Clinical trial NCT05018117: Effects of Nicotine and Attention on Frequency Tuning in Auditory Cortex
Official title: Effects of Nicotine and Attention on Frequency Tuning in Auditory Cortex
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: EARLY_PHASE1
Conditions: Aging
Keywords: nicotine
acetylcholine
functional magnetic resonance imaging
Lead sponsor: University of California, Berkeley
Sponsor class: OTHER
Collaborators: name: National Institute on Aging (NIA)
First posted: 2021-08-24
Enrollment: 48
Sex: ALL
Minimum age (years): 18
Maximum age (years): 85
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Intervention model description: Nicotine (6 mg, polacrilex gum) and placebo will be administered to each participant in separate sessions in a within-subject double-blind randomized crossover design. Subjects will be in either a young (18-28 years) or old (60-85 years) group.
Primary purpose: BASIC_SCIENCE

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.


Eligibility 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

Primary outcomes:
measure: frequency tuning of excitatory auditory fMRI cortical responses
timeFrame: Functional MRI recordings will begin approximately 30 minutes after oral administration of polacrilex or placebo gum and will continue for up to two hours.
Secondary outcomes:
measure: frequency tuning of inhibitory auditory fMRI cortical responses
timeFrame: Functional MRI recordings will begin approximately 30 minutes after oral administration of polacrilex or placebo gum and will continue for up to two hours.
measure: amplitude of excitatory auditory fMRI cortical responses
timeFrame: Functional MRI recordings will begin approximately 30 minutes after oral administration of polacrilex or placebo gum and will continue for up to two hours.
measure: amplitude of inhibitory auditory fMRI cortical responses
timeFrame: Functional MRI recordings will begin approximately 30 minutes after oral administration of polacrilex or placebo gum and will continue for up to two hours.
Other outcomes:
Locations:
city: Berkeley
country: United States
facility: University of California, Berkeley
state: California
Study officials:
affiliation: University of California, Berkeley
name: Michael A Silver, PhD
role: PRINCIPAL_INVESTIGATOR
References: