2008 / 2007 ATA-Funded Research

New ATA-Funded Research
2008 / 2007 ATA-Funded Research
Past ATA-Funded Research

July 2008

Birgit Mazurek, M.D., Ph.D., Charité University Hospital, Berlin, Germany
Research Project: Molecular Basis of Salicylate-Induced Tinnitus
Roadmap Path: B
Funded: 1 year, $39,624

"Scientists widely recognize that tinnitus results from miscommunication between cells in the auditory system. We hypothesize that this incorrect communication reflects an abnormal gene expression. This means that perhaps the auditory cells of tinnitus sufferers produce too many or too few of the proteins important in auditory communication. This ATA grant enables us to do further analyses on expression of 18 genes involved in communication and function of the auditory system. We will perform these experiments on normal-hearing rats and rats with aspirin-induced tinnitus. We trust that the outcome of our work will uncover new therapeutic targets for tinnitus treatment."

Jennifer Melcher, Ph.D., Massachusetts Eye and Ear Infirmary,
Boston, Massachusetts
Research Project: Neurophysiology of Hyperacusis
Roadmap Path: A
Funded: 1 year, $50,000

"Many people with tinnitus find certain sounds unbearably loud, even though the same sounds may not be bothersome at all to other people. This condition is called hyperacusis. Using a type of brain imaging called functional Magnetic Resonance Imaging (fMRI), we showed that hearing centers in the brain are more active than normal in people with hyperacusis. Each hearing center contains many different types of brain cells. In our current research, we will test for over-activity by a particular subset of cells using techniques (EEG and MEG) that are sensitive to various aspects of brain activity. If the culprit cells can be identified, it may be possible to design ways to restore normal function, for instance, using drugs or electrical stimulation."

Athanasios Tzounopoulos, Ph.D., University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
Research Project: Cellular Mechanisms of Tinnitus
Roadmap Path: B
Funded: 1 year, $75,000

"Neuronal connections and neuronal activity can change as a result of ongoing experience. This is known as plasticity of the brain. This plasticity can lead to changes in memory or learning, compensation for loss of function and adaptation to changing demands. However, plasticity-induced changes can also cause signs and symptoms of disease. Tinnitus – commonly referred to as ringing in the ears or head – is the perception of sound in the absence of an environmental acoustic stimulus. Recent studies have shown that individuals with tinnitus have increased neuronal activity in certain areas of the brain. We hypothesize that the same cellular mechanisms responsible for mediating plasticity in these areas may also underlie tinnitus. Determining these mechanisms will point to specific drug treatments that may reduce or alleviate tinnitus."

Fan-Gang Zeng, Ph.D., University of California, Irvine, California
Research Project: Tinnitus Suppression
Roadmap Paths: C, D
Funded: 1 year of 2-year project, $88,006

"One misperception is that, except for masking tinnitus, for instance with music, tinnitus does not interact with external sounds. In our opinion, this misperception has severely limited our options in treating and potentially curing tinnitus. Different from masking, which typically requires a masker to have higher intensity and similar pitch to the tinnitus, tinnitus suppression can occur with sounds that are softer and potentially more pleasant than the tinnitus. The novel aspect of our research is to understand interaction between tinnitus and external sounds, using acoustic and electrical stimulation, with a particular focus on searching for external sounds that can effectively suppress tinnitus."

January 2008

Shaowen Bao, Ph.D., University of California, Berkeley, California
Research Project: Cortical Plasticity in Tinnitus
Roadmap Path: B, C
Funded: 1 year, $99,949

"Recent studies have revealed substantial changes in brain activity patterns in tinnitus patients and in animals with hearing loss. These brain activity changes, known as cortical plasticity, potentially produce hearing loss-induced tinnitus. It is still unclear, however, whether cortical plasticity actually causes tinnitus. In the lab, we will induce cortical plasticity that is similar to that seen in tinnitus patients, only without any accompanying hearing loss. If the plasticity induces tinnitus, then it is not just a side-effect of hearing loss."

Paul Finlayson, Ph.D., Wayne State University, Detroit, Michigan
Research Project: Tinnitus and Hyperactivity in the Dorsal Cochlear Nucleus Fusiform Cells: Biophysical Changes
Roadmap Path: B
Funded: 1 year of 2-year project, $49,954

"The most common form of tinnitus develops after noise-induced trauma. Multiple changes in the brain occur following trauma due to intense sound exposure, including loss of cells, changes in the function of individual cells and in the communication between cells. This research will study the cellular changes affecting brain cell hyperactivity in the dorsal cochlear nucleus, which directly receives input from the auditory nerve. We will examine the movement of the ions that control the electrical activity in the cells. Determining how cells change, how their communication changes and why they become hyperactive is central to defining how these changes produce tinnitus and also help in developing possible tinnitus treatments."

