April 2017 KSHB Kansas City

Layla Walker's piano playing is music to her family's ears, but not to hers. "Today I am going to get my cochlear implant turned on," she said. "It's going to be super cool. And guess what - I'll be able to hear everything, even birds singing. I've never heard birds singing before.” Layla is blind and mostly deaf. The 16-year-old has lived the majority of her young life in total darkness and silence.

"When I think of certain colours, I think of the thing it relates to," Layla explained. "Like blue, I think of ocean and red, I think of a heart. Not being able to hear, it's most difficult for me because I can't hear where in the world noises are coming from.” But that changed when her audiologist activated her cochlear implant. 

"There is a really big advantage that comes with connecting with your world via sound," explained Jamie Governal with St. Luke's Hospital's Midwest Ear Institute. "For Layla, it's even more important because of her vision loss. It's really awesome for kids to be able to hear their parents voices, hear birds chirping, all those things we take advantage of day-to-day.” But as cool as it is, the cochlear implant goes beyond helping Layla hear a bird's song; it is a stepping stone to her independence. "When she can cross a certain level of independence, she can have a guide dog, so that way she can have the ability to have even more independence," explained Layla's dad Jason.  And while she has big dreams, for today, Layla wants to enjoy the simple things.

"I am going to try to talk to my parents and my siblings and maybe try to play the piano, and see what that sounds like," said Layla.

April 2017 Starts at 60

A video of a baby boy hearing his mother and father speak for the first time has been warming hearts around the world. Lachlan was diagnosed at birth with moderate-to-severe hearing loss in both ears and was just seven weeks old when he was fitted with hearing aids on each ear by Australian Hearing.  His parents say they cried tears of happiness when his hearing aids were switched on and they saw his face light up at the sounds around him. The magical video of Lachlan been viewed over 4 million times since it was uploaded to the internet in 2014, and continues to be viewed today.  It’s one of many online videos showing people hearing for the first time or recovering their hearing, and they almost always end in tears of happiness. 

LachlanAustralian Hearing audiologist Emma Scanlan has been present at many moments like the moving ones caught on video. She says witnessing babies like Lachlan hear for the first time, or seeing an adult patient hear again after years of silence, is always emotional. “We’re all crying by the end of it,” she says. “I’ve seen both children and adults hearing for the first time or hearing again after a very long time of really struggling to hear. They’re a bit shocked at first generally. You can see they start to smile especially when it’s the parents there in front of them and they then associate that sound with the parents very quickly and it becomes a very joyful experience.”

But many Aussies are waiting too long for their own moment like this. Hearing loss affects one in six Australians, ranging from sensorineural hearing loss – often caused by ageing – to conductive hearing loss, which can be caused by a blockage in the ear or damage to the hairs in the inner ear.

However, on average, Australians put off getting their hearing tested seven years after they first start to notice changes. Scanlan says Australian Hearing is working to close the gap here because so many people are living with hearing difficulties instead of addressing the issue. “The people that do the best are the people who act immediately,” she explains. “Our hearing naturally declines with age because the hairs protecting the inner ear start to deteriorate.” The inner ear is filled with tens of thousands of little hairs and through repeated use or through battering from noise as we get older, these hairs lose their elasticity and don’t work quite as well as they used to,” Scanlan says.

She said hearing aids, cochlear implants or a combination of both are all popular options for those dealing with complete deafness or hearing loss.

March 2017 Science Daily

Cochlear implants provide many deaf people with a significantly improved ability for oral understanding and a considerable boost to their quality of life. However, despite the technological advances, there are still some 5 to 10% of adult patients for whom this technique remains stubbornly ineffective. Why? In order to find an answer to this question crucial for clinical practice, Diane Lazard, an ear, nose and throat surgeon at the Institut Vernes (Paris) and Anne-Lise Giraud, neuroscientist in the UNIGE's Faculty of Medicine, have sought to identify which brain factors might be linked to the success or failure of implants. The two scientists have studied how the brain of a deaf person manages to represent the sound of the spoken word and its capacity of re-using these representations after a cochlear implant.  Giraud explained: 'The test went like this. We presented some visual stimuli to the subjects, in the form of written word, and asked them to determine whether two words, without the same orthographic ending, rhymed or not -- for instance wait and gate. Subjects would then have to recourse to their memory of sounds and, using functional neuroimaging (fMRI) techniques,  we observed the neural networks in action.' 

brains

 Top: red shows right occipito-temporal coupling during deafness, indicating a poor cochlear implant prognosis. Below: blue shows right occipito-tempora uncoupling after deafness, indicating a good cochlear implant outcome

