Foundations of Cognitive Psychology: Interview with Daniel J. Levitin PhD
Douglas L. Beck, AuD, speaks with Dr. Levitin about his new book, Foundations of Cognitive Psychology and his previously authored book, This Is Your Brain on Music-The Science of a Human Obsession.
Academy: Good Morning, Dan. It’s always a pleasure speaking with you!
Levitin: Hi, Doug. Nice to speak with you again too.
Academy: Thanks. Let me start by congratulating you on your new book, Foundations of Cognitive Psychology, Core Readings, Second Edition. Although I don’t usually read too many books on cognitive psych, I really enjoyed this one, as it overlaps so much with what’s happening in contemporary audiology with regard to perception and cognition. And in fact, I suspect the first edition of the new book, This Is Your Brain on Music, actually serves as the foundation from which you wrote.
Levitin: Yes, exactly right. The big secret about my first book (which will no longer be a secret!) is that a lot of the ideas and preliminary text from it came from the first edition of Foundations of Cognitive Psychology. In fact, many of the lectures I’d been giving for some 10 years or so at McGill University and at Berkeley and Stanford came from that first book, and then topics such as categorization and perception from those early days and early publications become more palatable for the general audience via This Is Your Brain on Music.
Academy: Yes, I can see how that evolved and it’s interesting to see it in the context of a continuing and developing work. And oddly enough, you’ve got a new publisher for the second edition?
Levitin: Yes, that’s a little unusual. I actually went to MIT Press and suggested we should do an update of the first edition, but they weren’t interested. So I suggested it to Penguin, they were interested, we agreed on which sections to update, co-authors, publication schedules, and we ran with it.
Academy: Hmmm. Reminds of the guy at Decca Records in the early 1960s who rejected the Beatles saying something like “Guitar bands are on the way out….”
Levitin: I know that quote. We’ll see how it turns out.
Academy: Absolutely. So to me as an audiologist, the most interesting issue is how the ear merely serves as a conduit, whereas sound perception and listening occurs within the brain—and listening is a cognitive skill that develops over time, so it’s very reasonable to presume cognition serves as the basis for hearing and listening. So in particular, I was hoping you would address the old “inverted spectrum” issue, which is one of the opening topics in your new book. The core concern with regard to sensory perception, and I’ll form the question with specific regard to vision, how can we know that if you and I look at a car and we both agree it’s blue, can we be sure you and I are each perceiving the same color?
Levitin: Interesting question, and of course it’s a fundamental question that likely goes back to the days of Plato and Aristotle. Actually, the reason the book starts with this query is the point that many of the “previously unanswerable” questions can now be addressed through proper experimentation or through neuroscience and other modern approaches….and so the Inverted Spectrum argument helps us understand the question and the approach to solving it.
In brief, the inverted spectrum argument states that your and my color experience are exactly the same, except perhaps for being spectrally inverted. That is, maybe when you look at the sky, your internal experience is the same as when I look at a tomato. Your blue is my red—this is spectral inversion. How do we ever sort this out? But let’s talk about this in terms of your and my favorite sense—audition. If I play a chord on the piano or guitar, how do we know you and I perceive it the same?
Academy: Okay, that does hit closer to home. And of course, I cannot prove we actually hear anything the same. In fact, I can easily argue for that not being the case when one considers how dramatically the auditory nervous system changes as it matures from birth to teen years, and how we would be very hard-pressed to find any two people with exactly the same hearing thresholds across the spectrum, and how the ear canals physically change along with the ear canal peak resonances and on and on.
Levitin: Right—and so the point is you have all of those issues you just mentioned which impact the sensory signal, the “bottom-up” signal per se, and then add to that the cognitive awareness and integration of the sound signal based on the hundreds of thousands—or more likely hundreds of millions—of neurons that impact cognition as a “top-down” phenomenon—and it’s a wonder we can all create, learn, and process the same language!
And so, cognition actually forms perception. Again, with respect to hearing, the outer, middle and inner ear are of course very important—but as you said, they serve as the conduit. Hearing and listening occurs in the cortex—and we’re learning more about that every day. For example, with regard to psychoacoustics and tuning curves, just through sheer concentration, attention and will, I can affect the tuning curves of the receptors in the ear itself. If you tell me to listen for a 1000 Hz tone embedded in noise and other auditory distractors, and that every time I correctly detect it I’ll get hundred dollars, those tuning curves will become sharper and more accurate—that is, the percept of bottom-up auditory cues can be altered through top-down processes.
Academy: Fascinating information. I think audiologists are just really starting to think about the impact and influence of top-down processes on bottom-up stimuli. Dan, one of favorite chapters in the new book is Al Bregman’s chapter (Chapter 7) titled “The Auditory Scene.” Would you please share some thoughts on that?
Levitin: Sure. I should mention first that Dr. Bregman was actually my mentor and he recruited me to my position here at McGill, and although he’s officially retired, he still contributes significantly. In fact, he’s got some fascinating demonstrations available on the Internet and he has written a fascinating book which is still available at MIT Press.
So basically, he started with the Gestalt principles of vision and searched to find auditory analogs. He states we organize our auditory world in terms of similarities in pitch, timbre, rhythm, timing and spatial location, and then he queries what does it mean to be similar in pitch, timbre etc? Auditory scene analysis has been his 30- or 40-year research project to document systematically factors that allow sounds “to go together.”
Bregman teaches us that nobody listens to oboe overtones during a classical music concert—although we all perceive them. And the reason that happens is the overtones stop and start at the same time, and the onset time matters a great deal to give you the sense of a single instrument. Bach, in his sonatas and other compositions, often had a single instrument rapidly playing notes in different octaves, thus giving the image of two instruments; one playing the high notes, the other playing the low notes. That is, the high notes and the low notes were so far apart that it sounds like two flutes! Bach probably didn’t know why it occurred, although he knew that it occurred. Bregman tells us why.