William Martin, Ph.D., Oregon Hearing Research Center, Oregon Health & Science University, Portland, Oregon
Research Project: Clinical Trial of Acamprosate for Tinnitus
Roadmap Path: C
Funded: 3 years, $73,829

"Acamprosate is a medication used to treat brain chemical imbalances that lead to alcohol addiction. This clinical trial will evaluate acamprosate to see if it can provide significant tinnitus relief for a subgroup of tinnitus patients. The study will further determine if there are patient-related factors (e.g., degree of hearing loss, duration of their tinnitus, depression, anxiety or insomnia) that we can use to predict whether or not acamprosate will be helpful for a specific patient. It will also help increase our understanding of the brain's role in tinnitus and improve future designs of new, effective treatments."

Kelvin M. Kwong, Wayne State University, Detroit, Michigan
Student Grant
Research Project: Mechanisms Underlying Acoustic Masking of Tinnitus
Roadmap Path: A, B
Funded: 1 year, $10,000

"Masking is commonly used to provide relief to tinnitus sufferers. Masking involves covering up the tinnitus with another sound. However, we do not yet sufficiently understand the process. The goal of this project is to determine the neural mechanisms underlying the relief of tinnitus from acoustic masking. We will measure activity in parts of the brain known to correlate with tinnitus perception. We will examine this brain activity before, during and after acoustic masking stimulation to determine if masking plays a role in changing tinnitus-related neural activity."

Daniel Stolzberg, State University of New York, Buffalo, New York
Student Grant
Research Project: Ensemble Spontaneous Activity in Tinnitus
Roadmap Path: A
Funded: 1 year, $10,000

"Modern theories of tinnitus point to the hearing areas of the brain as the generator of this phantom sound. Neurons are the cells of the brain which are in constant, rhythmic communication with one another. In tinnitus, neurons in hearing areas of the brain may lose this normal rhythm, generating a persistent miscommunication which emerges as a phantom sound. Additionally, anesthesia changes how neurons normally communicate. To address that problem, this project will utilize animals that are awake (not anesthetized) to investigate the changes in communication between both individual neurons and groups of neurons, and to determine why these communication changes generate tinnitus."

Pim Van Dijk, Ph.D., University of Groningen, Groningen, the Netherlands
Research Project: Response of the Central Auditory System in Tinnitus and Hearing Loss, an fMRI Study
Roadmap Path: A
Funded: 1 year of 2-year project, $99,100

"Every sound we hear, including tinnitus, is related to some pattern of brain activity. Abnormal neural brain activity is the likely cause of tinnitus. This project will investigate brain patterns using functional magnetic resonance imaging (fMRI). An fMRI takes pictures of a brain’s activity, much as a video camera takes pictures of a body’s activity. We will compare hearing impaired patients with and without tinnitus to determine why some hearing impaired patients have tinnitus while others do not. We expect this to help clarify which brain activity patterns are specific to tinnitus."

July 2007

Richard Altschuler, Ph.D., University of Michigan, Ann Arbor, Michigan
Research Project: Tinnitus Associated Changes in Excitatory Synaptic Strength and Intrinsic Properties in the Rat DCN
Roadmap Path: A
Funded: 1 year, $99,917

"Increased nerve activity in the hearing regions of the brain appears to cause central tinnitus (tinnitus generated by the central nervous system). Inhibitory chemicals normally prevent this rise in activity. Evidence demonstrates that a decrease in these chemicals causes a rise in nerve activity. Our study will examine whether glutamate, a chemical that increases (excites) brain activity, also plays a role. We will test whether the presence of persistent tinnitus changes the inherent properties of the ion channels that regulate nerve activity. If our research shows that changes in glutamate or ion channels are associated with central tinnitus, it will open the avenue to new methods of intervention for the treatment of tinnitus."

Dirk De Ridder, M.D., Ph.D., University Hospital, Antwerp, Belgium
Research Project: A Method for Measuring Tinnitus and Tinnitus Intensity Objectively: an fMRI-EEG Study
Roadmap Path: A
Funded: 1 year, $96,668

"Our research will help develop objective diagnostic tests for tinnitus that are affordable, simple and quick. When a stimulus, such as a sound, becomes consciously perceived, brain waves oscillate at frequencies around 40 Hz. This is also called gamma band activity. This activity is present only during stimulation; when a sound wanes, so does the activity. If someone constantly perceives tinnitus, gamma band activity should be constantly present in the auditory cortex. Also, the louder the tinnitus, the more gamma band activity there might be. Using an electroencephalogram (EEG), we will look for gamma band measurements that objectively illustrate tinnitus presence and loudness. A second part of the study will look at brain activity using a functional magnetic resonance imaging (fMRI) machine, and try to correlate fMRI images to tinnitus presence and intensity. If we are able to objectively measure tinnitus, then we can use these same principles and technology to investigate tinnitus distress."

