This file was created by the Typo3 extension sevenpack version 0.7.16 --- Timezone: CEST Creation date: 2024-04-24 Creation time: 22-57-45 --- Number of references 49 article 39 Dialogues in Clinical Neuroscience 2020 WKL accepted Jack RFoucher GeraldStöber article 40 Progress in Neuropsychopharmacology and Biological Psychiatry 2018 Schizophrenia as a single liability model was confronted to the multiple psychotic phenotypes model proposed by the Wernicke-Kleist-Leonhard school, focusing on two: periodic catatonia (PC) and cataphasia (C). Both are stable and heritable psychotic phenotypes with no crossed liability and are coming with the buildup of specific residual symptoms: impairment of psychomotricity for PC and a specific disorganization of thought and language in C. Regional cerebral blood flow (rCBF) was used as a biomarker. We attempted to refute the single phenotype model by looking at relevant and specific rCBF anomalies for PC and C, that would exceed anomalies in common relative to controls (CTR), i.e. looking for a double dissociation. Twenty subjects with PC, 9 subjects with C and 27 matched controls had two MRI QUIPSS-II arterial spin labeling sequences converted in rCBF. One SPM analysis was performed for each rCBF measurement and the results were given as the conjunction of both analysis. There was a clear double dissociation of rCBF correlates between PC and C, both being meaningful relative to their residual symptomatology. In PC: rCBF was increased in the left motor and premotor areas. In C: rCBF was decreased bilaterally in the temporo-parietal junctions. Conversely, in both (schizophrenia): rCBF was increased in the left striatum which is known to be an anti-psychotics’ effect. These evidences refuted the single schizophrenia model and suggested better natural foundations for PC and C phenotypes. They plead for further research on them and further research on naturally founded psychotic phenotypes. WKL; connect fileadmin/cep_files/Articles/A_double_dissociation_between_two_psychotic_phenotypes-Periodic_catatonia_and_cataphasia.pdf fileadmin/Cours/Psychopatho/Divers/A_Double_Dissociation/index.html Jack RFoucher Yi FanZhang MathildeRoser JulienLamy Paulo Loureirode Sousa SébastienWeibel PierreVidailhet OlivierMainberger FabriceBerna article 41 PLOS ONE 2018 Magnetic resonance imaging (MRI) shows slight spatial variations in brain white matter (WM). We used quantitative multi-parametric MRI to evaluate in what respect these inhomogeneities could correspond to WM subtypes with specific characteristics and spatial distribution. Twenty-six controls (12 women, 38 ±9 Y) took part in a 60-min session on a 3T scanner measuring 7 parameters: R1 and R2, diffusion tensor imaging which allowed to measure Axial and Radial Diffusivity (AD, RD), magnetization transfer imaging which enabled to compute the Macromolecular Proton Fraction (MPF), and a susceptibility-weighted sequence which permitted to quantify R2* and magnetic susceptibility (?m). Spatial independent component analysis was used to identify WM subtypes with specific combination of quantitative parameters values. Three subtypes could be identified. t-WM (track) mostly mapped on well-formed projection and commissural tracts and came with high AD values (all p < 10-18). The two other subtypes were located in subcortical WM and overlapped with association fibers: f-WM (frontal) was mostly anterior in the frontal lobe whereas c-WM (central) was underneath the central cortex. f-WM and c-WM had higher MPF values, indicating a higher myelin content (all p < 1.7 10-6). This was compatible with their larger ?m and R2, as iron is essentially stored in oligodendrocytes (all p < 0.01). Although R1 essentially showed the same, its higher value in t-WM relative to c-WM might be related to its higher cholesterol concentration. Thus, f- and c-WMs were less structured, but more myelinated and probably more metabolically active regarding to their iron content than WM related to fasciculi (t-WM). As known WM bundles passed though different WM subtypes, myelination might not be uniform along the axons but rather follow a spatially consistent regional variability. Future studies might examine the reproducibility of this decomposition and how development and pathology differently affect each subtype. Jack RFoucher OlivierMainberger JulienLamy MathieuSantin AlexandreVignaud MathildeRoser Paulo Loureirode Sousa article 38 Human Brain Mapping 2017 10 38 10 4966-4979 Our purpose was to validate a reliable method to capture brain activity concomitant with hallucinatory events, which constitute frequent and disabling experiences in schizophrenia. Capturing hallucinations using functional magnetic resonance imaging (fMRI) remains very challenging. We previously developed a method based on a two-steps strategy including (1) multivariate data-driven analysis of per-hallucinatory fMRI recording and (2) selection of the components of interest based on a post-fMRI interview. However, two tests still need to be conducted to rule out critical pitfalls of conventional fMRI capture methods before this two-steps strategy can be adopted in hallucination research: replication of these findings on an independent sample and assessment of the reliability of the hallucination-related patterns at the subject level. To do so, we recruited a sample of 45 schizophrenia patients suffering from frequent hallucinations, 20 schizophrenia patients without hallucinations and 20 matched healthy volunteers; all participants underwent four different experiments. The main findings are (1) high accuracy in reporting unexpected sensory stimuli in an MRI setting; (2) good detection concordance between hypothesis-driven and data-driven analysis methods (as used in the two-steps strategy) when controlled unexpected sensory stimuli are presented; (3) good agreement of the two-steps method with the online button-press approach to capture hallucinatory events; (4) high spatial consistency of hallucinatory-related networks detected using the two-steps method on two independent samples. By validating the two-steps method, we advance toward the possible transfer of such technology to new image-based therapies for hallucinations. https://www.ncbi.nlm.nih.gov/pubmed/28660668 ArnaudLeroy Jack RFoucher DelphinePins ChristineDelmaire PierreThomas MathildeRoser SLefebvre AliAmad ThomasFovet NematJaafari RenaudJardri article 37 Frontiers in Computer Neuroscience 2016 10 23 Exploring time-varying connectivity networks in neurodegenerative disorders is a recent field of research in functional MRI. Dementia with Lewy bodies (DLB) represents 20% of the neurodegenerative forms of dementia. Fluctuations of cognition and vigilance are the key symptoms of DLB. To date, no dynamic functional connectivity (DFC) investigations of this disorder have been performed. In this paper, we refer to the concept of connectivity state as a piecewise stationary configuration of functional connectivity between brain networks. From this concept, we propose a new method for group-level as well as for subject-level studies to compare and characterize connectivity state changes between a set of resting-state networks (RSNs). Dynamic Bayesian networks, statistical and graph theory-based models, enable one to learn dependencies between interacting state-based processes. Product hidden Markov models (PHMM), an instance of dynamic Bayesian networks, are introduced here to capture both statistical and temporal aspects of DFC of a set of RSNs. This analysis was based on sliding-window cross-correlations between seven RSNs extracted from a group independent component analysis performed on 20 healthy elderly subjects and 16 patients with DLB. Statistical models of DFC differed in patients compared to healthy subjects for the occipito-parieto-frontal network, the medial occipital network and the right fronto-parietal network. In addition, pairwise comparisons of DFC of RSNs revealed a decrease of dependency between these two visual networks (occipito-parieto-frontal and medial occipital networks) and the right fronto-parietal control network. The analysis of DFC state changes thus pointed out networks related to the cognitive functions that are known to be impaired in DLB: visual processing as well as attentional and executive functions. Besides this context, product HMM applied to RSNs cross-correlations offers a promising new approach