View clinical trials related to Perceptual Disorders.
Filter by:- The efficacy of neuro-navigated rTMS for patients with schizophrenia suffering from drug-resistant multisensory hallucinations will be tested by the implementation of a double-blind randomized controlled trial (RCT) - This study will use a combination of different MRI modalities (fMRI and DTI) to define with precision rTMS brain-targets in the case of multisensory hallucinations - The investigators anticipate that multimodal MRI-guided rTMS will allow a significant improvement in the efficacy of neuromodulation treatment of refractory hallucinations
'Unilateral neglect' is a disorder that occurs regularly after stroke. It is caused by right- as well as left-sided brain lesions, but more often by right-sided lesions. Patients with this disorder neglect the contralesional side of space and/or their body. Their body axis is often shifted ipsilesionally. A specific disorder that can appear in neglect patients is 'contraversive pushing': a postural deviation to the neglected side because the patient pushes himself away from the ipsi- to the contralesional side. One of the most promising neglect interventions is prism adaptation (PA): inducing an optical shift of the visual field by means of prism glasses. This results in a modulation of brain areas involved in neglect and in an improvement of the neglect symptoms and postural deviation. Research questions: 1. Which period is best suited to maximize therapeutic effects? In this respect the effects of early and delayed PA will be compared, regarding neglect-, postural and cerebral measures. 2. Which factors lead to a less favorable treatment outcome or to therapy resistance for PA? 3. Will the impact of PA be larger if postural factors are taken into account in the prism therapy?
Background: - People with epilepsy often have auditory processing disorders that affect their ability to hear clearly and may cause problems with understanding speech and other kinds of verbal communication. Researchers are interested in developing better ways of studying what parts of the brain are affected by hearing disorders and epilepsy, and they need better clinical tests to measure how individuals process sound. These tests will allow researchers to examine and evaluate the effects of epilepsy and related disorders on speech and communication. - A procedure called a magnetoencephalography (MEG) can be used to measure the electrical currents involved in brain activity. Researchers are interested in learning whether MEG can be used to detect differences in the processing of simple sounds in patients with epilepsy, both with and without hearing impairments. Objectives: - To measure brain activity in hearing impaired persons with epilepsy and compare the results with those from people with normal hearing and epilepsy as well as people with normal hearing and no epilepsy. This research is performed in collaboration with Johns Hopkins Hospital and epilepsy patients must be candidates for surgery at Johns Hopkins. Eligibility: - Individuals between 18 to 55 years of age who (1) have epilepsy and have hearing impairments, (2) have epilepsy but do not have hearing impairments, or (3) are healthy volunteers who have neither epilepsy nor hearing impairments. - Participants with epilepsy must have developed seizures after 10 years of age, and must be candidates for grid implantation surgery at Johns Hopkins Hospital.. Design: - This study will require one visit of approximately 4 to 6 hours. - Participants will be screened with a full physical examination and medical history, along with a basic hearing test. - Participants will have a magnetic resonance imaging (MRI) scan of the brain, followed by a MEG scan to record magnetic field changes produced by brain activity. - During MEG recording, participants will be asked to listen to various sounds and make simple responses (pressing a button, moving your hand or speaking) in response to sounds heard through earphones. The MEG procedure should take between 1 and 2 hours. - Treatment at NIH is not provided as part of this protocol.
The objective of this study is to investigate whether JNJ-40411813 versus placebo reduces psychosis-like symptoms, induced by infusion of a low dose of ketamine. Effects of JNJ-40411813 on ketamine-induced symptoms will be evaluated about 3 hours after a single oral dose when the concentration of JNJ-40411813 in the blood is at its maximum and up to 24 hours after dose administration to assess the duration of a potential JNJ-40411813 effect.
Visuospatial neglect is a common neurological symptom which appears following strokes on regions of the right hemisphere of the brain. It affects patient's self representation and awareness of the space, impairing functional rehabilitation and adaptation back to a normal life. The primary purpose of this protocol is to assess the impact of 10 daily sessions of a non-invasive brain stimulation technique, low frequency repetitive Transcranial Magnetic Stimulation (rTMS), applied on the intact hemisphere of the brain to treat post stroke visuospatial neglect at the chronic stage. The hypothesis is that a regime of real but not sham rTMS on the left posterior parietal cortex of the brain will long-lastingly ameliorate visuospatial neglect in stroke patients as revealed by clinical paper-and-pencil and computer-based tests assessing search, detection and discrimination of stimuli presented in different areas of the visual field.
This study examines methods to better predict improvement of a hidden disability of functional vision, spatial neglect, following stroke. Spatial neglect is a tendency to make visual judgment and movement errors mislocating the body and objects in space. The investigators are using specialized statistical methods to compute the proportion of improvement accounted for by personal characteristics of each stroke survivor, the proportion of improvement accounted for by the unique visual-spatial errors made by each subject, and the proportion of improvement accounted for by each treatment administered. The investigators will also examine whether brain imaging predicts how rapidly improvement occurs. Lastly, the study tests whether improvements that are meaningful to the survivor can be measured in a way that still allows detection of small and scientifically eloquent performance changes.
The purpose of this research study with a randomized controlled design is to examine the effects of prism adaptation treatment on two visual-spatial recovery components. After a stroke, an "internal GPS", locating where objects or people lie in a particular area of space, may be impaired. Alternately, a stroke may impair precise visual-spatial hand and body aiming movements. The research team wishes to discover whether prism adaptation treatment (two weeks of daily 20-min sessions of goal-directed movement with prism goggles) affects visual-spatial where or aiming errors selectively after stroke. This research represents one of the first attempts to apply what we know about the brain from neuroscience research, to modern clinical rehabilitation practices.
To find out if spatial neglect following stroke and brain injury can be reduced using guanfacine, a drug that was shown to improve neglect in two stroke patients in a previous pilot study (Malhotra et al, 2006). In this trial, the effects of guanfacine will be examined in a larger number of patients, and there will also be a systematic assessment of whether the drug is only effective in patients with particular patterns of brain damage.
The aim of this study is to assess the effect of the drug rotigotine on the syndrome of hemispatial neglect and motor deficits following strokes affecting the right hemisphere of the brain.
The purpose of this research study is to learn how people distribute their visual attention when looking at objects nearby versus far away, and why vision may become distracted at near versus far distances.