Search results for "Schizophrenic Psychology"
showing 10 items of 105 documents
S-Ketamine-Induced NMDA Receptor Blockade during Natural Speech Production and Its Implications for Formal Thought Disorder in Schizophrenia: A Pharm…
2017
Structural and functional changes in the lateral temporal language areas have been related to formal thought disorder (FTD) in schizophrenia. Continuous, natural speech production activates the right lateral temporal lobe in schizophrenia, as opposed to the left in healthy subjects. Positive and negative FTD can be elicited in healthy subjects by glutamatergic NMDA blockade with ketamine. It is unclear whether the glutamate system is related to the reversed hemispheric lateralization during speaking in patients. In a double-blind, crossover, placebo-controlled study, 15 healthy, male, right-handed volunteers overtly described 7 pictures for 3 min each while BOLD signal changes were acquired…
Response trajectories in "real-world" naturalistically treated schizophrenia patients.
2011
Abstract Background To date, research has identified distinct antipsychotic response trajectories yet focussing on data from randomized-controlled trials (RCTs). Therefore, the heterogeneity of response in “real-world” schizophrenia patients is still unknown. Methods Antipsychotic response was evaluated in 399 patients suffering from a schizophrenia spectrum disorder within a naturalistic multicenter study of the Competence Network on Schizophrenia using latent class regression. Baseline and illness-related variables were compared between the different trajectory classes as well as currently proposed outcome definitions (early improvement, response, remission) using univariate tests. In ord…
Altered effective connectivity during working memory performance in schizophrenia: a study with fMRI and structural equation modeling
2003
The present study aimed to explore altered effective connectivity in schizophrenic patients while performing a 2-back working memory task. Twelve right-handed, schizophrenic patients treated with typical or atypical antipsychotics and 6 healthy control subjects were studied with fMRI while performing a "2-back" working memory task. Effective connectivity within a cortical-subcortical-cerebellar network for mnemonic information processing was assessed and compared between both groups. The path model included cortico-cortical connections comprising the parietal association cortex, ventrolateral prefrontal cortex (VLPFC), and the dorsolateral prefrontal cortex (DLPFC) as well as a cortico-cere…
Visuospatial processing in schizophrenia: Does it share common mechanisms with pseudoneglect?
2011
International audience; ''Schizophrenia patients demonstrate behavioural and cerebral lateralised anomalies, prompting some authors to suggest they exhibit a mild form of right unilateral neglect. To better describe and understand lateralised visuospatial anomalies in schizophrenia, three experiments were run using tasks often utilised to study visuospatial processing in healthy individuals and in neglect patients: the Behavioural Inattention Test (BIT), the manual line bisection task with and without a local cueing paradigm, the landmark task (or line bisection judgement), and the number bisection task. Although the schizophrenia patients did not exhibit the full-blown neglect syndrome, th…
The neuroendocrinological profile of roxindole, a dopamine autoreceptor agonist, in schizophrenic patients
1995
Roxindole is a potent autoreceptor-selective dopamine agonist with additional properties as a serotonin reuptake inhibitor and 5-HT1A agonist. In order to get more insight into its mode of action in various psychiatric populations, we evaluated the effects of subchronic roxindole treatment on pituitary and adrenal hormone secretion, i.e. release of prolactin, thyroid stimulating hormone (TSH), growth hormone (GH), luteinizing hormone (LH), and cortisol. Fifteen schizophrenic patients with positive and negative symptomatology, respectively, were treated with roxindole for 28 days. Both basal and thyrotropin releasing hormone (TRH) -induced prolactin secretion diminished significantly to 26.4…
Neuroendocrine response to antipsychotics: effects of drug type and gender
1999
Abstract Background: To study the influences of drug type and gender on the neuroendocrine response to neuroleptic treatment, we compared the endocrine actions of two neuroleptics with different receptor affinity profiles—a substituted benzamide, amisulpride, a selective D 2 -like dopamine antagonist; and a thioxanthene, flupenthixol, a mixed D 1 /D 2 -like antagonist also blocking serotonin, H 1 , and D 1 receptors—on anterior pituitary hormone secretion in schizophrenic patients (DSM-III-R). Methods: Blood was withdrawn at 15-min intervals to assess basal secretion of prolactin, growth hormone (GH), and thyroid-stimulating hormone (TSH). Four hundred micrograms of thyrotropin-releasing ho…
Nonlinear analysis of sleep EEG data in schizophrenia: calculation of the principal Lyapunov exponent
1995
The generating mechanism of the electroencephalogram (EEG) points to the hypothesis that EEG signals derive from a nonlinear dynamic system. Hence, the unpredictability of the EEG might be considered as a phenomenon exhibiting its chaotic character. The essential property of chaotic dynamics is the so-called sensitive dependence on initial conditions. This property can be quantified by calculating the system's first positive Lyapunov exponent, L1. We calculated L1 for sleep EEG segments of 13 schizophrenic patients and 13 control subjects that corresponded to sleep stages I, II, III, IV and REM (rapid eye movement), as defined by Rechtschaffen and Kales, for the lead positions Cz and Pz. Du…
Dose-Related Effects of Amisulpride on Five Dimensions of Psychopathology in Patients With Acute Exacerbation of Schizophrenia
2002
The present analysis investigated symptom-specific dose-response relationships of the atypical antipsychotic amisulpride (AMI) in schizophrenic patients. The effects of different AMI doses on five different symptom dimensions of the Brief Psychiatric Rating Scale (BPRS) were analyzed. Results on global efficacy and safety parameters have been previously published. Four AMI doses (100 mg/day [AMI100], 400 mg/day [AMI400], 800 mg/day [AMI800], 1200 mg/day) were compared with 16 mg haloperidol (HAL16) in a multicenter, double-blind, randomized, parallel-group, 4-week trial. A total of 319 patients with acute exacerbation of schizophrenia (DSM-III-R) were included. AMI100 was compared with the …
Auditory Mismatch Negativity and Repetition Suppression Deficits in Schizophrenia Explained by Irregular Computation of Prediction Error
2015
Background The predictive coding model is rapidly gaining attention in schizophrenia research. It posits the neuronal computation of residual variance (‘prediction error’) between sensory information and top-down expectation through multiple hierarchical levels. Event-related potentials (ERP) reflect cortical processing stages that are increasingly interpreted in the light of the predictive coding hypothesis. Both mismatch negativity (MMN) and repetition suppression (RS) measures are considered a prediction error correlates based on error detection and error minimization, respectively. Methods Twenty-five schizophrenia patients and 25 healthy controls completed auditory tasks designed to el…
Differential effects of high-dose amisulpride versus flupentixol on latent dimensions of depressive and negative symptomatology in acute schizophreni…
2002
While many acutely ill schizophrenic patients suffer from depressive symptoms, most studies on the efficacy of antipsychotic drugs focus on positive and negative symptoms. Dimensional models of schizophrenic symptoms, based on confirmatory factor analysis (CFA) using structural equation modelling, offer a methodological alternative to compare antipsychotics on empirically justified latent factors. The present report is a refined analysis of a published double-blind study on the D 2 /D 3 -selective antagonist amisulpride (ASP) versus the mixed D 1-5 /5-HT 2 antagonist flupentixol (FPX). CFA was applied to Brief Psychiatric Rating Scale, Scale for the Assessment of Negative Symptoms, Bech-Raf…