to investigate structural and temporal aspects of brain DFC. https://www.frontiersin.org/articles/10.3389/fncom.2016.00060/full MarionSourty LaurentThoraval DanielRoquet Jean-PaulArmspach Jack RFoucher FrédéricBlanc article 36 Neuroimage Clinical 2016 2 16-22 Purpose: Locked-in syndrome and vegetative state are distinct outcomes from coma. Despite their differences, they are clinically difficult to distinguish at the early stage and current diagnostic tools remain insufficient. Since some brain functions are preserved in locked-in syndrome, we postulated that networks of spontaneously co-activated brain areas might be present in locked-in patients, similar to healthy controls, but not in patients in a vegetative state. Methods: Five patients with locked-in syndrome, 12 patients in a vegetative state and 19 healthy controls underwent a resting-state fMRI scan. Individual spatial independent component analysis was used to separate spontaneous brain co-activations from noise. These co-activity maps were selected and then classified by two raters as either one of eight resting-state networks commonly shared across subjects or as specific to a subject. Results: The numbers of spontaneous co-activity maps, total resting-state networks, and resting-state networks underlying high-level cognitive activity were shown to differentiate controls and locked-in patients from patients in a vegetative state. Analyses of each common resting-state network revealed that the default mode network accurately distinguished locked-in from vegetative-state patients. The frontoparietal network also had maximum specificity but more limited sensitivity. Conclusions: This study reinforces previous reports on the preservation of the default mode network in locked-in syndrome in contrast to vegetative state but extends them by suggesting that other networks might be relevant to the diagnosis of locked-in syndrome. The aforementioned analysis of fMRI brain activity at rest might be a step in the development of a diagnostic biomarker to distinguish locked-in syndrome from vegetative state. connect http://www.sciencedirect.com/science/article/pii/S2213158216301012?via%3Dihub DanielRoquet Jack RFoucher PierreFroehlig FelixRenard JulienPottecher HortenseBesancenot FrancisSchneider MalekaSchenck StéphaneKremer inbook 5020 2015 6 17 115-129 Traduction des troubles suivants pour JF : Trouble psychotique induit par une substance ou un médicament Trouble psychotique dû à une autre affection médicale Catatonie associée à un autre trouble mental (spécification de type catatonique) Trouble catatonique dû à une autre affection médicale Catatonie non spécifiée Autre trouble du spectre de la schizophrénie ou autre trouble psychotique spécifié Trouble du spectre de la schizophrénie ou autre trouble psychotique non spécifié Traduction française coordonnée par J-D Guelfi et M-A Crocq Masson, Paris Section 2, Chapitre 2 DSM-V - Manuel diagnostique et statistique des troubles mentaux Traduction Français 978-2294739293 NicolasFrank Renaudde Beaurepaire YannHodé Jack RFoucher article 34 J Neuropsychiatry Clin Neurosci 2015 27 2 e168-9 www.ncbi.nlm.nih.gov/pubmed/25923872 _blank 10.1176/appi.neuropsych.14040079 LaurenceLalanne CamilleJantzi AGorse Marie-AgatheZimmermann Jean-MarieDanion Jack RFoucher article 35 PLoS One 2014 12 5 9 12 e114774 OBJECTIVES: We investigated the neural basis of hallucinations Alzheimer's disease (AD) by applying voxel-based morphometry (VBM) to anatomical and functional data from the AD Neuroimaging Initiative. METHODS: AD patients with hallucinations, based on the Neuropsychiatric Inventory (NPI-Q) (AD-hallu group; n = 39), were compared to AD patients without hallucinations matched for age, sex, educational level, handedness and MMSE (AD-c group; n = 39). Focal brain volume on MRI was analyzed and compared between the two groups according to the VBM method. We also performed voxel-level correlations between brain volume and hallucinations intensity. A similar paradigm was used for the PET analysis. "Core regions" (i.e. regions identified in both MRI and PET analyses, simply done by retaining the clusters obtained from the two analyses that are overlapping) were then determined. RESULTS: Regions with relative atrophy in association with hallucinations were: anterior part of the right insula, left superior frontal gyrus and lingual gyri. Regions with relative hypometabolism in association with hallucinations were a large right ventral and dorsolateral prefrontal area. "Core region" in association with hallucinations was the right anterior part of the insula. Correlations between intensity of hallucinations and brain volume were found in the right anterior insula, precentral gyrus, superior temporal gyrus, and left precuneus. Correlations between intensity of hallucinations and brain hypometabolism were found in the left midcingulate gyrus. We checked the neuropathological status and we found that the 4 patients autopsied in the AD-hallu group had the mixed pathology AD and Dementia with Lewy bodies (DLB). CONCLUSION: Neural basis of hallucinations in cognitive neurodegenerative diseases (AD or AD and DLB) include a right predominant anterior-posterior network, and the anterior insula as the core region. This study is coherent with the top-down/bottom-up hypotheses on hallucinations but also hypotheses of the key involvement of the anterior insula in hallucinations in cognitive neurodegenerative diseases. www.ncbi.nlm.nih.gov/pubmed/25479196 _blank 10.1371/journal.pone.0114774. eCollection 2014 FrédéricBlanc VincentNoblet NathaliePhilippi BenjaminCretin Jack RFoucher Jean-PaulArmspach FrançoisRousseau article 32 Clinical Genetic 2014 12 86 6 521-9 Bardet-Biedl syndrome (BBS) is a well-recognized ciliopathy characterized by cardinal features namely: early onset retinitis pigmentosa, polydactyly, obesity, hypogonadism, renal and cognitive impairment. Recently, disorders of olfaction (anosmia, hyposmia) have also been described in BBS patients. Moreover, morphological brain anomalies have been reported and prompt for further investigations to determine whether they are primary or secondary to peripheral organ involvement (i.e.: visual or olfactory neuronal tissue). The objective of this paper is to evaluate olfactory disorders in BBS patients and to investigate putative correlation with morphological cerebral anomalies. To this end, twenty BBS patients were recruited and evaluated for olfaction using the University of Pennsylvania Smell Identification Test (UPSIT). All of them underwent a structural MRI scan. We first investigated brain morphological differences between BBS subjects and 14 healthy volunteers. Then, we demonstrated objective olfaction disorders in BBS patients and highlight correlation between gray matter volume reduction and olfaction dysfunction in several brain areas. www.ncbi.nlm.nih.gov/pubmed/24684473 _blank accepted 10.1111/cge.12391 Jean-JacquesBraun VincentNoblet MyriamDurand SophieScheidecker AnnaZinetti Bertschy Jack RFoucher VincentMarion JeanMuller SophieRiehm HélèneDollfus StéphaneKremer article 28 Journal of Neuroscience Methods 2014 2 15 223 30-34 During the last years, many investigations have focused on spontaneously active cerebral networks such as the default-mode network (DMN). A data-driven technique, the independent component analysis (ICA), allows segregating such spontaneous (co-)activity maps (SAM) from noise in functional magnetic resonance imaging (fMRI) time series. To our knowledge, inter-rater reliability of manual selection, of not only DMN but all SAMs remained to be assessed. The current study was performed on 20 min (400 volumes) fMRI time series of 30 healthy participants. SAMs’ selection criteria were first established on past experience and from the literature. The inter-rater reliability of SAMs vs non-SAMs manual selection was then investigated from 250 independent components per participant. Results showed that inter-rater kappa coefficient was of 0.89 ± 0.01 on whole analysis, and 0.88 ± 0.09 on participant per participant analysis. The proposed SAM’s selection criteria are reliable enough to allow their scientific exploration at the single subject level. connect http://www.ncbi.nlm.nih.gov/pubmed/24316005 DanielRoquet Bich-ThuyPham Jack RFoucher book 503 2014 426#1891 Books on demand, Paris Traduction 978-2-3220-3850-3 Jack RFoucher FabriceBerna JulienElowe article 31 Epileptic Disord 2013 9 15 3 347-351 Psychosis is more common in people with temporal lobe epilepsy than it is in the general population. Treatment can be difficult in these patients because of the complex interactions between antipsychotic and antiepileptic drugs. Some antipsychotic drugs also decrease the seizure threshold. We report the case of a 49-year-old man with a hypothalamic hamartoma, with a history of both gelastic and temporal lobe seizures. The patient was rendered seizure-free after three neurosurgical procedures but developed a drug-resistant paranoid psychosis. He was treated with electroconvulsive therapy (ECT). After two weeks with six stimulations that resulted in seizures, the psychiatric phenomena disappeared completely. There was no relapse of either the psychiatric symptoms or the seizures during the 42 months of follow-up. This case report suggests that ECT might be safe for psychosis in patients with a history of seizures that have previously been successfully treated with neurosurgery, although caution should be exercised in drawing general conclusions from a single case report. http://www.ncbi.nlm.nih.gov/pubmed/23899761 ElisabethRuppert LaurenceLalanne Jack RFoucher Marie-AgatheZimmermann EdouardHirsch PierreVidailhet article 30 J Neuropsychiatry Clin Neurosci 2013 3 25 11-12 http://www.ncbi.nlm.nih.gov/pubmed/24026725 LaurenceLalanne JulienElowe Jean-MarieDanion PierreVidailhet Jack RFoucher article 29 Conf Proc IEEE Eng Med Biol Soc 2013 5352-5 In this paper, a custom robotic system for Transcranial Magnetic Stimulation is assessed in clinical conditions on healthy subjects. A motor cortex mapping is performed using the robotic system with comparison to a manual approach using a neuronavigation system. Stimulation accuracy, repeatability are evaluated as well as the feeling of the system operator and the subject in terms of comfort, tiredness, stress level, ease-of-use. Very encouraging results are obtained on all these aspects, which strengthens the idea of developing robotic assistance for TMS. validation http://www.axilumrobotics.com/pdf/A_Custom_Robot_for_Transcranial_Magnetic_Stimulation_First-EMBC2013.pdf http://www.ncbi.nlm.nih.gov/pubmed/24110945 RomualdGinhoux PierreRenaud LucileZorn LaurentGoffin BernardBayle Jack RFoucher JulienLamy Jean-PaulArmspach Michelde Mathelin article 27 PLoSOne 2012 7 4 e33878 Neuromyelitis optica (NMO) is an inflammatory disease of central nervous system characterized by optic neuritis and longitudinally extensive acute transverse myelitis. NMO patients have cognitive dysfunctions but other clinical symptoms of brain origin are rare. In the present study, we aimed to investigate cognitive functions and brain volume in NMO. The study population consisted of 28 patients with NMO and 28 healthy control subjects matched for age, sex and educational level. We applied a French translation of the Brief Repeatable Battery (BRB-N) to the NMO patients. Using SIENAx for global brain volume (Grey Matter, GM; White Matter, WM; and whole brain) and VBM for focal brain volume (GM and WM), NMO patients and controls were compared. Voxel-level correlations between diminished brain concentration and cognitive performance for each tests were performed. Focal and global brain volume of NMO patients with and without cognitive impairment were also compared. Fifteen NMO patients (54%) had cognitive impairment with memory, executive function, attention and speed of information processing deficits. Global and focal brain atrophy of WM but not Grey Matter (GM) was found in the NMO patients group. The focal WM atrophy included the optic chiasm, pons, cerebellum, the corpus callosum and parts of the frontal, temporal and parietal lobes, including superior longitudinal fascicle. Visual memory, verbal memory, speed of information processing, short-term memory and executive functions were correlated to focal WM volumes. The comparison of patients with, to patients without cognitive impairment showed a clear decrease of global and focal WM, including brainstem, corticospinal tracts, corpus callosum but also superior and inferior longitudinal fascicles. Cognitive impairment in NMO patients is correlated to the decreased of global and focal WM volume of the brain. Further studies are needed to better understand the precise origin of cognitive impairment in NMO patients, particularly in the WM. http://www.plosone.org/article/fetchObjectAttachment.action;jsessionid=5E4695493155B8FE217BCA915639F9A4?uri=info%3Adoi%2F10.1371%2Fjournal.pone.0033878&representation=PDF http://www.ncbi.nlm.nih.gov/pubmed/22509264 10.1371/journal.pone.0033878 FrédéricBlanc VincentNoblet BJung FrançoisRousseau FelixRenard BBourre NadineLongato NCremel LDi Bitonto CatherineKleitz NicolasCollongues Jack RFoucher StéphaneKremer Jean-PaulArmspach Jerômede Seze article 26 IEEE Trans Biomed Eng 2012 59 805-815 Transcranial magnetic stimulation is a noninvasive brain stimulation technique. It is based on current induction in the brain with a stimulation coil emitting a strong varying magnetic field. Its development is currently limited by the lack of accuracy and repeatability of manual coil positioning. A dedicated robotic system is proposed in this paper. Contrary to previous approaches in the field, a custom design is introduced to maximize the safety of the subject. Furthermore, the control of the force applied by the coil on the subject's head is implemented. The architecture is original and its experimental evaluation demonstrates its interest: the compensation of the head motion is combined with the force control to ensure accuracy and safety during the stimulation. validation http://www.ncbi.nlm.nih.gov/pubmed/22186930 LucileZorn PierreRenaud BernardBayle LaurentGoffin CyrilleLebossé Michelde Mathelin Jack RFoucher article 22 Schizophr Bull 2012 38 796-802 BACKGROUND: Aged patients (>50 years old) with residual schizophrenic symptoms differ from young patients. They represent a subpopulation with a more unfavorable Kraepelinian course and have an increased risk (up to 30%) for dementia of unknown origin. However, our current understanding of age-related brain changes in schizophrenia is derived from studies that included less than 17% of patients who were older than 50 years of age. This study investigated the anatomical distribution of gray matter (GM) brain deficits in aged patients with ongoing schizophrenia. METHODS: Voxel-based morphometry was applied to 3D-T1 magnetic resonance images obtained from 27 aged patients with schizophrenia (mean age of 60 years) and 40 age-matched normal controls. RESULTS: Older patients with schizophrenia showed a bilateral reduction of GM volume in the thalamus, the prefrontal cortex, and in a large posterior region centered on the occipito-temporo-parietal junction. Only the latter region showed accelerated GM volume loss with increasing age. None of these results could be accounted for by institutionalization, antipsychotic medication, or cognitive scores. CONCLUSIONS: This study replicated most common findings in patients with schizophrenia with regard to thalamic and frontal GM deficits. However, it uncovered an unexpected large region of GM atrophy in the posterior tertiary cortices. The latter observation may be specific to this aged and chronically symptomatic subpopulation, as atrophy in this region is rarely reported in younger patients and is accelerated with age. http://www.ncbi.nlm.nih.gov/pubmed/21205677 CarolineSchuster Anne-MarieSchuller CarlosPaulos Izzie JNamer CharlesPull Jean-MarieDanion Jack RFoucher inbook 403 2012 Jardri R, Cachia A, Thomas P, Pins D http://www.springer.com/medicine/psychiatry/book/978-1-4614-4120-5 Jardri, Renaud Springer-Verlag

New York

