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1.
Psychiatry Res ; 236: 199-201, 2016 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-26778629

RESUMEN

The reduced metabolic activity in the prefrontal brain lobes, so-called hypofrontality, is associated with increased electrophysiological delta-band activity. Schizophrenia inpatients (N=35) received sham-controlled 10Hz rTMS over the left dorsolateral prefrontal cortex in a randomised design. After treatment, the resting electroencephalography revealed a significant decrease in the delta-band activity, which originated in the right prefrontal cortex and correlated with improvements in facial affect recognition.


Asunto(s)
Electroencefalografía , Esquizofrenia/terapia , Psicología del Esquizofrénico , Estimulación Magnética Transcraneal/métodos , Adulto , Encéfalo/fisiopatología , Ritmo Delta , Reconocimiento Facial , Femenino , Humanos , Masculino , Corteza Prefrontal/fisiopatología
2.
Brain Stimul ; 7(4): 559-63, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24857264

RESUMEN

OBJECTIVE: Facial affect recognition, a basic building block of social cognition, is often impaired in schizophrenia. Poor facial affect recognition is closely related to poor functional outcome; however, neither social cognitive impairments nor functional outcome are sufficiently improved by antipsychotic drug treatment alone. Adjunctive repetitive transcranial magnetic stimulation (rTMS) has been shown to enhance cognitive functioning in both healthy individuals and in people with neuropsychiatric disorders and to ameliorate clinical symptoms in psychiatric disorders, but its effects on social cognitive impairments in schizophrenia have not yet been studied. Therefore, we evaluated the effects of sham-controlled rTMS on facial affect recognition in patients with chronic schizophrenia. METHOD: Inpatients (N = 36) on stable antipsychotic treatment were randomly assigned to double-blind high-frequency (10 Hz) rTMS or sham stimulation for a total of ten sessions over two weeks. In the verum group, each session consisted of 10 000 stimuli (20 trains of 5 s) applied over the left dorsolateral prefrontal cortex at 110% of motor threshold. Facial affect recognition was assessed before (T0) and after (T1) the ten sessions. RESULTS: Facial affect recognition improved significantly more after rTMS (accuracy change: mean = 8.9%, SD = 6.0%) than after sham stimulation (mean = 1.6%, SD = 3.5; Cohen's d = 1.45). There was no correlation with clinical improvement. CONCLUSION: Our results indicate that prefrontal 10 Hz rTMS stimulation may help to ameliorate impaired facial affect recognition in schizophrenia.


Asunto(s)
Afecto , Trastornos del Conocimiento/terapia , Cognición , Expresión Facial , Esquizofrenia/terapia , Psicología del Esquizofrénico , Estimulación Magnética Transcraneal , Adulto , Trastornos del Conocimiento/complicaciones , Trastornos del Conocimiento/psicología , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Corteza Prefrontal/fisiología , Esquizofrenia/complicaciones , Esquizofrenia/fisiopatología , Adulto Joven
3.
Addict Biol ; 19(3): 486-96, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-22913370

RESUMEN

Cigarette smoking is a severe health burden being related to a number of chronic diseases. Frequently, smokers report about sleep problems. Sleep disturbance, in turn, has been demonstrated to be involved in the pathophysiology of several disorders related to smoking and may be relevant for the pathophysiology of nicotine dependence. Therefore, determining the frequency of sleep disturbance in otherwise healthy smokers and its association with degree of nicotine dependence is highly relevant. In a population-based case-control study, 1071 smokers and 1243 non-smokers without lifetime Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Axis I disorder were investigated. Sleep quality (SQ) of participants was determined by the Pittsburgh Sleep Quality Index. As possible confounders, age, sex and level of education and income, as well as depressiveness, anxiety, attention deficit hyperactivity, alcohol drinking behaviour and perceived stress, were included into multiple regression analyses. Significantly more smokers than non-smokers (28.1% versus 19.1%; P < 0.0001) demonstrated a disturbed global SQ. After controlling for the confounders, impaired scores in the component scores of sleep latency, sleep duration and global SQ were found significantly more often in smokers than non-smokers. Consistently, higher degrees of nicotine dependence and intensity of smoking were associated with shorter sleep duration. This study demonstrates for the first time an elevated prevalence of sleep disturbance in smokers compared with non-smokers in a population without lifetime history of psychiatric disorders even after controlling for potentially relevant risk factors. It appears likely that smoking is a behaviourally modifiable risk factor for the occurrence of impaired SQ and short sleep duration.


