Tactile Spatial AcuityNCT00357058
Role of Brain Region Changes in Tactile (Touch) Ability Following Nerve Block
An observational study of Tactile Spatial Acuity and Healthy, run by National Institute of Neurological Disorders and Stroke (NINDS) at 1 site in United States.
Trial summary
This study will examine the role of different brain regions in tactile (touch) ability after application of a tourniquet (inflated blood pressure cuff). When the forearm is deprived of blood for a short period of time, tactile ability in the other hand improves. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Tactile Spatial Acuity, Healthy
- How many people
- 90 participants
- Where
- 1 siteUnited States
- Study dates
- 12 Dec 2001to 28 Dec 2007
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Normal volunteers who are willing and able to remain relaxed and immobile during active scans, for a period of up to 2 hours.
Who cannot join
- Subjects with: metal in the cranium except for crowns or fillings in mouth and permanent metal dental braces, metal fragments from occupational exposure or surgical clips in or near the brain.
- Subjects with eye, blood vessel, cochlear or eye implants, with increased intracranial pressure as evaluated by clinical means, with cardiac or neural pacemakers, intracardiac lines and/or implanted medication pumps.
- Subjects with large hemorrhagic or brain stem stroke.
- Subjects with multiple cerebral lesions with residual deficits.
- Subjects with history of head injury with loss of consciousness.
- Subjects with history of severe alcohol or drug abuse or psychiatric illness.
Show all 12Show fewer
- Subjects with unstable cardiac dysrhythmia or unresponsive arterial hypertension (greater than 160/100 mmHg).
- Subjects with history of hyperthyroidism or individuals receiving drugs acting primarily on the central nervous system or disorders of the blood coagulation system.
- Subjects with excessive callus at their fingers.
- Preganant women will be excluded from the study.
- SUBJECTS DISCONTINUATION CRITERIA:
- Subject's poor compliance with protocol evaluations or examinations and subject's request to withdraw.
Trial locations and contacts
1 site in 1 country.
United States1 site
National Institutes of Health Clinical Center, 9000 Rockville Pike
Bethesda, Maryland, 20892
About this study
Official title: Substrates Mediating Deafferentiation-Induced Enhancement of Tactile Spatial Acuity
This study will examine the role of different brain regions in tactile (touch) ability after application of a tourniquet (inflated blood pressure cuff). When the forearm is deprived of blood for a short period of time, tactile ability in the other hand improves. This study will try to learn what causes this improvement.
Healthy normal volunteers are eligible for this study. Candidates will have a brief medical history and physical examination.
Read more
Volunteers will undergo two experiments, described below, that involve the following procedures:
- Ischemic nerve block - A blood pressure cuff is inflated for 35-40 minutes around the elbow area (also around the calf for Experiment 2 - see below). The resulting numbness, tingling, loss of muscle strength, and discoloration of the forearm and hand disappear within minutes after the cuff is deflated.
- Magnetic resonance imaging (MRI) - This test uses a magnetic field and radio waves instead of X-rays to produce images of brain structure and function. The volunteer lies on a stretcher that is moved into the scanner (a cylinder containing a strong magnet), wearing earplugs to protect the ears from loud thumping noises that occur with electrical switching of radio frequency circuits. The subject can communicate with an investigator by intercom at all times during the scan.
- Transcranial magnetic stimulation (TMS) - An insulated wire coil is placed on the patient's scalp. A brief electrical current passes through the coil, creating a magnetic pulse that travels through the scalp and skull and causes small electrical currents in the outer part of the brain. The stimulation may cause muscle hand or arm twitching or transient tingling in the forearm, head or face muscles.
- Tactile spatial acuity testing - The subject's left arm is placed in a cast and the left index finger is immobilized for this test which involves identifying the direction of grooves applied to the finger.
