Breaking News
December 16, 2018 - ‘Easy Way Out’? Stigma May Keep Many From Weight Loss Surgery
December 16, 2018 - Gout drug may protect against chronic kidney disease
December 16, 2018 - Talking about memories enhances the wellbeing of older and younger people
December 16, 2018 - Occupational exposure to pesticides increases risk for cardiovascular disease among Latinos
December 16, 2018 - A biomarker in the brain’s circulation system may be Alzheimer’s earliest warning
December 16, 2018 - Magnesium may play important role in optimizing vitamin D levels, study shows
December 16, 2018 - The effect of probiotics on intestinal flora of premature babies
December 16, 2018 - Parents spend more time talking with kids about mechanics of using mobile devices
December 16, 2018 - Biohaven Announces Positive Results from Ongoing Rimegepant Long-Term Safety Study
December 16, 2018 - Arterial stiffness may predict dementia risk
December 16, 2018 - Study explores link between work stress and increased cancer risk
December 16, 2018 - Sex work criminalization linked to incidences of violence finds study
December 16, 2018 - Johns Hopkins researchers discover swarming behavior in fish-dwelling parasite
December 16, 2018 - Schistosomiasis prevention and treatment could help control HIV
December 16, 2018 - Early postpartum opioids linked with persistent usage
December 16, 2018 - Johns Hopkins researchers identify molecular causes of necrotizing enterocolitis in preemies
December 16, 2018 - Advanced illumination expands capabilities of light-sheet microscopy
December 16, 2018 - Alzheimer’s could possibly be spread via contaminated neurosurgery
December 16, 2018 - Unraveling the complexity of cancer biology can prompt new avenues for drug development
December 16, 2018 - Inflammatory Bowel Disease, Prostate Cancer Linked
December 16, 2018 - Cannabis youth prevention strategy should target mental wellbeing
December 15, 2018 - Recent developments and challenges in hMAT inhibitors
December 15, 2018 - Sewage bacteria found lurking in Hudson River sediments
December 15, 2018 - CDC selects UMass Amherst biostatistician model that helps predict influenza outbreaks
December 15, 2018 - Researchers reveal brain mechanism that drives itch-evoked scratching behavior
December 15, 2018 - New computer model helps predict course of the disease in prostate cancer patients
December 15, 2018 - Obesity to Blame for Almost 1 in 25 Cancers Worldwide
December 15, 2018 - How the brain tells you to scratch that itch
December 15, 2018 - New findings could help develop new immunotherapies against cancer
December 15, 2018 - World’s largest AI-powered medical research network launched by OWKIN
December 15, 2018 - Young people suffering chronic pain battle isolation and stigma as they struggle to forge their identities
December 15, 2018 - Lifespan extension at low temperatures depends on individual’s genes, study shows
December 15, 2018 - New ingestible capsule can be controlled using Bluetooth wireless technology
December 15, 2018 - Researchers uncover microRNAs involved in the control of social behavior
December 15, 2018 - Research offers hope for patients with serious bone marrow cancer
December 15, 2018 - Link between poverty and obesity is only about 30 years old, study shows
December 15, 2018 - Mass spectrometry throws light on old case of intentional heavy metal poisoning
December 15, 2018 - BeyondSpring Announces Phase 3 Study 105 of its Lead Asset Plinabulin for Chemotherapy-Induced Neutropenia Meets Primary Endpoint at Interim Analysis
December 15, 2018 - Study finds that in treating obesity, one size does not fit all
December 15, 2018 - Tenacity and flexibility help maintain psychological well-being, mobility in older people
December 15, 2018 - Study reveals role of brain mechanism in memory recall
December 15, 2018 - High levels of oxygen encourage the brain to remain in deep, restorative sleep
December 15, 2018 - Experimental HIV vaccine strategy works in non-human primates, research shows
December 15, 2018 - Genetically modified pigs could limit replication of classical swine fever virus, study shows
December 15, 2018 - FDA Approves Herzuma (trastuzumab-pkrb), a Biosimilar to Herceptin
December 15, 2018 - Cost and weight-loss potential matter most to bariatric surgery patients
December 15, 2018 - Cancer Research UK and AstraZeneca open new Functional Genomics Centre
December 15, 2018 - New research lays out potential path for treatment of Huntington’s disease
December 15, 2018 - Prestigious R&D 100 Award presented to Leica Microsystems
December 15, 2018 - Study shows septin proteins detect and kill gut pathogen, Shigella
December 15, 2018 - Study sheds new light on disease-spreading mosquitoes
December 15, 2018 - 2017 Saw Slowing in National Health Care Spending
December 15, 2018 - Monitoring movement reflects efficacy of mandibular splint
December 15, 2018 - Study supports BMI as useful tool for assessing obesity and health
December 15, 2018 - Self-guided, internet-based therapy platforms effectively reduce depression
December 15, 2018 - Organically farmed food has bigger climate impact than conventional food production
December 15, 2018 - Faster, cheaper test has potential to enhance prostate cancer evaluation
December 15, 2018 - Researchers study abnormal blood glucose levels of patients after hospital discharge
December 15, 2018 - Swedish scientists explore direct association of dementia and ischemic stroke deaths
December 15, 2018 - Study finds 117% increase in number of dementia sufferers in 26 years
December 15, 2018 - Eczema Can Drive People to Thoughts of Suicide: Study
December 15, 2018 - Link between neonatal vitamin D deficiency and schizophrenia confirmed
December 15, 2018 - Nurse denied life insurance because she carries naloxone
December 15, 2018 - Ritalin drug affects organization of pathways that build brain networks used in attention, learning
December 15, 2018 - Research pinpoints two proteins involved in creation of stem cells
December 15, 2018 - Gut bacteria may modify effectiveness of anti-diabetes drugs
December 15, 2018 - A new type of ‘painless’ adhesive for biomedical applications
December 15, 2018 - Early physical therapy associated with reduction in opioid use
December 15, 2018 - Breast cancer protection from pregnancy begins many decades later, study finds
December 15, 2018 - How often pregnant women follow food avoidance strategy to prevent allergy in offspring?
December 15, 2018 - Using machine learning to predict risk of developing life-threatening infections
December 15, 2018 - How imaginary friends could boost children’s development
December 15, 2018 - Folate deficiency creates more damaging chromosomal abnormalities than previously known
December 15, 2018 - Study provides new insights into molecular mechanisms underlying role of amyloid in Alzheimer’s disease
December 15, 2018 - For the asking, a check is in the mail to help pay for costly drugs
December 15, 2018 - UA scientists uncover biological processes leading to rare brain disorder in babies
December 15, 2018 - The largest database on industrial poisons
December 15, 2018 - ESMO Immuno-Oncology Congress showcases novel technologies set to benefit many cancer patients
December 15, 2018 - Ovid Therapeutics Announces Plans to Move into a Phase 3 Trial in Pediatric Patients Based on End-of-Phase 2 Meeting for OV101 in Angelman Syndrome
December 15, 2018 - Left ventricular noncompaction – Genetics Home Reference
Experimental device could help ease tinnitus symptoms by targeting unruly nerve activity in the brain

