jean Vion-Dury | Aix-Marseille University (original) (raw)
Papers by jean Vion-Dury
Psn-psychiatrie Sciences Humaines Neurosciences, 2019
Cet article tente de faire le point des differentes theories concernant le phenomene hypnotique, ... more Cet article tente de faire le point des differentes theories concernant le phenomene hypnotique, en partant du principe qu’il s’agit plus d’un fait anthropologique majeur que d’une simple modification psychologique ou de la conscience, tant le phenomene hypnotique est integre a une problematique sociale dans de nombreuses civilisations. C’est pourquoi, nous abordons la question de maniere epistemologique, sans prendre parti pour telle ou telle theorie et en essayant de degager ce que chacune d’entre elle apporte a la connaissance de ce phenomene complexe. Il apparait en realite que la multiplicite des theories relativise la force de chacune d’elle, et que, au bout du compte, il est bien difficile de proposer un schema d’ensemble coherent ou une theorie unificatrice de ce qu’est le phenomene hypnotique. De maniere simplifiee, deux cadres theoriques se font face : les approches psychologiques au sens large (psychologie cognitive, psychanalyse, psychologie sociale) et les approches phy...
A supposer même que toutes les questions scientifiques possibles soient résolues, les problèmes d... more A supposer même que toutes les questions scientifiques possibles soient résolues, les problèmes de la vie demeurent intacts. A vrai dire il ne reste plus aucune question; et c'est cela même la réponse 1. I) Introduction : la phénoménologie comme épistémologie. De nos jours, certains artistes, et/ou artistes-chercheurs, tous styles confondus, sont de plus en plus fascinés par les neurosciences. Peut-être recherchent-ils en elles l'explication de leur propre créativité, ou bien des « preuves scientifiques » capables de justifier ou d'asseoir une position objective à leur intense subjectivité, par ailleurs si riche, dans ce siècle de fer de la technique poussée à l'extrême, voire même, parfois, deshumanisante. Or il nous semble nécessaire de ne pas accepter cet état de fait sans préalablement avoir fait une critique épistémologique (mais non agiographique) des neurosciences, et plus particulièrement de la neuroesthétique, ce qui implique de mettre en doute le langage et les concepts véhiculés par ces disciplines. A notre sens une telle épistémologie peut être inspirée (mais pas seulement) par le regard de la phénoménologie. Car comme le dit Husserl, « Lorsque nous entrons dans les sciences naturelles pour vivre en elles, nous trouvons tout dans la mesure où elles ont atteint le stade de l'exactitude claire et compréhensible. Nous avons la certitude d'être en possession d'une vérité objective, démontrée par des méthodes sûres, méthodes qui atteignent réellement l'objectivité. Mais aussitôt que nous passons à la réflexion nous nous trouvons déroutés et confondus. Nous nous embrouillons dans de manifestes incompatibilités et même dans des contradictions… [la phénoménologie] a la tâche positive d'apporter la solution, par l'étude de l'essence de la connaissance, aux problèmes que renferme la corrélation entre la connaissance, le sens cognitif et l'objet de connaissance » 2. C'est dans cet esprit de critique de la connaissance que va se déployer l'argument de cet article. Dans cette dynamique de la critique de la connaissance et de son fondement, la phénoménologie s'intéresse à l'apparaître même des phénomènes. Un phénomène est « ce qui apparaît dans la conscience, ce qui est perçu, tant dans l'ordre physique que psychique… Se dit au sens le plus large de tous les faits constatés qui constituent la nature des sciences... Pour Kant, le phénomène est ce qui est « objet d'expérience possible », c'est à dire tout ce qui apparaît dans le temps ou l'espace, et qui manifeste des rapports déterminés par des catégories (c'est la réalité sensible)» 3. On doit différencier ainsi ce qu'est un fait (par exemple scientifique) de ce qu'est un phénomène : « un fait est en quelque sorte un phénomène arrêté, précis, déterminé, ayant des contours que l'on peut saisir et dessiner… le phénomène c'est le fait en mouvement, c'est le passage d'un fait à l'autre, c'est le fait qui se transforme d'instant en instant » (Janet cité dans Lalande 4). Ainsi la phénoménologie « est la science de l'expérience vécue par un « Je », elle traite de ce qui apparaît en tant que contenu de conscience (Bewusstseinsinhalt), non pas en ce sens que tout objet soit pour ainsi dire contenu dans la conscience mais au sens où quelque objet que ce soit est réduit à la sphère immanente de la conscience, c'està-dire comme phénomène" 5. Comme le dit Husserl, la phénoménologie est un « retour aux choses mêmes ». Un geste fondamental de la phénoménologie est l'épochè, c'est à dire la suspension du jugement de validité de l'évidence naturelle (habituelle), de la validité de ce qu'on nous dit de ce monde donné comme allant de soi, dans l'héritage même de tout ce qui nous a été transmis comme "vérités" à propos du monde.
Feuillets de Radiologie, 2005
Clinical use of brain monovoxel spectroscopy and spectroscopic imaging. H-MRS is a neurochemistry... more Clinical use of brain monovoxel spectroscopy and spectroscopic imaging. H-MRS is a neurochemistry sequence currently proposed by the manufacturers in MRI systems with a magnetic field higher than 1.5 Tesla. In spite of technical progress and its relevance in clinical investigation, H-MRS remains little used. Unfortunately, investigators find this technique difficult to perform. The aim of this article is to provide some help to the users who want to develop clinical spectroscopy (Single voxel Spectroscopy, and/or MRSI). We present proposals to facilitate MR spectrum acquisition, processing and data analysis.
Presse médicale (Paris, France : 1983), Jan 2, 1992
In conjunction with biopsy and Doppler studies, we analysed by high resolution proton NMR spectro... more In conjunction with biopsy and Doppler studies, we analysed by high resolution proton NMR spectroscopy the blood plasma of 22 heart transplant recipients. There was a significant variation in the glycosylated residues of proteins with the development of acute cardiac rejection. A more extensive study is underway to assess the sensitivity and specificity of this approach for the early diagnosis of acute cardiac rejection.