The Neuroscience of Hallucinations 978-1461441205 Jack RFoucher article 24 J Magn Reson Imaging 2011 34 785-790 PURPOSE: To take into account the echo time (TE) influence on arterial spin labeling (ASL) signal when converting it in regional cerebral blood flow (rCBF). Gray matter ASL signal decrease with increasing TE as a consequence of the difference in the apparent transverse relaxation rates between labeled water in capillaries and nonlabeled water in the tissue (?R?2*). We aimed to measure ASL/rCBF changes in different parts of the brain and correct them. MATERIALS AND METHODS: Fifteen participants underwent ASL measurements at TEs of 9.7-30 ms. Decreases in ASL values were localized by statistical parametric mapping. The corrections assessed were a subject-per-subject adjustment, an average ?R?2* value adjustment, and a two-compartment model adjustment. RESULTS: rCBF decreases associated with increasing TEs were found for gray matter and were corrected using an average ?R?2* value of 20 s(-1) . Conversely, for white matter, rCBF values increased with increasing TEs (?R?2* = -23 s(-1)). CONCLUSION: Our correction was as good as using a two-compartment model. However, it must be done separately for the gray and white matter rCBF values because the capillary R?2* values are, respectively, larger and smaller than those of surrounding tissues. http://www.ncbi.nlm.nih.gov/pubmed/21769973 Jack RFoucher DanielRoquet CorinneMarrer Bich-ThuyPham DanielGounot article 23 Brain Res 2011 1400 66-77 Most classical neuroimaging studies of human memory require the subject to follow task instructions, discriminate stimuli, make a decision and, finally, press a button to respond. To which extent does such a cognitive sequence influence neural correlates of recognition memory especially with respect to the prefrontal cortex (PFC) is not clear yet. We set up a naturalistic recognition task. Personal photographs were mixed with photographs from family albums of people who were not known to the participant. The subjects alternated a recognition task (recognition and response) with a mere observational one (simple recognition). This factorial block-event functional MRI design allowed us to disentangle the regions related to memory (personal photographs vs. distracters under both conditions) from those related to the response (responding vs. observing) as well as to examine the interaction between the two factors. Only medial and left orbito-frontal regions were transiently active during successful recognition in the two task conditions. Memory and responding interacted in the left lateral PFC within the middle and inferior gyrus. These regions were more active for personal photographs than for distracters only when the subject had to respond. Sustained activations spread bilaterally whatever the task. Such a design that encompasses personal photographs, an observation period for recognition as well as a mixed-design may have led to a better isolation of the neural network underlying remote autobiographical memory. Recruitment within the PFC during retrieval was only limited to its medial and left anterior parts. Sustained activation did not differ between the discrimination and the observation period. This original design might be valuable for further dissociation between decision, self, autobiographical memory and the PFC. http://www.ncbi.nlm.nih.gov/pubmed/21640981 JulienDetour Jean-MarieDanion DanielGounot CorinneMarrer Jack RFoucher inbook 402 2011 64-74 “Angst-Glücks-Psychose” has several translations in the literature: anxiety-happiness psychosis (AHP), anxiety-elation or anxiety-bliss psychosis. AHP is one of the 3 phenotypes of the cycloid psychosis (CP) as defined by the Wernicke-Kleist-Leonhard (WKL) school [26]. CP are bipolar psychoses in that they manifest in two opposite clinical pictures that may alternate from one episode to the next or during the same episode (mixed state). AHP as all CP has a purely relapsing-remitting course without accumulation of other symptoms between episodes; this can be opposed to nonsystematic schizophrenias that come with an initial episodic course as well, but where residual symptoms, e.g. lameness, indifference of affect up to flatness or blunting, loss of drive, but also other symptoms such as paranoia, hallucination, language disorders, increase at each remission. Psychosis or emotional disturbance could either appear as prevalent to a ICD/DSM formatted mind, but this symptomatology is too rough to distinguish them from non-systematic schizophrenias. WKL http://paperc.de/16055-das-glueck-9783898386470#!/pages/I fileadmin/Restreint/Anxiety-happiness_psychosis.pdf Johannes Schröder und Frank G. Brecht Akademische Verlagsgesellschaft GmbH

Heidelberg

IX. Symposium zur interdisziplinären Arbeit in der Sozialpsychiatrie Das Glück: Eine interdisziplinäre und klinische Betrachtung Jack RFoucher ValérieBennouna-Greene FabriceBerna BrunoPfuhlman GeraldStöber article 304 Ann Med Psychol (Paris) 2010 8 609–615 Les classifications internationales en psychiatrie, la CIM et le DSM, ont permis un accroissement rapide des connaissances factuelles sur les troubles qu’elles définissent, sans que cela se soit accompagné d’un accroissement de leur validité. La notion de validité n’est applicable qu’aux classifications scientifiques. Celles-ci cherchent à modéliser la réalité de phénomènes naturels. Ce qui est validable dans une classification scientifique, c’est ce modèle. En médecine, une maladie correspond à un modèle étio-physiopathologique de la déviation morbide d’un processus naturel. Or, la CIM et le DSM étant athéoriques, ils ne reposent sur aucun modèle et sont donc invalidables. Ainsi, l’utilité de ces classifications doit être limitée à la pratique technique. À vouloir les appliquer en science, ces instruments ne peuvent que ralentir toute avancée basée sur la méthode classique des corrélations cliniques. WKL http://www.sciencedirect.com/science/article/pii/S0003448710002532 fileadmin/Restreint/CIM_DSM_L_impossible_validation.pdf Français Jack RFoucher ValérieBennouna-Greene article 21 J Clin Psychiatry 2010 72 1157 http://www.ncbi.nlm.nih.gov/pubmed/20409450 MehdiBennouna-Greene JFrank StéphaneKremer ClaudeBursztejn Jack RFoucher article 19 Brain Cogn 2010 72 255-263 Working memory is devoted to the temporary storage and on-line manipulation of information. Recently, an integrative system termed the episodic buffer has been proposed to integrate and hold information being entered or retrieved from episodic memory. Although the brain system supporting such an integrative buffer is still in debate, the medial temporal lobe appears to be a promising candidate for the maintenance of bound information. In the current work, binding was assessed by comparing two conditions in which participants had to retain three letters and three spatial locations presented either bound or separate. At the behavioral level, lower performance was found for bound information than for separate information. When contrasting the two conditions, activation in the right parahippocampal gyrus was greater for the encoding and maintenance of bound information. No activation was observed in the medial temporal lobe during the retrieval of bound information. Together, our results suggest that the parahippocampal gyrus may underlie the integrative and maintenance functions of the episodic buffer. http://www.ncbi.nlm.nih.gov/pubmed/19837500 DavidLuck Jean-MarieDanion CorinneMarrer Bich-ThuyPham DanielGounot Jack RFoucher article 20 Hippocampus 2010 20 936-948 Alterations of binding in long-term memory in schizophrenia are well established and occur as a result of aberrant activity in the medial temporal lobe (MTL). In working memory (WM), such a deficit is less clear and the pathophysiological bases remain unstudied. Seventeen patients with schizophrenia and 17 matched healthy controls performed a WM binding task while undergoing functional magnetic resonance imaging. Binding was assessed by contrasting two conditions comprising an equal amount of verbal and spatial information (i.e., three letters and three spatial locations), but differing in the absence or presence of a link between them. In healthy controls, MTL activation was observed for encoding and maintenance of bound information but not for its retrieval. Between-group comparisons revealed that patients with schizophrenia showed MTL hypoactivation during the maintenance phase only. In addition, BOLD signals correlated with behavioral performance in controls but not in patients with schizophrenia. Our results confirm the major role that the MTL plays in the pathophysiology of schizophrenia. Short-term and long-term relational memory deficits in schizophrenia may share common cognitive and functional pathological bases. Our results provide additional information about the episodic buffer that represents an integrative interface between WM and long-term memory. http://www.ncbi.nlm.nih.gov/pubmed/19693783 DavidLuck Jean-MarieDanion CorinneMarrer Bich-ThuyPham DanielGounot Jack RFoucher article 18 Conf Proc IEEE Eng Med Biol Soc 2009 2009 3497-3500 Most brain functional connectivity methods in fMRI require a brain parcellation into functionally homogeneous regions. In this work we propose a novel parcellation approach based on a spatial hierarchical clustering, that provides clusters within a multi-level framework. The method has the advantage of producing several brain parcellations rather than a single one from a fixed size-homogeneity criterion. Results obtained on real data demonstrate the relevance of the approach. Finally, a connectivity study shows the benefit of a prior multi-level parcellation of the brain. http://www.ncbi.nlm.nih.gov/pubmed/19964995 SlimKarkar SylvainFaisan LaurentThoraval Jack RFoucher book 501 2009 288 Cet ouvrage ne concerne pas l'histoire des psychoses, mais bien l'avenir de la psychiatrie médicale concernant ces pathologies qui touchent un peu plus de 3% de la population. Pour les esprits curieux de cerner et distinguer ces psychoses, le DSM comme la CIM s'avèrent particulièrement décevants. Aucune de ces classifications ne cherche à définir des entités morbides naturelles, c.