Bregman addressed the disparity of the highs ands lows and how the brain assumes via top-down processing that no natural object could traverse “pitch space” so rapidly, so the top-down cognitive percept is: it must be two instruments. And of course, this holds true not just for spectral components and analysis, but for pitch, timbre, rhythm, timing and spatial location, too. Similarly, if we hear a “chirp” and a “growl,” we assume because they are so different, they originate from two separate sound sources, as we did not evolve in a world where any single animal makes both growls and chirps!
Academy: And of course, we pay much more cognitive attention to the growl as it’s so much more threatening, potentially triggering the “fight or flight” response.
Levitin: Right, and so when things are very far apart in terms of pitch, loudness, timing etc., they are probably not the same thing and this a very important analysis for survival.
Academy: Excellent point. I’d like to get your thoughts on the issue of “Attention,” which is the topic and title of Ashcraft and Klein’s chapter (Chapter 15). The reason I ask is I’ve been thinking attention is the key to so many educational and processing issues; auditory processing, auditory processing disorders, attention deficit disorders, attention deficit hyperactivity disorders, dyslexia, spelling and reading skills and more—and it seems to me that quite often, these maladies terrifically overlap and the exact diagnosis may have more to do with the professional’s area of expertise, more so than the exact nature of the disorder.
For example, David Strayer, a psychology professor at the University of Utah, was quoted in the NY times in August 2010, (http://www.nytimes.com/2010/08/16/technology/16brain.html?_r=1&pagewanted=all)with what has since become one of my favorite quotes, “Attention is the holy grail.”
Levitin: Absolutely. I read that, too, and he was exactly right. It’s got a lot to do with the top-down processes we just spoke of. Each of us sees the world in terms that are comfortable and familiar to our brains, which isn’t good or bad, but it’s the way we process what’s around us. So you, as a doctor of audiology may see an eight-year-old child with certain attributes and behaviors and diagnose him as having an auditory processing disorder, but the pediatrician seeing the same child may very well diagnose attention deficit hyperactivity disorder, and the speech-language pathologist seeing the same child may say he has a receptive language disorder—and so all these professionals are viewing the child through the professional lens that’s most familiar to each of them. In other words, when you’re a hammer, everything looks like a nail. And so Ashcraft and Klein’s chapter addresses attention as a limited capacity resource, and simply when people try to multi-task, such as texting and driving, their attention is divided and so they cannot do either task maximally.
Academy: In my current presentations, I use data from the recent National Highway and Traffic Safety Administration report, which states that 80 percent of all motor vehicle crashes involve a distraction within three seconds of impact.
Levitin: Right, that’s the point. When you pay attention to one thing, it is necessarily at the expense of paying attention to something else. In other words, there are some low-level functions that can be achieved effectively while multi-tasking, but there are many things one cannot do safely or competently while multi-tasking.
One example that rings true for many people is when you’re learning to drive a stick-shift for the first time, it commands all your attention, and even then you’re very likely going to stall out and lurch ahead while learning to integrate the tasks required to shift smoothly. However, after lots of practice, you can listen to the radio and converse with a passenger easily and safely and sometimes driving that stick shift becomes so well learned and practiced that you might forget which route you took to work—it was almost an automatic function. You were engaged enough to not crash the car, but not paying so much attention to the process—because your brain knew the process and so it commanded less conscious attention, and driving becomes more or less an automatic process. But then if you put significant attention into texting, or a phone call or a distraction, you’re taxing your limited capacity resource (attention) and a crash becomes much more likely.
Academy: Lastly, I’d like you to discuss the development of expertise and the refinement of perception.
Levitin: Sure, well the thing is, the more expertise you have, the more refined your perception becomes. Doug, do you recall when we spoke a year or two ago about how one needs to practice music, baseball, painting – whatever – for at least 10,000 hours to become an expert?
Academy: Yes. And I actually recall your discussion on the same subject (page 197) within This Is Your Brain on Music.
Levitin: Well, many music lovers cannot tell the difference between a viola and a violin, or a cello and a bass, although they may absolutely love music. But a real expert violinist can tell the difference, and they can probably even tell which manufacturer made the violin and maybe the type of strings or bow being used. I suspect you can tell the difference in the sound of your Martin acoustic guitar and your Epiphone Casino electric—and this is pretty common among musicians and other people with expertise in their area.
You know, some really good house painters can walk into your house and say, “Oh, I see you’ve got eggshell finish in your kitchen.” And a really, really good painter can probably tell the difference between Sherwin Williams and Benjamin Moore paints. Another example might be a photographer who walks into a room and can tell you the type of lens or f-stop they’ll need for a portrait based on the lighting in the room. Or consider a chef who tastes a new soup or other creation and can instantly tell you to a first degree of approximation what the ingredients are. So indeed, perception changes and can be refined as expertise emerges, and this carries through to speech perception, attention, music, and so much more.
Academy: Dan, it’s always fascinating speaking with you. I totally enjoyed the new book and I have to agree that cognition is the very foundation of listening, and the book reveals a plethora of new and important information. I wish you all the best with the book and look forward to the next time we speak.
Levitin: Thanks, Doug. I appreciate your time and interest in my work.
Dan Levitin, PhD, is the author of Foundations of Cognitive Psychology and This Is Your Brain on Music-The Science of a Human Obsession.
Douglas L. Beck, AuD, Board Certified Audiologist, is the content Web editor for the American Academy of Audiology.