Effects of Nicotine and Attention on Frequency Tuning in Auditory Cortex
Study Details
Study Description
Brief Summary
Nicotine enhances auditory-cognitive function because it mimics the brain's system for "paying attention" to important sounds amid distractions (for example, understanding speech in a noisy environment). In part, nicotine does this by activating inhibitory neurons in the auditory cortex. Since age-related hearing deficits result, in part, from the loss of inhibitory neurons in auditory cortex, this project will determine whether nicotine's effects can compensate for reduced inhibition in the aging auditory cortex and thereby restore auditory function.
The investigators will use functional magnetic resonance imaging (fMRI) to measure the selectivity of responses in auditory cortex to tones of various frequencies. The investigators will measure the effects of nicotine (administered as chewing gum) and aging on these fMRI response properties. The investigators hypothesize that frequency selectivity will decrease with aging and increase following nicotine administration.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
Early Phase 1 |
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Experimental: Young (18-28 years) participants - nicotine gum 6 mg nicotine gum, one time before fMRI measurements |
Drug: Nicotine gum
The effects of over-the-counter nicotine gum will be compared to a placebo gum
Other Names:
|
| Experimental: Old (60-85 years) participants - nicotine gum 6 mg nicotine gum, one time before fMRI measurements |
Drug: Nicotine gum
The effects of over-the-counter nicotine gum will be compared to a placebo gum
Other Names:
|
| Placebo Comparator: Young (18-28 years) participants - placebo gum placebo gum, one time before fMRI measurements |
Other: Placebo gum
The effects of over-the-counter nicotine gum will be compared to a placebo gum
|
| Placebo Comparator: Old (60-85 years) participants - placebo gum placebo gum, one time before fMRI measurements |
Other: Placebo gum
The effects of over-the-counter nicotine gum will be compared to a placebo gum
|
Outcome Measures
Primary Outcome Measures
- frequency tuning of excitatory auditory fMRI cortical responses [Functional MRI recordings will begin approximately 30 minutes after oral administration of polacrilex or placebo gum and will continue for up to two hours.]
Functional magnetic resonance imaging (fMRI) responses to pure tone stimuli ranging from 88-8000 Hz will be recorded. For each voxel in objectively identified auditory cortical area, a tuning curve model will be fit to the data. One of the parameters of this model is the width of frequency tuning of excitatory responses, and this is the primary outcome measure.
Secondary Outcome Measures
- frequency tuning of inhibitory auditory fMRI cortical responses [Functional MRI recordings will begin approximately 30 minutes after oral administration of polacrilex or placebo gum and will continue for up to two hours.]
Functional magnetic resonance imaging (fMRI) responses to pure tone stimuli ranging from 88-8000 Hz will be recorded. For each voxel in objectively identified auditory cortical area, a tuning curve model will be fit to the data. One of the parameters of this model is the width of frequency tuning of inhibitory responses, and this is Outcome 2.
- amplitude of excitatory auditory fMRI cortical responses [Functional MRI recordings will begin approximately 30 minutes after oral administration of polacrilex or placebo gum and will continue for up to two hours.]
Functional magnetic resonance imaging (fMRI) responses to pure tone stimuli ranging from 88-8000 Hz will be recorded. For each voxel in objectively identified auditory cortical area, a tuning curve model will be fit to the data. One of the parameters of this model is the amplitude of excitatory responses, and this is Outcome 3.
- amplitude of inhibitory auditory fMRI cortical responses [Functional MRI recordings will begin approximately 30 minutes after oral administration of polacrilex or placebo gum and will continue for up to two hours.]
Functional magnetic resonance imaging (fMRI) responses to pure tone stimuli ranging from 88-8000 Hz will be recorded. For each voxel in objectively identified auditory cortical area, a tuning curve model will be fit to the data. One of the parameters of this model is the amplitude of inhibitory responses, and this is Outcome 4.
Eligibility Criteria
Criteria
Inclusion Criteria:
- non-smokers with a score of 0-2 out of 10 maximum on the Fagerström index of smoking dependency
Exclusion Criteria:
-
deafness or excessive hearing loss
-
smokers with a score between 3 and 10 on the Fagerström index of smoking dependency
-
history of psychiatric illness, neurological disorders, diabetes mellitus, renal failure, or cardiovascular disease
-
regular use of prescription medications (excluding oral contraceptives)
-
drug dependency
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | University of California, Berkeley | Berkeley | California | United States | 94720 |
Sponsors and Collaborators
- University of California, Berkeley
- National Institute on Aging (NIA)
Investigators
- Principal Investigator: Michael A Silver, PhD, University of California, Berkeley
Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- 2018-12-11682
- R01AG067073-01A1