Whereas the researchers were expecting that the subjects would be slower and less accurate that those in a control group of people without any hearing difficulty, to their surprise they found that certain deaf people completed the task quicker and more accurately than their normal-hearing counterparts.  For these 'Super-readers', who appear to be able to handle written words quicker than those with no hearing impediment, the brain has opted to replace orality by written exchanges and has restructured itself accordingly. The brain circuits used by such 'super-readers', situated in the right hemisphere, are organised differently and cochlear implants actually give poor results. The other deaf people, those who carried out the task at the same speed as the control subjects, remain anchored to orality and gained more benefit from cochlear implants. Unlike the 'super-readers', the latter manage to master lip-reading as deafness encroaches, and therefore maintain a central phonological organisation very similar to that of normal-hearing people, which uses the left hemisphere of the brain. There are therefore two categories of subjects whose brain circuits function very differently.

This research points to the essential role played by the interactions between the auditory and visual systems in the success or failure of cochlear implants. Their outcome will indeed depend on this cortical reorganisation. For 'super-readers', the fact of having adapted to deafness by developing certain "supra-natural" visual capabilities constitutes a handicap for the use of implants. Is it possible to go back in time? 'It's difficult to say at the moment,' says Lazard, 'but the idea is also to be able to spot in advance the people who will have a propensity for the written stimulus and to offer them active means for remaining with orality, particularly with auditory prostheses and speech therapy used much earlier than is currently practised.' But as Giraud explains, 'Equally we do not know why certain people quite unconsciously choose one direction rather than the other, but predisposition surely plays a part, because we all learn to integrate auditory and visual information by the time we are three. Certain people manage this better than others and, with deaf people, those who integrate the audio-visual elements best will probably have a tendency to remain more aligned with orality.' Such results also explain why it is so important to be able to equip congenitally-deaf children during their first few months, i.e. before the onset of the reorganisation of the visual and auditory brain circuits, a process which may compromise their ability to access orality.

 

May 2017 newswire; indiana university

Researchers at Indiana University School of Medicine have successfully developed a method to grow inner ear tissue from human stem cells—a finding that could lead to new platforms to model disease and new therapies for the treatment of hearing and balance disorders. “The inner ear is one of few organs with which biopsy is not performed and because of this, human inner ear tissues are scarce for research purposes,” said Eri Hashino, PhD, Professor of Otolaryngology at IU School of Medicine. “Dish-grown human inner ear tissues offer unprecedented opportunities to develop and test new therapies for various inner ear disorders.” The study, published in Nature Biotechnology, was led by Karl R. Koehler, PhD, assistant professor in the Department of Otolaryngology and Head and Neck Surgery at IU School of Medicine, and Dr. Hashino in collaboration with Jeffrey Holt, PhD, professor of otology and laryngology at Harvard Medical School and Boston Children’s Hospital. The research builds on the team’s previous work with a technique called three-dimensional culture, which involves incubating stem cells in a floating ball-shaped aggregate, unlike traditional cell culture in which cells grow in a flat layer on the surface of a culture dish. This allows for more complex interactions between cells, and creates an environment that is closer to what occurs in the body during development. 

Inner ear organoidHuman inner ear organoid with sensory hair cells (cyan) and sensory neurons (yellow). An antibody for the protein CTBP2 reveals cell nuclei as well as synapses between hair cells and neurons (magenta).

By culturing human stem cells in this manner and treating them with specific signaling molecules, the investigators were able to guide cells through key processes involved in the development of the human inner ear. This resulted in what the scientists have termed inner ear “organoids,” or three-dimensional structures containing sensory cells and supporting cells found in the inner ear.

“This is essentially a recipe for how to make human inner ears from stem cells, said Dr. Koehler, after tweaking our recipe for about a year, we were shocked to discover that we could make multiple inner ear organoids in each pea-sized cell aggregate.” The researchers used CRISPR gene editing technology to engineer stem cells that produced fluorescently labeled inner ear sensory cells. Targeting the labeled cells for analysis, they revealed that their organoids contained a population of sensory cells that have the same functional signature as cells that detect gravity and motion in the human inner ear. “We also found neurons, like those that transmit signals from the ear to the brain, forming connections with sensory cells,” Dr. Koehler said. “This is an exciting feature of these organoids because both cell types are critical for proper hearing and balance.”

Dr. Hashino said these findings are “a real game changer, because up until now, potential drugs or therapies have been tested on animal cells, which often behave differently from human cells.” The researchers are currently using the human inner ear organoids to study how genes known to cause deafness interrupt normal development of the inner ear and plan to start the first-ever drug screening using human inner ear organoids. “We hope to discover new drugs capable of helping regenerate the sound-sending hair cells in the inner ear of those who have severe hearing problems,” Dr. Hashino said.