Why is it difficult to understand words with hearing aids?

Hearing loss is categorized into three types: conductive, sensorineural, and mixed.  A conductive hearing loss means there is an issue in the middle ear space (ear drum and middle ear bones) causing the hearing loss; a sensorineural hearing loss means there is an issue in the inner ear and/or beyond, and a mixed hearing loss is a combination of a conductive and sensorineural hearing loss.  The type of hearing loss can be tested during a hearing evaluation using air- and bone-conduction measures.  When there is a sensorineural hearing loss, people tend to obtain hearing aids for treatment, since there is no medical treatment (like there may be for a conductive hearing loss).  However, the hearing aids is simply bringing in the environmental sounds and funneling it through a system that is not 'normal.'  [The hearing aids don't treat the hearing loss.]  Therefore, if there is distortion in the inner ear, the hearing aid will make environmental sounds louder, but will not 'fix' the distrotion.

Depending on your individual hearing acuity and difficulties understanding, a cochlear implant candidacy evaluation may help provide more information and options for clear speech.  You can find a cochlear implant Doctor of Audiology through Cochlear Americas, Med-El Corporation, and Advanced Bionic's website.  

Many others have provided excellent answers to which I want to add, hearing aids do not heal the damage that exists in our ears. 

As incredible as the technology has become, it still is an aid.  We are not actually healing the damaged hair cells in our ears, which at this point is still a dream in the field.  Also, when the problem has been allowed to deteriorate for years and years without help, the parts of the brain responsible for understanding speech atophy in a process called auditory deprivation.  Hearing aids don't heal that 100% either.   Studies consistently show most people wait an average of 7-10 years from the time they first notice hearing trouble to getting help, and the damage done by waiting cannot be undone.  Hearing aids can help reduce the impacts of hearing loss significantly, but it is just not the same as restoring our normal natural hearing before it was damaged and left untreated for years.

A good analagy would be asking the question, "I have been bedridden for 7-10 years.  Now I have a walker.  Why is it still difficult to walk?"  A walker assists us in walking but does not heal the damage and atrophy to our legs just like hearing aids assist us in hearing but do not heal the damage in our ears or eliminate the auditory deprivation.  Because of factors like the extent of the damage that exists and length of time that the problem was left untreated before help was received, there will always be some degree of distortion in our hearing and deficit in our understanding ability. 

The best results with hearing aids are achieved when the problem is caught early and helped soonest, but even that doesn't guarantee 100%, it just ensures our best chance to understand for the longest period of time.  Our brains are amazingly adaptable, so we can continue to improve our speech understanding for a long time once we do start wearing hearing aids, especially if hearing exercises are incorporated, but it is a process not an instant result.  Just like the bedridden for years person will not be able to jump up and run right away (or maybe ever) without a lot of therapy and effort, you will not be able to hear at your best right away with hearing aids without a lot of practice, patience and auditory rehabilitation.  The right hearing professional will guide you through this process, help you maintain realistic expectations, incorporate good communication skills and provide you with the auditory training you need in addition to the hearing devices themselves, to help you achieve the best results you are capable of achieving.  To get the best results, you have to put in the work as well as wear the devices.  This is especially true if you are wearing devices properly programmed, but still feel your results are unsatisfactory.  If you haven't already incorporated auditory rehabilitation exercises and made it a point to learn and practice good communication skills, those are things you can do to improve your speech understanding beyond what the hearing aids give you on their own.

Amplifying sounds with hearing aids are only one part of the equation. Many patients also struggle with speech discrimination. They may hear the sounds correctly but have lost the cognitive ability to understand them. This can improve over time and can be enhanced with some aural rehabilitation techniques. It's sometimes difficult to explain that hearing aids can restore lost sounds immediately but understanding those sounds happens over time. 

