Neuroimaging Studies of Neurophysiological Phenotypes in Schizophrenia
|First Received Date ICMJE||December 18, 2009|
|Last Updated Date||May 3, 2013|
|Start Date ICMJE||February 2006|
|Primary Completion Date||Not Provided|
|Current Primary Outcome Measures ICMJE||Not Provided|
|Original Primary Outcome Measures ICMJE||Not Provided|
|Change History||Complete list of historical versions of study NCT01036568 on ClinicalTrials.gov Archive Site|
|Current Secondary Outcome Measures ICMJE||Not Provided|
|Original Secondary Outcome Measures ICMJE||Not Provided|
|Current Other Outcome Measures ICMJE||Not Provided|
|Original Other Outcome Measures ICMJE||Not Provided|
|Brief Title ICMJE||Neuroimaging Studies of Neurophysiological Phenotypes in Schizophrenia|
|Official Title ICMJE||Neuroimaging Studies of Neurophysiological Phenotypes in Schizophrenia|
- Eye tracking, the ability to focus on and follow a moving target with the eyes, is often difficult for people who have schizophrenia. Research has shown that first-degree relatives of people with schizophrenia, such as parents and siblings, also tend to have difficulty with smooth eye movement and eye tracking. Researchers are interested in using functional magnetic resonance imaging (fMRI) to study brain activity during eye tracking tests in order to better understand the effect that schizophrenia has on brain function.
- To study eye-tracking and eye-tracking impairments in people with and without schizophrenia.
- Individuals between 18 and 62 years of age in one of three groups: (1) patients who have been diagnosed with schizophrenia/schizoaffective disorder, (2) first-degree relatives of patients in group 1, and (3) healthy volunteers with no family history of psychosis.
The proposed protocol aims to combine functional magnetic resonance imaging (fMRI) and SPEM eyetracking measures to study 1) the neural circuit controlling the psychophysical, cognitive, and oculomotor aspects of eyetracking; 2) the underlying neural mechanism of schizophrenia-related eyetracking impairments; and 3) the degree to which pursuit-related imaging changes aggregate in families. The human eye movement system is complex. It is likely that only components of the system, rather than the whole system, are involved in the pathology of schizophrenia.
Three groups of subjects will be tested: schizophrenic patients (approximately n=60), full siblings of patients (approximately n=60), and healthy controls without family history of psychosis (approximately n=60). To reach this goal of 60 per group we expect to enroll 225 subjects.
Experiments in this protocol employ fMRI in combination with psychophysical and oculomotor paradigms to dissect the neural correlates of the neurophysiological components controlling pursuit eye movement. A high-resolution in-magnet eyetracking system will be used during imaging. Using this imaging technology we will be able to associate behavioral performance with specific brain regions.
Combining fMRI and visual neuroscience techniques, this protocol will study the functional neuroanatomic underpinnings of smooth pursuit eye movement (SPEM) deficits in schizophrenia. We aim to establish a pathophysiological model of the illness based on the SPEM paradigm. Such a disease model may provide safe in vivo examination of the effects of pharmacological interventions, comorbidity, and functionality relating to schizophrenia. For example, patients with schizophrenia have high comorbidity of nicotine use. High incidence of substance abuse in schizophrenia suggests that the two conditions may share some common pathophysiology. Excessive nicotine use in schizophrenia is increasingly viewed as a form of self-medication by patients to correct underlying pathophysiological changes caused by the illness. We have found that nicotine can transiently improve smooth pursuit eye movement deficits in patients. We are currently examining the nicotinic effect on the learning components of smooth pursuit eye movement in schizophrenic patients using fMRI. This is an example on how carefully validated behavioral/imaging paradigm can be used as a pathophysiological model in aiding the study of complex brain illness including schizophrenia and substance abuse. Clearly, this research direction also requires a parallel research effort that aims at in-depth understanding of the foundational neural mechanism of the smooth pursuit eye movement itself.
|Study Type ICMJE||Observational|
|Study Design ICMJE||Not Provided|
|Target Follow-Up Duration||Not Provided|
|Sampling Method||Not Provided|
|Study Population||Not Provided|
|Intervention ICMJE||Not Provided|
|Study Group/Cohort (s)||Not Provided|
* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
|Recruitment Status ICMJE||Completed|
|Estimated Enrollment ICMJE||225|
|Completion Date||March 2013|
|Primary Completion Date||Not Provided|
|Eligibility Criteria ICMJE||
Relatives of patients:
1. must be first degree relatives (full sibling, parent, or offspring)
First Degree Relatives of patients:
|Ages||18 Years to 62 Years|
|Accepts Healthy Volunteers||Yes|
|Contacts ICMJE||Contact information is only displayed when the study is recruiting subjects|
|Location Countries ICMJE||United States|
|NCT Number ICMJE||NCT01036568|
|Other Study ID Numbers ICMJE||999906405, 06-DA-N405|
|Has Data Monitoring Committee||Not Provided|
|Responsible Party||Not Provided|
|Study Sponsor ICMJE||National Institute on Drug Abuse (NIDA)|
|Collaborators ICMJE||Not Provided|
|Information Provided By||National Institutes of Health Clinical Center (CC)|
|Verification Date||March 2013|
ICMJE Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP