In this podcast episode, Melanie Hamilton-Basich of Rehab Management and Physical Therapy Products talks with Mike Studer, PT, DPT, MHS, NCS, CEEAA, CWT, CSST, FAPTA, and president of Northwest Rehabilitation Associates Inc, about the use of dual task testing and training to both assess clients who have experienced a concussion and to facilitate these athletes’ recovery so they can get back to the sport they love.  

Podcast Transcript

Melanie Hamilton-Basich:
This is Melanie Hamilton-Basich, chief editor of Rehab Management and Physical Therapy Products. For today’s episode. I’m happy to be here with Mike Studer, who has a doctorate in physical therapy and a lot of other degrees and certifications and is the president of Northwest Rehabilitation Associates Inc. We will be discussing the use of dual task testing and training to both assess clients who have experienced a concussion and to facilitate these athletes’ recovery so they can get back to the sport they love. Mike, I understand that you’ve been passionate about dual task testing and training for many years. Can you explain what this is and why dual task testing and training is so important for physical therapists to use in readying injured athletes to get back to their sport after a concussion?

Mike Studer:
Absolutely. Melanie, I’m happy to talk about this and I’ll start off by saying yes, I’m very passionate about dual tasking. And I’m passionate about it really across the spectrum of age, as well as function because it helps us to truly live out and maximize what our motor control abilities are when we are tolerant of handling distractions in our world and environment. Specific to today’s conversation about athletes that have sustained a concussion and their efforts to return back to their chosen sports or multi-sport, we understand it’s so important. Because when an athlete has been concussed their abilities to be able to integrate and synthesize sensory information that’s coming in at high speed and combining that with motor control and physical actions that are ballistic in nature, also high speed. We need to optimize reaction processing.

Mike Studer:
We need to optimize decision making so that athlete is not only successful in their sport, but they’re also safe to themselves, don’t endure another concussion because they made a poor decision, didn’t see an opponent or a teammate, but that they are also safe to the other players on that field, court or pitch. So for those reasons, dual passing is important for the proficiency and the safety of the athlete and those around them to optimize motor control, accuracy, performance and to truly make the best decisions that this athlete’s body and mind can combine together.

Melanie Hamilton-Basich:
I understand that automaticity is really important here. Can you explain what automaticity is?

Mike Studer:
Yeah. I’m happy to. Automaticity is really that underlying skill that is developed when an individual has proficiency in a movement. And again, in today’s discussion, we’re talking about sports and athletics. And what we really understand as an overview is the definition of automaticity is the degree at which someone can move without paying attention to the particulars or the details of that movement. So when I’m out dribbling a soccer ball, kicking it forward with my feet and moving down the field, I shouldn’t have to think about what aspect of my foot I’m going to guide or glide that ball forward with. Similarly, if I’m shooting a free throw and there’s pressure involved in the game context, the game is on the line and my free throw is going to make a difference, I want to have a high degree of automaticity.

Mike Studer:
So automatic movements that are very procedural in nature so that I don’t have to concentrate about or dictate the degree of wrist extension I have to have my wrist cock back at to be able to release the free throw in the manner that’s going to make me most successful. Automaticity, the ability to be able to move without paying attention toward the details of the movement. That comes with experience but interestingly enough, Melanie, this actually is only formidably developed when athletes have been exposed to dual task environments, pushing their motor control down into centers that we call procedural memories. So we actually store general senses of how this movement’s supposed to occur so that our conscious entities within the brain, the motor cortex, doesn’t have to say, hey, make your elbow this angle, and your wrist this angle, and your shoulder this angle and that’s how it’s going to work out. We need automaticity, a degree of automatics.

Melanie Hamilton-Basich:
So to get to that point, how do you dose dual tasked delivery?

Mike Studer:
Wow, that is certainly a developing science and one that I’m very happy to speak to. And one that I’m very happy to also contribute to. So dual task dosage is an imperfect science at this point. And what it appears as though we are coalescing around is understanding that really everything in rehabilitation and athletic training needs to be delivered with a consideration of personalization, right? So one of the first things that we think about in dual task dosage is, what are the things that engage this person? And obviously in today’s conversation, it lends itself extremely well to making that conversation occur around the sport that we’re talking about. So one of the things that we dose dual task with is specificity. We want to make sure that our dosage and delivery of a distraction is very sport-specific. So we start with that.

