Active clinical trials for "Hallucinations"

Antipsychotic drugs are characterized by blocking dopaminergic D2 receptors. They have been found to be effective and safe for the treatment of schizophrenia, bipolar disorders, depressive episodes associated with bipolar disorder, or psychotic symptoms in the context of Parkinson's disease. Atypical antipsychotics have lower blocking potency on D2 receptors, at the time that interact with serotoninergic, adrenergic and histaminergic receptors, among others. Quetiapine extended-release has the same clinical efficacy as the immediate-release formulation, but reduces the amount of daily doses, possibly contributing to increased treatment adherence. The purpose of this registry is to explore adherence to treatment, the occurrence of adverse drug reactions and the clinical outcomes in a sample of patients under treatment with atypical antipsychotics in several Central American countries. For this study, clinical data will be extracted from the medical records of 1000 patients with schizophrenia, depressive disorders or Parkinson's Disease with hallucinations. Occurrence of adverse drug reactions, namely weight gain, somnolence, extrapyramidal reactions and symptoms of orthostatic hypotension; adherence to treatment; and changes in quality of life and clinical status will be assessed during the first 8 weeks of treatment.

This study aims to describe hallucinations prevalence in a sample of patients affected by Parkinson's disease and consulting in an outpatient facility. An unique one hour interview will be offered to volunteers patients. Patients participating to the study will be asked to answer a semi-structured questionnaire searching for hallucinations of all modalities, minor psychotic symptoms and delusions. Psychometric scales will be assessed to search for depressive symptoms, cognitive impairment and specific personality characteristics. The study hypothesis is that hallucinations prevalence in Parkinson's disease is underestimated and is higher than usually described in the scientific literature when all hallucinations modalities and minor hallucinatory phenomenons are searched for.

Parkinson's disease is characterized not only by motor symptoms but also by psycho-behavioral symptoms including Visual Hallucinations (VH) and illusions (I), that are generally associated with a severe functional impairment and a bad prognosis for patients. Visual Hallucinations are defined by a visual perception without any real objet to perceive, whereas illusions are defined by a wrong perceptions of an object that is really present. In most of studies investigating the pathophysiology of VH in PD, no difference is made between VH and I, however different mechanisms could lead to the emergence of these two phenomenon, with different prognosis. Investigator hypothesize that illusions could be related to a visual impairment, maybe at the retinal level, known to be impaired in PD, whereas Visual hallucinations would be due to a more widespread impairment affecting higher levels visuo-perceptive and cognitive functions.

Auditory verbal hallucinations (AVHs) are speech perceptions in the absence of a relevant external stimulation. Some accounts of AVHs claim that a deficit in inner speech monitoring would cause the verbal thoughts of the patient to be perceived as external voices resulting in AVHs. In order to examine whether AVHs correspond to self-generated inner speech, the present study aims at collecting speech muscle activity during covert AVHs (without articulation), overt speech and rest. Surface electromyography (sEMG) is used on schizophrenia patients and control subjects to detect any speech muscle activity during AVH.

BACKGROUND It is demonstrated that strong associations between trauma suffered in childhood and having schizophrenia, and more specifically to experience acoustic-verbal hallucinations (AVH). A second generation of research is currently examining the cognitive and affective processes likely to play a mediating role in this association. These mediators appear to include early maladaptive personality patterns and dissociative experiences. Although these factors have most often been explored separately, recent research indicates that they could be associated, and thus contribute to AVH. More specifically, another study has shown that the association between childhood trauma and predisposition to AVH is not direct but depends on cognitive factors including the impact of violence suffered during childhood on early maladaptive schemas and dissociation. However, this study was carried out on a non-clinical sample of subjects with a predisposition to AVH. OBJECTIVES: testing a structural model of AVH, childhood trauma, early maladaptive schemas and dissociative symptoms in large multicentric sample of inpatients diagnosed with schizophrenia and AVH (n=350). Secondary objectives are (i) test in the model the role of all the early patterns described by Jeffrey Young instead of targeting only the schemes that are part of the model tested in previous study as the one by Bortolon and colleagues, (ii) compare the quality of the adjustment of the confirmatory model to the quality of the adjustment of the exploratory model. METHODS: one single visit in which subjects will receive self-reported questionnaires (Childhood trauma questionnaire, The Young schema questionnaire short form, Dissociative experiences scale, Launay-Slade hallucination scale and Cardiff Anomalous Perceptions Scale. ANALYSES: Structural equation model performed additional analysis using Partial Least Squares Structural Equation Modelling. The primary endpoint corresponds to significant associations between the variables. The quality of the model will be assessed using a fit quality measure. The secondary endpoints are significant associations between the different variables (p <0.05) and the model quality assessed with a quality measure of the fit. MAIN HYPOTHESIS: the association between childhood trauma and predisposition to AVH is not direct, but depends on the impact of violence suffered during childhood on early maladaptive schemas and dissociative symptoms in patients with schizophrenia.

