CompletedNot Applicable

Attention and Visual Perception

United States8 participantsStarted 2005-05-16

Plain-language summary

The NIMH is conducting studies aimed at gaining a better understanding of the areas of the brain that are involved in different types of mental processes. This study will focus on brain regions involved in visual perception and attention. Healthy normal volunteers and people who have had a stroke or undergone neurosurgery may be eligible for this study. Candidates must be 18 years of age or older, They must not have a history of a psychiatric disorder, including depression, anxiety, psychosis, or neurological disease other than stroke or the previous neurosurgery. Participants undergo the following tests and procedures during four or more visits to the NIH Clinical Center: * Physical and neurological examinations and depression rating scale. * Cognitive testing: Subjects complete written tests, sit at a computer and make decisions about what they are shown by pressing keys, or answer questions from a test examiner. * Behavioral training: Subjects practice performing a cognitive task that involves looking at and making decisions about visual images that appear on a computer screen. * Magnetic resonance imaging (MRI): Subjects undergo MRI scanning while they perform the task they previously practiced. The MRI scanner is a metal cylinder surrounded by a strong magnetic field. During the procedure, subjects lie still for up to 10 minutes at a time on a table that can slide in and out of the cylinder. The entire MRI scanning session takes about one hour. There are multiple scans which each can take up to 10 minutes. They may be asked to return for one or two additional scanning sessions. During the behavioral training or MRI scanning, special pieces of equipment that monitor eye movements may be used. Some subjects may be asked to return to NIH for an additional visit to participate in a magnetoencephalographic scan. This test uses several sensors applied to the scalp to measure very small changes in magnetic fields. This is another way to measure brain activity.

Who can participate

Age range18 Years – 80 Years

SexALL

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AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

* INCLUSION CRITERIA: ALL SUBJECTS - All subjects will be volunteers and be 18 years of age or older. PATIENTS - Subjects with unilateral or bilateral lesions of prefrontal or parietal cortex will be selected for participation in the behavioral and brain-imaging studies described within this protocol. Control subjects with unilateral or bilateral lesions of temporal cortex will also be studied. Finally, patients with amygdala lesions will also be studied to test the specific hypothesis outlined in Experiment 4. In order to obtain a sufficient number of focal lesion patients representative of different brain regions, patients with different etiologies will be studied, provided the damage is circumscribed. The main etiologies that we will consider are stroke, lobectomy, and tumor. We will restrict groups to include patients with the same etiology, lesion location, and lesion volume. Lesion location will consider the two hemispheres separately. Patients who also have non-amygdala subcortical lesions will be grouped separately from patients with cortical-only lesions. Our goal is to not group patients with more focal brain lesions compromising a single region (e.g., middle frontal gyrus) with patients with more massive damage (e.g., large extents of superior, middle, and inferior frontal gyrus). Focal lesion patients will not be excluded on the basis of medication. NORMAL VOLUNTEERS - Neurologically normal, age-matched volunteers will be recruited from the local com…

Trial details

NCT IDNCT00111293

SponsorNational Institute of Mental Health (NIMH)

Sponsor typeNIH

Study typeOBSERVATIONAL