Mike Studer:
And in addition to that, we have to give consideration toward a patient interview. What engages you? What can I offer in terms of a conversation that we’re having? Or objects to look at, or numbers and facts and figures to manipulate in your mind, what engages you and what disengages you? I don’t like math. I don’t want to do that. So we always want to consider the person as truly the overall show. Then the specifics of dosage have three main considerations for our audience today. And those three very clearly are novelty, pressure and volume. So you think about novelty, the dosage of a dual task becomes increased if I’ve given use something that in movement or in cognition is novel for you. Something that you’ve not experienced before is always going to be a higher degree of difficulty. So we use familiarity if we want to lower the dosage.

Mike Studer:
Then I said pressure, right? Well, that’s going to be pretty obvious to anyone that we can dose based on pressure. And if we think about that in a sports-specific manner, we think about, well, being able to get the shot off before the clock expires. We think about the time that a pitcher has to deliver between pitches. We think about pressure also in physical natures with more people guarding you than would normally be the case. We think about maybe even pressure with consideration of game context, the score’s on the line as I referenced earlier. And then finally, we can even think about pressure with regard to the viability of your position on the team. Could you lose your starting position? Or even trash talk coming in from opponents. So we think about pressure being something that if we don’t expose our athlete to that, the athlete will not have the capacity developed such that when they’re on the field, they will not be able to tolerate it.

Mike Studer:
And then the final thing that I talked about was volume, and I think volume is also very intuitive here. So volume is thought about in several different contexts. It can be the duration, how long am I going to be out there before there’s a time out or a break in the play? Volume can also mean, I’m going to send you onto the field and I want you to remember these are the three plays that I need you to relay to the quarterback so that he can actually give them back to the team in the huddle. So that’s volume of information we’re going to do red 32 cut on two, and we’re going to do diagonal blue, blue, right.

Mike Studer:
You’ve got to remember volumes of information. That’s be one thing that has to be held in processing in working memory. And then finally volume can also come in the form of physical, just like the other two novelty and pressure did. And those could be physical loads. I’m using a weight vest, or I have to push a sled, or the length of a field or a court to cover. So when we’re dual tasking, we think about both attributes, the physical and the cognitive, and we dual task in our dosage based on novelty, pressure and volume.

Melanie Hamilton-Basich:
And how is dual task capacity evaluated?

Mike Studer:
Wow. And that is another consideration that is a science that is developing. So one of the initial iterations of dual tasking was basically just a stops walking while talking test. And we know that’s very far beneath, it’s got a very low floor here because basically anyone’s going to be able to be functional if they have athletic capacity to be able to walk and talk, right? So as our body of knowledge developed, we began to actually combine tests that could be measured such as a walking test, that many of us know such as the timed up and go test. And then we began to overlay cognitive tasks on top of that, the most well known and well studied would be developed by Anne Shumway-Cook, the cognitive timed up and go. And that still stands the test of time today, wherein an individual is asked to subtract three away from the number that the examiner gives to the individual while performing the timed up and go test.

Mike Studer:
So that means literally this I’m going to measure you in your timed up and go, stand up, walk three meters, turn around, come back, sit down in the chair. Now I have your physical only performance. Now I’m going to have you sit down in that chair, don’t stand up, wait, and I’m going to give you the mathematical operation. I’m going to say 98 and then you are going to give me numbers that follow 98 were you to subtract three consecutively from that you’ll say 95, 92, 89, 86, et cetera. So I’ll confirm that you’re capable of doing the cognitive by itself. We call that cognitive only. In the most sophisticated expression of this, I would also measure your capacity to do that. Then I combine them in a dual task fashion. And I say, when I give you the number, then I want you to begin the timed up and go test on your mark, get set 89.

Mike Studer:
And now you say 86, 83, 80, while you’re doing the timed up and go, and I measure both attributes. How many times did you accurately count backwards by three? And what was the time required for your timed up and go? Now I have something that offers me to be able to compare my physical only, my cognitive only to my dual task and we create something that all the dual task cost. Which is basically a very unsophisticated, very simple mathematical equation that gives me a percentage of the difference between my dual task performance and my single task performances. Now, the last thing I should say about this Melanie, is that dual task is being measured now in many other fashions by combining physical single performance with other cognitive standardized and developing tests. So that could be consideration of something like we call the Brooks spatial memory test.

Mike Studer:
And if you can imagine yourself Melanie, now out on a football field and you’re at one end zone, and I’m asking you to run to the other end of the field and I measure your 100 yard dash. Okay? And now I could do that again to see if you’re ready to return to sport. And I begin to give you the Brook spatial memory task. And I say to you, there’s a one in the bottom left hand corner of this nine box that you’re thinking about, nine box matrix like a Sudoku puzzle, if you will. And I tell you there’s a seven in the middle, and I tell you there’s a three in the bottom right. And by the time you get to the end, you’ve got to give back to me what that box looks like. Oh, you told me there was one in bottom left, seven in the middle, three in the bottom right.

