Behavioral audiology (BA) is based on a simple question: How do changes in an individual’s auditory status affect their overt and covert behaviors, specifically, but not exclusively, their receptive communication function? This leads to the corollary: What changes can we, as audiologists, effect in a client’s auditory behavior to improve their receptive communication function?
BA is now in its infancy as a clinical discipline but has its roots right back at the start of modern audiology following World War II when its focus was on the difficulties experienced by U.S. Veterans as a result of traumatic changes to their auditory status.
At that stage, knowledge of auditory function was basic, almost entirely based on the behavioral changes noted in people with abnormal pure-tone audiometry. There was little or no appreciation of the subtleties of the auditory process that have become apparent in greater detail recently, but nevertheless, audiological interventions were based on treating the Veteran’s receptive communication difficulties, as a behavioral audiologist might describe them now.
To understand how BA is different from conventional audiology practice, we must look very carefully at the phenomena with which are working. This close examination has not been carried out in the past (the early assumptions have not been challenged) and, as a result, there is a lot of confusion, both within and outside of our profession. Hopefully, you will see how BA can reduce this confusion as you read on.
We are dealing with highly complex phenomena, but our everyday language does not have well-defined concepts for us to describe these. The common language words such as hearing, especially, has multiple meanings. The jargon we have developed in audiology to describe1 these phenomena is very loose, and as we begin to uncover the complexities of our area, its inadequacy becomes clearer.
1 For instance, witness the controversy that rages about the term (central) auditory processing disorder (Moore, 2018; Iliadou et al; Keith et al, 2018; Ryals, 2018), and (the embarrassing) hidden hearing loss, and the commonly used hearing loss. These are all terms we use to try to describe the phenomena we are working with.
To escape this quandary, we need to re-examine the phenomena we are dealing with fresh eyes and develop very strict definitions. BA uses new definitions to help us with these complexities.
If we were to start anew in our field with fresh eyes (and somehow with our current knowledge of auditory function), we might ask what is the most common complaint our clients bring to us? I think we would agree that, for many of our clients, it is difficulty understanding what other people are saying to them in certain circumstances. If we view this complaint with no preconceptions, we might conclude that this refers to a situation-dependenti problem with our clients’ “receptive communication function.”ii But is this not a hearing problem, you might ask? No, because most of our clients, with the obvious exception of the smaller proportion who have severe or greater degrees of deafnessiii, can hear (i.e., detect and recognize) environmental sounds quite adequately. Rather, it is a listeningiv problem.
Many audiologists recognize in print the inadequacy of writing about hearing loss and will often use terms such as hearing and listening (e.g., Moore, 2018). However, this conflates two quite different functions (see Endnotes). We cannot hope to unravel the complexities unless we can think clearly about them and to do that, we need to start with clearly defined terminology.
Once we agree on a precisely defined terminology, we can start to examine the phenomena more closely. It then becomes apparent that the standard audiological assessment battery is inadequate for this, and we need to use more tools to unravel the mystery.
Models are a way of helping us to understand complex phenomena. Since its inception, audiology has adhered to a medical model that has always treated receptive communication difficulties because of hearing loss (deafness) including, more recently, (central) auditory processing disorder (APD). This has created a dichotomy that I feel is particularly damaging to our profession and does a disservice to our clients. Attempting to fit the functional phenomenon (reduced receptive communication) into a medical diagnosis (deafness versus APD) has created immense confusion2.
2 See Vermiglio (2014) for example, for an excellent discussion on clinical entities in audiology. Using the Macroaudiology concept of auditory efficiency (q.v.) sidesteps this dichotomy and simplifies the behavioural audiological understanding of the problem; this will be distinct from the medical model.
To help me in my work, over the past 30 or so years I have developed the “Macroaudiology”3 Model. To my knowledge, this is the first model of its kind in audiology. There may have been similar recommendations made in the past, but it is clear they have not entered the mainstream. My model is based on considerations of what a normal listener must be able to do to achieve a normal level of receptive communication function.
3 Readers interested in learning more about the Macroaudiology model are encouraged to contact me.
The model was developed from considerations of the receptive communication difficulties my clients described to me, and what changes in their auditory function I could detect that could possibly give rise to these difficulties. I was able to develop a systematic approach to assess the auditory efficiencyv of clients aged five years and older by using commonly available audiometric tools, but often with novel interpretations. I borrowed from the work in auditory processing previously done by others (e.g., Bellis, 1996, 2003; Katz, 1982; Plomp, 2002) developed some new concepts, extended other concepts, such as those related to information transmission. (Edwards, 1969)
Information gathered from this assessment identifies a few factors influencing auditory efficiency and thus auditory behavior. These factors appear to have face validity in that they tie in with client’s experiences4, and allow me to make predictions regarding a client’s listening experiences and recommendations for audiological intervention.
4 As a sole practitioner, I unfortunately do not have the resources to rigorously test this model. The assessment battery needs to be assessed psychometrically, and critically reviewed in terms of its efficiency.
Using this systematic approach, it is possible to identify factors that contribute to a client’s complaints. This precludes the necessity of resorting to unhelpful designations such as auditory processing disorder or hidden hearing loss. By focusing on the functional aspects of a client’s presentation, and not worrying too much if we (the experts) cannot identify a cause or site of lesion5, we can address the client’s concerns directly.
5 The audiological information gathered during BA assessment easily exceeds that obtained in a traditional audiological assessment and has the same value for our medical colleagues, to whom we can refer our clients if we suspect a medical issue.