Investigation on how robotically mediated sensorimotor stimulation induces and triggers presence hallucinations in different clinical groups of parkinsonian patients, and in aged-matched controls

Psychotic symptoms (hallucinations and delusions) are present in several psychiatric and neurological disorders as well as in the general population. Effective treatment strategies for these symptoms in all patients are lacking and treatment-response can presently not be predicted. To date, the exact pathophysiological mechanism of these symptoms remains unknown. By investigating (subtypes) of hallucinations and delusions in all populations, a common pathway may be found, leading to more effective treatment options. Alternatively, different subtypes may be associated with different pathophysiological mechanisms.

Rationale: Hallucinations occur in many patients with different kinds of diseases, including psychiatric, neurological and perceptual impairment. The origin of these hallucinations is only partly understood. This prevents correct prediction of treatment response and hampers the development of new, more effective treatment strategies. Different subtypes of hallucinations resulting from different neuropathology may exist across diagnostic entities, and be responsive to different treatment strategies. Understanding the origin of these subtypes with use of fMRI and EEG can help to make rational treatment decisions on an individual basis and enhance the development of innovative treatment paradigms. Objective: The primary objective is to find specific abnormalities on resting state fMRI related to the pathophysiology of different subtypes of hallucinations. Secondary objectives are to find EEG connectivity measures that are related to the pathophysiology of different subtypes of hallucinations, reveal correlating patterns of EEG and fMRI that underlie the experience of hallucinations across different disorders, and to examine the frequency of spontaneous synchronized burst activations in auditory and visual cortices using fMRI. Study design: The investigators intend to examine neural correlates of hallucinations over different disorders using resting state EEG, fMRI and sMRI in an observational study. Study population: A total of 140 hallucinating patients will be included, 20 of each of the 7 different diagnostic groups. As a control group, 140 non-hallucinating patients with the same disorder of similar severity will be included. Main study parameters/endpoints: The main study endpoint is the difference in resting state correlates as measured with fMRI between hallucinating and non-hallucinating participants and between hallucinating individuals of different subtypes, namely: connectivity within the DMN and connectivity of the DMN to sensory cortices and the hippocampal-amygdala complex. Nature and extent of the burden and risks associated with participation, benefit and group relatedness: Participation in the study will entail an MRI scan of 40 minutes and an EEG measurement of 5 minutes. Total visit time, including preparations, will be approximately 2,5 hours. The risks associated with participation and the benefits to the individuals are negligible. The potential benefit to society in the future is considerable if the findings lead to optimization of treatment strategies and treatment response.

Investigation on how robotically mediated sensorimotor stimulation induces and triggers presence hallucinations in patients with Parkinson disease

Occurrence of visual hallucinations (VHs) in schizophrenia depend in part on disorders in the processing of late visual information (Top-Down). The broader question of how these top-down mechanisms (cognitive and / or emotional mechanisms) are involved in the occurrence of VHs remains to be specified and very few behavioral studies have so far been interested. The investigators propose to study the implication of Top-Down mechanisms in the visual hallucinatory manifestations, more specifically in the processing of ambiguous stimuli during an emotional priming task. Schizophrenia patients with VHs would have more false visual perceptions in the treatment of ambiguous stimuli than schizophrenia patients with auditory hallucinations or no hallucinations (AH/NH) and healthy controls.