Annales de l'Institut Pasteur / Actualités, 1998
ABSTRACT
Neuroenhancement is an anglo-saxon concept concerning the use of stimulating psychotropic drugs b... more Neuroenhancement is an anglo-saxon concept concerning the use of stimulating psychotropic drugs by healthy subjects, outside any established medical indication or festive setting, to achieve an improvement of their mental functioning. In 2009, because of increasing requests for neuroenhancement in USA, the American Association of Neurology has published practical recommendations stating that "it is ethically permissible to prescribe medications for neuroenhancement" if a number of conditions is met. We present these ethical and psychopharmacological conditions ("the inverted U-Shape principle" in which cognitive performance is related to catecholamine levels and "the trade-off principle" to cognitive enhancement) through a clinical case of methylphenidate prescription in a healthy 24 years old medical student, preparing for the "examen classant national" (the French national ranking before postgraduate education). We then discuss anglo-saxon ethical context in which these recommendations have been proposed.
NMR in Biomedicine, 1993
Proton high-resolution MRS of human plasma allows the rapid detection, on the same spectrum, of m... more Proton high-resolution MRS of human plasma allows the rapid detection, on the same spectrum, of many compounds originating from different metabolic pathways. In this paper, we illustrate the modifications of the plasma metabolic profiles recorded by proton NMR spectroscopy in different classes of cancers. These modifications can be easily monitored with graphic aids such as 'star plots' which define for each type of cancer a particular pattern describing the most altered metabolic pathways. By using 'star plots' three types of metabolic patterns have been distinguished: (i) the 'inflammatory' pattern characterized by an increase of glycosylated moieties of glycoproteins; (ii) a 'lipid modified' pattern, characterized by various modifications occurring mainly in the lipid moieties detected by MRS; and (iii) a pattern which is often observed in sarcomas and mainly characterized by an alteration in the N-acetyl glucosamine/N-acetyl neuraminic acid ratio. This study demonstrates the ability of proton MRS of plasma to rapidly detect the occurrence of metabolic modifications brought about by cancer evolution or therapy.
Neurophysiologie Clinique/Clinical Neurophysiology, 2012
Emotions color in a singular way our everyday life and constitute important determinants of human... more Emotions color in a singular way our everyday life and constitute important determinants of human cognition and behavior. Emotional regulation is an essential process involved in neuropathophysiology and therapeutic efficacy in many psychiatric disorders. Yet, traditional psychiatric therapeutic has focused on symptomatic rather than neurophysiological criteria. Therefore, it was proposed to teach patients to modify their own brain activity directly, in order to obtain a therapeutic effect. These techniques, which are named neurofeedback, were originally developed using electroencephalography. Recent technical advances in fMRI enable real-time acquisition, and open opportunities to its utilization in neurofeedback. This seems particularly interesting in emotion regulation, which, at a neurofunctional level, lies on cortico-limbic pathways that, in great parts, were previously identified by traditional fMRI paradigms. This emotion regulation plays a central role in the etiopathogeny psychiatric, especially depressive and anxious, disorders. It is possible to devise new therapeutic strategies and research approach for addressing directly the neurophysiological processes of emotion regulation by integrating the neurofunctional activities of a subject. These prospects seem to be in line with the neurophenomenology project, which proposes to establish a link between subjective experiences and objective neurophysiological measures.
Magnetic Resonance in Medicine, 1999
Cerebral metabolism in six children with X-linked adrenoleukodystrophy (X-ALD) was studied using ... more Cerebral metabolism in six children with X-linked adrenoleukodystrophy (X-ALD) was studied using 1H magnetic resonance spectroscopy (MRS), and the status of the patients was monitored for evaluating disease progression. Spectra were abnormal even in patients with no cerebral impairment. Four different metabolic patterns were identified, and a metabolic classification of the disease was proposed, from grade 0 to grade III. The evolution of the disease toward grade II appears to be systematic, but many patients did not evolve from this grade to grade III, which is the metabolic mark of severe progressive forms. Metabolic data of X-ALD were processed using discriminant analysis, which provides a classification accuracy of 95.2%. Proton cerebral MRS together with discriminant analysis may be useful during the follow-up in X-ALD for monitoring the evolution of the disease and the effects of therapy.
Journal of Pharmaceutical Sciences, 1992
Small unilamellar liposomes containing fluorinated steroids (flumethasone and dexamethasone) were... more Small unilamellar liposomes containing fluorinated steroids (flumethasone and dexamethasone) were obtained. A physicochemical evaluation was conducted based on photon correlation spectroscopy (PCS) and fluorine-19 (IgF) nuclear magnetic resonance (NMR) spectroscopy compared with standard biochemical methods (HPLC). The PCS method provides a fast and adequate evaluation of some critical features of liposomes (size, physical stability). In addition, ''F NMR spectroscopy gives substantial information, in a nondestructive manner, on steroid behavior in the membrane upon encapsulation and also when the temperature of liposomes is increased. The combined spectroscopic approach proposed here might prove useful in (1) the management of liposomal formulation, especially in the documentation of physicochemical properties, (2) pharmaceutical control in the industrial production line, and (3) control preceding injection at the clinical site. Spectroscopic techniques might offer a complementary approach to classical biochemical methods in the evaluation of the properties of a liposomal formulation and could be usefully integrated into quality control procedures. Liposomes constitute a particular pharmaceutical formulation allowing significant modifications in the pharmacokinetic properties of a drug, such as its parenchymal delivery. Preparations of liposomes containing a fluorinated steroid (dexamethasone) have been recently proposed in topical1 and ocular2.3 drug administration. Therapeutic applications of liposomes require a rigorous quality control specific to this pharmaceutical form: vesicle size, encapsulation ratio, and kinetics of release constitute the main parameters which define a liposomal preparation. The usual biochemical evaluation of liposomes generally requires separation or destruction of vesicles, which are then analyzed in a sequential manner by chromatography, centrifugation, and radioactive or fluorescent labeling techniques.