Asunto(s)
Trastornos del Sueño-Vigilia/etiología , Fumar/efectos adversos , Tabaquismo/complicaciones , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Alemania/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Trastornos del Sueño-Vigilia/epidemiología , Fumar/epidemiología , Tabaquismo/epidemiología , Adulto Joven
4.
Neuropsychobiology ; 68(3): 139-45, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24051542

RESUMEN

We investigated whether male inpatients with schizophrenia and a history of hands-on violent offences (forensic schizophrenic, FOS) are more impaired in emotion recognition than matched schizophrenia patients without any history of violence (general psychiatric schizophrenic, GPS). This should become apparent in performance in psychometry and in scalp event-related brain potentials (ERPs) evoked by pictures of facial affect. FOS and GPS (each n = 19) were matched concerning age, intelligence, comorbid addiction, medication and illness duration. FOS revealed significantly poorer affect recognition (AR) performance, especially of neutral and fear stimuli. Analysis of ERPs revealed a significant interaction of hemisphere, electrode position and group of the N250 component. Post hoc analysis of group effect showed significantly larger amplitudes in FOS at FC3. These results support the hypothesis that in FOS emotional faces are more salient and evoke higher arousal. Larger impairment in AR performance combined with higher salience and arousal may contribute to the occurrence of violent acts in schizophrenia patients.


Asunto(s)
Afecto/fisiología , Encéfalo/fisiología , Expresión Facial , Reconocimiento en Psicología/fisiología , Esquizofrenia/fisiopatología , Adulto , Mapeo Encefálico , Electroencefalografía , Emociones/fisiología , Potenciales Evocados , Humanos , Masculino , Estimulación Luminosa , Esquizofrenia/complicaciones , Violencia
5.
Soc Neurosci ; 8(5): 505-14, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23879268

RESUMEN

Violent offenders with schizophrenia have a particularly poor performance level in facial affect recognition. Nineteen male schizophrenia patients, who had been committed to psychiatric hospital detention because of violent offences and lack of criminal responsibility, were recruited to receive the Training of Affect Recognition (TAR). Performance in the Pictures of Facial Affect (PFA)-test and event-related potentials (ERPs) were registered in a pre-post-treatment design. TAR was feasible with a very high treatment effect (Cohen's d = 1.88), which persisted for 2 months post-treatment. ERPs remained unchanged post- vs. pre-treatment, while low resolution brain electromagnetic tomography (LORETA) revealed activation decreases in left-hemispheric parietal-temporal-occipital regions at 172 msec and activation increases in right dorsolateral prefrontal cortex and anterior cingulate at 250 msec. Possibly, violent offenders with schizophrenia are particularly amenable to TAR because of a high level of dysfunction at baseline. Post- vs. pre-treatment changes of neural activity (LORETA) may mirror a gain of efficiency in structural face decoding and a shift towards a more reflective mode of emotional face decoding, relying on increased frontal brain activity. Functional magnetic resonance imaging (BOLD-fMRI) -data from another study further supports this notion. TAR treatment might enable subjects with schizophrenia and a disposition to violence to reach a higher degree of deliberation of their reactive behavior to facial affect stimuli.


Asunto(s)
Terapia Conductista , Potenciales Evocados Visuales/fisiología , Reconocimiento en Psicología/fisiología , Esquizofrenia/rehabilitación , Psicología del Esquizofrénico , Violencia/psicología , Adulto , Análisis de Varianza , Encéfalo/diagnóstico por imagen , Electroencefalografía , Cara , Expresión Facial , Femenino , Estudios de Seguimiento , Humanos , Masculino , Pruebas Neuropsicológicas , Estimulación Luminosa , Escalas de Valoración Psiquiátrica , Psicometría , Radiografía , Esquizofrenia/patología , Tomógrafos Computarizados por Rayos X
6.
Eur Arch Psychiatry Clin Neurosci ; 263(6): 519-27, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23081705

RESUMEN

More than 80 % of patients diagnosed with schizophrenia are nicotine-dependent. Self-medication of cognitive deficits and an increased vulnerability to stress are discussed as promoting factors for the development of nicotine dependence. However, the effects of nicotine on social cognition and subjective stress responses in schizophrenia are largely unexplored. A 2 × 2-factorial design (drug × group) was used to investigate the effects of nicotine versus placebo in smoking schizophrenia patients and healthy controls after 24 h of abstinence from smoking. Participants performed a facial affect recognition task and a semi-standardized role-play task, after which social competence and self-reported stress during social interaction were assessed. Data analysis revealed no significant group differences in the facial affect recognition task. During social interaction, healthy controls showed more non-verbal expressions and a lower subjective stress level than schizophrenia patients. There were no significant effects of nicotine in terms of an enhanced recognition of facial affect, more expressive behaviour or reduced subjective stress during social interaction. While schizophrenia patients unexpectedly recognized facial affect not significantly worse than healthy controls, the observed group differences in subjective stress and non-verbal expression during social interaction in the role-play situation are in line with previous findings. Contrary to expectations derived from the self-medication hypothesis, nicotine showed no significant effects on the dependent variables, perhaps because of the dosage used and the delay between the administration of nicotine and the performance of the role-play.


