processing and the preservation of syntactic processing in TD schizophrenic patients, thus suggesting a deficit in the processing of semantic information under certain conditions when compared with normal syntactic processing.

Adult↗
PubMed1996

[Processing of contextual syntactic information in a decision making task in schizophrenic subjects].

OBJECTIVE: This research report studies how schizophrenic subjects process contextual syntactic information using a double-decision lexical task (deciding whether or not strings of letters form French words). Given the automatic nature of syntax, we are assuming the preservation of syntactical information processing in all the schizophrenic subjects, including those presenting thought disorder (TFP), which we name schizophrenic TPF+. METHOD: Twenty control subjects and 20 schizophrenic subjects (including 10 TFP+ schizophrenic subjects) participated in a double-decision lexical task containing syntactic errors. RESULTS: The results confirm our hypothesis because we show that all subjects (control and schizophrenic) are hampered in recognizing words when they contain grammatical errors. CONCLUSIONS: The results contrast with data on the processing of contextual semantic information by schizophrenic subjects, since the data in the literature conclude that there is an information-processing anomaly on the part of these patients. As a result, our study refutes the hypothesis of a generalized difficulty in the processing context by schizophrenic subjects.

Adult↗
PubMedDate not supplied

Can verbalization remedy the theory of mind deficit in schizophrenia?

Several studies provide convincing evidence of a specific deficit in the theory of mind (ToM) in some patients with schizophrenia. This ToM deficit consists of an inability to attribute relevant mental states to others, and studies suggest it has to be regarded as functional and remediable through the use of reinforced context processing. To investigate this, the present study compares the performances of 25 schizophrenics and 25 matched controls in a task exploring ToM before and after the introduction of verbal material into the task, initially conceived as nonverbal. All the controls and half of the schizophrenic subjects who did not initially perform at the best level remediated with verbalization, while 9 of the schizophrenics exhibited no remediation. These poor performers are characterized by a longer duration of illness. The cognitive plasticity and the characteristics of patients who do/do not remediate are discussed in the light of findings obtained with the Wisconsin Card Sorting Test. The clinical implication of these results is important since they suggest that some patients would benefit from cognitive rehabilitation in terms of their ability to attribute relevant mental states to others.

Adult↗
PubMedDate not supplied

[Formal thought disorders: French translation of the Thought, Language and Communication assessment scale].

This article proposes a french translation of Andreasen's Thought, Language and Communication (TLC) scale (Andreasen, 1979). This scale is widely used in current literature and remains a reference due to the fact that it has made it possible to establish a consensus with regard to formal thought disorders and has contributed to the operationalisation of the concept of dissociation. This scale consists of 18 items. Each item is clearly defined through the use of clinical examples, rated from 0 to 4 as a function of the intensity of the disorder (absent, slight, medium, severe, extreme). The interview conditions are also stated: free interview of minimum 10 minutes followed by a more structured interview. Some items of the TLC are taken directly from the SANS and SAPS. Their translation has been taken over from french translations already validated by Lecrubier and Boyer (1987). The others were translated within the department and have been verified by a native English speaker. The entirely of the translation has been verified by Andreasen. The metrological qualities of this french translation have been studied in a population of 107 schizophrenic patients who fulfilled all the DSM IV criteria: 73 males and 34 females, mean age 33.4 9 years, in or outpatients, all under neuroleptic treatment and all evaluated by an experienced clinician. Thirty one patients have been filmed to assess the interjudge reliability. The results indicate a high level of interjudge consistency (interclass correlation coefficient 0.96). The global score was 17 9.4. In the factorial analysis before rotation we observe a main factor that makes it possible to calculate a global score. The results of factor analysis of the TLC variables after rotation yield five factors that have an eigen value greater than 1. These five factors explain 66% of the variance. All items have a weight greater than 0.45. The first factor includes Poverty of content speech, Tangentiality, Derailment, Incoherence, Illogical thinking, Loss of goal and Perseveration. It reflects thinking disorganisation. The second factor includes Pressure of speech, Circumstantiality, Self reference and Poverty of speech (negative weight). This factor reflects verbal production. The third factor is composed of Clanging, Neologisms, Word approximation and Echolalia. This factor reflects verbal structure. The fourth factor is only composed of Stilted speech and the fifth one composed of Distractible speech and Blocking. These data have been compared to those reported in the literature: Andreasen in 1979 (113 patients: 32 suffering from manic disorder, 36 from depressive disorder and 45 schizophrenic disorder) and in 1986 (194 subjects: 94 controls, 25 suffering from manic disorder, 25 schizoaffective disorder and 50 schizophrenic patients), Harvey in 1992 (115 schizophrenic patients) and Peralta in 1992 (142 schizophrenic patients). Response levels for each item of the TLC french translation were very close to those found in the english versions. Differences in scores can be explained by clinical differences between populations studied. Factorial analyses also correspond well to such versions. In particular, after rotation, the three factorial subscores found representative of disorganisation, verbal production and verbal structure respectively are closed to those proposed by the english versions. In conclusion, the translation of Andreasen's Thought, Language and Communication (TLC) scale (Andreasen 1979) that we propose here therefore appears to exhibit metrological qualities sufficiently close to those reported in literature to permit its generalised use in France.

Adult↗
PubMedDate not supplied

[Communication disorders in schizophrenic patients. Cognitive explanation and clinical reconsideration].

The definition of schizophrenic patients communication disorders sets many problems (partly linked to the descriptive vagueness of the Bleuler mental dissociation syndrome) and leads today to give up those signals, considered as of little specification, for symptoms of easier definition. Nevertheless, french clinicians go on using the dissociation concept to make the diagnostic of schizophrenia, faithful to Bleuler teaching according to which the communication of these patients would be very specific. The object of this article is to take up with the Bleuler logic and to propose hypothesis of cognitive abnormalities that underlie the symptomatic expression of the communication troubles of these patients and point out, from these hypothesis, how a more specific rereading of the language, thought and communication disorders is possible. Two cognitive abnormalities are suggested by the literature data to explain some schizophrenic communication disorders, abnormalities which seem at least partly independent. The first one can be described in the terms of a model of action and brings down communication to its dimension of discursive action. The authors define it as a trouble of a mechanism of action supervision, of the action monitoring, or of the planning of discourse. The symptomatic expressions of this trouble may be described when the subject is under interview conditions soliciting it Examples of such clinical situations are given. The second abnormality may be described in the terms of the "Theory of Mind" and concern the difficulties of some schizophrenic patients to attribute mental states to their interlocuters. Here again, examples of clinical conditions are given, allowing us to investigate this abnormality.

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