Journal of Affective Disorders, 2014
Thought and language disturbances are crucial clinical features in Bipolar Disorders (BD), and co... more Thought and language disturbances are crucial clinical features in Bipolar Disorders (BD), and constitute a fundamental basis for social cognition. In BD, clinical manifestations such as disorganization and formal thought disorders may play a role in communication disturbances. However, only few studies have explored language disturbances in BD at a neurophysiological level. Two main Event-Related brain Potentials (ERPs) have been used in language comprehension research: the N400 component, elicited by incongruous word with the preceding semantic context, and the Late Positive Component (LPC), associated with non-specifically semantic and more general cognitive processes. Previous studies provided contradictory results regarding N400 in mood disorders, showing either preserved N400 in depression or dysthymia, or altered N400 in BD during semantic priming paradigm. The aim of our study was to explore N400 and LPC among patients with BD in natural speech conditions. ERPs from 19 bipolar type I patients with manic or hypomanic symptomatology and 19 healthy controls were recorded. Participants were asked to listen to congruous and incongruous complete sentences and to judge the match between the final word and the sentence context. Behavioral results and ERPs data were analyzed. At the behavioral level, patients with BD show worst performances than healthy participants. At the electrophysiological level, our results show preserved N400 component in BD. LPC elicited under natural speech conditions shows preserved amplitude but delayed latency in difference waves. Small size of samples, absence of schizophrenic group and medication status. In contrast with the only previous N400 study in BD that uses written semantic priming, our results show a preserved N400 component in ecological and natural speech conditions among patients with BD. Possible implications in terms of clinical specificity are discussed.
Investigative Radiology, 2002
RATIONALE AND OBJECTIVES. The neurotrophic effect of Xaliproden has been followed using sequentia... more RATIONALE AND OBJECTIVES. The neurotrophic effect of Xaliproden has been followed using sequential cerebral magnetic resonance imaging (MRI) in rats with vincristine-induced brain lesion as a model of Alzheimer disease. METHODS. Nineteen rats received an intraseptal injection of vincristine on day 0, followed by a daily gavage with either the vehicle (Tween-20 1%) (n ؍ 10) or Xaliproden (10 mg/kg) (n ؍ 9). Eight sham-operated controls received a daily gavage with either the vehicle (n ؍ 4) or Xaliproden (n ؍ 4). Brain MR imaging was performed at 4.7 T on a Biospec 47/30 MR system before surgery then 3, 7, 10, and 14 days after surgery. RESULTS. At day 3 following vincristine injection, an increase in MR signal intensity in the septum was observed on T2-weighted images. This increase was maximal at day 10, and remained stable until day 14. Daily treatment with Xaliproden delayed the appearance of hypersignals until day 7 and reduced by Ca. 50% the magnitude of the increase in signal intensity from day 10. No changes were observed in the hippocampus. CONCLUSION. Quantitative MRI objectifies noninvasively the neuroprotective effect of Xaliproden on rat brain anatomy.
International Journal of Cancer, 1990
Metabolic pathways of glucose utilization have been investigated in a human colon adenocarcinoma ... more Metabolic pathways of glucose utilization have been investigated in a human colon adenocarcinoma cell line (HT29) using carbon-I3 Nuclear Magnetic Resonance spectroscopy. HT29 cells were adapted to grow on a polystyrene beaded microcarrier and were perfused when attached to the beads in a specially designed NMR cell. Abnormalities in carbohydrate metabolism already observed in several cancer cells were studied in HT29 cells fed with (I-%)-enriched glucose. The cells were first perfused with a glucose-free medium for 2 hr in order to deplete the intracellular store of glycogen, and they were subsequently perfused with a medium containing enriched glucose at an initial concentration of 5.5 mM. Sequential I3CC-NMR spectra, recorded at 100.5 MHz (5 min accumulation), show that HT29 cells were able to utilize glucose through the glycolytic pathway while storing glucose as glycogen (glucose was utilized at a rate of 3.9 pmol/mg protein/ hr). The glycolytic activity determined by the amount of lactic acid produced was 4.6 pdmg proteidhr, corresponding to the formation of 1.2 lactic acid per glucose molecule. Glycogen accumulation corresponded to 16 pg/mg of protein. Treatment of HT29 with 10 nM vasoactive intestinal peptide (VIP) induced a transient decrease in the level of labelled glycogen to 50% of the initial value. Control level was recovered I 2 min after VIP loading.
Clinical Neurophysiology, 2013
In this letter, we propose, first, to summarize different methods to investigate sensory gating a... more In this letter, we propose, first, to summarize different methods to investigate sensory gating abnormalities in schizophrenia, and, second, to give some new ways to generate testable hypotheses in order to investigate one controversial topic in this field of clinical neurophysiology. These new ways are belong to the program of neurophenomenology that proposes to combine neurophysiological data (3rd person) with various empirical ways of describing first person experiences (Depraz et al., 2003). Indeed, deficit in sensory gating in schizophrenia was suggested by the now-classic phenomenological study of McGhie and Chapman (1961). In this study based on interviews, patients with schizophrenia reported being flooded by an overwhelming mass of sensory inputs combined with a heightened sensory perception, particularly in the auditory and visual modalities (McGhie and Chapman, 1961; Light and Braff, 2003). Since this work, there are two classical way to explore the sensory gating deficit in schizophrenia. The first is a ‘‘phenomenological’’ one with perceptual self-report scales inspired the McGhie and Chapman’s pioneer work. The second is an ‘‘electrophysiological’’ approach with Event Related Potential (ERP) method in a click-paired-stimulus (S1–S2) also known as conditioning-testing P50 paradigm (Light and Braff, 2003). The Structured Interview for Assessing Perceptual Anomalies (SIAPA) was the first self-report scale exploring sensory gating experience (Bunney et al., 1999). For the five sensory modalities 5-point Likert items were assessed on three dimensions: hypersensitivity, inundation/flooding, and selective attention to external usual stimuli. They reported a significantly greater prevalence of auditory and visual perceptual anomalies in patients with schizophrenia, when compared to control subjects (Bunney et al., 1999), and confirmed the results of McGhie and Chapman (1961). The recent article of Hetrick et al. (2012) offered a new reliable and valid scale to explore