The first two articles of this three-part series discussed the differences between two models of rehabilitation and explored how an open systems model called the The Model of Human Occupation1 (MOHO) might be applied to an hypothetical case of an amputee. The purpose of the present article is to raise the awareness of the hearing health care professional relative to how the open systems model might apply to hear-impaired patients.

It may be helpful for the dispensing professional first to determine which model is in current use in their practice. The Reductionist Model (see Part 1 of this article in the Feb. 2001 HR, pgs. 32-33) is in use when the patient provides the practitioner with a list of symptoms, and the practitioner looks for signs via audiometric testing, otoscopy, etc., then determines that the patient has (or does not have) a hearing loss.2 A suitable hearing device is recommended, and the patient leaves the office expecting that his/her problem will be solved with the use of a hearing instrument. After the hearing instrument is fitted, it may be re-programmed during each patient visit. This model is called “reductionist” because the focus is on examining components (signs and symptoms) to determine the problem (hearing loss) and its solution (hearing instrument), all within a specific framework of the physical and neurological components of the auditory system.

If, during future visits, the patient complains that the hearing instrument is not working properly or is physically uncomfortable, then the practitioner either reprograms or modifies the hearing instrument (often changing and upsetting other parameters during the process). If the problem is solved, no further action is taken. If the problem is not solved, the fault may be seen to lie with the hearing instrument, which is sent back to the factory for remake or repair.

Sometimes the practitioner will order another brand of hearing instrument. Eventually, if the problem remains, the hearing instrument may be sent to the factory as a credit return—or worse, the client becomes frustrated and starts believing that “there is nothing that can be done” about his/her hearing problem. They may also decide to try another dispensing office, or may decide that their hearing is not “bad enough” to be worth the trouble.3 This entire process should be considered crude and costly to everyone involved; certainly, it is not a model of effective rehabilitation.

Hearing loss has far-reaching effects on many things a person is, has and does. Success is sorely limited when the reductionist model, which negatively affects the patient, is adhered to. The dispensing professional, the client and the hearing industry in general become the losers. In many of the above cases, the practitioner plays the role of a salesperson and mechanic—not a rehabilitative consultant and professional.

The Open Systems Model Applied
The open systems model is in place when the practitioner has his/her office set up so that rehabilitation actually begins with the setting of the appointment. At this point, the patient is advised to be accompanied by his/her spouse during the hearing test.4 Once in the waiting room, the couple is given an holistic questionnaire to complete, designed to elicit information about the impact of the hearing loss on the patient’s family and friends, his/her behavior and ability to function within the listening environment.3

At some point between the test and delivery of the new hearing instruments, the patient and spouse are informed about aspects of hearing loss, such as phonemic regression, spatial function and loudness growth abnormalities.5 They are told what to expect from the new aid(s) and how long the neurological adaptation for optimum restoration will likely require.6

They will also be told what amplification limitations they can expect relative to their hearing loss, thus preparing them for the need to obtain appropriate assistive listening devices (ALDs) and to develop compensatory strategies for daily living.7,8 The open systems model covers a wider range of difficulties associated with hearing loss from which the patient can feel that the practitioner is looking after his/her best interests, thus lessening the risk of returning the hearing instruments during the trial, though not all of the desired objectives can be met within the arbitrary 30-day period.

Back to the MOHO
Taking the open systems model a step further, the occupational-therapy based MOHO (Fig. 1) applied to hearing loss could have a positive impact on all those involved. The internal portion of the model consists of three subsystems: volition, habituation and performance.

figure 1
Fig. 1. Diagram of the Model of Human
Occupation (MOHO).

Volition is concerned with one’s values, beliefs and interests. It is considered the most important of the subsystems in human behavior. Information taken in by an individual from the environment (objects, tasks, society, culture) flows firstly through volition.

How that information integrates with volition has an impact on habituation (one’s roles, habits and self-image). The accumulating information then acts upon the performance subsystem (symbolic, neurological and musculoskeletal), and results in behavioral responses. This behavior has an impact on the surrounding environment, and the consequences of the behavior return to the individual’s system via a feedback loop. Feedback information can be positive or negative. After feeding again through the internal subsystems, it will either reinforce present behavior or begin to modify or change behavior, for better or worse.1

How can such a complicated model be applied to the hearing health care field? It is important to realize that hearing loss is a complicated issue. It affects many aspects of human functioning, not the least being human emotion.3

Personal Causation
Personal causation represents one’s conviction that he/she has the ability to carry out a number of skills. When one experiences failure in certain activities because of hearing loss, self-belief begins to waver, and the individual begins to lose confidence.

Avoidance strategies may begin to develop. A simple example is the telephone. The individual may no longer answer the telephone, and eventually the support system of family and friends begins to diminish as more and more communication is directed to the (more) normal-hearing members of the family who do answer the phone.3

Expectancy of success or failure: One expects success or failure based upon past experiences.1 Expectancy of failure always produces anxiety, and anxiety can present itself as aggression. If a patient has had several failed attempts at wearing hearing instruments, then he/she may enter the hearing care office with a pessimistic viewpoint, coupled with an aggressive demeanor that will signal to the dispenser that the person is “difficult to deal with.” Understanding the cause behind this behavior will allow the professional to defuse a potentially negative situation.

Respecting the Technology: Almost every patient who steps inside a hearing care office values money. Hearing instruments are perceived as expensive, albeit the result of many hours of fine technical work by highly trained individuals. Dispensing professionals communicate the value they place on a hearing instrument by the way they handle the device. If it is handled lackadaisically, the patient’s interpretation is that the hearing instrument is nothing more than just a piece of an ordinary hardware. The patient places a higher value on an aid that the dispenser handles in much the same way as a jeweler would handle a delicate piece of jewelry: Carefully removing it from its presentation case and pointing out its fine workmanship.

