Ignite Creation Date:
2024-05-05 @ 11:21 AM
Last Modification Date:
2024-10-26 @ 9:05 AM
Study NCT ID:
NCT00006285
Status:
COMPLETED
Last Update Posted:
2017-07-02
First Post:
2000-09-16
Brief Title:
Use of Transcranial Magnetic Stimulation TMS and Magnetic Resonance Imaging MRI to Study Visual Attention
Sponsor:
National Institute of Mental Health NIMH
Organization:
National Institutes of Health Clinical Center CC
Study Overview
Official Title:
Transcranial Magnetic Stimulation Studies of Visual Attention
Status:
COMPLETED
Status Verified Date:
2009-06-08
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
The purpose of this study is to learn more about how the brain allows people to focus on important objects and filter out unimportant ones when looking at visual images
Our senses provide us with a vast amount of information at any given moment in time For example visual scenes contain many different objects that cannot be processed simultaneously because of the limited processing capacity of the brains visual system Evidence suggests that a a network of brain regions selects relevant information and filters out irrelevant information when people view cluttered visual scenes This study will use transcranial magnetic stimulation TMS and functional magnetic resonance imaging fMRI to determine how the different brain regions involved in attentional control and filtering interact
Participants in this study will undergo computer tests an MRI scan and TMS During the MRI participants will look at pictures and count objects appearing on a screen During the TMS participants will perform a computer test Participants ability to pay attention will be tested with and without TMS Participants may be asked to return for additional tests in the future
Our senses provide us with a vast amount of information at any given moment in time For example visual scenes contain many different objects that cannot be processed simultaneously because of the limited processing capacity of the brains visual system Evidence suggests that a a network of brain regions selects relevant information and filters out irrelevant information when people view cluttered visual scenes This study will use transcranial magnetic stimulation TMS and functional magnetic resonance imaging fMRI to determine how the different brain regions involved in attentional control and filtering interact
Participants in this study will undergo computer tests an MRI scan and TMS During the MRI participants will look at pictures and count objects appearing on a screen During the TMS participants will perform a computer test Participants ability to pay attention will be tested with and without TMS Participants may be asked to return for additional tests in the future
Detailed Description:
Our senses provide us with a vast amount of information at any given moment in time For example visual scenes contain many different objects that cannot all be processed simultaneously because of the limited processing capacity of the visual system Therefore attentional mechanisms are required to select relevant objects and filter out irrelevant ones There is converging evidence from single-cell recording and lesion studies in monkeys and functional brain imaging studies in humans that irrelevant information from cluttered visual scenes is filtered out in extrastriate visual cortex Functional brain imaging studies also suggest that these attentional filtering mechanisms are mediated by top-down feedback signals arising in higher-order areas in frontal and parietal cortex However it is not clear from these studies whether these frontal and parietal brain regions are functionally significant in attentional control of behavior
Transcranial magnetic stimulation TMS applied over a particular cortical region can interfere with cognitive processing in that region thereby creating a virtual disruption in the intact human cerebral cortex Hence this tool can be used to determine if a brain region is functionally involved in the performance of a given cognitive function In the proposed study we wish to use TMS to test the hypothesis that attentional filter mechanisms operating in extrastriate cortex are under top-down control by regions in the frontal and parietal cortex Our approach will use a combination of TMS and functional magnetic resonance imaging fMRI
First subjects will participate in an fMRI experiment 93-M-0170 designed to localize the cortical regions of interest ROIs that are involved with attentional processing for each subject Second TMS will be used to create transient virtual disruptions in frontal and parietal ROIs of normal volunteers while they perform a task requiring spatial attention We hypothesize that when TMS is used to interfere with attentional processing subjects will show impaired performance in a task that requires them to filter out irrelevant visual information In contrast performance during TMS should not suffer in a control task in which no irrelevant information needs to be filtered out
Transcranial magnetic stimulation TMS applied over a particular cortical region can interfere with cognitive processing in that region thereby creating a virtual disruption in the intact human cerebral cortex Hence this tool can be used to determine if a brain region is functionally involved in the performance of a given cognitive function In the proposed study we wish to use TMS to test the hypothesis that attentional filter mechanisms operating in extrastriate cortex are under top-down control by regions in the frontal and parietal cortex Our approach will use a combination of TMS and functional magnetic resonance imaging fMRI
First subjects will participate in an fMRI experiment 93-M-0170 designed to localize the cortical regions of interest ROIs that are involved with attentional processing for each subject Second TMS will be used to create transient virtual disruptions in frontal and parietal ROIs of normal volunteers while they perform a task requiring spatial attention We hypothesize that when TMS is used to interfere with attentional processing subjects will show impaired performance in a task that requires them to filter out irrelevant visual information In contrast performance during TMS should not suffer in a control task in which no irrelevant information needs to be filtered out
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
None
Is a FDA Regulated Device?:
None
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None
Secondary IDs
| Secondary ID | Type | Domain | Link |
|---|---|---|---|
| 00-M-0177 | None | None | None |