more precisely the phenomenological dimension of sensory gating. The Sensory Gating Inventory (SGI) consists in 36 items rated on a 6-point Likert scale. They reported that abnormal sensory gating experience relies upon modification in the modulation of percepts, including both the modulation of stimulus intensity and perceptual inundations (Hetrick et al., 2012). The modifications of the P50 component amplitude following a click-paired-stimulus (S1 and S2 separated optimally by 300 to 500 ms) are traditionally the auditory ERP method exploring sensory gating. P50 is a middle latency positive ERP component occurring around 50 ms after stimulation onset. After the second stimulus S2, the P50 amplitude is smaller compared to the response obtained after the first stimulus (S1) of the pair (down to half of the value) in healthy subjects contrary to schizophrenic patients (Adler et al., 1982). The P50 amplitude ratio between S2 and S1 responses commonly serves as a measure of the auditory gating. As this ratio is greater for schizophrenia patients than for healthy subjects, it was suggested that it might be an electrophysiological marker of deficient neural sensory gating in schizophrenia (Patterson et al., 2008). However, the link between abnormal phenomenological and electrophysiological dimensions of sensory gating is unclear in schizophrenia (Light and Braff, 2003). Indeed, Jin et al. (1998) did not find a relationship between abnormal phenomenological sensory gating experiences on auditory and visual items of the SIAPA and P50 electrophysiological sensory gating deficits. Thus, one important and controversial problem in this research area is whether the neurophysiological measure actually does reflect the phenomenon of interest. Recently, we proposed a new phenomenological way to explore sensory gating abnormalities in schizophrenia (Micoulaud-Franchi et al., 2012). Our experimental paradigm was to ask the participants to listen to calibrated non-verbal complex sounds and to evaluate (among other aspects) the ‘‘invasive’’ aspect of the sound by positioning a slider on a continuous linear scale (represented by a vertical bar) ranging between two numeric anchors located at the extremities from 0 (e.g. ‘‘not invasive’’) to 100 (e.g. ‘‘very invasive’’). This ‘‘invasive’’ aspect was explained as the ‘‘feeling of being flooded/inundated by real sounds’’ as denoted by an item in the SIAPA (Bunney et al., 1999). In contrast to Jin et al. results (1998), we found that the S2/S1 ratio was positively correlated with the invasive rating for non-verbal complex environmental sounds in schizophrenia (Micoulaud-Franchi et al., 2012). This preliminary result, which obviously needs to be confirmed in a larger population, was the first to highlight a relation between electrophysiological impairments in the sensory gating processes of irrelevant sensory inputs and phenomenological perceptual experience of inundation and flooding in this disease. Light and…
Calcified Tissue International, 1995
The values of in vivo TI relaxation time (T1) of phosphorus atoms of wrist bone have been measure... more The values of in vivo TI relaxation time (T1) of phosphorus atoms of wrist bone have been measured by phosphorus-31 magnetic resonance spectroscopy (MRS) in 65 menopausal women separated into three groups: (1) agematched women without any paraclinical or clinical osteoporosis; (2) patients with paraclinical osteoporosis detected only by dual photonic absorptiometry; and (3) women with clinical osteoporosis with vertebral fractures. No significant differences were found in T1 values in the presence of paraclinical or clinical osteoporosis as compared to control values. No relationships were found among the T1, the value of the Z-score, the value of bone mineral content, the age of patients, the number of their children, and the age of menopause. Phosphorus-31 magnetic resonance spectroscopy of the wrist fails to separate osteoporotic from nonosteoporotic women and cannot be clinically used at this time to perform a noninvasive diagnosis of osteoporosis.
Biochimie, 1992
Two-dimensional J-resolved and correlated 1H NMR spectra with complete water suppression have bee... more Two-dimensional J-resolved and correlated 1H NMR spectra with complete water suppression have been obtained to further characterize a metabolic pattern for normal and pathological human plasma samples. 1H COSY spectra have been recorded on plasma from 12 patients with cancer in order to check for the possible presence of fucose. Our results show that there is no evidence for the presence of fucosylated lipids in the plasma of these patients.
Biochimie, 1992
m High resolution NMR spectroscopy of physiological fluids provides quantitative, qualitative and... more m High resolution NMR spectroscopy of physiological fluids provides quantitative, qualitative and dynamic information on the metabolic status of the interstitial and plasma compartments under a variety of pathophysiological conditions. The simultaneous detection and quantitation by NMR spectroscopy of numerous compounds of the intermediary metabolism offers a new insight in the understanding of the milieu intdrieur. NMR spectroscopy of physiological fluids offers a unique way to define and monitor the global metabolic homeostasis in humans. The development of this analytical approach is still limited by the scarcity of pluridisciplinary teams able to fully exploit the wealth of information present on the NMR spectrum of a fluid. While application in pharmacology and toxicology is already established, the main areas of current development are cancer, hereditary metabolic disorders, organ transplantation and neurological diseases.
Archives de Pédiatrie, 1995
Annales Médico-psychologiques, revue psychiatrique, 2013
ABSTRACT Conventional electroencephalogram (EEG) is an essential non-invasive technique to determ... more ABSTRACT Conventional electroencephalogram (EEG) is an essential non-invasive technique to determine the physiological and functional brain status. EEG is worthy of interest (i) for the diagnosis of neurological diseases in psychiatric syndromes and (ii) for the monitoring of possible iatrogenic effects of some psychiatric treatments: electroconvulsive therapy (ECT), antipsychotics (particularly clozapine), lithium and tricyclic antidepressants. The purpose of this article is to provide a basic knowledge to psychiatrists about the EEG signal and its origin, the special techniques used in psychiatry and EEG vocabulary description, in order to precise the best prescriptions of it and to understand the reports in their daily clinical practice. The relevance of the conclusion of an EEG requires an electro-clinical confrontation that involves a good knowledge of psychiatry by neurophysiologists and a good knowledge of EEG by psychiatrists. This complementary approach associated with an easy EEG accessibility in psychiatry allows this examination to keep an essential place for quality of health care of patients with mental disorders.
Annales Médico-psychologiques, revue psychiatrique, 2013
É lé ments pour une histoire de l'é lectricité et du cerveau en psychiatrie. Applications thé rap... more É lé ments pour une histoire de l'é lectricité et du cerveau en psychiatrie. Applications thé rapeutiques de la stimulation externe et de l'enregistrement é lectrique en psychiatrie (Partie II) Element for a history of electricity and brain in psychiatry. Psychiatric therapeutic applications of external electrical brain stimulation and electrical brain recording (Part II
Psn-psychiatrie Sciences Humaines Neurosciences, 2019
Cet article tente de faire le point des differentes theories concernant le phenomene hypnotique, ... more Cet article tente de faire le point des differentes theories concernant le phenomene hypnotique, en partant du principe qu’il s’agit plus d’un fait anthropologique majeur que d’une simple modification psychologique ou de la conscience, tant le phenomene hypnotique est integre a une problematique sociale dans de nombreuses civilisations. C’est pourquoi, nous abordons la question de maniere epistemologique, sans prendre parti pour telle ou telle theorie et en essayant de degager ce que chacune d’entre elle apporte a la connaissance de ce phenomene complexe. Il apparait en realite que la multiplicite des theories relativise la force de chacune d’elle, et que, au bout du compte, il est bien difficile de proposer un schema d’ensemble coherent ou une theorie unificatrice de ce qu’est le phenomene hypnotique. De maniere simplifiee, deux cadres theoriques se font face : les approches psychologiques au sens large (psychologie cognitive, psychanalyse, psychologie sociale) et les approches phy...
A supposer même que toutes les questions scientifiques possibles soient résolues, les problèmes d... more A supposer même que toutes les questions scientifiques possibles soient résolues, les problèmes de la vie demeurent intacts. A vrai dire il ne reste plus aucune question; et c'est cela même la réponse 1. I) Introduction : la phénoménologie comme épistémologie. De nos jours, certains artistes, et/ou artistes-chercheurs, tous styles confondus, sont de plus en plus fascinés par les neurosciences. Peut-être recherchent-ils en elles l'explication de leur propre créativité, ou bien des « preuves scientifiques » capables de justifier ou d'asseoir une position objective à leur intense subjectivité, par ailleurs si riche, dans ce siècle de fer de la technique poussée à l'extrême, voire même, parfois, deshumanisante. Or il nous semble nécessaire de ne pas accepter cet état de fait sans préalablement avoir fait une critique épistémologique (mais non agiographique) des neurosciences, et plus particulièrement de la neuroesthétique, ce qui implique de mettre en doute le langage et les concepts véhiculés par ces disciplines. A notre sens une telle épistémologie peut être inspirée (mais pas seulement) par le regard de la phénoménologie. Car comme le dit Husserl, « Lorsque nous entrons dans les sciences naturelles pour vivre en elles, nous trouvons tout dans la mesure où elles ont atteint le stade de l'exactitude claire et compréhensible. Nous avons la certitude d'être en possession d'une vérité objective, démontrée par des méthodes sûres, méthodes qui atteignent réellement l'objectivité. Mais aussitôt que nous passons à la réflexion nous nous trouvons déroutés et confondus. Nous nous embrouillons dans de manifestes incompatibilités et même dans des contradictions… [la phénoménologie] a la tâche positive d'apporter la solution, par l'étude de l'essence de la connaissance, aux problèmes que renferme la corrélation entre la connaissance, le sens cognitif et l'objet de connaissance » 2. C'est dans cet esprit de critique de la connaissance que va se déployer l'argument de cet article. Dans cette dynamique de la critique de la connaissance et de son fondement, la phénoménologie s'intéresse à l'apparaître même des phénomènes. Un phénomène est « ce qui apparaît dans la conscience, ce qui est perçu, tant dans l'ordre physique que psychique… Se dit au sens le plus large de tous les faits constatés qui constituent la nature des sciences... Pour Kant, le phénomène est ce qui est « objet d'expérience possible », c'est à dire tout ce qui apparaît dans le temps ou l'espace, et qui manifeste des rapports déterminés par des catégories (c'est la réalité sensible)» 3. On doit différencier ainsi ce qu'est un fait (par exemple scientifique) de ce qu'est un phénomène : « un fait est en quelque sorte un phénomène arrêté, précis, déterminé, ayant des contours que l'on peut saisir et dessiner… le phénomène c'est le fait en mouvement, c'est le passage d'un fait à l'autre, c'est le fait qui se transforme d'instant en instant » (Janet cité dans Lalande 4). Ainsi la phénoménologie « est la science de l'expérience vécue par un « Je », elle traite de ce qui apparaît en tant que contenu de conscience (Bewusstseinsinhalt), non pas en ce sens que tout objet soit pour ainsi dire contenu dans la conscience mais au sens où quelque objet que ce soit est réduit à la sphère immanente de la conscience, c'està-dire comme phénomène" 5. Comme le dit Husserl, la phénoménologie est un « retour aux choses mêmes ». Un geste fondamental de la phénoménologie est l'épochè, c'est à dire la suspension du jugement de validité de l'évidence naturelle (habituelle), de la validité de ce qu'on nous dit de ce monde donné comme allant de soi, dans l'héritage même de tout ce qui nous a été transmis comme "vérités" à propos du monde.
Feuillets de Radiologie, 2005
Clinical use of brain monovoxel spectroscopy and spectroscopic imaging. H-MRS is a neurochemistry... more Clinical use of brain monovoxel spectroscopy and spectroscopic imaging. H-MRS is a neurochemistry sequence currently proposed by the manufacturers in MRI systems with a magnetic field higher than 1.5 Tesla. In spite of technical progress and its relevance in clinical investigation, H-MRS remains little used. Unfortunately, investigators find this technique difficult to perform. The aim of this article is to provide some help to the users who want to develop clinical spectroscopy (Single voxel Spectroscopy, and/or MRSI). We present proposals to facilitate MR spectrum acquisition, processing and data analysis.
Presse médicale (Paris, France : 1983), Jan 2, 1992
In conjunction with biopsy and Doppler studies, we analysed by high resolution proton NMR spectro... more In conjunction with biopsy and Doppler studies, we analysed by high resolution proton NMR spectroscopy the blood plasma of 22 heart transplant recipients. There was a significant variation in the glycosylated residues of proteins with the development of acute cardiac rejection. A more extensive study is underway to assess the sensitivity and specificity of this approach for the early diagnosis of acute cardiac rejection.
