Using DNA as a drug -- commonly called gene therapy -- in laboratory mice may protect the inner ear nerve cells of humans suffering from certain types of progressive hearing loss, researchers have discovered. While the research is in its early stages, it has the potential to lead to a cure for some varieties of deafness.
Following are a selection of interesting news items from our field. This section will be updated on a continuous basis so check back often in between issues, to see what is new.
People with balance disorders or dizziness traceable to an inner-ear disturbance show distinctive abnormal eye movements when the affected ear is exposed to the strong pull of an MRI’s magnetic field, researchers have found, expanding on earlier research. Two new studies now suggest that these strong magnets could be used to diagnose, treat and study inner ear disorders in the future, replacing more invasive and uncomfortable examinations.
While probing how organisms sense gravity and acceleration, scientists uncovered evidence that acid (proton concentration) plays a key role in communication between neurons. Scientists discovered that sensory cells in the inner ear continuously transmit information on orientation of the head relative to gravity and low-frequency motion to the brain using protons as the key means of synaptic signal transmission.
As people approach old age, they generally become less outgoing. New research from the University of Gothenburg shows that this change in personality is amplified among people with impaired hearing. The findings emphasise the importance of acknowledging and treating hearing loss in the elderly population.
The researchers studied 400 individuals 80-98 years old over a six-year period. Every two years, the subjects were assessed in terms of physical and mental measures as well as personality aspects such as extraversion, which reflects the inclination to be outgoing, and emotional stability. The results show that even if the emotional stability remained constant over the period, the participants became less outgoing.
Interestingly, the researchers were not able to connect the observed changes to physical and cognitive impairments or to age-related difficulties finding social activities. The only factor that could be linked to reduced extraversion was hearing loss.
‘To our knowledge, this is the first time a link between hearing and personality changes has been established in longitudinal studies. Surprisingly, we did not find that declining overall health and functional capacity make people less outgoing. But hearing loss directly affects the quality of social situations. If the perceived quality of social interaction goes down, it may eventually affect whether and how we relate to others,’ says Anne Ingeborg Berg, PhD, licensed psychologist and researcher at the Department of Psychology, University of Gothenburg.
The study yields interesting knowledge about personality development late in life, and also points to the importance of acknowledging and treating hearing loss among the elderly.
The utilisation of hearing aids did not affect the correlation found, which suggests that there is a need for support in the use of aids such as hearing devices.
‘Our previous studies have shown that outgoing individuals are happier with their lives. It is hypothesised that an outgoing personality reflects a positive approach to life, but it also probably shows how important it is for most people to share both joy and sadness with others. Even if we can’t conclude anything about causal relationships, we can guess that the link between hearing loss and social withdrawal forms a potential threat to older people’s wellbeing,’ says Berg.
Elephants can discern human languages and distinguish human genders by listening to voices, according to a study in the Proceedings of the National Academy of Sciences. Scientists link elephants' hearing with their capacity for memory. "Basically they have developed this very rich knowledge of the humans that they share their habitat with. Memory is key. They must build up that knowledge somehow," said Karen McComb, author of the study and an animal behavior and cognition professor at the University of Sussex.
Multiple regions in the human genome are reported to be linked to musical aptitude, according to a new study. The function of the candidate genes implicated in the study ranges from inner-ear development to auditory neurocognitive processes, suggesting that musical aptitude is affected by a combination of genes involved in the auditory pathway. The perception of music starts with specialized hair cells in the inner ear, which transmit sounds as electronic signals through the auditory pathway to the auditory cortex, where sounds are primarily recognized. In addition to simple sensory perception, the processing of music has been shown to affect multiple other regions of the brain that play a role in emotion, learning and memory.
Research reveals that the brain’s motor network helps people remember and recognize music that they have performed in the past better than music they have only heard. A recent study sheds new light on how humans perceive and produce sounds, and may pave the way for investigations into whether motor learning could improve or protect memory or cognitive impairment in aging populations.
The study, published in the journal Ear and Hearing, looked at the habits of 160,000 people in the UK aged 40 to 69 years. It found 10.7 per cent of adults had significant hearing problems when listening to speech in the presence of background noise - but only 2.1 per cent used a hearing aid.
One in 10 middle aged adults had substantial hearing problems and were more likely to be from a working class or ethnic minority background.
Dr. Piers Dawes, from The University of Manchester’s Audiology and Deafness research group, said: “This is the first study to describe the prevalence of difficulties understanding speech in background noise in a large sample of the population, anywhere in the world.
“It shows hearing aids remain significantly under used despite significant improvements in both technology and their provision, and a high proportion of people who would benefit from treatment may not receive effective intervention.
“Reasons for the lack of uptake might be lack of awareness of treatment options, lack of recognition of their difficulties, finding hearing aids uncomfortable or finding them of limited help.”
The University of Manchester team is the first group in the world to gain access to the large UK database from the UK Biobank allowing them to study the habits of 160,000 UK adults.
Professor Kevin Munro, Ewing Professor of Audiology at The University of Manchester who also worked on the study, said: “There still seems to be a stigma attached to wearing a hearing aid, where as there is little stigma now associated with vision loss and wearing spectacles. “This might be because eye care also involves lifestyle choices - it’s available on the high street without the need to see a GP and onward referral to an audiologist in hospital, which emphasises illness and frailty.”
By Rebecca Grundy MSW., RSW
Program Director, Counselling Services
I recently read this article on a new study linking hearing loss and depression, “Especially for women, hearing loss linked to depression”. The findings of this study seem to reflect the experience of persons with hearing loss that contact our counsellors here at CHS. We see anxiety and depression in people learning to live with a newly acquired hearing loss or with a progressive hearing loss.
Grandmothers struggle to understand their young grandchild’s speech. Women experience the stigma of hearing loss in the workplace as their colleagues chat about the local news at lunch. Grieving the loss of hearing may include loss of relationships, loss of status in the community and bring stress to everyday communication situations at the bank, grocery store, or the playground.
Our counsellors understand the loss experience and are here to assist a person coping with this loss. CHS counsellors are here to support people in learning more about their hearing loss, effective communication strategies and how to explain this to others in their life, thereby mitigating isolation and withdrawal - common symptoms of depression. CHS promotes hearing health care, counselling services and is a good resource for those with hearing loss.
A group of deaf adults using American Sign Language in a healthy lifestyle program successfully lost weight, according to a study presented Wednesday.
In the first randomized trial of lifestyle modification or weight reduction with deaf people using American Sign Language, participants had moderate improvements in their weight and level of physical activity after a 16-week program.