The main objective is to demonstrate the activation of the efferent inhibitory cortico-olivocochlear pathway with otoacoustic emission of the ear contralateral to the side of stimulation with TMS. We expect the amplitude to decrease after TMS of the…
ID
Source
Brief title
Condition
- Inner ear and VIIIth cranial nerve disorders
Synonym
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
The amplitude of the otoacoustic emission of the ear contralateral to the side
of the stimulation.
Secondary outcome
The secondary endpoint will be the difference in amplitude reduction of the
OAEs with respect to the different frequencies compared to placebo.
Background summary
Until recently only the medial olivocochlear efferent pathway in humans could
be demonstrated. But now the existence of an auditory corticofugal pathway in
humans has been demonstrated with direct electrical stimulation of the auditory
pathway by an implanted cortical electrode. The electrical stimulation of the
auditory cortex with the implanted electrode resulted in reduction of the
otoacoustic emissions (OAEs), sounds that are produced by the cochlea itself.
Reduction of OAEs by stimulation of the efferent auditory pathway gives a new
insight in the inhibitory qualities of the central auditory system. Potentially
Transcranial Magnetic Stimulation (TMS), a form of indirect electrical
stimulation of the cortex, can give this reduction in OAE as well. This can
have great implications for research of the central auditory system and the
therapeutic use of TMS.
Study objective
The main objective is to demonstrate the activation of the efferent inhibitory
cortico-olivocochlear pathway with otoacoustic emission of the ear
contralateral to the side of stimulation with TMS. We expect the amplitude to
decrease after TMS of the auditory cortex. The secondary objective is to
determine if the reduction in amplitude of the OAEs depends on the different
frequency used for TMS stimulation.
Study design
This study is an exploratory placebo-controlled intervention study with a
cross-over design.
Study burden and risks
The risk associated with TMS is a potential epileptic seizure. This risk is not
to be expected with the stimulation parameters used in this study and in
accordance with international safety guidelines for TMS.
Participation requires a total of 4 visits, with a total of 4 hours.
Hanzeplein 1
9700 RB Groningen
NL
Hanzeplein 1
9700 RB Groningen
NL
Listed location countries
Age
Inclusion criteria
Participated successfully in mentioned MRI studies
Presence of click-evoked OAEs in both ears
No otologic medical history
> 18 years of age
Exclusion criteria
•Presence of any major medical, neurological or psychiatric diagnoses now or in the past, specific epilepsy, severe head injury, increased intracranial pressure or previous cranial neurosurgery
•Metal parts inside the subject*s head (except in the mouth) or elsewhere in the body
•Cardiac pacemaker and/or implanted medication pump and/or intercardiac lines
•Use of drugs or medications that reduce cortical excitation such as anticonvulsants, benzodiazepines or other sedatives (e.g. antihistamines)
•Use of drugs or medications that reduces the seizure threshold, such as tricyclic anti-depressants and antipsychotic drugs.
•Pregnancy
Design
Recruitment
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
No registrations found.
In other registers
| Register | ID |
|---|---|
| CCMO | NL21863.042.08 |