Asunto(s)
Trastornos del Conocimiento/tratamiento farmacológico , Nicotina/uso terapéutico , Agonistas Nicotínicos/uso terapéutico , Conducta Social , Estrés Psicológico , Adulto , Análisis de Varianza , Trastornos del Conocimiento/etiología , Cotinina/sangre , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Esquizofrenia/complicaciones , Psicología del Esquizofrénico , Autoinforme , Fumar/psicología , Estadística como Asunto , Estrés Psicológico/tratamiento farmacológico , Estrés Psicológico/etiología , Estrés Psicológico/psicología , Adulto Joven
7.
Neuropharmacology ; 64: 197-204, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22766391

RESUMEN

In this multicenter, double-blind, placebo-controlled, randomized, four way cross-over proof-of-mechanism study, we tested the effect of the positive allosteric α7 nicotinic acetylcholine receptor (nAChR) modulator JNJ-39393406 in a key translational assay (sensory P50 gating) in 39 regularly smoking male patients with schizophrenia. All patients were clinically stable and JNJ-39393406 was administered as an adjunct treatment to antipsychotics. No indication was found that JNJ-39393406 has the potential to reverse basic deficits of information processing in schizophrenia (sensory P50 gating) or has a significant effect on other tested electrophysiological markers (MMN, P300 and quantitative resting EEG). Sensitivity analyses including severity of disease, baseline P50 gating, medication and gene variants of the CHRNA7 gene did not reveal any subgroups with consistent significant effects. It is discussed that potential positive effects in subgroups not present or not large enough in the current study or upon chronic dosing are possible, but unlikely to be developed. This article is part of a Special Issue entitled 'Cognitive Enhancers'.


Asunto(s)
Trastornos del Conocimiento/prevención & control , Terapia Molecular Dirigida , Agonistas Nicotínicos/uso terapéutico , Nootrópicos/uso terapéutico , Receptores Nicotínicos/metabolismo , Esquizofrenia/tratamiento farmacológico , Filtrado Sensorial/efectos de los fármacos , Adulto , Regulación Alostérica , Antipsicóticos/uso terapéutico , Trastornos del Conocimiento/etiología , Estudios Cruzados , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Drogas en Investigación/administración & dosificación , Drogas en Investigación/efectos adversos , Drogas en Investigación/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Agonistas Nicotínicos/administración & dosificación , Agonistas Nicotínicos/efectos adversos , Nootrópicos/administración & dosificación , Nootrópicos/efectos adversos , Receptores Nicotínicos/química , Esquizofrenia/fisiopatología , Fumar , Adulto Joven , Receptor Nicotínico de Acetilcolina alfa 7
8.
Psychiatry Res ; 203(1): 83-8, 2012 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-22901626

RESUMEN

The aim of this study was to investigate the functional basis of frequently described cognitive deficits in schizophrenia patients by exploring the electrophysiological correlates of planning processes during performance of the Trail-Making Test-B (TMT-B). Via concurrent recording of behavioral test performance, exploratory eye movements and electrical brain activity functional components critical for task performance were extracted and characterized. Participants comprised 12 first episode patients and 12 matched healthy controls who were examined with concurrent infrared oculography and electroencephalography (EEG) while they carried out a computerized TMT-B. The performance process was segmented into planning and monitoring phases based on the interaction of eye and hand movements. Brain electrical activity was analyzed using low-resolution electromagnetic brain tomography (LORETA). During planning fixations compared to monitoring fixations, both groups showed enhanced current density in dorsolateral prefrontal cortex, cingulate gyrus and inferior parietal lobe. Concurrent with poorer performance, schizophrenia patients exhibited hypoactivity within prefrontal brain areas during planning. Thus, poorer performance in schizophrenia seems to be attributable to impaired planning behavior based on hypoactivity of prefrontal areas, involved in the temporal scheduling of deliberate actions as well as visuomotor integration.


Asunto(s)
Corteza Cerebral/fisiopatología , Función Ejecutiva , Desempeño Psicomotor , Esquizofrenia/fisiopatología , Adulto , Estudios de Casos y Controles , Electroencefalografía , Medidas del Movimiento Ocular , Movimientos Oculares , Femenino , Humanos , Masculino , Prueba de Secuencia Alfanumérica
9.
Eur Addict Res ; 18(5): 246-52, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22584873

RESUMEN

BACKGROUND: Neuropeptide Y (NPY) is a strong candidate gene regarding the pathophysiology of tobacco dependence. It has been associated with various addictive and psychiatric disorders, and closely interacts with the brain reward system. The aim of the present study was to test for association between a functional genetic variant in the NP-Y promoter gene (SNP rs16147) and tobacco smoking. METHODS: In a population-based case-control multicenter study designed for tobacco addiction research, a total of 550 Caucasian current smokers, and 544 never-smokers were genotyped for SNP rs16147 and behaviorally characterized with the State-Trait Anxiety Inventory (STAI). RESULTS: Subjects with TT genotype of the SNP rs16147 were significantly more frequently smokers than never-smokers (p = 0.046). In addition, TT genotype exhibited increased state anxiety scores compared to carriers of the C allele (p = 0.037). CONCLUSIONS: Our results provide evidence for an involvement of the functionally relevant SNP rs16147 in the pathophysiology of tobacco dependence. Further studies are needed to confirm our findings.