Experiment 1
This experiment measures changes in tactile acuity and brain activation following cuff inflation. The subject lies in the MRI scanner, with the left arm immobilized. Tactile acuity is measured repetitively at the left index finger during placement and inflation of a pressure cuff around the right forearm. The experiment consists of two sessions with the cuff around the forearm and one with the cuff around the calf and lasts from 90 minutes to 2 hours.
Experiment 2
This experiment measures changes in tactile acuity linked to TMS stimulation. The subject sits in an armchair with the left arm immobilized. Tactile acuity is measured repetitively at the left index finger during placement and inflation of a pressure cuff around the right forearm. In addition, TMS pulses (about one pulse per second) are delivered at different locations over the right side of the head for up to 30 minutes. The experiment consists of 10 separate sessions on different days, each lasting about 1 hour.
Read the detailed description
Acute deafferentation in one hand leads to improvements in tactile discriminative skills in the other, non-deafferented hand. This phenomenon, recently identified in our laboratory, represents an adaptive, behaviorally important consequence of deafferentation. It demonstrates that acute loss of sensory input from one hand results in rapid improvement of skills in the remaining hand. The first experiment in this protocol seeks to identify cortical regions activated in association with this improvement in tactile spatial acuity. In the second experiment, we will determine the effects of transient inactivation of focal cortical regions on this behavioral gain. While the first experiment will characterize brain regions activated in association with this performance improvement, the second experiment will provide information on the functional role of these regions. Understanding the substrates that mediate this behavioral gain may be important for the design of strategies to enhance them.
- Conditions
- Tactile Spatial Acuity, Healthy
- Keywords
- Deafferentiation-Induced Plasticity, fMRI, Cortical Reorganization, Tactile Performance, Transcranial Magnetic Stimulation, Tactile Discrimination, Plasticity, Healthy Volunteer, HV, Normal Control
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted27 Jul 2006 (estimated)
- Study start12 Dec 2001
- Study completion28 Dec 2007
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Tactile Spatial AcuityStudies of the same condition, open and under way.
- More trials run by National Institute of Neurological Disorders and Stroke (NINDS)The sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Enrolment
- 90 participants
Sponsor and investigators
- Sponsor type
- US National Institutes of Health
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT00357058
- Sponsor's protocol ID
- 020079
- Other IDs
- 02-N-0079
- Status last verified
- 28 Dec 2007
- First submitted
- 26 Jul 2006
- Last updated
- 2 Jul 2017
- Results posted
- No
Publications
Allard T, Clark SA, Jenkins WM, Merzenich MM. Reorganization of somatosensory area 3b representations in adult owl monkeys after digital syndactyly. J Neurophysiol. 1991 Sep;66(3):1048-58. doi: 10.1152/jn.1991.66.3.1048.
PubMed 1753275
Study at a glance
From the registry record, last updated by the sponsor on 2 Jul 2017. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Substrates Mediating Deafferentiation-Induced Enhancement of Tactile Spatial Acuity
- ClinicalTrials.gov ID
- NCT00357058
- Acronym / sponsor ID
- 020079
- Conditions
- Tactile Spatial Acuity, Healthy
- Keywords
- Deafferentiation-Induced Plasticity, fMRI, Cortical Reorganization, Tactile Performance, Transcranial Magnetic Stimulation, Tactile Discrimination, Plasticity, Healthy Volunteer
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 90 participants
- Lead sponsor
- National Institute of Neurological Disorders and Stroke (NINDS)US National Institutes of Health
- Study start
- 12 Dec 2001
- Study completion
- 28 Dec 2007
- First posted
- 27 Jul 2006 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study will examine the role of different brain regions in tactile (touch) ability after application of a tourniquet (inflated blood pressure cuff). When the forearm is deprived of blood for a short period of time, tactile ability in the other hand improves. This study will try to learn what causes this improvement.
Healthy normal volunteers are eligible for this study. Candidates will have a brief medical history and physical examination.