-à-d. des maladies. Il ne s'agit que de regroupements symptomatiques obtenus par consensus d'un collège d'experts. En l'absence d'une classification étiologique ou physiopathologique, cette approche est un pis aller acceptable, puisqu'il permet d'adopter un langage commun et donc l'accumulation d'une base de connaissance empirique. Paradoxalement bien qu'une insatisfaction soit perceptible, tout le monde semble se satisfaire de ces définitions, et la recherche d'une classification naturelle est curieusement devenue marginale, générant au mieux indifférence ou incrédulité. Et pourtant ... Dans la nuit du 12 au 13 août 1961, le mur "de la honte" isole Karl Leonhard, le maître de l'Hôpital de la Charité de Berlin Est, privant l'Ouest de sa classification des psychoses, la plus proche d'une classification naturelle. Heureusement, tout n'est pas perdu. Angst à Zurich et Perris à Umea, grands adeptes de Leonhard, répliquent les résultats obtenus sur les troubles bipolaires et unipolaires de l'humeur et savent convaincre les pays de l'Ouest de la pertinence d'une telle séparation. Mais l'œuvre ne se limite pas à cela ! Leonhard n'isole pas moins de 35 formes différentes, classées en 5 familles dont le pronostic reste très distinct : les psychoses maniaco-dépressives, les dépressions et les manies unipolaires, les psychoses cycloïdes, les schizophrénies non-systématisées et les schizophrénies systématisées. Il montre en plus que leur charge héréditaire varie de 1 à 15. Ses successeurs confirment et étendent ces premières observations. Actuellement la somme des cohortes dépasse allègrement les 6000 patients, avec pour certaines études un suivi prospectif de plus de 30 ans, permettant d'assurer la robustesse du diagnostic sur la vie entière du patient et non pas sur un épisode pathologique comme le permettent les classifications actuelles. Il est curieux que les chercheurs ne se soient pas emparés de cet instrument. C'est tout particulièrement vrai pour la recherche en génétique. En effet, certaines formes, comme la catatonie périodique sont particulièrement chargées sur le plan héréditaire, alors que d'autres, telles les schizophrénies systématisées ne le sont pas du tout. Ces dernières sont en revanche chargées en événements ontogéniques. Appliqués à la clinique, les tableaux définis par Leonhard sont la plupart du temps d'une remarquable pertinence, et le plus souvent aisés à reconnaître. Ils ont l'avantage d'établir un pronostic plus fiable, et d'ouvrir sur des prises en charge thérapeutiques plus adaptées. Ainsi, les psychoses cycloïdes que nous reconnaissons souvent comme des schizophrénies dans les classifications actuelles, ont un excellent pronostic et ne relèveraient pas systématiquement d'un traitement neuroleptique au long cours. Inversement certaines schizophrénies non-systématisées débutent par une bouffée délirante et mériteraient d'être traitées non pas quelques mois ou années au delà de l'épisode, mais à vie pour éviter une évolution défavorable. Enfin, la plupart des schizophrénies systématisées, de mauvais pronostic sont souvent résistantes aux thérapeutiques actuelles. Ce livre est une introduction destinée à faire connaître aux psychiatres français les bases de ce joyau de la psychopathologie clinique ainsi que les différentes découvertes fondamentales et pratiques qui en découlent. Puissent les esprits curieux être interpellés et se saisir de cet instrument remarquable tant dans la pratique clinique que dans la recherche. 426#1890 http://books.google.fr/books?id=xy_DuXtq7ooC&printsec=frontcover&hl=fr&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false http://www.bod.fr/index.php?id=1786&objk_id=245541 Books on demand

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Français 978-2-8106-1552-0 Jack RFoucher inbook 502 2009 21-28 Journées Pierre Denicker 8ème journée Pierre Denicker French Jack RFoucher inbook 401 2009 http://superieur.deboeck.com/titres/127914_2_0/stimulation-magnetique-transcranienne-principes-et-applications-en-psychiatrie.html Brunelin J, Galinowski A, Januel D et Poulet E Solal Stimulation Magnétique Transcrânienne : Principes et applications en psychiatrie Français 978-2353270699 Jack RFoucher article 15 Schizophrenia Res 2008 97 118-127 The guarantee of perceptual coherence for events through everyday life situations depends upon the capacity to correctly integrate series of multi-sensory experiences. Patients with schizophrenia have been shown to reveal a deficit in integrating, i.e., "binding", perceptual information together. However, results in the literature have also suggested the reverse effect. Indeed, in certain paradigms patients have revealed more binding phenomenon than healthy controls and reported experiencing two distinct events as occurring "together". This finding suggests that patients may require longer time intervals between two distinct events before being able to perceive them as "one-after-the-other". The question here was to test whether this perceptual binding abnormality in schizophrenia is confined to events within the same modality or whether it is also present across sensory modalities. Thirty patients with schizophrenia were compared with 33 normal controls using a simultaneity judgement paradigm. There were two uni-modal conditions in which stimuli were presented in the same modality (visual or auditory) and one bimodal condition (audio-visual). Participants were presented with stimuli varying across a range of inter-stimulus intervals (ISI). They were required to judge whether they experienced two stimuli as occurring "together" or "one-after-the-other". Compared to controls and in all conditions, patients needed larger ISI to experience two stimuli as "one-after-the-other" (all ISI x Group interactions p<5 x 10(-5)). These abnormalities correlated with the disorganization dimension but not with the dosage of chlorpromazine equivalent. The increase of the time interval needed to perceive two stimuli as "one-after-the-other", reflect an abnormally low time resolution in patients with schizophrenia. We discuss the possible involvement of anatomical disconnectivity in schizophrenia which would specifically affect the time integration properties of neural assemblies. http://www.ncbi.nlm.nih.gov/pubmed/17884350 Jack RFoucher MathieuLacambre Bich-ThuyPham AnneGiersch Marc AElliott article 16 Schizophrenia Res 2008 100 153-160 If disturbance of binding in long term memory is well established in schizophrenia, data concerning working memory maintenance are less clear. Feature binding in working memory was investigated in 19 patients with schizophrenia and 19 healthy controls. Binding was assessed by comparing two conditions in which participants had to retain four letters and four spatial locations. These features were presented either bound or separate. Results showed that both groups had better performances for bound than separate features, despite the fact that patients performed significantly worse than controls. When maintenance for isolated features was assessed, patients were severely disturbed for spatial locations but not for letters. Such a result suggests that reduced working memory performance in patients with schizophrenia for bound features is probably a consequence of a spatial deficit rather than a specific