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Emmanuel Stip

Publications and source records attributed to Emmanuel Stip.

8 recordsLinked to original sources
PubMed2003

Sleep architecture and its clinical correlates in first episode and neuroleptic-naive patients with schizophrenia.

The goal of the present study was to characterize sleep organization in first episode and neuroleptic-naive patients with schizophrenia and to evaluate relationships between those sleep parameters and clinical symptoms. Eleven patients with acute schizophrenia never treated with neuroleptics were compared to 11 healthy controls. Sleep stages and phasic events (sleep spindles and rapid-eye-movements during REM sleep (REMs) were visually identified. Clinical symptoms were assessed using the Brief Psychiatric Rating Scale (BPRS). Compared to controls, patients with schizophrenia had difficulty initiating sleep, decreased stage 4 duration, reduced rapid eye movement (REM) sleep latency, and normal sleep spindles and REMs densities. Positive symptoms correlated negatively with REM sleep latency. The BPRS total score correlated negatively with REM sleep duration and REMs density. The present results indicate that first episode and neuroleptic-naive patients with schizophrenia have difficulties initiating, but not maintaining, sleep. These results also confirm that the duration of stage 4 and REM sleep latency are reduced in first episode and neuroleptic-naive patients with schizophrenia. The fact that measures of REM sleep correlate with clinical scales of schizophrenia suggests that REM sleep physiology shares common substrates with symptoms of this disease.

Acute Disease↗
PubMed2003

Procedural learning in schizophrenia after 6 months of double-blind treatment with olanzapine, risperidone, and haloperidol.

RATIONALE: First generation antipsychotics induce extrapyramidal motor symptoms (EPS), presumably through dopamine D(2) receptor blockade at the dorsal striatum. This may also produce impairment of cognitive processes, such as procedural learning, that are dependent on this region. Haloperidol and, to a lesser extent, risperidone, are active in the dorsal striatum and may induce EPS and impairment of procedural learning. In contrast, the prototypical second-generation antipsychotic, clozapine, is less active in the dorsal striatum and does not induce EPS or impair procedural learning. Olanzapine is pharmacologically similar to clozapine and has a low incidence of EPS induction. OBJECTIVES: To assess the hypothesis that olanzapine would not have a deleterious effect on procedural learning. METHODS: Thirty-nine subjects with early phase schizophrenia were randomly assigned to double blind treatment with haloperidol, risperidone, or olanzapine. They were administered the Tower of Toronto test at an unmedicated baseline and again following 6 weeks and 6 months of treatment. RESULTS: Procedural learning, defined as the improvement observed between two blocks of five trials of the Tower of Toronto, was preserved after 6 weeks of all three treatments but showed a substantial decline after 6 months of treatment with haloperidol or risperidone. CONCLUSIONS: These data are consistent with the differential activity of the three medications in dorsal striatum structures and suggest that the advantages of olanzapine over haloperidol and risperidone in relation to extrapyramidal syndromes may also generalize to procedural learning. The results also suggest that the procedural learning disadvantages of haloperidol and risperidone accrue slowly but are apparent after 6 months of treatment.

Adolescent↗
PubMed2003

A Canadian multicenter trial assessing memory and executive functions in patients with schizophrenia spectrum disorders treated with olanzapine.

Serial verbal learning task (explicit long-term memory) and verbal fluency (generation of a response) are tests that are usually severely impaired in schizophrenia. Despite the growing literature supporting the clinical efficacy of olanzapine, psychiatrists still question its cognitive consequences. This study assessed the efficacy of olanzapine on neurocognitive functioning. Patients (N = 134) meeting diagnostic criteria for schizophrenia, schizophreniform, or schizoaffective disorders began an 8-week, open-label olanzapine treatment at a dose of 5 mg/d, which was increased to 10 mg/d after 1 week. Daily dosage was subsequently adjusted between 5 and 20 mg/d based on individual clinical status. All previous antipsychotics were tapered and discontinued during the first 2 weeks of the study. Neuropsychologic assessments were carried out at baseline and at 4 and 8 weeks. Explicit long-term memory was assessed with the Rey Auditory-Verbal Learning Test: the average immediate recall score significantly improved (P < 0.001), as did the delayed recall score (P < 0.001). The average total score on category fluency improved from 34.6 words at baseline to 37.6 words at end point (P < 0.0001). Time on both Trail A and B making tasks significantly decreased (P < 0.0001). Lack of a control arm makes it impossible to exclude a practice effect as an explanation for the enhanced cognitive performance, although the Word List Recall test represents one of the better resources to avoid a practice effect. After switching to olanzapine, there was a statistically significant improvement of cognitive function in the 3 main domains tested and no significant worsening of any memory or executive function measure.

Acoustic Stimulation↗
PubMed2003

Clozapine, quetiapine and olanzapine among addicted schizophrenic patients: towards testable hypotheses.