Experimental device could help ease tinnitus symptoms by targeting unruly nerve activity in the brain

image_pdfDownload PDFimage_print

Millions of Americans hear ringing in their ears — a condition called tinnitus — but a new study shows an experimental device could help quiet the phantom sounds by targeting unruly nerve activity in the brain.

In a new paper in Science Translational Medicine, a team from the University of Michigan reports the results of the first animal tests and clinical trial of the approach, including data from 20 human tinnitus patients.

Based on years of scientific research into the root causes of the condition, the device uses precisely timed sounds and weak electrical pulses that activate touch-sensitive nerves, both aimed at steering damaged nerve cells back to normal activity.

Human participants reported that after four weeks of daily use of the device, the loudness of phantom sounds decreased, and their tinnitus-related quality of life improved. A sham “treatment” using just sounds did not produce such effects.

Results from tests in guinea pigs and the double-blind human study funded by the Coulter Foundation validate years of pre-clinical research funded by the National Institutes of Health, including previous tests in guinea pigs.

The U-M team has new NIH funding for an additional clinical trial to further refine the approach. U-M holds a patent on the concept behind the device and is developing it for potential commercialization.

“The brain, and specifically the region of the brainstem called the dorsal cochlear nucleus, is the root of tinnitus,” says Susan Shore, Ph.D., the U-M Medical School professor who leads the research team. “When the main neurons in this region, called fusiform cells, become hyperactive and synchronize with one another, the phantom signal is transmitted into other centers where perception occurs.

“If we can stop these signals, we can stop tinnitus,” she continues. “That is what our approach attempts to do, and we’re encouraged by these initial parallel results in animals and humans.”

A dual-stimulus approach to treating tinnitus

The approach, called targeted bimodal auditory-somatosensory stimulation, involves two senses.

The device plays a sound into the ears, alternating it with precisely timed, mild electrical pulses delivered to the cheek or neck.

