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Interview with Teri James Bellis Ph.D., Audiologist, Author of 'When the Brain Can't Hear: Unravelling The Mystery of APD'

Teri James Bellis, PhD

March 19, 2002

AO/Beck: Hi Teri. It is fantastic to spend time with you again!

Bellis: Hi Doug. It's great to be here.

AO/Beck: For the readers who might not be familiar with your work on CAP/APD, I wonder if we can review a little about your education and your professional background before we get into the new book and central auditory processing disorders/ auditory processing disorders (CAP/APD), if that's OK?

Bellis: Absolutely. I got my master's degree at the University of California at Santa Barbara (UCSB) in 1985. I became interested in audiology because I had grown up with a deaf brother. In particular, I spent a lot of time at UCSB working and studying electrophysiology related to hearing and brain function. After graduation, I went back to Colorado and I was working with multi-modality evoked potentials, and that's when I had my car accident. I was completely unable to work for about 6 months. I had a variety of physical injuries, and had also suffered some severe visual processing problems. So, when I finally got back to work, I found that I was no longer able to detect the tiny, subtle changes that we look for on the screens and monitors in surgery. Of course Doug, you've probably done more intraoperative monitoring than most people, you know how hard it is to look for tiny electrical changes for long periods of time. Anyway, after the car accident, I just couldn't do it. My eyes and my brain couldn't work together to find what I was looking for.

AO/Beck: What did you do then?

Bellis: I couldn't work in the OR anymore, so I moved on. I started working in educational audiology and started focusing more on CAP. In 1994, I was lucky enough to complete a research fellowship in neuroaudiology with Frank Musiek at Dartmouth. Then in 1996, after my first book on CAPD was published, I enrolled at Northwestern University to earn my doctorate with an emphasis in language and cognition, and I completed my doctorate in 1999.

AO/Beck: Teri, I don't want to reveal all of the book's secrets, but as you mentioned above, you had a closed head injury car accident and that impacted the way your own brain worked.

Bellis: Yes, that's correct. I had a lot of cognitive problems that were the result of damage to the right hemisphere of my brain. Most of these problems were in other areas, but some of them affected my auditory skills, too. You know, as a profession we audiologists have been terrifically concerned with left hemisphere issues for a long time, which makes sense as that's where the primary language centers are. But we really hadn't done much with right hemisphere issues. I think my injury was probably one of the first documented cases that I, personally, had examined in depth. It never occurred to me that I had an APD at all because my own symptoms were not textbook symptoms of APD. I had no problems in noise, no problems understanding individual words (speech recognition), no distractability, but following the accident I noted that everyone was speaking to me in odd tones of voice. I also thought people were being sarcastic, or perhaps abrupt with me. I thought everyone had a mean tone of voice - and this was even true for my own family members. I also found myself not getting jokes and puns. It was really very unusual and disconcerting. It was also very subtle, especially compared to my other difficulties, and it was more like the intent behind the words had changed.

AO/Beck: And I have to tell you, that as a clinician, if you came to me and had recognized the symptoms well enough to describe them, I would have had no idea how to test for that, and frankly, even if I could've come up with a test, I would have no idea what to do with those findings, except perhaps a psych referral, had that seemed appropriate at the time.

Bellis: Of course to make it worse, when I spoke to my doctor about it, he said You've been through a traumatic car accident, and you need to understand that it takes a long time to heal, all of this is understandable and we see this in post-traumatic concussion syndrome regularly. And it drove me nuts because I knew that my auditory perception was real to me.

AO/Beck: So then, how did you ever put all this together and arrive at the conclusion that this was indeed a sign or symptom of an auditory processing disorder (APD)?

Bellis: Well, one day I was demonstrating auditory electrophysiology for an intern, and we were using me as a test subject. So he hooked me up with the wires and the computers and when we were done, I was reviewing the results, and I had a 75% reduction in the cortical response of my right side. So of course I thought...he did something wrong, he's an intern we redid the test - same result. Then all of a sudden, I realized the auto accident may have changed the way my brain processed auditory information I did the tonal pattern tests next, and I couldn't do the test at all. I was simply amazed at what I couldn't do. Then we did dichotic digits and competing sentences and again, the left ear was way down.

AO/Beck: So in simple terms, your left ear result was far worse than it should've been, and in fact because you had tested yourself hundred's of times on these tests throughout graduate school, you knew you previously had normal results!

Bellis: Yes, that's correct.

The results of these tests were like a light bulb going off, and it confirmed that something was indeed wrong in my auditory processing. That got me to pay attention to the subtleties and the punchlines, and then once I knew where the problem was, I was able to work on it, and improve it. Anyway, this information along with data from other people with right-hemisphere damage allowed us to change our model of APD to include those problems that occur in the right hemisphere of the brain. So there are several different types of APD, and they can look very different from one another.

AO/Beck: You know another thing this brings up is the issue of test-retest. Many people think that you can only give these tests a time or two and then the patient has too much familiarity with them for the results to maintain validity. But in fact, even though you had given the tests hundreds of times, and been involved with test design and administration, the tests were able to catch your errors, and you weren't at any advantage at all based on test familiarity.

Bellis: Yes, I've though about that too. It is really amazing and frustrating...even though I've administered and even taken these tests so many times over the years, and know exactly what is supposed to come next or what the stimuli are supposed to sound like, I just can't do them anymore. On some tests, I could tell you the right answer based on memory, but I can't actually hear it even with a great deal of familiarity! It's given me an opportunity to really see first-hand how these tests sound to someone with an APD.