Although life prevalence of substance use disorders among patients with schizophrenia is close to 50%, few studies have been carried out to date to identify an integrated pharmacological treatment for this comorbidity. So far, the most promising results, that we report here, have been obtained with clozapine. To a lesser extent, quetiapine and olanzapine, both clozapine analogues, have also shown promising results. Further to these observations, the present paper critically reviews the advantages associated with clozapine, quetiapine and olanzapine, and their relevance to the treatment of addiction among schizophrenic patients. Six characteristics seem to distinguish clozapine, quetiapine and olanzapine from the first-generation antipsychotics: (1) acting preferentially on the reward system, these second-generation antipsychotics (mainly clozapine and quetiapine) induce almost no extrapyramidal symptoms; (2) quickly dissociating from D(2), theses drugs (mainly clozapine and quetiapine) seem not to induce dysphoria, unlike conventional antipsychotics like haloperidol;(3) these drugs (mainly clozapine) seem more effective in the treatment of negative symptoms than conventional antipsychotics; (4) because of a diversified activity on several serotoninergic and noradrenergic receptors, these drugs positively alter mood, which does not seem to be the case with conventional antipsychotics, except for flupenthixol; (5) these drugs have a positive impact on cognition, which is not the case with the first-generation antipsychotics; (6) unlike conventional antipsychotics, these drugs seem to have a moderate affinity for 5-HT(3), the receptor on which ondansetron, an anti-craving medication, acts.

Affect↗
PubMed2003

Mild procedural learning disturbances in neuroleptic-naive patients with schizophrenia.

This study investigated whether drug-naive patients with schizophrenia present procedural learning disturbances, given that this function is known to involve the striatum and that structural abnormalities of the striatum have been described in these patients. Eleven neuroleptic-free schizophrenic patients were compared with 11 healthy control subjects on a visuomotor procedural learning task (the Mirror Drawing Test). Average performance and learning rate did not differ between the two groups. However, schizophrenia patients were lower in learning smoothness (the consistency with which performance improves from trial to trial), which would indicate difficulty in benefiting from past experience to perform better on a current task. Because low smoothness has recently been found to be associated with striatal dysfunction, these results might indicate a premature dysfunction of the striatum in young drug-naive patients with schizophrenia. However, this dysfunction is not severe enough to prevent learning.

Adult↗
PubMed2002

Happy birthday neuroleptics! 50 years later: la folie du doute.

Given that we are celebrating the 50th birthday of neuroleptics introduction in psychiatry, the author proposes to take a look at certain results related to therapeutic practice. After a brief chronological literature review of the clinical practices and theoretical models that have controlled drug treatment of schizophrenia, the author presents a critical review of four meta-analyses. Since Delay, Deniker and Harl's initial report, the story of neuroleptics comprises several periods. In 1963, the hyper-dopaminergic theory of psychoses was proposed. Another period began with models mainly based on the serotonin/dopamine relative blockade receptor hypothesis. More recently, a new framework to understand the differential effect of antipsychotics is related to the appropriate modulation (e.g., fast dissociation) of the D2 receptor alone. The concept of atypicality has become a new vista for research and to market new compounds. However, after 50 years of neuroleptic drugs, are we able to answer the following simple questions: Are neuroleptics effective in treating schizophrenia? Is there a difference between atypical and conventional neuroleptics? How do the efficacy and safety of newer antipsychotic drugs compare with those of clozapine? Actually, the answers yielded by these simple questions by meta-analysis should elicit in us a good deal of humility. If we wish to base psychiatry on evidence-based medicine, we run a genuine risk in taking a closer look at what has long been considered fact. Each psychiatrist must continue to be critical, sceptical, optimistic (not overoptimistic) and to learn in order to integrate the positive aspects of our growing knowledge base.

Antipsychotic Agents↗
PubMed2002

Cerebral activity associated with auditory verbal hallucinations: a functional magnetic resonance imaging case study.

Among the many theories that have been advanced to explain the mechanism by which auditory verbal hallucinations (AVH) arise, 2 that have received a degree of empirical support are: the hypothesis that AVHs arise from misinterpreted inner speech and the proposal that they arise from aberrant activation of the primary auditory cortex. To test these hypotheses, we were fortunate to be able to study the interesting and rare case of a woman with schizophrenia who experienced continuous AVH which disappeared when she listened to loud external speech. Functional magnetic resonance imaging (fMRI) was used to measure the patient's brain activity in the temporal and inferior frontal regions during the AVHs and while the she was listening to external speech. The brain activity of a matched control subject was also recorded under the same experimental conditions. AVHs were associated with increased metabolic activity in the left primary auditory cortex and the right middle temporal gyrus. Our results suggest a possible interaction between these areas during AVHs and also that the hypotheses of defective internal monitoring and aberrant activation are not mutually exclusive. Potential limitations to the generalization of our results are discussed.

Adult↗