deficit of the binding process. Thus, not all form of binding are disturbed in schizophrenia. http://www.ncbi.nlm.nih.gov/pubmed/18093803 DavidLuck Jack RFoucher IsabelleOfferlin-Meyer MartinLepage Jean-MarieDanion article 303 Encephale 2007 33 982-989 Repetitive trans-cranial magnetic stimulation (rTMS) can modulate cortical excitability. Consequently, it appears appealing for the treatment of some affections such as depression or hallucinations. There is already some proof that the concept is valid, but rTMS is slow in progressing in the therapeutic field as a true armamentum. Indeed its effects are of short duration and even inconstant from one patient to the next. These drawbacks depend on certain factors that we will discuss. Until now, there has been inadequate control of the stimulation site. It is possible that this site could vary on an individual basis. It seems logical to propose the use of functional imaging for such a purpose, but its use should be adapted to the symptom. Even after localizing the site, the coil has to be placed accurately. This could be facilitated by a neuronavigator. Stimulation protocols are currently defined by three parameters: the frequency modulating the cortical action either as a stimulation (>5 Hz) or an inhibition (<1 Hz), the intensity and the number of stimuli influencing, notably, the amplitude and duration of the effect. Unfortunately, the effect is inconstant in a given patient and paradoxical reactions have been observed in more than 15% of normal individuals. Improved reliability and amplification of the effect rely on the better control of other parameters: pattern of stimulation, pre and post-conditioning, state of the cortex during stimulation, associated medications, endogenous idiosyncratic factors and related pathology. We will review the current physiological literature to discuss the possible options that would constitute a rational basis for setting up more efficient protocols. http://www.cercle-d-excellence-psy.org/fileadmin/cep_files/TMS_TTT_CEP.pdf http://www.cercle-d-excellence-psy.org/fileadmin/cep_files/TMS_TTT_CEP.pdf Français Jack RFoucher DavidLuck SergeChassagnon IsabelleOfferlin-Meyer Bich-ThuyPham article 12 Asian Hospital & Healthcare Management 2007 http://www.asianhhm.com/Knowledge_bank/articles/transcranial_magnetic_stimulation.htm http://www.asianhhm.com/Knowledge_bank/articles/transcranial_magnetic_stimulation.htm Jack RFoucher CyrilleLebossé PierreRenaud BernardBayle Michelde Mathelin article 14 Neurosci Res 2007 57 230-239 In functional cerebral studies, it has been established that co-registered electroencephalography (EEG) measurements and functional magnetic resonance imaging (fMRI) were complementary. However, EEG data recorded inside an MRI scanner are heavily distorted, mainly by the most prominent artifact, the cardiac pulse artifact (PA). We describe an original algorithm which yields a high-quality PA filter and demonstrates how this tool can be used to improve the quality of P300 ERP measurements during event-related fMRI (e-fMRI) experiments. EEG data were acquired in interleaved mode during e-fMRI while six healthy volunteers performed a visual odd-ball task, involving Distractors, Target and Novel stimuli, to elicit P300 components. The PA was corrected with the original algorithm. The temporal variations in the PA were evidenced using a principal component analysis (PCA), on each EEG channel. The procedure yielded several PA templates, which were regressed from the EEG data. The PA removal procedure was optimised, and then implemented to improve the measured P300 components. Regressing the most adequate PA template resulted in a high-quality reduction in spectral power at frequencies associated with the cardiac PA. More reliable P300 component measurements were obtained, evidencing higher amplitudes for Novels (9.76-11.20 microV) than for to Targets (6.3-9.09 microV) in centro-parietal and prefrontal areas. The improvement of the processing of EEG data acquired simultaneously with fMRI data provides a new tool and casts perspectives to study the functional organisation of the brain. http://www.ncbi.nlm.nih.gov/pubmed/17157401 HélèneOtzenberger DanielGounot Jack RFoucher article 13 Image and Vision Computing 2007 25 512-521 Magnetic resonance angiography (MRA) provides three-dimensional data of vascular structures by visualising the flowing blood signal. Algorithms dedicated to vessel segmentation generally detect the cerebral vascular tree by only seeking this high intensity blood signal in MRA data. The method presented in this paper proposes a different strategy which consists in using both MRA and classical MRI in order to integrate a priori anatomical knowledge for guidance of the vessel segmentation process. It then uses mathematical morphology tools to carry out a simultaneous segmentation of both blood signal in MRA and blood and wall signal in MRI, enabling to take advantage of a larger amount of information than previously proposed methods. This method is dedicated to the superior sagittal sinus segmentation; however, similar strategies could be considered for segmentation of other vascular structures. It has been performed on a database composed of 9 couples of MRA and MRI, providing results which have been validated and compared to other ones obtained with a region-growing algorithm. Their validation tends to prove that the proposed method is reliable even when the vascular signal is inhomogeneous or contains artifacts. http://www.sciencedirect.com/science/journal/02628856/25/4 NicolasPassat ChristianRonse JosephBaruthio Jean-PaulArmspach Jack RFoucher article 11 Dialogues Clin Neurosci 2006 8 17-27 Schizophrenia is still a condition with obscure causes and psychopathology. This paper aims to discuss the "disconnectivity" hypothesis in relation to some neurological conditions which are known to alter brain connectivity, as well as mimicking some aspects of the disorder. After a short historical introduction to the concept, we will examine the evidence for connectivity problems in schizophrenia, separating the anatomical level from the functional level. Then, we will discuss three different issues concerning connectivity: i) local reduction in connectivity without neuronal loss (within the gray matter); ii) reduction in or alteration of long-range connectivity (within the white matter); and iii) abnormal targets for connections. For each of these aspects, we will look at the conditions able to reproduce anomalies capable of increasing susceptibility to schizophrenia. We conclude that psychosis is more likely to occur: i) when long-range connectivity is concerned; ii) when lesions result in lengthening and scattering of conduction times; and iii) when there are high dopamine levels, shedding light on or adding weight to the idea of an interaction between dopamine and connectivity. http://www.dialogues-cns.com/publication/psychosis-related-to-neurological-conditions-pro-and-cons-of-the-dis-mis-connectivity-models-of-schizophrenia/ http://www.ncbi.nlm.nih.gov/pubmed/16640110 Jack RFoucher DavidLuck article 302 Epileptologie 2005 22 157-167 Les effets thérapeutiques de la Stimulation Magnétique Transcrânienne répétitive (SMTr) sont aujourd’hui explorés dans plusieurs pathologies psychiatriques et neurologiques lors desquelles cette technique semble capable de modifier le fonctionnement de structures ou de réseaux corticaux dysfonctionnels. Bien que son efficacité thérapeutique soit maintenant attestée par un nombre croissant de travaux dans certaines de ces pathologies, la SMTr est encore peu utilisée dans la pratique clinique et reste surtout étudiée dans le cadre de protocoles de recherche. Cela tient pour une part à la courte durée de ses effets et au caractère inconstant de ceux-ci d’un sujet à l’autre, dans ses modalités d’administration actuelles. Après un rappel du principe général de fonctionnement de la SMTr nous essayerons, au travers de la revue de la littérature concernant son application dans l’épilepsie et les hallucinations, de dégager certains facteurs susceptibles d’influencer l’effet obtenu. Nous envisagerons successivement : le choix du site de stimulation et sa localisation, les paramètres de stimulation (le nombre de stimuli délivrés, l’intensité et la fréquence de stimulation, son degré de focalisation), les médicaments associés, le patron de stimulation, et la question du