AO/Beck: Well Teri, you have an amazing history and we can explore that for a long time, but as you guys were nice enough to send me the book, and as I've actually read the whole thing, we oughtta talk a little about the book too. So let me change focus here a little. The book is published by Pocket Books, and they're a division of Simon and Schuster. The title is When the Brain Can't Hear - Unravelling the Mystery of Auditory Processing Disorders.

This book is unique in many aspects. First of all, it's written by you, and you are indeed one of our profession's few expert and prolific authors on this topic. Your previous book was really more of an audiologist's text on APD, wheras the new book is for doctors, audiologists, speech-language pathologists, teachers, and importantly for the moms and the dads too.

Of course within the professional arena, you have also published many papers and given many presentations on APD. In fact, you wrote a paper a year or two ago which was co-authored by my wife for Audiology Online, and we'll hyperlink to that one at the end of this interview for those interested in the topic.

Bellis: Thanks, that's a nice overview. Yes, the book was written for a multiplicity of professionals, and importantly, it's for the parents of kids with APD or people with APD themselves. I talk about how APD looks in infants, children, and adults, how it's diagnosed, and how we can treat it, using lots of case studies and including the latest clinical advances.

AO/Beck: One of the things you establish early in the book is that although there are a number of things that can co-exist, APD really is strictly focused on things that require an auditory input. What do you mean by that?

Bellis: We have to concede that APD can co-exist with many things, the most common being attention deficit hyperactivity disorder (AD/HD) or language disorders, but those things are not APD. When we talk about APD, we must limit that to problems in the auditory system, itself.

AO/Beck: So it's an input to the brain issue?

Bellis: Right. Certainly, things like attention, language and cognition affect how we are able to use what we hear, but that's not the same as an auditory input problem. Those of us who specialize in APD need to be able to maximally separate out those other issues, so we can diagnose and treat APD. It's a hard thing to separate out top-down from bottom-up issues, but we have to do the best we can to see if the test results are consistent with APD, or some other non-auditory based situation. Not every language or learning problem is APD. Again, all these things can co-exist, and they may masquerade as each other. So basically it boils down to the diagnostic ability of the professionals. Do they know about APD, are they trained and experienced and can they administer the right tests and interpret them correctly while, at the same time, working with other professionals to arrive at the big picture ? These are very important considerations.

AO/Beck: Teri, it's really been a pleasure to work with you, and I know we can discuss this for hours on end. But I really should let you go. Nonetheless, before I do, what are the take home messages for the reader?

Bellis: There are three primary messages I like to focus on. The first is that APD requires a diagnosis by an audiologist. It simply cannot be diagnosed by a checklist of symptoms,a dn of course, the diagnosis is critical to appropriate and successful managament.

The second message is that no one treatment is a cure all. It really doesn't matter if you know others with the same symptoms. You can have identical signs and symptoms, but the treatment plan may still need to vary - because each patient, and each patietn's situation is different. The treatment plan needs to be appropriate to the symptoms, and to the individual! The last big take home message is hetereogeniety! APDs look very different from person tp person, and APDs can co-exist with other problems, that are not APD.

If your child, or spouse, or if you have APD we have some excellent therapies that work, as well as very good ways to help you learn to live and function in spite of the disorder. For those diagnosed with APD there are options and alternatives. Bottom line, if there is a suspicion of APD - get tested. But remember, if you or your child have listening, language, or learning problems, you should begin with hearing, language, and learning testing. APD should not be a starting point in the diagnostic process, and not all listening, language, or learning problems are due to APD.

AO/Beck: OK, I'll go with all of that! Teri, for folks who wanna get a copy of the new book,what is the easiest way?

Bellis: : The book is available at bookstores nationwide, as well as via,, and other online booksellers. Or you can contact the publisher (Pocket Books/Simon & Schuster) directly at

AO/Beck: ThanksTeri. It really has been a pleasure. I wish you all the best and I anticipte seeing the book on the NY Times bestseller list pretty soon!

Bellis: Thanks Doug. Good luck to you and to Audiology Online too.

Additional References:

Central Auditory Processing in Clinical Practice. By Teri James Bellis, Ph. D., Assistant Professor, University of South Dakota and Barbara Roe Beck M.A., Instructor, Saint Louis University
Explore 35+ courses in partnership with Salus University

Teri James Bellis, PhD

associate professor of audiology and Chair of the Department of Communication Disorders at The University of South Dakota

Teri James Bellis, Ph.D. - Author of When the Brain Can’t Hear: Unraveling the Mystery of Auditory Processing Disorder (2002, Pocket Books), Dr. Bellis has been involved in the development, management, and implementation of audiologic and neurodiagnostic programs in clinical and educational settings for the past 19 years, including multimodality evoked potentials programs and central auditory processing service delivery programs. She received her doctorate in Audiology with specialty certification in Language and Cognition from Northwestern University. An internationally recognized expert in APD, she has lectured and published widely on the subject of central auditory processing assessment and treatment. Dr. Bellis is associate professor of audiology and Chair of the Department of Communication Disorders at The University of South Dakota. The second edition of her bestselling textbook: Assessment and Management of Central Auditory Processing Disorders in the Educational Setting: From Science to Practice is now available from Delmar Thomson Learning.

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