Didier A. Depireux, Ph.D., University of Maryland School of Medicine, Baltimore, Maryland
Research Project: Targeting the Changes in Inferior Colliculus Induced by Tinnitus
Roadmap Path: A, C
Funded: 1 year, $50,000

"There is a strong correlation between tinnitus and altered neural activity in the inferior colliculus, a brain structure essential for sound perception. This makes the inferior colliculus a natural place to measure the effect that various tinnitus treatments might have. In a novel approach, we will measure neural activity in the inferior colliculus of animals before and after noise-induced trauma. We will also measure the changes in how an animal brain processes complex sounds such as speech and music before and after noise trauma. Lidocaine (a local anesthetic) can alleviate tinnitus, but it has serious side effects. We will perform the above experiments with intravenous Lidocaine to better understand its effect. This will provide important clues about why Lidocaine reduces tinnitus, and will help determine other pharmaceuticals that might similarly quiet tinnitus but with fewer side effects."

Edward Lobarinas, Ph.D., State University of New York at Buffalo, Buffalo, New York
Research Project: Brain Imaging of Salicylate and Noise-Induced Tinnitus in Rats
Roadmap Path: A
Funded: $168,579

"Why do some people develop tinnitus while others exposed to the same conditions do not? Studies in humans have shown that brain activity in patients with tinnitus differs from the activity of patients who do not experience tinnitus. However, in these studies, scientists cannot control the event that started the tinnitus or look at how the tinnitus developed and changed over time. Research using animal models can control conditions, such as exposure to loud noise, that are often associated with the onset of tinnitus. We use these models to study how tinnitus develops and what conditions maintain it. This study will combine animal models of tinnitus with brain imaging. The goal is to understand how tinnitus starts and which areas of the brain change as tinnitus develops after exposure to loud noise or treatment with drugs known to generate tinnitus. We will evaluate brain activity in animals that show behavioral evidence of tinnitus using a brain scanner known as MicroPET. We hope to use this advanced imaging technology to study tinnitus and lay a foundation for advanced diagnosis and a potential method of evaluating effective tinnitus treatment strategies."

January 2007

Nicola Schutte, Ph.D., University of New England, New South Wales, Australia
Research Project: The Effectiveness of Bibliotherapy for Alleviating Tinnitus
Roadmap Path: D
Funded: 1 year, 39,859

"Establish if a cognitive behavioral therapy (CBT) self-help book helps alleviate tinnitus distress and elucidate the relationship between emotional functioning and tinnitus acceptance."

Michael Brian Calford, Ph.D., School of Biomedical Sciences, University of Newcastle, Australia
Research Project: Neuroplasticity, Behavior and Therapeutic Training in an Animal Model of Tinnitus
Roadmap Path: B, C
Funded: 1 year, $96,740

"The cochlea, a spiral-shaped part of the inner ear, processes sound by transforming it from physical vibrations (like the bass rhythm one might feel at a concert) into “electrochemical” signals that the brain interprets as sound. These vibrations activate different neurons (cells) in the ear depending on the frequency of the incoming sound. High frequency sounds vibrate the outside of the cochlea’s spiral; low frequencies vibrate the inside. This pattern of neural stimulation repeats throughout the hearing pathways of the brain. This means that different cells in the brain respond to different frequencies, just like ear cells do."

Donald M. Caspary, Ph.D., Southern Illinois University School of Medicine, Springfield, Illinois
Research Project: The Glycine Receptor in a Rat Tinnitus Model: A Possible Therapeutic Target
Roadmap Path: B
Funded: 1 year, $99,780

"One theory about what causes tinnitus is that the loss of normal sound input due to hearing loss leads to changes in the brain. These brain changes frequently involve a loss of normal inhibitory activity. This means that when hearing is lost, some brain chemical circuits malfunction. These circuits normally adjust the way that certain brain cells respond to sound. So when these inhibitory circuits malfunction, other nerve cells may show increased activity, known as hyperactivity. When this hyperactivity occurs, normal background sounds in the brain may become audible. Tinnitus researchers today are focusing their attention on this nerve cell hyperactivity as a likely cause of tinnitus generation."