Understanding speech ( which we take for granted) is not a passive proces. It involves many higher level processing and interpretation. Hence if you look at hearing literature now hearing aid scientist are now looking into that aspect to be incorporated in hearing aids. There are many factors that could be influencing here. How long have you left your hearing loss untreated ( use it or loose it), degree of hearing loss , rehabilitation goals set by you and your hearing health professional.... If you are not happy with the outcome you need to go back to your Audiologist and get the settings looked at... 

Raji Parangad

'My Audiologist'

Most people do not realize that hearing and understanding are two different things!  Hearing is natural for most of us, we are born with hearing.  Understanding, we have to learn through languages.  Ex: baby born in US, raised in Mexico can only understand Spanish if her parents do not speak English to her at home!  So with hearing loss, people start to loose the the footprints of certain sounds over time.  The longer they wait to be treated, the more forgetfull of the sounds they will get.  As a result, when they finally got fitted with hearing aids, they hear sounds that their brains are no longer familliar with and that makes it hard to understand certain words.  The best exercise to do in this case is to wear your hearing aid faithfully to acclimate to the sound, and read OUT LOUD to yourself, with the hearing aids in your ears so that you have a visual-auditory correlation.  That would help speed up the process of getting to re-recognize words. The best scenario would be to get help as soon as possible with your hearing problems.

Hope this helps.

There are basically three parts to your hearing loss. 1) How loud we have to make each pitch for your ears to hear it, 2) How well you understand the sound (words) once the loudness correction is made, and 3) How well you understand words once the loudness correction is made, but in background noise like in a restaurant.  Everyone's score on the #2 and #3 parts are different and this score determines how well you should understand words in quiet and in background noise.  Once those scores are determined, then the best hearing aid recommendation is made for you.  If for example a person has a score of 60% on the #2 part, I let them know that AT BEST they can understand 60% of the words they hear in quiet and when they are paying attention.  This is based on the damaged auditory system and cannot be fixed or bypassed.  Also, if you have a poor score on the #3 part, then maybe a premium hearing aid would be the only one to reduce background noise enough that you could understand the words in that type of situation.

Also using all hearing aid brands, I have also found that not every brand works for every person.  I explain it like blood pressure medication. The doctor will say "here try this one," then have you return later to evaluate its effectiveness. If one brand doesn't work well for you, you may need to try a different brand.

In addition, you have to give it time.  The auditory part of the brain responsible for the frequencies where you have hearing loss has not been used like it should.  You have to give the brain time to relearn how to correctly interpret the sound.  I tell my patients you will perform better immediately, but will do even better after a week of wearing the hearing aids, then better at a month of wearing the hearing aids.

Finally, sometimes it depends on the person fitting the hearing aids.  If you have not haad success and do not have an explanation (like performing poorly on one of the above mentioned tests), then you may want to go to someone else.  

Some people have experienced damage to the hearing nerve which does not allow them to hear words clearly.   During a hearing aid evaluation an audiologist needs to know first, how loud sounds need to be before the patient hears them and secondly, how clearly does the patient understand words.   (Of course there is more involved in the audiology report but for hearing aid purposes those two factors are most important.) Some patients have very poor word discrimination and when given a list of 25 to 50 word they may be able to repeat only get 30% or less.   This can not be corrected by the hearing aid. Hearing aids can make speech louder but not always clearer for those people who suffer from poor word discrimination.  

Hearing aids should make it easier for you to understand words if they are programmed correctly but a patient's word discrimination score may still make it difficult- even with a hearing aid.  The best advise I can give to any patient is to not put off getting hearing aids because your word discimnation score could possibly decrease with time with untreated hearing loss.  Also, if you have hearing aids please wear them all day, every day... you will get better results.

Speech understanding is a complex process. During your audiological evaluation you may have testing done that can assess how you comprehend speech in both quiet and noisy situations. Your audiogram may look the same as another person's, but the way you each individually comprehend conversational speech might be different. A combination of these tests and learning about your specific listening environments will help your audiologist determine the best device for you. The more information you provide your audiologist about how you hear conversational speech will help in the programming process. It is important to make sure that your hearing aid not only enhances volume, but clarity as well.