conditionnement cortical pré-, per- et post-stimulation. Pour ces différents facteurs, nous proposerons des pistes de recherche qui pourraient permettre d’obtenir, dans le futur, une amélioration de l’efficacité de la SMTr et de faire accéder cette technique au rang de méthode thérapeutique à part entière. http://www.epi.ch/_files/Artikel_Epileptologie/Vidailhet_4_05.pdf http://www.epi.ch/_files/Artikel_Epileptologie/Vidailhet_4_05.pdf Français PierreVidailhet Jack RFoucher ValérieLauer SergeChassagnon article 8 Accad Radiol 2005 12 25-36 RATIONALE AND OBJECTIVES: Most methods used in functional MRI (fMRI) brain mapping require restrictive assumptions about the shape and timing of the fMRI signal in activated voxels. Consequently, fMRI data may be partially and misleadingly characterized, leading to suboptimal or invalid inference. To limit these assumptions and to capture the broad range of possible activation patterns, a novel statistical fMRI brain mapping method is proposed. It relies on hidden semi-Markov event sequence models (HSMESMs), a special class of hidden Markov models (HMMs) dedicated to the modeling and analysis of event-based random processes. MATERIALS AND METHODS: Activation detection is formulated in terms of time coupling between (1) the observed sequence of hemodynamic response onset (HRO) events detected in the voxel's fMRI signal and (2) the "hidden" sequence of task-induced neural activation onset (NAO) events underlying the HROs. Both event sequences are modeled within a single HSMESM. The resulting brain activation model is trained to automatically detect neural activity embedded in the input fMRI data set under analysis. The data sets considered in this article are threefold: synthetic epoch-related, real epoch-related (auditory lexical processing task), and real event-related (oddball detection task) fMRI data sets. RESULTS: Synthetic data: Activation detection results demonstrate the superiority of the HSMESM mapping method with respect to a standard implementation of the statistical parametric mapping (SPM) approach. They are also very close, sometimes equivalent, to those obtained with an "ideal" implementation of SPM in which the activation patterns synthesized are reused for analysis. The HSMESM method appears clearly insensitive to timing variations of the hemodynamic response and exhibits low sensitivity to fluctuations of its shape (unsustained activation during task). Real epoch-related data: HSMESM activation detection results compete with those obtained with SPM, without requiring any prior definition of the expected activation patterns thanks to the unsupervised character of the HSMESM mapping approach. Along with activation maps, the method offers a wide range of additional fMRI analysis functionalities, including activation lag mapping, activation mode visualization, and hemodynamic response function analysis. Real event-related data: Activation detection results confirm and validate the overall strategy that consists in focusing the analysis on the transients, time-localized events that are the HROs. CONCLUSION: All the experiments performed on synthetic and real fMRI data demonstrate the relevance of HSMESMs in fMRI brain mapping. In particular, the statistical character of these models, along with their learning and generalizing abilities are of particular interest when dealing with strong variabilities of the active fMRI signal across time, space, experiments, and subjects. http://www.ncbi.nlm.nih.gov/pubmed/15691723 SylvainFaisan LaurentThoraval Jean-PaulArmspach Jack RFoucher Marie-NoëlMetz-Lutz FabriceHeitz article 9 Cog Brain Res 2005 23 306-315 Analysis of combined event-related potentials (ERP) and functional magnetic resonance imaging (fMRI) can provide a high temporal and high spatial resolution to study functional cerebral processes. However, EEG data recorded inside an MR scanner is heavily distorted by artifacts. It is important in cognitive studies to ensure that recorded data reflect the same brain activity, and this is achieved through interleaved electroencephalographic (EEG) and fMRI measurements. Here, we demonstrate the feasibility of recording P300 ERPs during fMRI using a three-stimulus visual oddball task and involving a small number of trials for each stimulus. Ten EEG channels were acquired interleaved with fMRI images in five healthy subjects. The stimuli, including rare targets "X," frequent repetitive distractors "O," and rare distractors referred to as novels, were randomly presented every 2 +/- 1 s. The post hoc filter presented here was designed and applied to EEG data to remove the cardiac pulse artifact. Interleaved EEG/fMRI acquisition evidenced two P300 ERPs evoked at Fz, Cz, and Pz by targets and novels. Novel-related ERPs were of higher amplitude than their target-related counterparts. The fMRI maps acquired concurrently showed stronger BOLD response for target condition. We have shown that interleaved acquisition allows to obtain reliable P300 data and fMRI results, likely to shed light on the anatomical location of brain regions involved in cognitive ERPs relevant to many disorders affecting CNS functions. These noninvasive multimodal neuroimaging techniques can be used to explore and better understand processes underlying the functional brain organization. http://www.ncbi.nlm.nih.gov/pubmed/15820638 HélèneOtzenberger DanielGounot Jack RFoucher article 10 NeuroImage 2005 26 374-388 The disconnectivity hypothesis proposes that schizophrenia results from poor or miswired anatomical connections. Theoretically, its functional counterpart should be disintegration. Integration is thought to allow segregated neurons to interact as a coherent whole, referred to as the "core", while the non-interacting part of the brain is referred to as the "rest". In this study, it is suggested that schizophrenia is the result of rest noise interfering with core activity. Two possible causes are assessed: (i) defective core integration, making the core more vulnerable to noise from the rest, or (ii) the rest being too highly integrated, meaning that it can interfere with the core. These hypotheses were tested using fMRI data acquired from 13 stabilized medicated schizophrenic subjects compared to 11 matched controls. Subjects were required to perform a series of lexical decision and retrieval tasks in separate sessions. The brain was divided into 90 components. Integration was defined as the amount of information shared between the components of a sub-system. An iterative aggregation procedure made it possible to identify a core on the basis of the functional clustering index, which assesses the integration of the core relative to its integration with the rest. Correlation of component-pairs within the core was also compared between the two groups. This procedure was repeated for each subject and for each task. Cores did not differ between the two groups, either in terms of integration or in terms of functional clustering index. However, the core was still highly integrated with the rest and the rest was overly integrated in schizophrenic subjects. Both anomalies were correlated with the negative symptoms. These findings were consistent regardless of the task considered. Furthermore, within the core, anterior-posterior correlations were lower in patients (between the frontal and the parietal and posterior cingulate cortices), whereas frontal left-right correlations were excessive. No significant correlation was found with the medication. Thus, it appears that schizophrenia entails a deleterious combination of too much "noisy" integration (from the rest) and too little "significant" integration (anterior-posterior functional connectivity). http://www.ncbi.nlm.nih.gov/pubmed/15907297 Jack RFoucher PierreVidailhet SandraChanraud DelphinePins DanielGounot Jean-MarieDanion article 6 NeuroImage 2004 22 688-697 In this fMRI study, we looked for the regions supporting interaction between cortical arousal and attention during three conditions: detection, observation, and rest. Arousal measurements were obtained from the EEG low-frequency (LF) power (5-9.5 Hz) recorded continuously together with fMRI. Whatever the condition, arousal was positively correlated with the fMRI signal of the right dorsal-lateral prefrontal and superior parietal cortices, closely overlapping regions involved in the maintenance of attention. Although the inferior