This sets off a process called stimulus-timing dependent plasticity, or STDP, which was first explored in animals and led to long-term changes in the rate at which the nerves fire. The approach aims to re-set the activity of fusiform cells, which normally help our brains receive and process both sounds and sensations such as touch or vibration – what scientists call somatosensory inputs.

Under normal conditions, fusiform cells help our brains focus on where sounds are coming from, and help us tune out sensations that result from the movement of our own head and neck.

But the U-M team’s previous work in animals showed that loud noise can trigger a change in the nerve cells’ activity – altering its timing so that they fire off synchronized signals spontaneously instead of waiting for an actual sound in the environment.

The toll of tinnitus

These events in animals parallel what happens in humans. After exposure to such things as loud noises, head or neck trauma, or other triggering events, some people develop a persistent sensation that they’re hearing sounds like ringing or a grinding noise.

Approximately 15 percent of Americans have some level of tinnitus, but the worst symptoms occur in about 10 percent of sufferers, according to estimates based on interviews with nationally representative samples of Americans. Many of those with more severe tinnitus also have hearing loss.

Some cases are severe. As many as two million people can’t work or carry out other daily activities because of the tinnitus itself, or the psychological distress it causes them. Tinnitus is the most common cause of service-connected disability among veterans of the U.S. military.

Current approaches to tinnitus treatment focus include efforts to address the psychological distress it causes, for instance through cognitive behavioral therapy. Other approaches use sound to mask the phantom sounds or attempt to modulate the brain response. For more severe cases, some patients turn to invasive, and therefore riskier, approaches such as deep brain stimulation and vagal nerve stimulation. The current approach provides a novel and unique, non-invasive strategy that aims to modulate and correct the aberrant neural pathways that cause tinnitus.

Study details

Shore and her colleagues are based in U-M’s Kresge Hearing Research Institute, which is part of the Department of Otolaryngology at Michigan Medicine, U-M’s academic medical center. Co-first authors Kendra Marks, Au.D., David Martel, M.S.E. and Calvin Wu, Ph.D., are all members of the Shore laboratory.

They recruited a particular kind of tinnitus sufferer for their study: those who can temporarily alter their symptoms if they clench their jaws, stick out their tongues, or turn or flex their necks.

These maneuvers, Shore says, appear to be self-discovered ways of changing the activity of fusiform cells – providing an external somatosensory signal to modulate their tinnitus.

The U-M device delivers sounds matched to the loudness and pitch of the phantom sounds that each patient hears. It also delivers mild electrical impulses applied to the area of the head involved in the patients’ own tinnitus-altering maneuvers.

The crucial timing of the auditory and electrical stimulation came directly from tests in guinea pigs that had noise-induced tinnitus, reported in the new paper. Those tests showed that specific timing between delivery of the two kinds of stimuli was necessary to suppress the hyperactive fusiform cells.

After patients had the device calibrated to their own tinnitus symptoms, they learned to apply its earphones and electrodes for a 30-minute session each day. Half the group received the bimodal sound-and-electricity treatment for the first four weeks, while the other half received just sounds. Then, they all took a four-week break, and started the next four weeks receiving the opposite of what they’d received before. None of them knew which option they got first.

Every week, the patients took a survey about how much their tinnitus was affecting their lives, and a test of how loud their tinnitus sounds were.

Results in human participants

Overall, the loudness of phantom sounds decreased only after the actual, or bimodal, treatment, but not the sham treatment of sound only. For some the decrease was around 12 decibels, about the magnitude of an electric lightbulb’s hum. Two participants said their tinnitus disappeared completely.

The quality of life survey – where a low score indicates less impact from tinnitus – is called TFI, and is measured on a 100-point scale. Statistical modeling of the results revealed that, on average, patients experienced significantly reduced scores for the active treatment, though the size of the effect in individual patients varied. On average, scores also stayed lower for weeks after treatment ended. This effect was not significant for the sham treatment.

No patient experienced a worsening of symptoms or quality of life, or other adverse events. Some said their phantom sounds got less harsh or piercing, or became easier to ignore.

“We’re definitely encouraged by these results, but we need to optimize the length of treatments, identify which subgroups of patients may benefit most, and determine if this approach works in patients who have non-somatic forms of the condition that can’t be modulated by head and neck maneuvers,” says Shore.

Source:

http://www.ns.umich.edu/new/multimedia/videos/25353-specially-timed-signals-ease-tinnitus-symptoms-in-test-aimed-at-condition-s-root-cause

Tagged with:

About author

Related Articles