Ignite Creation Date:
2024-05-05 @ 11:32 AM
Last Modification Date:
2024-10-26 @ 9:09 AM
Study NCT ID:
NCT00076700
Status:
COMPLETED
Last Update Posted:
2008-03-04
First Post:
2004-01-31
Brief Title:
Enhanced Tactile Memory in the Blind
Sponsor:
National Institute of Neurological Disorders and Stroke NINDS
Organization:
National Institutes of Health Clinical Center CC
Study Overview
Official Title:
Enhanced Tactile Memory in the Blind
Status:
COMPLETED
Status Verified Date:
2006-01
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:
This study will determine if the brain regions in blind people that would normally be involved in vision are used instead to remember touch Blind people have an enhanced sense of touch compared to sighted people and they also perform better on tests for certain kinds of memory This study will examine and compare the results of a touch memory test in blind and sighted people to determine what brain areas are involved in responding to touch
Blind people and sighted volunteers between 18 and 80 years of age who have no psychiatric problems or neurological problems other than blindness may be eligible for this study Candidates are screened with a medical interview and examination
Participants undergo one or both of the following procedures
Behavioral experiment
Sighted participants are blindfolded during this experiment Subjects sit comfortably in front of a table They are presented with a number of surfaces placed on a table one at a time and are given 10 seconds to feel each surface with the index finger on their dominant hand They must concentrate and memorize the surfaces as best they can After a 15-minute break they are again presented with a series of surfaces and given 10 seconds to feel each one This time they must say as quickly as possibly whether the surface is one they touched previously or is a new surface
Functional MRI
MRI uses a strong magnetic field and radio waves to obtain images of body organs and tissues In this study subjects undergo MRI scanning of the brain while performing the same touch test described above For the MRI the subject lies on a table that slides into the scanner The MRI machine detects change in the brain regions involved in performing the task
Blind people and sighted volunteers between 18 and 80 years of age who have no psychiatric problems or neurological problems other than blindness may be eligible for this study Candidates are screened with a medical interview and examination
Participants undergo one or both of the following procedures
Behavioral experiment
Sighted participants are blindfolded during this experiment Subjects sit comfortably in front of a table They are presented with a number of surfaces placed on a table one at a time and are given 10 seconds to feel each surface with the index finger on their dominant hand They must concentrate and memorize the surfaces as best they can After a 15-minute break they are again presented with a series of surfaces and given 10 seconds to feel each one This time they must say as quickly as possibly whether the surface is one they touched previously or is a new surface
Functional MRI
MRI uses a strong magnetic field and radio waves to obtain images of body organs and tissues In this study subjects undergo MRI scanning of the brain while performing the same touch test described above For the MRI the subject lies on a table that slides into the scanner The MRI machine detects change in the brain regions involved in performing the task
Detailed Description:
In the blind areas of the brain that would normally respond to visual stimuli instead of process information from other sensory modalities such as the somatosensory and auditory domains Recent studies have shown that the visual cortex of the blind participates in higher-order processing of auditory information including verb generation and retrieval of verbal memories Because tactile information plays a similarly crucial role when vision is missing ie to read Braille it has been suggested that the ability to encode and recall tactile information in the blind is superior to that in the sighted
OBJECTIVES
The first objective of this protocol is to determine if tactile memory is superior in early blind subjects relative to that in late blind and sighted control subjects
The second objective is to determine if the visual cortex of blind people can participate in higher-order processing of tactile information such as tactile encoding recognition
STUDY POPULATION
Our experiments will make use of early blind late blind and sighted control subjects
DESIGN
Experiment 1 We will quantify the ability of our study populations to encode into and retrieve from episodic tactile memory Subjects will be presented with a series of surfaces that they are to palpate and commit to memory after which they will rest for ten to fifteen minutes The old surfaces will then be presented again with a same number of new surfaces randomly interleaved Subjects are to discriminate old from new surfaces
Experiment 2 We will identify cortical areas associated with successful tactile memory encoding and retrieval in blind individuals and sighted controls using functional magnetic resonance imaging fMRI Subjects will perform the memory task from Experiment 1 while in the MRI machine
OUTCOME MEASURES
Experiment 1 The primary outcome measure will be recognition memory a corrected measure of the number of old stimuli correctly remembered
Experiment 2 The primary outcome measure will be the number of voxels significantly activated in primary visual cortex in early blind subjects as compared to late blind subjects and sighted controls
We expect the magnitude of visual cortex activation in the early blind during a tactile memory task to correlate with superior performance on the task
OBJECTIVES
The first objective of this protocol is to determine if tactile memory is superior in early blind subjects relative to that in late blind and sighted control subjects
The second objective is to determine if the visual cortex of blind people can participate in higher-order processing of tactile information such as tactile encoding recognition
STUDY POPULATION
Our experiments will make use of early blind late blind and sighted control subjects
DESIGN
Experiment 1 We will quantify the ability of our study populations to encode into and retrieve from episodic tactile memory Subjects will be presented with a series of surfaces that they are to palpate and commit to memory after which they will rest for ten to fifteen minutes The old surfaces will then be presented again with a same number of new surfaces randomly interleaved Subjects are to discriminate old from new surfaces
Experiment 2 We will identify cortical areas associated with successful tactile memory encoding and retrieval in blind individuals and sighted controls using functional magnetic resonance imaging fMRI Subjects will perform the memory task from Experiment 1 while in the MRI machine
OUTCOME MEASURES
Experiment 1 The primary outcome measure will be recognition memory a corrected measure of the number of old stimuli correctly remembered
Experiment 2 The primary outcome measure will be the number of voxels significantly activated in primary visual cortex in early blind subjects as compared to late blind subjects and sighted controls
We expect the magnitude of visual cortex activation in the early blind during a tactile memory task to correlate with superior performance on the task
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 |
|---|---|---|---|
| 04-N-0110 | None | None | None |