Mike Studer:
And then I gave you all the rest of the other nine. So that would be one way to measure. And there’s so many other ways to measure that are developing now. They’re fascinating ways that can give us the opportunity to not only cognitively dual task, but also look at the other modalities that you and I are going to talk about in a moment. So it’s a fascinating, developing field that has to just contain a couple of essential elements, a physical only that is discreet from a cognitive only. And we’ll talk about what those distractors could be. And then the combination of the two.

Melanie Hamilton-Basich:
As you were just saying, I would like to know what are the four modes of distraction?

Mike Studer:
Yeah. So far we’ve spoken primarily to cognitive modes of distractions. Those are easiest to understand and easiest to measure for the most part, but when we’re delivering dual task rehabilitation and to some degree testing, sophistication is developing on this, we need to consider that there is also visual distractions that players have to endure, right? So you think about an NBA basketball game where the player’s at the free throw line, so this would be WNBA now, and the opponents of her team have a fan base that are basically waving signs behind that backboard and trying to get you to be distracted and miss your free throw, right? So that’d be a visual distraction. Then in the same context, we could have auditory distractions, hey, you’re no good, you missed your last free throw. Hey, how many points did you score last game?

Mike Studer:
So auditory distractions, again, intended to cause the opponent in that example to concentrate on something other than their motor performance. And then finally we have the example of a manual distraction. And so that would be a very simple way of thinking about a manual distraction would be, I have to be able to… Oh gosh, there’s a famous story where a person did a full triathlon while juggling two or three tennis balls the entire time. So you can imagine juggling three tennis balls while cycling means you don’t have your hands on the bike. He did the same while he was running and he juggled two while he was swimming basically a backstroke on the swim. So that would be the easiest and most, I guess, jovial way of being able to relay to you a manual distraction, doing something with your hands or feet that is separate from the translation of your body that’s the primary task. So we have four cognitive, visual, auditory and manual subtypes of distractions.

Melanie Hamilton-Basich:
At what point along the stages of rehabilitation should dual task training be introduced, do you think?

Mike Studer:
Yeah, that’s a really great question. And there is some evidence here and our colleagues, including Karen McCullough, Rob Landel, and many other colleagues, have done an exceptional job in creating really a clinical pathway for concussion and understanding how to pull together the best evidence in dual tasking. And we know there’s basically five stages of recovery Melanie, and we know basically that stage one is a little bit of rest in the first 48 hours, a little bit of light activity ensuing, right concomitant with that, something that does not provoke symptoms. So we call that a sub-symptom threshold of performance. And we move into stage two where we can increase the physical and exposure to light, sounds, et cetera. Stage three is the answer that you’re looking for there. That’s the first time that we really start to give an individual a little bit more on field but non-contact exposure and performance, and we can start to integrate and reintegrate some dual task considerations.

Mike Studer:
And again, just like we consider the physical attributes, we want it to be sub-symptom threshold. We also don’t want to deliver so much volume of dual task or novelty of dual task or pressure of dual task that it causes an incursion of symptoms higher than three points where the individual started. So the answer is stage three, where we’re increasing the physical demands and the cognitive demands. And we begin to just gently introduce dual tasking at that point. There’s so much that’s undeveloped in this world of dual tasking that I think people get a little bit too caught up in, well, I have to give them subtraction, or I have to have them spell words backwards. And we could talk a little bit about that if there’s time to really flush out the understanding of what could practically be delivered in return to sport as well.

Melanie Hamilton-Basich:
Can you share how dual task fitness training can be used as a preventative and how that’s different from how you would apply it for rehabilitation?

Mike Studer:
Wow, that question helps me answer what I had left on the table there to consider and really pushes forward to complete our efforts here today. Because in reality, an individual’s tolerance for dual task is only as proficient as their experience and exposure. Very similar to strength training, resistance training, where you will develop the ability to be able to recruit muscle fibers and develop skeletal muscle tension and the ability to produce force. Your ability to handle distraction is something that can be trained and something that can be untrained. So when we want to have an athlete to be very resilient, we want them to have a degree of redundancy in their dual task capacities.

