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Background: Identification of the biological markers of anorexia nervosa (AN) is crucial for the development of new treatments. We aimed to determine whether AN is associated with disturbances in the nonconscious neural processing of innate signals of emotion and whether these disturbances persist after weight gain. Methods: In a retest design, 28 adolescent females with AN were tested at first admission to hospital and again after they had gained weight. Matched healthy control participants were tested at the same times. We assessed emotion-elicited event-related potentials (ERPs) during overt and covert presentation of emotion expressions, scores on an emotion-identification behavioural task, and symptom measures. We performed between and within group analyses. Results: Individuals with AN had a marked alteration in ERPs relative to healthy controls. Irrespective of the form of stimulus, early and late ERP components were significantly reduced in AN patients at baseline (when underweight) and on retest (after weight gain), especially in the temporo-occipital regions, suggesting a persistent disruption of the early automatic appraisal of salient emotional signals. Limitations: This study could have been improved with a longer standardized retest interval. Conclusion: There is likely a core, generic disturbance in AN in the early 'automatic' neural processing of emotion irrespective of weight or nutritional status. New innovative emotion-based psychologic or pharmacologic treatments targeting these nonconscious processes may prove beneficial., Introduction Anorexia nervosa (AN) is an eating disorder characterized by low body weight, an intense fear of weight gain, body image distortion and a disruption of menstrual function. (1) There [...]

Background: Schizophrenia may be understood as a disorder of neural synchrony. There is also increasing evidence that emotional and social cognitive impairments are central to this disorder. In patients with first-episode schizophrenia, we examined whether emotion perception is associated with disruptions to high-frequency (40 Hz) gamma synchrony and whether these disruptions predict selfregulatory adaptive compensations reflected in social cognitive behaviours. Methods: We obtained electroencephalography recordings from 28 patients with first-episode schizophrenia and matched healthy controls during perception of facial emotion under both conscious and nonconscious conditions. We extracted gamma-band synchrony from the electroencephalogram. We also used behavioural measures of emotion identification, emotional intelligence, negativity bias and social function, along with ratings of first-episode schizophrenia symptoms. We analyzed group differences and predicted social cognition to assess the potential contribution of medication. Results: Within 200 ms poststimulus, patients with first-episode schizophrenia showed alterations in gamma synchrony during both conscious and nonconscious emotion perception. Stimulus-locked synchrony was reduced in patients, particularly over the temporal cortex, whereas complementary enhancements in absolute gamma synchrony (independent of stimuli) were more distributed over temporal and left parieto-occipital regions. This pattern of altered synchrony predicted poor performance on each measure of social cognition among these patients. Medication dosage did not correlate significantly with either gamma synchrony or behavioural measures in this group. Limitations: Limitations to our study include the lack of comparison between medicated and unmedicated patients or between types of medication. Conclusion: These findings suggest that disruptions in integrative processing of motivationally important stimuli show promise as a potential biological marker of social cognitive impairments, present from the first episode of schizophrenia, and their outcomes., Introduction The term "schizophrenia" was initially used to refer to a "splitting of the psychic functions." (1) Recent formulations have a similar emphasis on schizophrenia as a disconnection syndrome. (2-6) [...]

Background: Although schizophrenia has been characterized by disruptions to neural synchrony, it remains unknown whether these disturbances are related to symptoms and loss of grey matter. We examined relations between 40 Hz Gamma band synchrony and grey matter in patients with schizophrenia at first episode and after 2.5 years. Methods: From an initial recruitment of 35 medicated patients with a first episode of schizophrenia, 25 patients completed clinical and oddball task-elicited Gamma synchrony within 3 months of health service contact and again after 2.5 years, 23 completed magnetic resonance imaging (MRI) at these time points, and 13 completed all sessions. We compared patients with 35 matched healthy controls. We identified early (0-150 ms) and late (250-500 ms) peaks in Gamma synchrony locked to oddball targets, and we analyzed MRI data using voxel-based morphometry. We evaluated group and test-retest differences using repeated-measures analyses of variance. Results: Compared with controls, at first contact, patients with a first episode of schizophrenia showed a disruption to the laterality of early Gamma synchrony and global reduction in late Gamma synchrony, with a corresponding loss of fronto-temporal-parietal grey matter. Gamma synchrony was increased at follow-up among patients with a first episode of schizophrenia. It related negatively to further loss of grey matter, but positively to improvement in reality distortion symptoms. These relations could not be explained by medication dose. Limitations: Our study did not include unmedicated patients or normative follow-up testing. Conclusion: Gamma synchrony may track the progression of schizophrenia from first episode. An increase in Gamma synchrony over time might reflect an attempt to adapt to a progressive loss of cortical grey matter and associated changes in cognitive and emotional function. Contexte: Bien que l'on ait caracterise la schizophrenie comme presentant des dereglements de la synchronisation neuronale, on ignore encore s'il y a un lien entre ces dereglements, les symptomes et la perte de matiere grise. Nous avons examine les liens entre la synchronisation oscillatoire a 40 Hz (gamma) et la matiere grise chez des patients atteints de schizophrenie, au moment de leur premier episode et apres 2,5 ans. Methodes : Nous avons recrute initialement 35 patients traites pharmacologiquement pour un premier episode de schizophrenie. De ce nombre, 25 patients ont subi des tests de synchronisation oscillatoire Gamma suscitee par l'execution d'une tache clinique et d'une tache inhabituelle (protocole oddball), dans les 3 mois suivant leur premiere prise de contact avec les services de sante et a nouveau apres 2,5 ans; 23 patients ont subi un test d'imagerie par resonance magnetique (IRM) lors de ces etapes et 13 ont subi tous les tests prevus. Nous avons compare les patients a 35 temoins assortis en bonne sante. Nous avons repere les pics precoces (0-150 ms) et tardifs (250-500 ms) de synchronisation gamma correspondant aux cibles du protocole oddball et nous avons analyse les resultats des IRM par morphometrie voxel a voxel. Nous avons evalue les differences entre les groupes et les differences test-retest a l'aide d'une analyse de variance appliquee aux mesures repetees. Resultats : Comparativement aux temoins, lors du premier contact avec les services de sante, les patients atteints d'un premier episode de schizophrenie ont montre un dereglement de la lateralite de la synchronisation gamma precoce et une reduction globale de la synchronisation gamma tardive, avec perte correspondante de matiere grise fronto-temporo-parietale. Au moment du suivi, la synchronisation gamma a paru amplifiee chez les patients atteints d'un premier episode de schizophrenie. Ce phenomene a ete negativement relie a une perte accrue de matiere grise, mais positivement relie a une amelioration des symptomes de distorsion de la realite. Ces liens n'ont pu etre expliques par la dose de medicament. Limites : Notre etude n'incluait aucun patient qui ne prenait pas de medicaments et ne prevoyait pas l'application de tests de suivi normatifs. Conclusion: La synchronisation gamma pourrait permettre de suivre la progression de la schizophrenie a partir d'un premier episode. Une accentuation progressive de la synchronisation gamma pourrait traduire une tentative d'adaptation a la perte graduelle de matiere grise corticale et aux anomalies des fonctions cognitives et emotionnelles qui s'ensuivent., Introduction The term "schizophrenia" was initially used by Bleuler (1) to refer to a disease process that produces a "splitting of the psychic functions." (2) Recent formulations have also focused [...]