Asunto(s)
Neuropéptido Y/genética , Fumar/genética , Tabaquismo/genética , Adulto , Alelos , Ansiedad/genética , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas/genética , Población Blanca/genética
10.
Proc Natl Acad Sci U S A ; 109(16): 6271-6, 2012 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-22451930

RESUMEN

Several polymorphisms of the transcription factor 4 (TCF4) have been shown to increase the risk for schizophrenia, particularly TCF4 rs9960767. This polymorphism is associated with impaired sensorimotor gating measured by prepulse inhibition--an established endophenotype of schizophrenia. We therefore investigated whether TCF4 polymorphisms also affect another proposed endophenotype of schizophrenia, namely sensory gating assessed by P50 suppression of the auditory evoked potential. Although sensorimotor gating and sensory gating are not identical, recent data suggest that they share genetic fundamentals. In a multicenter study at six academic institutions throughout Germany, we applied an auditory P50 suppression paradigm to 1,821 subjects (1,023 never-smokers, 798 smokers) randomly selected from the general population. Samples were genotyped for 21 TCF4 polymorphisms. Given that smoking is highly prevalent in schizophrenia and affects sensory gating, we also assessed smoking behavior, cotinine plasma concentrations, exhaled carbon monoxide, and the Fagerström Test (FTND). P50 suppression was significantly decreased in carriers of schizophrenia risk alleles of the TCF4 polymorphisms rs9960767, rs10401120rs, rs17597926, and 17512836 (P < 0.0002-0.00005). These gene effects were modulated by smoking behavior as indicated by significant interactions of TCF4 genotype and smoking status; heavy smokers (FTND score ≥ 4) showed stronger gene effects on P50 suppression than light smokers and never-smokers. Our finding suggests that sensory gating is modulated by an interaction of TCF4 genotype with smoking, and both factors may play a role in early information processing deficits also in schizophrenia. Consequently, considering smoking behavior may facilitate the search for genetic risk factors for schizophrenia.


Asunto(s)
Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/genética , Polimorfismo de Nucleótido Simple , Esquizofrenia/genética , Esquizofrenia/fisiopatología , Filtrado Sensorial/fisiología , Fumar/fisiopatología , Factores de Transcripción/genética , Adulto , Análisis de Varianza , Cotinina/sangre , Electroencefalografía , Potenciales Evocados Auditivos/fisiología , Femenino , Frecuencia de los Genes , Genotipo , Geografía , Alemania , Humanos , Desequilibrio de Ligamiento , Masculino , Factores de Riesgo , Fumar/sangre , Factor de Transcripción 4
11.
J Cogn Neurosci ; 24(8): 1682-94, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22452559

RESUMEN

In a previous oddball task study, it was shown that the inclusion of electrophysiology (EEG), that is, single-trial P3 ERP parameters, in the analysis of fMRI responses can detect activation that is not apparent with conventional fMRI data modeling strategies [Warbrick, T., Mobascher, A., Brinkmeyer, J., Musso, F., Richter, N., Stoecker, T., et al. Single-trial P3 amplitude and latency informed event-related fMRI models yield different BOLD response patterns to a target detection task. Neuroimage, 47, 1532-1544, 2009]. Given that P3 is modulated by nicotine, including P3 parameters in the fMRI analysis might provide additional information about nicotine effects on brain function. A 1-mg nasal nicotine spray (0.5 mg each nostril) or placebo (pepper) spray was administered in a double-blind, placebo-controlled, within-subject, randomized, cross-over design. Simultaneous EEG-fMRI and behavioral data were recorded from 19 current smokers in response to an oddball-type visual choice RT task. Conventional general linear model analysis and single-trial P3 amplitude informed general linear model analysis of the fMRI data were performed. Comparing the nicotine with the placebo condition, reduced RTs in the nicotine condition were related to decreased BOLD responses in the conventional analysis encompassing the superior parietal lobule, the precuneus, and the lateral occipital cortex. On the other hand, reduced RTs were related to increased BOLD responses in the precentral and postcentral gyri, and ACC in the EEG-informed fMRI analysis. Our results show how integrated analyses of simultaneous EEG-fMRI data can be used to detect nicotine effects that would not have been revealed through conventional analysis of either measure in isolation. This emphasizes the significance of applying multimodal imaging methods to pharmacoimaging.