temporal areas also presented a correlation with arousal during detection, path analysis suggests that this influence may be indirect, through the top-down influence of the previously mentioned network. However, those visual-processing areas could account for the correlation between arousal and performances. Lastly, the medial frontal cortex, frontal opercula, and thalamus were inversely correlated with arousal but only during detection and observation so that they could account for the control of arousal. http://www.ncbi.nlm.nih.gov/pubmed/15193597 Jack RFoucher HélèneOtzenberger DanielGounot article 7 Neuropsychologia 2004 42 1247-1259 The present study sought to assess neural correlates of implicit identification of objects by means of fMRI, using tasks that require matching of the physical properties of objects. Behavioural data suggests that there is automatic access to object identity when observers attend to a physical property of the form of an object (e.g. the object's orientation) and no evidence for semantic processing when subjects attend to colour. We evaluated whether, in addition to neural areas associated with decisions to specific perceptual properties, areas associated with access to semantic information were activated when tasks demanded processing of the global configuration of pictures. We used two perceptual matching tasks based on the global orientation or on the colour of line drawings. Our results confirmed behavioural data. Activations in the inferior occipital cortex, fusiform and inferior temporal gyri in both tasks (orientation and colour) account for perceptual and structural processing involved in each task. In contrast, activations in the posterior and medial parts of the fusiform gyrus, shown to be involved in explicit semantic judgements, were more pronounced in the orientation-matching task, suggesting that semantic information from the pictures is processed in an implicit way even when not required by the task. Thus, this study suggests that cortical regions usually involved in explicit semantic processing are also activated when implicit processing of objects occurs. http://www.ncbi.nlm.nih.gov/pubmed/15178176 DelphinePins Marc-EtienneMeyer Jack RFoucher Glyn WHumphreys MurielBoucart article 5 BMC Neurosci 2003 4 22 BACKGROUND: The integration of EEG and fMRI is attractive because of their complementary precision regarding time and space. But the relationship between the indirect hemodynamic fMRI signal and the more direct EEG signal is uncertain. Event-related EEG responses can be analyzed in two different ways, reflecting two different kinds of brain activity: evoked, i.e. phase-locked to the stimulus, such as evoked potentials, or induced, i.e. non phase-locked to the stimulus such as event-related oscillations. In order to determine which kind of EEG activity was more closely related with fMRI, EEG and fMRI signals were acquired together, while subjects were presented with two kinds of rare events intermingled with frequent distractors. Target events had to be signaled by pressing a button and Novel events had to be ignored. RESULTS: Both Targets and Novels triggered a P300, of larger amplitude in the Novel condition. On the opposite, the fMRI BOLD response was stronger in the Target condition. EEG event-related oscillations in the gamma band (32-38 Hz) reacted in a way similar to the BOLD response. CONCLUSIONS: The reasons for such opposite differential reactivity between oscillations / fMRI on the one hand, and evoked potentials on the other, are discussed in the paper. Those results provide further arguments for a closer relationship between fast oscillations and the BOLD signal, than between evoked potentials and the BOLD signal. http://www.biomedcentral.com/content/pdf/1471-2202-4-22.pdf http://www.ncbi.nlm.nih.gov/pubmed/14499000 Jack RFoucher HélèneOtzenberger DanielGounot article 3 J Neurosci Methods 2001 111 83-98 The quantification of phase synchrony between neuronal signals is of crucial importance for the study of large-scale interactions in the brain. Two methods have been used to date in neuroscience, based on two distinct approaches which permit a direct estimation of the instantaneous phase of a signal [Phys. Rev. Lett. 81 (1998) 3291; Human Brain Mapping 8 (1999) 194]. The phase is either estimated by using the analytic concept of Hilbert transform or, alternatively, by convolution with a complex wavelet. In both methods the stability of the instantaneous phase over a window of time requires quantification by means of various statistical dependence parameters (standard deviation, Shannon entropy or mutual information). The purpose of this paper is to conduct a direct comparison between these two methods on three signal sets: (1) neural models; (2) intracranial signals from epileptic patients; and (3) scalp EEG recordings. Levels of synchrony that can be considered as reliable are estimated by using the technique of surrogate data. Our results demonstrate that the differences between the methods are minor, and we conclude that they are fundamentally equivalent for the study of neuroelectrical signals. This offers a common language and framework that can be used for future research in the area of synchronization. http://www.ncbi.nlm.nih.gov/pubmed/11595276 MichelLe van Quyen Jack RFoucher Jean-PhilippeLachaux EugenioRodriguez AntoineLutz JacquesMartinerie Francisco JVarela article 4 Epileptic Disord 2001 Special Issue 91-98 It could seem strange that a same neuro-physiological mechanism provides for both normal and critical cerebral activity. While describing the basics of "cognitive" synchronies we will contrast them with the "critical" one for their differentiation and their non-rhythmic properties. Lastly we will speculate on their significance in the recently described seizure anticipation paradigm and on the possibility that they could share common generators. http://www.ncbi.nlm.nih.gov/pubmed/11781204 Jack RFoucher article 2 Neuroreport 2000 11 2379-2383 Boucart and Humphreys reported an automatic access to object identity when observers attend to a physical property of the form of an object (e.g. the orientation) but not to its colour. We sought evidence for automatic identification in a brain imaging study using fMRI. In an orientation decision task participants decided whether a picture was vertical or horizontal. In the colour decision task participants decided if a picture was blue or green. Activation of areas 18-19 was found for both color and orientation. Activation of the temporal area 37 occurred more frequently in the orientation than in the colour decision task. This result suggests that automatic identification activates the same brain area as overt processing of semantic information. http://www.ncbi.nlm.nih.gov/pubmed/10943689 MurielBoucart Marc-EtienneMeyer DelphinePins Glyn WHumphreys ChristianScheiber DanielGounot Jack RFoucher article 301 Revue de Médecine Nucléaire 1999 23 259-269 Les techniques de neuro-navigation ont rendu plus pressante la demande du neurochirurgien à cerner les zones à risque au niveau du cortex cérébral. L'IRMf basée sur le contraste BOLD est un moyen efficace de répondre à cette attente. Sa maîtrise dans le cadre de la cartographie cérébrale fonctionnelle préopératoire (CCFP) est encore difficile et nécessite la quadruple compétence du cogniticien, imageur, statisticien et neurochirurgien. Le traitement informatique des données représente la part la plus critique de la technique. Pour ce qui est de l'interprétation d'un examen de CCFP, il est intéressant de privilégier la sensibilité au regard de la spécificité. De plus, une discussion critique fait apparaître que la résolution spatiale de la technique ne semble présenter une bonne sensibilité qu'en prenant en compte une marge d'erreur de 5 à 20 mm autour du site d'activation. Enfin, l'activation d'une aire cérébrale ne signifie pas forcément l'implication de celle-ci dans l'exécution d'une tâche. Moyennant ces limitations, la CCFP semble générer des résultats reproductibles et robustes même dans des conditions a priori défavorables (oedème, malformation artérioveineuse...). http://cat.inist.fr/?aModele=afficheN&cpsidt=1984877 Français Jack RFoucher Marc-EtienneMeyer DanielGounot PierreKerli ChristianScheiber Izzie JNamer DanielGrucker article 1 The Lancet 1999 353 981 http://www.ncbi.nlm.nih.gov/pubmed/10459911 LaurentVercueil Jack RFoucher