Ignite Creation Date:
2024-05-05 @ 11:24 AM
Last Modification Date:
2024-10-26 @ 9:06 AM
Study NCT ID:
NCT00024960
Status:
COMPLETED
Last Update Posted:
2017-07-02
First Post:
2001-10-09
Brief Title:
Dopamine Function in Developmental Stuttering
Sponsor:
National Institute on Deafness and Other Communication Disorders NIDCD
Organization:
National Institutes of Health Clinical Center CC
Study Overview
Official Title:
Assessment of Pre- and Post-Synaptic Dopamine Function in Developmental Stuttering Using 11C-Raclopride and Positron Emission Tomography
Status:
COMPLETED
Status Verified Date:
2010-10-29
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 use positron emission tomography PET to examine the role of the chemical messenger dopamine in stuttering It will measure and compare the number of dopamine receptors and the amount of dopamine released in the brains of stutterers with that of normal volunteers The results may provide information about how drugs that block dopamines effect might work to enable fluent speech
Healthy normal volunteers and people with developmental stuttering between the ages of 18 and 55 may be eligible for this study Candidates will be screened with a medical history and possibly a physical examination and laboratory tests
Participants will have a hearing test and cognitive function tests to measure speech language memory and visual skills In addition they will undergo the following procedures
PET scanning to measure brain blood flow and dopamine distribution in the brain PET uses radioactive materials to show cellular activity in specific tissues of the body Before starting the procedure a thin plastic tube intravenous or IV line is placed in a vein in each arm of the subject and a special plastic mask is molded to the face The mask is used to insure that the position of the head does not change during the scan For the scan the subject lies on a bed that is positioned into the scanner A preliminary transmission scan is done to make necessary measurements and adjustments Following this scan 10 injections of radioactive water are given through an IV line During these injections the subject performs a series of speech tasks-such as singing telling a story or reciting nursery rhymes-that will elicit either fluent speech or stuttering A special camera detects the radiation emitted and produces images of brain blood flow during stuttering and normal speech Next raclopride a radioactive material that attaches to dopamine receptors on the cell surface is given through an IV line and more pictures of the brain are taken Fifty minutes after the raclopride injection amphetamine-a drug that increases brain dopamine levels-is injected through the other IV line and more pictures are taken to show dopamine distribution in the brain Fifty minutes after the amphetamine infusion the IV lines are removed
Magnetic resonance imaging MRI of the brain to complement and interpret information from the PET scans MRI uses a strong magnetic field and radio waves to show structural changes in tissues The subject lies on a table surrounded by a metal cylinder the scanner During the procedure which may take from 20 minutes to 2 hours subjects may be asked to perform simple tasks such as speaking or moving their arms They can speak with a staff member via an intercom at all times during the procedure and can be moved out of the machine any time they request
Participants may be asked to return for up to two scanning sessions within a year For these scans only 1 injection of radioactive water will be given
Healthy normal volunteers and people with developmental stuttering between the ages of 18 and 55 may be eligible for this study Candidates will be screened with a medical history and possibly a physical examination and laboratory tests
Participants will have a hearing test and cognitive function tests to measure speech language memory and visual skills In addition they will undergo the following procedures
PET scanning to measure brain blood flow and dopamine distribution in the brain PET uses radioactive materials to show cellular activity in specific tissues of the body Before starting the procedure a thin plastic tube intravenous or IV line is placed in a vein in each arm of the subject and a special plastic mask is molded to the face The mask is used to insure that the position of the head does not change during the scan For the scan the subject lies on a bed that is positioned into the scanner A preliminary transmission scan is done to make necessary measurements and adjustments Following this scan 10 injections of radioactive water are given through an IV line During these injections the subject performs a series of speech tasks-such as singing telling a story or reciting nursery rhymes-that will elicit either fluent speech or stuttering A special camera detects the radiation emitted and produces images of brain blood flow during stuttering and normal speech Next raclopride a radioactive material that attaches to dopamine receptors on the cell surface is given through an IV line and more pictures of the brain are taken Fifty minutes after the raclopride injection amphetamine-a drug that increases brain dopamine levels-is injected through the other IV line and more pictures are taken to show dopamine distribution in the brain Fifty minutes after the amphetamine infusion the IV lines are removed
Magnetic resonance imaging MRI of the brain to complement and interpret information from the PET scans MRI uses a strong magnetic field and radio waves to show structural changes in tissues The subject lies on a table surrounded by a metal cylinder the scanner During the procedure which may take from 20 minutes to 2 hours subjects may be asked to perform simple tasks such as speaking or moving their arms They can speak with a staff member via an intercom at all times during the procedure and can be moved out of the machine any time they request
Participants may be asked to return for up to two scanning sessions within a year For these scans only 1 injection of radioactive water will be given
Detailed Description:
Clinical responses to dopamine DA antagonists from patients with developmental stuttering suggest that the pathophysiology of this disorder may involve an abnormality of central DA systems This hypothesis has never been tested using methods that measure both pre- and postsynaptic dopaminergic mechanisms within the CNS A new PET technique permits evaluation of these mechanisms in human subjects 11C raclopride a relatively selective D2 receptor antagonist is used to estimate postsynaptic DA receptor binding potential following establishment of equilibrium conditions A low dose bolus of amphetamine is then used to release DA from the presynaptic neuron and displace the ligand from postsynaptic binding sites in order to estimate the size of the releasable presynaptic DA pool We propose to use this technique in individuals with developmental stuttering and control subjects to test the hypothesis that stuttering is due to dopaminergic hyperactivity within the CNS The cause of this hyperactivity is hypothesized to be due to an increase in either the postsynaptic binding potential or the size of the releasable presynaptic dopamine vesicular pool in which case postsynaptic receptors may be down regulated Our studies should help conjoin and modify this pathophysiological model If low dose amphetamine can be used to demonstrate a difference between people who stutter and controls a second study will be conducted to see if stuttering behavior per se has a measurable effect on DA release that differs from the effect of similar speech tasks in control subjects Lastly in a third study DA releasability will be measured in those recovered from stuttering and those not affected by stuttering but are part of families who have many members that stutter The culmination of these studies is to attempt isolation of a DA marker that can be used as a phenotyping tool in genetic studies of stuttering
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 |
|---|---|---|---|
| 02-DC-0008 | None | None | None |