Asunto(s)
Encéfalo/fisiología , Electroencefalografía/métodos , Potenciales Relacionados con Evento P300/fisiología , Imagen por Resonancia Magnética/métodos , Nicotina/farmacología , Adulto , Encéfalo/metabolismo , Capsicum/efectos de los fármacos , Método Doble Ciego , Electroencefalografía/instrumentación , Femenino , Giro del Cíngulo/metabolismo , Giro del Cíngulo/fisiología , Humanos , Imagen por Resonancia Magnética/instrumentación , Masculino , Rociadores Nasales , Pruebas Neuropsicológicas , Nicotina/administración & dosificación , Lóbulo Occipital/metabolismo , Lóbulo Occipital/fisiología , Lóbulo Parietal/metabolismo , Lóbulo Parietal/fisiología , Placebos , Distribución Aleatoria , Fumar/metabolismo , Percepción Visual/fisiología
12.
Schizophr Bull ; 38(5): 1021-9, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21402721

RESUMEN

BACKGROUND: Impairments in facial affect recognition are well documented in individuals suffering from schizophrenia. The aim of the present study was to characterize potential impairments in affect recognition and their electrophysiological correlates in at-risk individuals. Such characterization should add to the question whether the neural processes underlying facial affect recognition deficits might be part of a basic neural dysfunction reflecting a vulnerability factor of schizophrenia. METHODS: To test facial affect recognition, a digitized series of pictures of facial affect, previously used in related studies, was presented to 37 at-risk individuals and 32 healthy controls. Simultaneously, event-related potentials (ERPs) were recorded to investigate electrophysiological activity during the task. RESULTS: At-risk individuals showed significant impairments in facial affect recognition and reduced amplitudes in the ERP components P100, N170, and N250. Furthermore, prodromal signs in these individuals were associated with a poorer task performance and a diminished N250 amplitude. CONCLUSIONS: The findings suggest that impairments in facial affect recognition precede the onset of the initial psychotic episode. The impairments are associated with neurophysiological abnormalities similar to those observed in manifest schizophrenia and therefore may serve as indicators of vulnerability for developing schizophrenia.


Asunto(s)
Afecto/fisiología , Electroencefalografía , Expresión Facial , Predisposición Genética a la Enfermedad/genética , Reconocimiento Visual de Modelos/fisiología , Reconocimiento en Psicología/fisiología , Esquizofrenia/genética , Esquizofrenia/fisiopatología , Trastorno de la Personalidad Esquizotípica/genética , Trastorno de la Personalidad Esquizotípica/fisiopatología , Procesamiento de Señales Asistido por Computador , Adolescente , Adulto , Diagnóstico Precoz , Potenciales Evocados/genética , Potenciales Evocados/fisiología , Femenino , Lóbulo Frontal/fisiopatología , Humanos , Masculino , Factores de Riesgo , Estadística como Asunto , Adulto Joven
13.
Neuroimage ; 58(2): 508-25, 2011 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-21723949

RESUMEN

BACKGROUND: Behavioral and electrophysiological human ketamine models of schizophrenia are used for testing compounds that target the glutamatergic system. However, corresponding functional neuroimaging models are difficult to reconcile with functional imaging and electrophysiological findings in schizophrenia. Resolving the discrepancies between different observational levels is critical to understand the complex pharmacological ketamine action and its usefulness for modeling schizophrenia pathophysiology. METHODS: We conducted a within-subject, randomized, placebo-controlled pharmacoimaging study in twenty-four male volunteers. Subjects were given low-dose S-ketamine (bolus prior to functional imaging: 0.1mg/kg during 5min, thereafter continuous infusion: 0.015625mg/kg/min reduced by 10% every ten minutes) or placebo while performing a visual oddball task during simultaneous functional magnetic resonance imaging (fMRI) with continuous recording of event-related potentials (P300) and electrodermal activity (EDA). Before and after intervention, psychopathological status was assessed using the Positive and Negative Syndrome Scale (PANSS) and the Altered State of Consciousness (5D-ASC) Rating Scale. RESULTS: P300 amplitude and corresponding BOLD responses were diminished in the ketamine condition in cortical regions being involved in sensory processing/selective attention. In both measurement modalities separation of drug conditions was achieved with area under the curve (AUC) values of up to 0.8-0.9. Ketamine effects were also observed in the clinical, behavioral and peripheral physiological domains (Positive and Negative Syndrome Scale, reaction hit and false alarm rate, electrodermal activity and heart rate) which were in part related to the P300/fMRI measures. CONCLUSION: The findings from our ketamine experiment are consistent across modalities and directly related to observations in schizophrenia supporting the validity of the model. Our investigation provides the first prototypic example of a pharmacoimaging study using simultaneously acquired fMRI/EEG.