Valuing Relationships: The need to correct a person’s hearing loss gains importance when that person realizes that his/her grandchild has stopped communicating with him/her because it has become too difficult. Or that the spouse no longer feels that he/she is loved because softly spoken words of kindness have been neither heard nor returned. Loud, to most people, means aggressive. It is also almost impossible to smile while speaking loudly or shouting. Additionally, for those with hearing loss, loudness can have a potent effect upon the amygdala of the human brain, the primitive seat of emotion, causing an anxiety-triggered reaction of fight or flight.3

Interests play an important role in how people spend their time. Some interests are social; some are solitary. Some are physical; some are sedentary. An interest checklist helps to identify those pursuits in which the patient once participated.1 This assessment allows the practitioner to open discussion about why the patient no longer attends club meetings or church, for example. This is an excellent opening for advice on FM listening devices or how to use the volume control of the hearing instrument so that former interests may be resumed.

Everybody has several roles during their lifetime—child, parent, club member, employee, etc. When people adopt a role, they internalize obligations of that role, and they have a perception of how others see them in that role. A discerning hearing health care practitioner will acknowledge the various roles of clients, observing how the hearing loss impacts the patient’s ability to perform in that role. The attorney, struggling to hear in a courtroom, is an example of a learned professional feeling that he is coming across to his peers as no longer able to function adequately. Information returning via the feedback loop (Fig. 1) may foster a belief that he is inadequate.

Habits comprise one’s typical use of time, and also concern the individual’s flexibility with routine. A useful example is whether one is in the habit of waking early. If not, does one have to be awakened by an audio alarm clock in order to keep early morning appointments? When the alarm cannot be heard due to severity of hearing loss, a flashing light or vibrating alarm may be a welcome addition to their armamentarium of assistive devices.

There are three broad types of skills: 1) motor skills (ability to move and to manipulate objects), 2) process skills (ability to plan and problem solve), and 3) communication skills (the ability to interact).1

The hearing care professional should be very familiar with this part of the open model, but its inclusion in a checklist is necessary to illustrate its place in the model. There are four reflexes of the ear (tympanic, trigeminal, vagal and lymphatic) which can potentially create fitting problems. These may unknowingly be overlooked, despite the problem-solving battery of skills the practitioner utilizes during fitting hearing instruments.9

The practitioner should also note other signs of neurological and/or cognitive dysfunction. When a patient has suffered a cerebral vascular accident (stroke), he/she may suffer residual effects such as spatial problems or problems with muscular movements and dexterity (i.e., proprioception). This patient will need more attention from the practitioner in training to use a hearing instrument and appropriate assistive devices.

The environment involves everything that we have around us that we see, hear, smell and touch. It includes how the patient can handle the hearing instrument (objects and tasks), how he/she can distinguish near sounds from those in the distance (spatial separation) and where the patient is in relation to others (spatial mapping). A discerning practitioner will use the patient’s environment as an important rehabilitation tool. The dispensing professional needs to know how the patient’s living room furniture is arranged if the hearing instrument is not effective at improving hearing in multi-talker environments or at times when the television is blaring. Additionally, the professional needs to have at least some awareness of the patient’s social structure and support systems.

The MOHO is, in its entirety, complex. It is designed to cover multi-faceted rehabilitative needs faced by occupational therapists. Hearing health care, using this model, can also be seen as complex, from the microscopic aspects of the ear and its neurological companions to the macroscopic aspect of the human and his/her function within the environment.

It is hoped that this series of discussions on various aspects of rehabilitation will stimulate further the progress that has been seen, felt and heard among hearing health care professionals throughout past decades of progress and innovation.

Chartrand Glenys A. Chartrand is an occupational therapist from New Zealand who, along with her husband, Max, conducts aural rehabilitation seminars. She also serves as a field coordinator for United Hearing Systems.

Correspondence can be addressed to HR or Glenys Chartrand, United Hearing Systems, 731B Norwich Rd., Plainfield, CT 06374; email: [email protected].

1. Kielhofner G: A Model of Human Occupation: Theory and Application. Baltimore: Williams and Wilkins, 1985.
2. Wilcock A: An Occupational Perspective of Health. Slack Inc., 1998.
3. Chartrand M: Hearing Instrument Counseling ( 2nd Edition). Livonia, MI: International Institute for Hearing Instrument Studies, 1999.
4. Chartrand M: Effectively Utilizing Third Party Psychology in the Evaluation Process. Audecibel 1998; Sept-Oct: 11-14.
5. Chartrand M: Psycho-Social Principals of Hearing Impairment. In RE Sandlin’s (ed) Hearing Instrument Science & Fitting Practices (2nd Edition). Livonia, MI: International Institute for Hearing Instrument Studies, 1996: 755.
7. Chartrand M: The Need for Aural Rehabilitation in Today’s Dispensing Practice: Part 3. Hearing Professional 2000; May-June: 5-11.
8. Chartrand G: Concepts of Rehabilitation: Part 2: Application of System Models. Hearing Review 2001; 8 (3): 64-66,92.
9. Gatehouse S & Killion M: HABRAT: Hearing Aid Brain Rewiring Accomodation Time. Hearing Instrum 1993; 44 (10): 29-30.
10. Chartrand M: In Vigorous Defense of the (Lowly) Volume Control. Hearing Professional 2001; May-June: in press.