Audiology and Hearing

Hearing loss in low- and middle-income countries

Over 5% of the world population is living with a disabling hearing loss, with the majority of those individuals living in low- and middle-income countries (LMICs). Yet, only a tiny percentage of hearing aids, cochlear implants, and other hearing services are delivered to those in economically deprived regions.

We work with local partners in LMICs to conduct and analyse epidemiological investigations in order to better understand the needs of their populations. We conduct projects which aim to elucidate the benefits and limitations of current service provision in LMICs. Our research program encompasses evaluations of the effectiveness and practical limitations of hearing service delivery in LMICs. The wider goal of this research program is to reduce the barriers to accessing hearing services and rehabilitation globally.

How the brain creates a sense of auditory space

Prof McAlpine’s ARC Laureate Fellowship

Spatial hearing is necessary for locating the source of a sound, and critical for communication in noisy listening conditions. The object of this project is to determine how the mammalian brain, including in human listeners, represents sensitivity to interaural time differences, one of the two binaural cues, and how this representation is transformed from the brainstem to the cortex. Anticipated outcomes include a coherent model of binaural hearing that links cellular, systems and perceptual investigations, and an understanding of the human auditory brain that should facilitate novel technologies and interventions to improve hearing function.

Designing patient-centred and evidence-based hearing healthcare services, pathways and solutions

Multiple solutions exist to support hard-of-hearing individuals in their communication. The uptake of these solutions, however, is low. Effectiveness data and cost/benefit analyses are lacking to objectively compare the solutions available. And no standard referral pathway exists throughout the lifetime to support hard-of-hearing individuals and their families in their learning, work, and social environments. We established The Centre for Implementation of Hearing Research (CIHR) to gather relevant stakeholders to work together towards re-thinking and re-designing our service models and care pathways. This includes the way that we develop, conduct, and interpret research projects and how reliable knowledge can be shared with, and more easily be used by, clinicians and clients.

The Centre for Implementation of Hearing Research is directed by Professor Catherine McMahon. More information about the Centre can be found here.

Improving diagnostics, devices and interventions

Our brain adapts to the stimulation it gets. In the case of hearing, the brain adapts to the sounds, speech, and music it is exposed to. This adaptation is much more effective at a very young age, during the period when language is developing. In adults who have lost their hearing over time and have used different types of amplifications, it is difficult to estimate the quality and magnitude of speech stimulation their brain has received, and consequently, how it has adapted to hearing loss. In addition, current standard audiology tests are limited in their ability to inform on real-life everyday listening difficulties. By developing more real-life evaluations of listening abilities, gaining a better understanding of how the brain adapts to hearing loss and how it can further adapt to interventions such as hearing aids, cochlear implants and training, we aim to increase prognostic precision and monitor intervention benefits. To investigate this, our researchers measure electric and magnetic signals emitted by the brain. In particular, we are involved in the development of a unique magnetoencephalography (MEG) prototype device that has been designed to be compatible with cochlear implants, in collaboration with the Centre for Cognition and its Disorder (CCD), and the Kanazawa Institute of Technology (KIT) in Japan. Our expertise also centres on recreating 3D virtual acoustic environments (such as can be used in the AHH anechoic chamber), continuous speech and conversation tests, and using artificial intelligence to develop improved signal processing strategies for hearing devices, to overcome the main challenge of listening in noise.

Auditory processing

Many children and adults experience difficulties hearing in a noisy environment, even though their audiogram suggests that they have normal hearing. While in the past it has been suggested that it could be related to attentional difficulties, no consensus has been reached. Growing evidence suggests that current audiological tests lack the sensitivity to clearly identify what causes these difficulties. Here we investigate how monaural and binaural auditory processing, cognitive and linguistic skills are affected by noise exposure. Another aim is to determine whether music training provides a protective mechanism. Concepts such as central gain: when the brain increases a signal it cannot perceive anymore (similar to a phantom limb), are explored. Similarly, the relationship between developmental abilities such as attention, memory, listening and reading is also investigated.

Hearing loss and mental well-being

Around seven in ten people over the age of 65 live with either sight or hearing loss and over two-thirds live with depression and other mental illnesses. Dementia and cognitive impairment steadily rise in prevalence over the age of 65 to the point where almost one-third of people at the age of 90 are affected. Hearing and vision loss interact with cognitive declines to worsen quality of life, reduce function, increase dependency and care costs. Less than one third of people with sensory/cognitive impairment receive treatment, with marked age, gender, socio-economic and ethnic inequalities in those who do.

Hearing and vision impairment are markers of risk for cognitive decline and dementia. We use epidemiological modelling to understand relationships between hearing and vision impairment and cognitive decline, dementia, depression and anxiety as well as modelling the impact of sensory interventions on mental well-being outcomes. We work to improve early detection and diagnosis of sensory, cognitive and emotional problems in older people through specially adapted assessment and development of evidence-based clinical guidelines. We work with patients and the public to co-develop and evaluate sensory interventions to improve mental well-being outcomes. We provide new information about the economic impact of sensory impairment on mental health and use of health services for older people, and on the cost effectiveness of sensory support to improve mental well-being, quality of life and provision of services.

An integrated approach to research, teaching and hearing healthcare

Our integrated approach to Hearing healthcare encompasses world-leading discovery and translational research, excellence in clinical care at our MQ Health Speech and Hearing Clinic, and a high-quality Master of Clinical Audiology program.

To facilitate the development, teaching and implementation of patient-centred, applicable, desirable and cost-effective interventions that are anchored in a rigorous and up-to-date evidence-base, our researchers are also clinicians, innovators, and educators, and work collaboratively towards best patient outcomes.

For example, our clinicians were involved in the international eHearing study, which seeks to understand the barriers and facilitators to hearing healthcare in adults >65 years of age across 4 countries; USA, Australia, UK, and Canada.

Master of Clinical Audiology students also engage in an independent research project providing hands-on experience in the underpinning research that supports Audiology training and services. Amongst others, these projects have supported research in remote Australian communities and developing countries.