Asunto(s)
Encéfalo/efectos de los fármacos , Antagonistas de Aminoácidos Excitadores/farmacología , Ketamina/farmacología , Desempeño Psicomotor/efectos de los fármacos , Percepción Visual/efectos de los fármacos , Estimulación Acústica , Adulto , Análisis de Varianza , Estudios Cruzados , Interpretación Estadística de Datos , Método Doble Ciego , Electroencefalografía , Potenciales Relacionados con Evento P300/efectos de los fármacos , Potenciales Evocados Auditivos/fisiología , Femenino , Lateralidad Funcional/efectos de los fármacos , Lateralidad Funcional/fisiología , Respuesta Galvánica de la Piel/efectos de los fármacos , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Oxígeno/sangre , Adulto Joven
14.
Addict Biol ; 16(4): 638-53, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21521423

RESUMEN

Tobacco smoking is a major risk factor for most of the diseases leading in mortality. Nicotine dependence (ND), which sustains regular smoking, is now acknowledged to be under substantial genetic control with some environmental contribution. At present, however, genetic studies on ND are mostly conducted in populations that have been poorly characterized with regard to ND-related phenotypes for the simple reason that the respective populations were not primarily collected to study ND. The German multi-centre study 'Genetics of Nicotine Dependence and Neurobiological Phenotypes', which is funded by the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG) as part of the Priority Program (Schwerpunktprogramm) SPP1226: 'Nicotine-Molecular and Physiological Effects in CNS', was intended to overcome some of these inherent problems of current genetic studies of ND. The multi-centre study is a population-based case-control study of smokers and never-smokers (n = 2396). The study was unique worldwide because it was the first large-scale genetic study specifically addressing ND with the collection of a wide range of environmental, psychosocial and neurobiological phenotypes. Study design and major population characteristics with emphasis on risk prediction of smoking status were presented in this paper.


Asunto(s)
Fumar/genética , Tabaquismo/genética , Adulto , Consumo de Bebidas Alcohólicas/genética , Trastornos de Ansiedad/genética , Trastorno por Déficit de Atención con Hiperactividad/genética , Estudios de Casos y Controles , Comorbilidad , Trastorno Depresivo/genética , Conducta Exploratoria , Femenino , Predisposición Genética a la Enfermedad/genética , Humanos , Masculino , Persona de Mediana Edad , Inventario de Personalidad/estadística & datos numéricos , Fenotipo , Psicometría , Medición de Riesgo , Medio Social
15.
Horm Behav ; 60(1): 58-64, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21376724

RESUMEN

Preclinical and clinical data suggest modulating effects of appetite-regulating hormones and stress perception on food intake. Nicotine intake also interferes with regulation of body weight. Especially following smoking cessation gaining weight is a common but only partially understood consequence. The aim of this study was to examine the interaction between smoking habits, the appetite regulating hormone leptin, negative affectivity, and stress vulnerability on eating behavior in a clinical case-control study under standardized conditions. In a large population-based study sample, we compared leptin and cortisol plasma concentrations (radioimmunoassay) between current tobacco smokers with high cognitive restraint and disinhibition in eating behavior and smokers scoring low in both categories as assessed with the Three Factor Eating Questionnaire (TFEQ; Stunkard & Messick, 1985). As a measure for smoking effects on the stress axis, the saliva cortisol concentrations were compared before and after nicotine smoking. Additionally, stress perception was assessed with the Perceived Stress Scale (PSS), symptoms of depression and anxiety with the Beck Depression Inventory (BDI) and the State Trait Anxiety Inventory (STAI). In smokers showing high cognitive restraint and disinhibition we found significantly higher leptin concentrations than in the group of smokers scoring low in both categories. Furthermore there was a significant group difference in saliva cortisol concentrations after nicotine intake. Smokers showing high cognitive restraint and disinhibition were also characterized by significantly higher scores in the STAI, the PSS and the BDI. Our results suggest that smokers with a pathological eating behavior show an impaired neuroendocrine regulation of appetite and are prone to experience higher levels of stress and negative affectivity. This interaction of behavioral and neuroendocrinological factors may constitute a high risk condition for gaining weight following smoking cessation.


Asunto(s)
Conducta Alimentaria/psicología , Cese del Hábito de Fumar/psicología , Fumar/sangre , Fumar/psicología , Aumento de Peso/fisiología , Adulto , Ansiedad/sangre , Ansiedad/epidemiología , Ansiedad/fisiopatología , Estudios de Casos y Controles , Conducta Alimentaria/fisiología , Femenino , Humanos , Hidrocortisona/sangre , Hidrocortisona/fisiología , Leptina/sangre , Leptina/fisiología , Masculino , Persona de Mediana Edad , Riesgo , Saliva/química , Fumar/epidemiología , Cese del Hábito de Fumar/estadística & datos numéricos , Estrés Psicológico/epidemiología , Estrés Psicológico/fisiopatología , Encuestas y Cuestionarios , Adulto Joven
16.
Addict Biol ; 16(3): 485-98, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21392171

