Role of the Brain in Processing Visually Presented Objects

NCT00357695 | Completed

• 2 other identifiers: 04004704-N-0047
• Study Type: observational
• Target: 45
• Locations: 1 country
• Sites: 1

Brief Summary

This study will examine the parts of the brain that use visual information to perform movements. Patients with certain brain lesions tend to have difficulty in processing visually presented objects. This study will look at the brain mechanisms underlying the visuo-motor integration. Healthy normal volunteers between 20 and 60 years of age are eligible for this study. People who have had a severe head injury with loss of consciousness or any other mental or neurological disorder diagnosed by a doctor may not participate. Candidates will be screened with a medical history, a physical examination focusing on finger movements, and a questionnaire. Participants' brain activity will be recorded using two techniques - magnetoencephalography(MEG) and magnetic resonance imaging (MRI) - while they watch pictures of various objects flashed on a screen. MEG is a procedure to record magnetic field changes produced by brain activity. During the recording, the subject sits comfortably in an armchair in a dimly lit room and watches pictures presented on a screen. About 50 pictures are shown per session. There are about five sessions, separated by 3-minute breaks. Functional MRI involves taking pictures of the brain using MRI while the subject performs a task. MRI uses a strong magnetic field and radio waves to obtain images of body organs and tissues. The MRI scanner is a metal cylinder surrounded by a magnetic field. The subject lies still on a table that can slide in and out of the scanner. During the scan, he or she looks at pictures in six test blocks of 1 minute each, with 30-second breaks between blocks.

Conditions

Healthy; Motor Skills

Keywords

Praxis; Grasping; Premotor Cortex; Visuo-Motor Integration; Motor Imagination

Eligibility Criteria

• Age: 20 Years - 60 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may not qualify if:

• A previous history of neurological diseases will be carefully taken by direct interview by the Principal or Associate Investigators. Subjects who had a head injury (severe enough to cause loss of consciousness) or other brain diseases causing mental disturbance, sensory impairment, or motor dysfunction in the past will be excluded. Subjects who have metals either in the mouth, such as dental prostheses, or in the head, such as surgical clips from any previous surgical procedures, are also excluded due to technical limitations in terms of MEG. Furthermore, subjects wearing glasses for visual correction and those with poor vision, even with contact lenses, are excluded also due to technical limitations for MEG. Subjects who have pacemakers or other implanted electrical devices, brain stimulators, dental implants, aneurysm clips (metal clips on the wall of a large artery), metallic prostheses (including metal pins and rods, heart valves, and cochlear implants), permanent eyeliner, implanted delivery pump, or shrapnel fragments, and welders and metal workers are excluded for MRI for the sake of safety of subjects. Finally, by doing a brief neurological examination of finger movements, the subjects with poor performance of fine finger movements or those who are judged to have mirror movements will be excluded.

Sponsors & Collaborators

• National Institute of Neurological Disorders and Stroke (NINDS): lead

Study Sites (1)

National Institutes of Health Clinical Center, 9000 Rockville Pike

Bethesda, Maryland, 20892, United States

Location

Related Publications (3)

• Jeannerod M, Arbib MA, Rizzolatti G, Sakata H. Grasping objects: the cortical mechanisms of visuomotor transformation. Trends Neurosci. 1995 Jul;18(7):314-20.

  PMID: 7571012 BACKGROUND

• Chan JL, Ross ED. Alien hand syndrome: influence of neglect on the clinical presentation of frontal and callosal variants. Cortex. 1997 Jun;33(2):287-99. doi: 10.1016/s0010-9452(08)70005-4.

  PMID: 9220259 BACKGROUND

• Jeannerod M, Decety J, Michel F. Impairment of grasping movements following a bilateral posterior parietal lesion. Neuropsychologia. 1994 Apr;32(4):369-80. doi: 10.1016/0028-3932(94)90084-1.

  PMID: 8047246 BACKGROUND

Study Design

• Study Type: observational
• Sponsor Type: NIH

Study Record Dates

• First Submitted: July 26, 2006
• First Posted: July 27, 2006
• Study Start: November 18, 2003
• Study Completion: October 28, 2008
• Last Updated: July 2, 2017

Record last verified: 2008-10-28

Locations

US (1)