Annales de l'Institut Pasteur / Actualités, 1998
ABSTRACT
Neuroenhancement is an anglo-saxon concept concerning the use of stimulating psychotropic drugs b... more Neuroenhancement is an anglo-saxon concept concerning the use of stimulating psychotropic drugs by healthy subjects, outside any established medical indication or festive setting, to achieve an improvement of their mental functioning. In 2009, because of increasing requests for neuroenhancement in USA, the American Association of Neurology has published practical recommendations stating that "it is ethically permissible to prescribe medications for neuroenhancement" if a number of conditions is met. We present these ethical and psychopharmacological conditions ("the inverted U-Shape principle" in which cognitive performance is related to catecholamine levels and "the trade-off principle" to cognitive enhancement) through a clinical case of methylphenidate prescription in a healthy 24 years old medical student, preparing for the "examen classant national" (the French national ranking before postgraduate education). We then discuss anglo-saxon ethical context in which these recommendations have been proposed.
NMR in Biomedicine, 1993
Proton high-resolution MRS of human plasma allows the rapid detection, on the same spectrum, of m... more Proton high-resolution MRS of human plasma allows the rapid detection, on the same spectrum, of many compounds originating from different metabolic pathways. In this paper, we illustrate the modifications of the plasma metabolic profiles recorded by proton NMR spectroscopy in different classes of cancers. These modifications can be easily monitored with graphic aids such as 'star plots' which define for each type of cancer a particular pattern describing the most altered metabolic pathways. By using 'star plots' three types of metabolic patterns have been distinguished: (i) the 'inflammatory' pattern characterized by an increase of glycosylated moieties of glycoproteins; (ii) a 'lipid modified' pattern, characterized by various modifications occurring mainly in the lipid moieties detected by MRS; and (iii) a pattern which is often observed in sarcomas and mainly characterized by an alteration in the N-acetyl glucosamine/N-acetyl neuraminic acid ratio. This study demonstrates the ability of proton MRS of plasma to rapidly detect the occurrence of metabolic modifications brought about by cancer evolution or therapy.
Neurophysiologie Clinique/Clinical Neurophysiology, 2012
Emotions color in a singular way our everyday life and constitute important determinants of human... more Emotions color in a singular way our everyday life and constitute important determinants of human cognition and behavior. Emotional regulation is an essential process involved in neuropathophysiology and therapeutic efficacy in many psychiatric disorders. Yet, traditional psychiatric therapeutic has focused on symptomatic rather than neurophysiological criteria. Therefore, it was proposed to teach patients to modify their own brain activity directly, in order to obtain a therapeutic effect. These techniques, which are named neurofeedback, were originally developed using electroencephalography. Recent technical advances in fMRI enable real-time acquisition, and open opportunities to its utilization in neurofeedback. This seems particularly interesting in emotion regulation, which, at a neurofunctional level, lies on cortico-limbic pathways that, in great parts, were previously identified by traditional fMRI paradigms. This emotion regulation plays a central role in the etiopathogeny psychiatric, especially depressive and anxious, disorders. It is possible to devise new therapeutic strategies and research approach for addressing directly the neurophysiological processes of emotion regulation by integrating the neurofunctional activities of a subject. These prospects seem to be in line with the neurophenomenology project, which proposes to establish a link between subjective experiences and objective neurophysiological measures.
Magnetic Resonance in Medicine, 1999
Cerebral metabolism in six children with X-linked adrenoleukodystrophy (X-ALD) was studied using ... more Cerebral metabolism in six children with X-linked adrenoleukodystrophy (X-ALD) was studied using 1H magnetic resonance spectroscopy (MRS), and the status of the patients was monitored for evaluating disease progression. Spectra were abnormal even in patients with no cerebral impairment. Four different metabolic patterns were identified, and a metabolic classification of the disease was proposed, from grade 0 to grade III. The evolution of the disease toward grade II appears to be systematic, but many patients did not evolve from this grade to grade III, which is the metabolic mark of severe progressive forms. Metabolic data of X-ALD were processed using discriminant analysis, which provides a classification accuracy of 95.2%. Proton cerebral MRS together with discriminant analysis may be useful during the follow-up in X-ALD for monitoring the evolution of the disease and the effects of therapy.
Journal of Pharmaceutical Sciences, 1992
Small unilamellar liposomes containing fluorinated steroids (flumethasone and dexamethasone) were... more Small unilamellar liposomes containing fluorinated steroids (flumethasone and dexamethasone) were obtained. A physicochemical evaluation was conducted based on photon correlation spectroscopy (PCS) and fluorine-19 (IgF) nuclear magnetic resonance (NMR) spectroscopy compared with standard biochemical methods (HPLC). The PCS method provides a fast and adequate evaluation of some critical features of liposomes (size, physical stability). In addition, ''F NMR spectroscopy gives substantial information, in a nondestructive manner, on steroid behavior in the membrane upon encapsulation and also when the temperature of liposomes is increased. The combined spectroscopic approach proposed here might prove useful in (1) the management of liposomal formulation, especially in the documentation of physicochemical properties, (2) pharmaceutical control in the industrial production line, and (3) control preceding injection at the clinical site. Spectroscopic techniques might offer a complementary approach to classical biochemical methods in the evaluation of the properties of a liposomal formulation and could be usefully integrated into quality control procedures. Liposomes constitute a particular pharmaceutical formulation allowing significant modifications in the pharmacokinetic properties of a drug, such as its parenchymal delivery. Preparations of liposomes containing a fluorinated steroid (dexamethasone) have been recently proposed in topical1 and ocular2.3 drug administration. Therapeutic applications of liposomes require a rigorous quality control specific to this pharmaceutical form: vesicle size, encapsulation ratio, and kinetics of release constitute the main parameters which define a liposomal preparation. The usual biochemical evaluation of liposomes generally requires separation or destruction of vesicles, which are then analyzed in a sequential manner by chromatography, centrifugation, and radioactive or fluorescent labeling techniques.