Volunteers will undergo two experiments, described below, that involve the following procedures:
- Ischemic nerve block - A blood pressure cuff is inflated for 35-40 minutes around the elbow area (also around the calf for Experiment 2 - see below). The resulting numbness, tingling, loss of muscle strength, and discoloration of the forearm and hand disappear within minutes after the cuff is deflated.
- Magnetic resonance imaging (MRI) - This test uses a magnetic field and radio waves instead of X-rays to produce images of brain structure and function. The volunteer lies on a stretcher that is moved into the scanner (a cylinder containing a strong magnet), wearing earplugs to protect the ears from loud thumping noises that occur with electrical switching of radio frequency circuits. The subject can communicate with an investigator by intercom at all times during the scan.
- Transcranial magnetic stimulation (TMS) - An insulated wire coil is placed on the patient's scalp. A brief electrical current passes through the coil, creating a magnetic pulse that travels through the scalp and skull and causes small electrical currents in the outer part of the brain. The stimulation may cause muscle hand or arm twitching or transient tingling in the forearm, head or face muscles.
- Tactile spatial acuity testing - The subject's left arm is placed in a cast and the left index finger is immobilized for this test which involves identifying the direction of grooves applied to the finger.
Experiment 1
This experiment measures changes in tactile acuity and brain activation following cuff inflation. The subject lies in the MRI scanner, with the left arm immobilized. Tactile acuity is measured repetitively at the left index finger during placement and inflation of a pressure cuff around the right forearm. The experiment consists of two sessions with the cuff around the forearm and one with the cuff around the calf and lasts from 90 minutes to 2 hours.
Experiment 2
This experiment measures changes in tactile acuity linked to TMS stimulation. The subject sits in an armchair with the left arm immobilized. Tactile acuity is measured repetitively at the left index finger during placement and inflation of a pressure cuff around the right forearm. In addition, TMS pulses (about one pulse per second) are delivered at different locations over the right side of the head for up to 30 minutes. The experiment consists of 10 separate sessions on different days, each lasting about 1 hour.
Detailed description
Acute deafferentation in one hand leads to improvements in tactile discriminative skills in the other, non-deafferented hand. This phenomenon, recently identified in our laboratory, represents an adaptive, behaviorally important consequence of deafferentation. It demonstrates that acute loss of sensory input from one hand results in rapid improvement of skills in the remaining hand. The first experiment in this protocol seeks to identify cortical regions activated in association with this improvement in tactile spatial acuity. In the second experiment, we will determine the effects of transient inactivation of focal cortical regions on this behavioral gain. While the first experiment will characterize brain regions activated in association with this performance improvement, the second experiment will provide information on the functional role of these regions. Understanding the substrates that mediate this behavioral gain may be important for the design of strategies to enhance them.
Study design
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (1 listed)
- Normal volunteers who are willing and able to remain relaxed and immobile during active scans, for a period of up to 2 hours.
Key exclusion criteria (12 listed)
- Subjects with: metal in the cranium except for crowns or fillings in mouth and permanent metal dental braces, metal fragments from occupational exposure or surgical clips in or near the brain.
- Subjects with eye, blood vessel, cochlear or eye implants, with increased intracranial pressure as evaluated by clinical means, with cardiac or neural pacemakers, intracardiac lines and/or implanted medication pumps.
- Subjects with large hemorrhagic or brain stem stroke.
- Subjects with multiple cerebral lesions with residual deficits.
- Subjects with history of head injury with loss of consciousness.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Not reported in the source record.
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 2 Jul 2017.
- Background: PubMed 1753275Allard T, Clark SA, Jenkins WM, Merzenich MM. Reorganization of somatosensory area 3b representations in adult owl monkeys after digital syndactyly. J Neurophysiol. 1991 Sep;66(3):1048-58. doi: 10.1152/jn.1991.66.3.1048.
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Tactile Spatial Acuity and Healthy, run by National Institute of Neurological Disorders and Stroke (NINDS) at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 1 inclusion and 12 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 2 Jul 2017. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT00357058, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 2 Jul 2017.