RESUMEN

P50 gating is a major functional biomarker in research on schizophrenia and other psychiatric conditions with high smoking prevalence. It is used as endophenotype for studying nicotinic systems genetics and as surrogate endpoint measure for drug development of nicotinic agonists. Surprisingly, little is known about P50 gating in the general population and the relationship to smoking-related characteristics. In this multicenter study at six academic institutions throughout Germany, n=907 never-smokers (NS<20 cigarettes/lifetime), n=463 light smokers (LS) with Fagerström Test for Nicotine Dependence (FTND)≥4 and n=353 heavy smokers (HS, FTND<4) were randomly selected from the general population. As part of a standardized protocol for investigating the genetics of nicotine dependence (ND), an auditory P50 paradigm was applied. The main outcome measure was P50-amplitude difference followed by time-frequency analyses and functional imaging (sLORETA). Reduced P50 gating was found in HS compared to NS with LS taking an intermediate position-correlating with the degree of ND. sLORETA and time-frequency analyses indicate that high-frequency oscillations in frontal brain regions are particularly affected. With growing age, P50 gating increased in (heavy) smokers. This is the first large-scale study (normative sample data) on P50 sensory gating and smoking in the general population. Diminished gating of P50 and associated high-frequency oscillations in the frontal brain region are indications of a deficient inhibitory cortical function in nicotine-dependent smokers. The suitability and application of sensory P50 gating as functional biomarker with regard to genetic and pharmacological studies is discussed.


Asunto(s)
Corteza Cerebral/fisiopatología , Potenciales Evocados Auditivos/genética , Potenciales Evocados Auditivos/fisiología , Filtrado Sensorial/fisiología , Fumar/genética , Fumar/fisiopatología , Adolescente , Adulto , Mapeo Encefálico , Electroencefalografía , Femenino , Neuroimagen Funcional , Humanos , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Valores de Referencia , Procesamiento de Señales Asistido por Computador , Fumar/psicología , Adulto Joven
17.
Biol Psychiatry ; 69(10): 959-66, 2011 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-21167475

RESUMEN

BACKGROUND: To develop risk-adapted prevention of psychosis, an accurate estimation of the individual risk of psychosis at a given time is needed. Inclusion of biological parameters into multilevel prediction models is thought to improve predictive accuracy of models on the basis of clinical variables. To this aim, mismatch negativity (MMN) was investigated in a sample clinically at high risk, comparing individuals with and without subsequent conversion to psychosis. METHODS: At baseline, an auditory oddball paradigm was used in 62 subjects meeting criteria of a late risk at-state who remained antipsychotic-naive throughout the study. Median follow-up period was 32 months (minimum of 24 months in nonconverters, n = 37). Repeated-measures analysis of covariance was employed to analyze the MMN recorded at frontocentral electrodes; additional comparisons with healthy controls (HC, n = 67) and first-episode schizophrenia patients (FES, n = 33) were performed. Predictive value was evaluated by a Cox regression model. RESULTS: Compared with nonconverters, duration MMN in converters (n = 25) showed significantly reduced amplitudes across the six frontocentral electrodes; the same applied in comparison with HC, but not FES, whereas the duration MMN in in nonconverters was comparable to HC and larger than in FES. A prognostic score was calculated based on a Cox regression model and stratified into two risk classes, which showed significantly different survival curves. CONCLUSIONS: Our findings demonstrate the duration MMN is significantly reduced in at-risk subjects converting to first-episode psychosis compared with nonconverters and may contribute not only to the prediction of conversion but also to a more individualized risk estimation and thus risk-adapted prevention.


Asunto(s)
Encéfalo/fisiopatología , Variación Contingente Negativa/fisiología , Trastornos Psicóticos/diagnóstico , Trastornos Psicóticos/fisiopatología , Estimulación Acústica/métodos , Adolescente , Adulto , Electroencefalografía , Femenino , Lateralidad Funcional , Humanos , Masculino , Pruebas Neuropsicológicas , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Escalas de Valoración Psiquiátrica , Psicoacústica , Trastornos Psicóticos/patología , Factores de Riesgo , Adulto Joven
18.
Schizophr Bull ; 37(4): 861-73, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20053865

RESUMEN

Impairments in neuropsychological functioning have been described in subjects clinically at high risk for psychosis, but the specific cognitive deficits in different clinical high-risk groups remain to be elucidated. The German Research Network on Schizophrenia employs a heuristic 2-stage model: a putatively late prodromal state (LPS), characterized by the onset of attenuated positive or brief psychotic symptoms, and an early prodromal state (EPS), mainly characterized by the presence of basic symptoms, which are predictive for psychosis within the next 10 years. A total of 205 subjects met the criteria for either an EPS or an LPS of psychosis and were assessed with a comprehensive neuropsychological test battery. Neurocognitive profiles of high-risk groups were compared with data of 87 healthy controls comparable with regard to gender, age, and premorbid verbal IQ. Patients in the LPS were impaired in all neurocognitive domains (memory/learning, executive control/processing speed, and working memory) examined, with memory being the worst. Deficits were less pronounced in patients in the EPS, with a specific deficit in the executive control/processing speed domain. Consistent with a progressive neurodevelopmental disorder, some cognitive abilities were already impaired in patients in the EPS, followed by further deterioration in the LPS. Specifically, deficits in executive control functioning were related to the presence of basic symptoms, indicating a vulnerability for psychosis. Memory deficits were associated with the onset of psychotic symptoms indicating further disease progression in the trajectory to psychosis and, thus, may be useful in predicting psychosis and targeting early intervention.