Complexities of Listening
We are still in the early stages of developing our understanding of the complexities of listening, and we should not be ashamed that our understanding is not complete. Approaching the study of listening from a functional point of view and sharing our insights with others in the profession will eventually increase our understanding and our ability to assist our clients and, hopefully, make a positive contribution to society.
Our expertise comes in our ability to integrate our client’s experience with what we do understand about listening; having a model as a roadmap is of great benefit in this. The validity of our clinical observations of our clients’ receptive communication difficulties does not depend on whether we can identify a site of lesion, or even where our clients’ auditory function lies with respect to normative data; our focus as behavioral audiologists is on their auditory behavior.
This type of analysis is currently very time-intensive6 but it yields a fine-grained picture of a client’s auditory status that can give clear indications of what interventions might be indicated. In conjunction with the clinical interview and questionnaire data, it also allows production of a narrative report for the client that helps to demystify the client’s difficulties so that they can understand what is happening and empower them to develop their own strategies for management.
6 I can envision a time when we have refined the procedures we use for greater efficiency and descriptive power.
We should not begrudge the time investment in these assessments. We are trying to understand a highly complex process that we all agree is central to our client’s well-being. Obviously, this approach will not be suited to medically-orientated settings, such as hospital clinics and otology practices, where the consumer (patient) receives expert advice, or to businesses whose sole focus is the sale of hearing instruments to the consumer (customer).
BA practices are more like specialized psychology practices, where the consumer (client) embarks on a journey with the practitioner as a guide. The goal of the journey is client empowerment and greater practitioner insight.
Listening Effort and Auditory Stress
One of the key concepts of the Macroaudiology Model is listening effort.vi As the quality of the listening environment is reduced, and/or auditory efficiency decreases, so the proportion of cognitive behavior to the listening process is increased. This happens to all of us when we listen in challenging situations, or when we try to understand a talker in a language/jargon in which we are not fluent, for instance.
This increased cognitive effort is tiring and stressful and can lead to the Macroaudiology concept of auditory stress. Chronic auditory stress can often be identified in clients reporting problematic tinnitus or hyperacusis. This association can point to reasoned (based on specific evidence) novel behavioral approaches for management of these conditions.
BA assessments acknowledge the inextricable link between auditory function and cognitive processes in listening behavior; there is no attempt made to tease out “modality-specific” status. Such an attempt may be of use in the laboratory, but it has little value in assessing real-world functioning that is the goal of BA.
The BA client-audiologist interaction is not concerned with the etiology of the auditory inefficiency, but rather its functional effects. Because the functional consequences of auditory inefficiency from peripheral factors are virtually indistinguishable from those arising from central factors, the audiologist’s repertoire of intervention is the same. The question for the behavioral audiologist is the same: What interventions are indicated in this client’s clinical presentation to optimize their receptive communication function, regardless of etiology?
Because reduced auditory efficiency results in reduced receptive communication function, it necessarily has psychosocial consequences. BA recognizes these direct consequences and allows the practitioner to offer behavioral interventions to increase and maintain communication confidence and the client’s preferred level of social engagement. It also helps us to better appreciate the dynamic which occurs between talker and listener in failed communication, and how this can impact a client’s communication confidence, self-confidence, and self-esteem.
BA provides the bridge between the arcane complex world of auditory function and a client’s everyday experience that is missing in conventional audiology practice. It facilitates rapport between audiologist and client and helps a client to have confidence that their audiologist understands their condition.
A Return to Audiology’s Roots
BA harks back to the early conception of audiology post World War II with its focus on receptive communication difficulties. It differs from that early concept by incorporating up-to-date concepts of auditory and cognitive function, allowing more sophisticated intervention. Working in BA is not difficult but can be hugely rewarding if you are of an enquiring nature, as your understanding of the interface of the acoustic world and auditory perception deepens. It can be difficult to make the transition from the standard model, but this will be easier if you can accept that the proper area for most audiologists is helping people with their listening problems.
I believe that BA offers a way to simplify our approach to this complex field. By adopting terminology such as auditory efficiency, we can present our services not only to our clients but also to third-party funders. Currently, the confusion of terminology makes it difficult for non-audiologists to understand that the listening difficulties of some people with normal pure-tone audiometry are valid, and as deserving of audiological intervention as those with abnormal pure-tone audiometry.
Similarly, other professions that rely on our assessment of a client’s receptive communication difficulties are baffled by our inability to provide them with clear indications of a client’s auditory strengths and weaknesses, and guidelines for intervention (e.g., Hardin and Kelly, 20197). As a profession, audiologists have a responsibility to ensure that our services are available to all those who need them, not just a particular subgroup who share a particular clinical presentation; as a profession, we are failing a significant proportion of the population. This will require us to assess and analyze our clients’ auditory function in ways that identify individual differences and can individualize audiological intervention.
I am calling for the creation of a new formal branch of audiology, behavioral audiology. Behavioral audiology can be taught to students and practicing audiologists. It is a functional approach to clients’ receptive communication difficulties, in contrast to the prevailing medical approach that is clearly inappropriate for functional problems.
Behavioral audiology assessments provide at least as much audiometric data as the current standard assessment, so there is no loss of linkage with medical and surgical services, but they put the client squarely in the center of the assessment, allowing us to use our expertise to develop a sensitive understanding of each client’s unique needs.