Ignite Creation Date:
2024-05-05 @ 7:42 PM
Last Modification Date:
2024-10-26 @ 9:53 AM
Study NCT ID:
NCT00726050
Status:
COMPLETED
Last Update Posted:
2017-07-02
First Post:
2008-07-30
Brief Title:
Brain Activity in Time Discrimination and Sensory Input
Sponsor:
National Institute of Neurological Disorders and Stroke NINDS
Organization:
National Institutes of Health Clinical Center CC
Study Overview
Official Title:
The Relationship Between Temporal Discrimination and Cortical Excitability in Humans
Status:
COMPLETED
Status Verified Date:
2010-04-29
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 repetitive transcranial magnetic stimulation or rTMS magnetic stimulation to the brain to examine how the brain distinguishes between two signals that are spaced very closely in time The ability to tell the difference between sensory signals is important to understanding sensory input Understanding how this works may help to develop new treatments for sensory deficits
Healthy volunteers 18 years of age and older may be eligible for this study Participants undergo the following procedures during three visits to the NIH Clinical Center
rTMS - all visits sham rTMS on one visit
For TMS a wire coil is held on the scalp A brief electrical current passed through the coil creates a magnetic pulse that stimulates the brain During the stimulation the subject may be asked to tense certain muscles slightly or perform other simple actions
Theta burst stimulation TBS - all visits sham TBS on one visit
Same as TMS but brief pulses of electrical current are passed through the coil Subjects undergo intermittent TBS on one visit and continuous TBS on another
Somatosensory evoked potential SEP - all visits
SEP tests how sensory information travels along the nerves to the spinal cord and brain A small metal disk electrode placed on an arm delivers a small electrical shock Electrodes placed on the scalp record how the impulse travels over the nerve pathways to the cerebral cortex of the brain EEG see below records what sensory information the brain is detecting and processing Paired-pulse SEP is done before and after TBS
Temporal discrimination threshold - all visits
This test investigates the brains ability to discriminate sensory information Electrodes are placed on the subjects wrist Two electrical pulses are delivered to the nerve at the wrist at different spaced intervals to determine when the subject feels the two pulses are fused into one This test is done before and after TBS
Electroencephalography EEG - all visits
This test records brain waves electrical activity of the brain Electrodes are placed on the scalp with an electrode cap The spaces between the electrodes and the scalp are filled with a gel that conducts electrical activity
Healthy volunteers 18 years of age and older may be eligible for this study Participants undergo the following procedures during three visits to the NIH Clinical Center
rTMS - all visits sham rTMS on one visit
For TMS a wire coil is held on the scalp A brief electrical current passed through the coil creates a magnetic pulse that stimulates the brain During the stimulation the subject may be asked to tense certain muscles slightly or perform other simple actions
Theta burst stimulation TBS - all visits sham TBS on one visit
Same as TMS but brief pulses of electrical current are passed through the coil Subjects undergo intermittent TBS on one visit and continuous TBS on another
Somatosensory evoked potential SEP - all visits
SEP tests how sensory information travels along the nerves to the spinal cord and brain A small metal disk electrode placed on an arm delivers a small electrical shock Electrodes placed on the scalp record how the impulse travels over the nerve pathways to the cerebral cortex of the brain EEG see below records what sensory information the brain is detecting and processing Paired-pulse SEP is done before and after TBS
Temporal discrimination threshold - all visits
This test investigates the brains ability to discriminate sensory information Electrodes are placed on the subjects wrist Two electrical pulses are delivered to the nerve at the wrist at different spaced intervals to determine when the subject feels the two pulses are fused into one This test is done before and after TBS
Electroencephalography EEG - all visits
This test records brain waves electrical activity of the brain Electrodes are placed on the scalp with an electrode cap The spaces between the electrodes and the scalp are filled with a gel that conducts electrical activity
Detailed Description:
Objective
The ability to discriminate successive signals separated by time intervals in the millisecond-range is an important element in analyzing the temporal characteristics of sensory input When two identical stimuli are presented with a sufficient time interval between them they are readily perceived as being two separate events As they are presented progressively closer together there comes a point when the two separate stimuli are perceived as one However the neural mechanism of temporal discrimination is unclear Therefore our major objective is to analyze in detail the effect of cortical excitability and inhibition on temporal sensory discrimination in healthy subjects
Study Population
We intend to study 25 adult healthy volunteers
Design
Assuming the cortical circuit in the somatosensory area plays an important role in temporal discrimination we plan to investigate the relationship between cortical excitability and the ability of temporal discrimination We hypothesize that the extent of cortical excitability affects the ability to discriminate Cortical excitability will be modulated by using repetitive transcranial magnetic stimulation rTMS Comparison of cortical excitability changes will be determined before and after rTMS in the primary somatosensory cortex SI The change in cortical information processing in SI will be studied using multi-channel electroencephalography EEG recording of paired-pulse somatosensory evoked potentials SEPs delivered at rest Activity assessment in the cortical circuit will be measured by the recovery curve of the amplitude of paired-pulse SEPs
Outcome Measures
The primary outcome measure will be the change in amplitude of the paired-pulse SEP component P27 in 5-ms interstimulus interval condition for three types of rTMS The secondary outcome will be the amplitude of paired-pulse SEP components during other interstimulus interval conditions 10 to 200 ms
The ability to discriminate successive signals separated by time intervals in the millisecond-range is an important element in analyzing the temporal characteristics of sensory input When two identical stimuli are presented with a sufficient time interval between them they are readily perceived as being two separate events As they are presented progressively closer together there comes a point when the two separate stimuli are perceived as one However the neural mechanism of temporal discrimination is unclear Therefore our major objective is to analyze in detail the effect of cortical excitability and inhibition on temporal sensory discrimination in healthy subjects
Study Population
We intend to study 25 adult healthy volunteers
Design
Assuming the cortical circuit in the somatosensory area plays an important role in temporal discrimination we plan to investigate the relationship between cortical excitability and the ability of temporal discrimination We hypothesize that the extent of cortical excitability affects the ability to discriminate Cortical excitability will be modulated by using repetitive transcranial magnetic stimulation rTMS Comparison of cortical excitability changes will be determined before and after rTMS in the primary somatosensory cortex SI The change in cortical information processing in SI will be studied using multi-channel electroencephalography EEG recording of paired-pulse somatosensory evoked potentials SEPs delivered at rest Activity assessment in the cortical circuit will be measured by the recovery curve of the amplitude of paired-pulse SEPs
Outcome Measures
The primary outcome measure will be the change in amplitude of the paired-pulse SEP component P27 in 5-ms interstimulus interval condition for three types of rTMS The secondary outcome will be the amplitude of paired-pulse SEP components during other interstimulus interval conditions 10 to 200 ms
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 |
|---|---|---|---|
| 08-N-0189 | None | None | None |