Asunto(s)
Trastornos del Conocimiento/diagnóstico , Función Ejecutiva , Trastornos de la Memoria/diagnóstico , Pruebas Neuropsicológicas/estadística & datos numéricos , Trastornos Psicóticos/diagnóstico , Esquizofrenia/diagnóstico , Psicología del Esquizofrénico , Trastorno de la Personalidad Esquizotípica/diagnóstico , Adolescente , Adulto , Trastornos del Conocimiento/genética , Trastornos del Conocimiento/psicología , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Trastornos de la Memoria/genética , Trastornos de la Memoria/psicología , Estudios Prospectivos , Escalas de Valoración Psiquiátrica/estadística & datos numéricos , Psicometría/estadística & datos numéricos , Trastornos Psicóticos/genética , Trastornos Psicóticos/psicología , Reproducibilidad de los Resultados , Factores de Riesgo , Esquizofrenia/genética , Trastorno de la Personalidad Esquizotípica/genética , Trastorno de la Personalidad Esquizotípica/psicología , Adulto Joven
19.
Psychiatry Res ; 177(1-2): 32-6, 2010 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-20378181

RESUMEN

UNLABELLED: We conducted a randomized, sham-controlled repetitive transcranial magnetic stimulation (rTMS) study in chronic schizophrenia in-patients (n=35) to evaluate the therapeutic efficacy of 10 Hz stimulation. Patients, who were on stable antipsychotic treatment, were randomly assigned to the active or sham condition. In the active rTMS group, ten sessions with a total of 10,000 stimuli were applied over the left dorsolateral prefrontal cortex at 110% of motor threshold. The sham group received corresponding sham stimulation. Clinical improvement was measured by the Clinical Global Impression scale (primary outcome measure), the Global Assessment of Functioning Scale (GAF) and the Positive and Negative Symptom Scale (PANSS; secondary outcome measures). Between-group comparisons revealed no significant differences in clinical outcome variables. Only a subgroup of patients with pronounced negative symptoms developed some clinical improvement as indicated by significant changes in the GAF-scale. Besides there is some evidence for a more favourable clinical outcome within this subgroup after rTMS in the CGI-S and PANSS negative scale, too. In line with earlier investigations, our results suggest a moderate - potentially clinically relevant - treatment effect of prefrontal 10 Hz rTMS stimulation in chronic patients. However, in our study this beneficial effect was restricted to subjects with pronounced negative symptoms. CLINICAL TRIAL REGISTRATION INFORMATION: ClinicalTrial.gov Identifier: NCT00169689, http://www.clinicaltrials.gov.


Asunto(s)
Esquizofrenia/fisiopatología , Esquizofrenia/terapia , Psicología del Esquizofrénico , Estimulación Magnética Transcraneal/métodos , Adulto , Análisis de Varianza , Enfermedad Crónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Evaluación de Resultado en la Atención de Salud/métodos , Escalas de Valoración Psiquiátrica , Estadística como Asunto
20.
Eur Arch Psychiatry Clin Neurosci ; 258 Suppl 5: 28-34, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18985291

RESUMEN

To add to the open question whether cognitive impairments predict clinical outcome in schizophrenia, a sample of 125 first episode patients was assessed at the onset and over one year of controlled long-term treatment within a study of the German Research Network on Schizophrenia. No relapse according to predefined criteria occurred within the first year, but a total of 29 patients fulfilled post-hoc criteria of "clinical deterioration". Impairments in cognitive functioning assessed by the Trail-Making Test B at the onset of long-term treatment differentiated between patients with vs. without later clinical deterioration and proved to be a significant predictor of the clinical course in a regression analysis outperforming initial clinical status as predictor. However, low sensitivity (72%) and specificity (51%) limit possibilities of a transfer to individual predictions. As a linear combination of neuropsychological and psychopathological variables obtained highest predictive validity, such a combination may improve the prediction of the course of schizophrenic disorders and may ultimately lead to a more efficient and comprehensive treatment planning.


Asunto(s)
Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/etiología , Pruebas Neuropsicológicas , Esquizofrenia/complicaciones , Adulto , Antipsicóticos/uso terapéutico , Estudios de Casos y Controles , Método Doble Ciego , Femenino , Haloperidol/uso terapéutico , Humanos , Modelos Logísticos , Estudios Longitudinales , Masculino , Valor Predictivo de las Pruebas , Curva ROC , Adulto Joven
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