Clinical Research Directory

Tizanidine and Acoustic Reflex

The goal of this clinical trial is to learn how the muscle relaxant tizanidine affects the acoustic reflex in adults. The acoustic reflex is a natural protection system of the ear that helps reduce the impact of loud sounds. It is not known whether tizanidine changes how this reflex works. The main question this study aims to answer is: Does taking tizanidine for 1 week change acoustic reflex thresholds in the same person, when comparing before and after treatment? Participants who receive tizanidine will undergo hearing and acoustic reflex tests before treatment and again at the end of the treatment period.

A Treatment for a Form of Age-Related Central Auditory Processing Disorder Consisting of Clemastine Fumarate Plus Engineered Sound

The goal of this clinical trial is to determine the efficacy of Clemastine Fumarate in the presence of engineered sound to treat age-related central auditory processing disorder (CAPD). This disorder impacts 800M patients worldwide, including \~1/3 people over 40 years of age and \~1/2 people over 65, resulting in an inability to hear in noisy environments. The primary hypothesis this study aims to test is: engineered sound, driving localized neural circuit activity, will enable Clemastine Fumarate to mature Oligodendrocyte cells and thus remyelinate these activated neural circuits. This Localized Oligodendrocyte Optimization Therapy (LOOT) was highly effective in preclinical animal studies so this clinical trial aims to answer if this therapy will translate to humans. The study is an adaptive design intended to compare the efficacy of the drug in the presence or absence of the engineered sound for improving hearing in noise ability. Trial participants will be tested for hearing thresholds and ability to isolate a sound signal from background noise. If they meet the inclusion criteria, they will be enrolled into one of the four arms of the study and undergo the proposed one-month treatment (drug and sound or respective placebos). After the treatment period, trial participants will be tested again for hearing thresholds and their ability to isolate s sound source of interest from background noise. The hypothesis to be tested in this clinical trial is that the one-month treatment will significantly improve the participant's ability to isolate a sound source of interest from background noise. The design has four arms, drug+sound, placebo+sound, drug+white noise, and placebo+white noise. Based on our preclinical data, control arms are all expected to show identical results, thus our adaptive design includes interim analyses to allow for dropping of two of the three placebo arms should the preclinical results be replicated as anticipated. We will also monitor each participant's general health during the duration of the clinical trial, which will be done by performing a number of blood tests, an EKG and a general physical before and after the one-month treatment period. We expect no significant changes since participants will take the drug for the one-month period at dosages already demonstrated safe in several Phase II studies of multiple sclerosis. Similarly, the engineered sound will be listened to for one hour per day during this month at sound intensities well below threshold that might cause noise-induced hearing damage.

Apple Health Study

The Apple Health Study aims to build a diverse and inclusive group of participants to help researchers advance our understanding of how signals and information collected from apps and devices relate to health and may be used to predict, detect, monitor, and manage changes in health. To enroll, US residents who have an iPhone can download the Apple Research app from the App Store and go through the introduction and informed consent for the Apple Health Study. This study is fully remote, and all are invited to enroll if the eligibility criteria are met. Participants will be asked to complete tasks and surveys, using their iPhone and Apple Research app which include: * Selecting the types of data they would like to share with the study such as health and sensor data * Completing tasks and surveys including areas such as personal demographic information, personal medical history, family history, and social determinants of health

Perception of Speech in Context by Listeners With Healthy and Impaired Hearing

Recognition of speech sounds is accomplished through the use of adjacent sounds in time, in what is termed acoustic context. The frequency and temporal properties of these contextual sounds play a large role in recognition of human speech. Historically, most research on both speech perception and sound perception in general examine sounds out-of-context, or presented individually. Further, these studies have been conducted independently of each other with little connection across labs, across sounds, etc. These approaches slow the progress in understanding how listeners with hearing difficulties use context to recognize speech and how their hearing aids and/or cochlear implants might be modified to improve their perception. This research has three main goals. First, the investigators predict that performance in speech sound recognition experiments will be related when testing the same speech frequencies or the same moments in time, but that performance will not be related in further comparisons across speech frequencies or at different moments in time. Second, the investigators predict that adding background noise will make this contextual speech perception more difficult, and that these difficulties will be more severe for listeners with hearing loss. Third, the investigators predict that cochlear implant users will also use surrounding sounds in their speech recognition, but with key differences than healthy-hearing listeners owing to the sound processing done by their implants. In tandem with these goals, the investigators will use computer models to simulate how neurons respond to speech sounds individually and when surrounded by other sounds.

Investigating the Effect of Caffeine Consumption on Speech Understanding in Noise in Young Adults

Caffeine is a widely consumed substance worldwide and is often used to increase alertness and improve cognitive functions. Caffeine stimulates brain activity by binding to adenosine receptors, which increases alertness instead of sleepiness. Studies on the effects of caffeine on cognitive functions have shown that it improves basic cognitive functions such as attention, reaction time, and alertness, while a less pronounced effect is seen on sensory functions such as vision and hearing. However, no study has been found investigating the effect of caffeine consumption on understanding speech in noise. Understanding speech in noise is a skill that includes not only auditory functions but also cognitive functions. This skill is affected by cognitive elements such as selective attention and executive functions. In this context, it is thought that this study, which aims to examine the relationship between caffeine and understanding speech in noise, will contribute to the literature. 60 participants between the ages of 18-30 will be included in this study. Participants will consist of individuals without hearing loss (SSO\<25 dB nHL), no history of neurological or psychological disorders, non-smokers, and those who do not use ototoxic drugs. Participants will be randomly divided into a placebo group that consumes decaffeinated coffee and a study group that consumes coffee containing 300 mg caffeine. The Turkish Matrix Test will be administered 30 minutes after coffee consumption. In addition, participants will be asked to keep a caffeine diary for one week to determine their daily caffeine consumption and will be asked to fill out the Caffeine Use Disorder Scale. Thus, they will be divided into low and high caffeine consumption groups and their speech understanding skills in noise will be compared.