Journal of Affective Disorders, 2014
Thought and language disturbances are crucial clinical features in Bipolar Disorders (BD), and co... more Thought and language disturbances are crucial clinical features in Bipolar Disorders (BD), and constitute a fundamental basis for social cognition. In BD, clinical manifestations such as disorganization and formal thought disorders may play a role in communication disturbances. However, only few studies have explored language disturbances in BD at a neurophysiological level. Two main Event-Related brain Potentials (ERPs) have been used in language comprehension research: the N400 component, elicited by incongruous word with the preceding semantic context, and the Late Positive Component (LPC), associated with non-specifically semantic and more general cognitive processes. Previous studies provided contradictory results regarding N400 in mood disorders, showing either preserved N400 in depression or dysthymia, or altered N400 in BD during semantic priming paradigm. The aim of our study was to explore N400 and LPC among patients with BD in natural speech conditions. ERPs from 19 bipolar type I patients with manic or hypomanic symptomatology and 19 healthy controls were recorded. Participants were asked to listen to congruous and incongruous complete sentences and to judge the match between the final word and the sentence context. Behavioral results and ERPs data were analyzed. At the behavioral level, patients with BD show worst performances than healthy participants. At the electrophysiological level, our results show preserved N400 component in BD. LPC elicited under natural speech conditions shows preserved amplitude but delayed latency in difference waves. Small size of samples, absence of schizophrenic group and medication status. In contrast with the only previous N400 study in BD that uses written semantic priming, our results show a preserved N400 component in ecological and natural speech conditions among patients with BD. Possible implications in terms of clinical specificity are discussed.
Investigative Radiology, 2002
RATIONALE AND OBJECTIVES. The neurotrophic effect of Xaliproden has been followed using sequentia... more RATIONALE AND OBJECTIVES. The neurotrophic effect of Xaliproden has been followed using sequential cerebral magnetic resonance imaging (MRI) in rats with vincristine-induced brain lesion as a model of Alzheimer disease. METHODS. Nineteen rats received an intraseptal injection of vincristine on day 0, followed by a daily gavage with either the vehicle (Tween-20 1%) (n ؍ 10) or Xaliproden (10 mg/kg) (n ؍ 9). Eight sham-operated controls received a daily gavage with either the vehicle (n ؍ 4) or Xaliproden (n ؍ 4). Brain MR imaging was performed at 4.7 T on a Biospec 47/30 MR system before surgery then 3, 7, 10, and 14 days after surgery. RESULTS. At day 3 following vincristine injection, an increase in MR signal intensity in the septum was observed on T2-weighted images. This increase was maximal at day 10, and remained stable until day 14. Daily treatment with Xaliproden delayed the appearance of hypersignals until day 7 and reduced by Ca. 50% the magnitude of the increase in signal intensity from day 10. No changes were observed in the hippocampus. CONCLUSION. Quantitative MRI objectifies noninvasively the neuroprotective effect of Xaliproden on rat brain anatomy.
International Journal of Cancer, 1990
Metabolic pathways of glucose utilization have been investigated in a human colon adenocarcinoma ... more Metabolic pathways of glucose utilization have been investigated in a human colon adenocarcinoma cell line (HT29) using carbon-I3 Nuclear Magnetic Resonance spectroscopy. HT29 cells were adapted to grow on a polystyrene beaded microcarrier and were perfused when attached to the beads in a specially designed NMR cell. Abnormalities in carbohydrate metabolism already observed in several cancer cells were studied in HT29 cells fed with (I-%)-enriched glucose. The cells were first perfused with a glucose-free medium for 2 hr in order to deplete the intracellular store of glycogen, and they were subsequently perfused with a medium containing enriched glucose at an initial concentration of 5.5 mM. Sequential I3CC-NMR spectra, recorded at 100.5 MHz (5 min accumulation), show that HT29 cells were able to utilize glucose through the glycolytic pathway while storing glucose as glycogen (glucose was utilized at a rate of 3.9 pmol/mg protein/ hr). The glycolytic activity determined by the amount of lactic acid produced was 4.6 pdmg proteidhr, corresponding to the formation of 1.2 lactic acid per glucose molecule. Glycogen accumulation corresponded to 16 pg/mg of protein. Treatment of HT29 with 10 nM vasoactive intestinal peptide (VIP) induced a transient decrease in the level of labelled glycogen to 50% of the initial value. Control level was recovered I 2 min after VIP loading.
Clinical Neurophysiology, 2013
In this letter, we propose, first, to summarize different methods to investigate sensory gating a... more In this letter, we propose, first, to summarize different methods to investigate sensory gating abnormalities in schizophrenia, and, second, to give some new ways to generate testable hypotheses in order to investigate one controversial topic in this field of clinical neurophysiology. These new ways are belong to the program of neurophenomenology that proposes to combine neurophysiological data (3rd person) with various empirical ways of describing first person experiences (Depraz et al., 2003). Indeed, deficit in sensory gating in schizophrenia was suggested by the now-classic phenomenological study of McGhie and Chapman (1961). In this study based on interviews, patients with schizophrenia reported being flooded by an overwhelming mass of sensory inputs combined with a heightened sensory perception, particularly in the auditory and visual modalities (McGhie and Chapman, 1961; Light and Braff, 2003). Since this work, there are two classical way to explore the sensory gating deficit in schizophrenia. The first is a ‘‘phenomenological’’ one with perceptual self-report scales inspired the McGhie and Chapman’s pioneer work. The second is an ‘‘electrophysiological’’ approach with Event Related Potential (ERP) method in a click-paired-stimulus (S1–S2) also known as conditioning-testing P50 paradigm (Light and Braff, 2003). The Structured Interview for Assessing Perceptual Anomalies (SIAPA) was the first self-report scale exploring sensory gating experience (Bunney et al., 1999). For the five sensory modalities 5-point Likert items were assessed on three dimensions: hypersensitivity, inundation/flooding, and selective attention to external usual stimuli. They reported a significantly greater prevalence of auditory and visual perceptual anomalies in patients with schizophrenia, when compared to control subjects (Bunney et al., 1999), and confirmed the results of McGhie and Chapman (1961). The recent article of Hetrick et al. (2012) offered a new reliable and valid scale to explore more precisely the phenomenological dimension of sensory gating. The Sensory Gating Inventory (SGI) consists in 36 items rated on a 6-point Likert scale. They reported that abnormal sensory gating experience relies upon modification in the modulation of percepts, including both the modulation of stimulus intensity and perceptual inundations (Hetrick et al., 2012). The modifications of the P50 component amplitude following a click-paired-stimulus (S1 and S2 separated optimally by 300 to 500 ms) are traditionally the auditory ERP method exploring sensory gating. P50 is a middle latency positive ERP component occurring around 50 ms after stimulation onset. After the second stimulus S2, the P50 amplitude is smaller compared to the response obtained after the first stimulus (S1) of the pair (down to half of the value) in healthy subjects contrary to schizophrenic patients (Adler et al., 1982). The P50 amplitude ratio between S2 and S1 responses commonly serves as a measure of the auditory gating. As this ratio is greater for schizophrenia patients than for healthy subjects, it was suggested that it might be an electrophysiological marker of deficient neural sensory gating in schizophrenia (Patterson et al., 2008). However, the link between abnormal phenomenological and electrophysiological dimensions of sensory gating is unclear in schizophrenia (Light and Braff, 2003). Indeed, Jin et al. (1998) did not find a relationship between abnormal phenomenological sensory gating experiences on auditory and visual items of the SIAPA and P50 electrophysiological sensory gating deficits. Thus, one important and controversial problem in this research area is whether the neurophysiological measure actually does reflect the phenomenon of interest. Recently, we proposed a new phenomenological way to explore sensory gating abnormalities in schizophrenia (Micoulaud-Franchi et al., 2012). Our experimental paradigm was to ask the participants to listen to calibrated non-verbal complex sounds and to evaluate (among other aspects) the ‘‘invasive’’ aspect of the sound by positioning a slider on a continuous linear scale (represented by a vertical bar) ranging between two numeric anchors located at the extremities from 0 (e.g. ‘‘not invasive’’) to 100 (e.g. ‘‘very invasive’’). This ‘‘invasive’’ aspect was explained as the ‘‘feeling of being flooded/inundated by real sounds’’ as denoted by an item in the SIAPA (Bunney et al., 1999). In contrast to Jin et al. results (1998), we found that the S2/S1 ratio was positively correlated with the invasive rating for non-verbal complex environmental sounds in schizophrenia (Micoulaud-Franchi et al., 2012). This preliminary result, which obviously needs to be confirmed in a larger population, was the first to highlight a relation between electrophysiological impairments in the sensory gating processes of irrelevant sensory inputs and phenomenological perceptual experience of inundation and flooding in this disease. Light and…
Calcified Tissue International, 1995
The values of in vivo TI relaxation time (T1) of phosphorus atoms of wrist bone have been measure... more The values of in vivo TI relaxation time (T1) of phosphorus atoms of wrist bone have been measured by phosphorus-31 magnetic resonance spectroscopy (MRS) in 65 menopausal women separated into three groups: (1) agematched women without any paraclinical or clinical osteoporosis; (2) patients with paraclinical osteoporosis detected only by dual photonic absorptiometry; and (3) women with clinical osteoporosis with vertebral fractures. No significant differences were found in T1 values in the presence of paraclinical or clinical osteoporosis as compared to control values. No relationships were found among the T1, the value of the Z-score, the value of bone mineral content, the age of patients, the number of their children, and the age of menopause. Phosphorus-31 magnetic resonance spectroscopy of the wrist fails to separate osteoporotic from nonosteoporotic women and cannot be clinically used at this time to perform a noninvasive diagnosis of osteoporosis.
Biochimie, 1992
Two-dimensional J-resolved and correlated 1H NMR spectra with complete water suppression have bee... more Two-dimensional J-resolved and correlated 1H NMR spectra with complete water suppression have been obtained to further characterize a metabolic pattern for normal and pathological human plasma samples. 1H COSY spectra have been recorded on plasma from 12 patients with cancer in order to check for the possible presence of fucose. Our results show that there is no evidence for the presence of fucosylated lipids in the plasma of these patients.
Biochimie, 1992
m High resolution NMR spectroscopy of physiological fluids provides quantitative, qualitative and... more m High resolution NMR spectroscopy of physiological fluids provides quantitative, qualitative and dynamic information on the metabolic status of the interstitial and plasma compartments under a variety of pathophysiological conditions. The simultaneous detection and quantitation by NMR spectroscopy of numerous compounds of the intermediary metabolism offers a new insight in the understanding of the milieu intdrieur. NMR spectroscopy of physiological fluids offers a unique way to define and monitor the global metabolic homeostasis in humans. The development of this analytical approach is still limited by the scarcity of pluridisciplinary teams able to fully exploit the wealth of information present on the NMR spectrum of a fluid. While application in pharmacology and toxicology is already established, the main areas of current development are cancer, hereditary metabolic disorders, organ transplantation and neurological diseases.
Archives de Pédiatrie, 1995
Annales Médico-psychologiques, revue psychiatrique, 2013
ABSTRACT Conventional electroencephalogram (EEG) is an essential non-invasive technique to determ... more ABSTRACT Conventional electroencephalogram (EEG) is an essential non-invasive technique to determine the physiological and functional brain status. EEG is worthy of interest (i) for the diagnosis of neurological diseases in psychiatric syndromes and (ii) for the monitoring of possible iatrogenic effects of some psychiatric treatments: electroconvulsive therapy (ECT), antipsychotics (particularly clozapine), lithium and tricyclic antidepressants. The purpose of this article is to provide a basic knowledge to psychiatrists about the EEG signal and its origin, the special techniques used in psychiatry and EEG vocabulary description, in order to precise the best prescriptions of it and to understand the reports in their daily clinical practice. The relevance of the conclusion of an EEG requires an electro-clinical confrontation that involves a good knowledge of psychiatry by neurophysiologists and a good knowledge of EEG by psychiatrists. This complementary approach associated with an easy EEG accessibility in psychiatry allows this examination to keep an essential place for quality of health care of patients with mental disorders.
Annales Médico-psychologiques, revue psychiatrique, 2013
É lé ments pour une histoire de l'é lectricité et du cerveau en psychiatrie. Applications thé rap... more É lé ments pour une histoire de l'é lectricité et du cerveau en psychiatrie. Applications thé rapeutiques de la stimulation externe et de l'enregistrement é lectrique en psychiatrie (Partie II) Element for a history of electricity and brain in psychiatry. Psychiatric therapeutic applications of external electrical brain stimulation and electrical brain recording (Part II