Mike Studer:
So we want to even load them up a little bit with more pressure, more novelty, more volume than they’re likely to face in the game and in the sport so that when they get there, their automaticity is highest. But if they get injured, they’ve got a degree of reserve, of preserve, of redundancy that is available for them to be able to rehabilitate from. The best analogies are these, okay? First of all, people with Alzheimer’s disease that are very, very highly educated, oftentimes take longer to get diagnosed because the cognitive errors that they make from the very high level that they’re at are a lot of times harder to detect. So they’ve got so much redundancy they can afford to lose some cognitive faculties and capacities.

Mike Studer:
The same can be said for dual task to build up redundancies. The other thing is, imagine a married couple that have raised a busy family for the last 15, 17 years, and now they have no kids in the household. And over the next three to four years of them being empty nest parents, these two individuals become less tolerant of noises and people and interactions and movement. And now when the kids come home to visit, they become overwhelmed and they become more easily just fatigued. So we want to always consider those analogies, the Alzheimer’s analogy and the analogy of the empty nesters to know that we can load dual tasking, build redundancies, but if we don’t expose to it, we can also experience some learned non-use, some pruning of those very capacities.

Melanie Hamilton-Basich:
And what do you see as the future of treatment related to dual tasking? What technological advances can we look forward to?

Mike Studer:
So there’s a lot of great information that’s coming out right now about accelerometry, IMU data, wearables to be able to better detect the nuances of how movement changes with and without distractions being loaded. That’s one great way that we really see technology coming into this. Additionally, our ability to utilize technology to be able to introduce and load the different subtypes of distractions is really coming along where we talk about matters such as a Stroop test with a go, no go. And our audience certainly can look up the Stroop test. But to be able to use technology so that the decision making opportunities for the athletes are very timely, very sport-specific, and we can actually measure their reaction speed. And there’s many great producers of technology that is actually also designed to be dual task metricized, if you will, where you can actually measure reaction, speed, and touch a pad, touch a screen.

Mike Studer:
And the computer that you’re tapping can actually determine how quickly you were able to respond to that stimulus in keeping with when it was presented on the board. So that’s really coming along very nicely as well. And the other developments that I see are sophistication of the types of dual task tests, so that we’ve got a greater volume of tests available and that we can actually make them more sport-specific. And the final thing that I see in development is these categories of distractions, and I’ll take a moment to explain here. So first of all, we think about distractions being something that requires the individual to process information. Okay? So process information is, hey, give me the actual driving directions that you would need to go through to get from your house to here at the athletic complex. So that’s process, all right?

Mike Studer:
And I won’t go into further detail, but that’s one category. And another category would be hold and hold means you’re actually putting some things into working memory, hey, I’m going to tell you all your opponents names and numbers that you’re going to meet today. And then I want you to be able to give that back to me later on. I want you to hold that information and I’m going to ask for it back from you. A third of the four categories is recall and recall basically means I want you to grab old information that you’ve stored and you’ve had, and I want you to be able to, while we’re doing this other primary task, give me some evidence of your recall ability. And that could be, when we played West Albany two months ago, who was the player you guarded and what was the score at the end?

Mike Studer:
So that’s recall of information that’s sport-specific. And then the final thing is generate. So we talked about process, hold, recall, and generate. And generate is one of the things that we use currently in dual tasking, but we don’t use it in a sport-specific manner that much. So generate is, well, how many different ways could you use a paper clip? And you try to be innovative and create that list, or name all the states that begin with M, so that’s generate, but we don’t do it in a sport-specific manner enough that engages the athletes. So all right, here’s our sport, our sport is baseball. Name as many different base ball teams as you can, name as many different combinations of counts, name all the different pitches that can be thrown fastball, curve ball, slider, knuckle ball, et cetera.

Mike Studer:
So generate in a sport-specific manner to try to engage the athletes. So I see technology, wearables, pressure sensitive mats, computer-based interfaces and designs. Virtual reality is something I really wanted to say also. And then the concept of hold, process, recall, and generate being the direction that we’re going so that we can have better tests, better metrics, and better engage our athletes. So I hope that gives you a great deal of, I guess, insight into my passion and my expectations for the upcoming world and future of dual tasking Melanie.

Melanie Hamilton-Basich:
Yes. Thank you so much, Mike. Thank you for sharing your expertise and insights about dual tasking. And I want to thank our listeners for tuning in. Look for more episodes in the future on the MEDQOR Podcast Network and visit us online at rehabpub.com and ptproductsonline.com, where you can find many great articles written by Mike Studer.

Mike Studer, PT, DPT, MHS, NCS, CEEAA, CWT, CSST, FAPTA practices in Salem, Oregon. He has been a PT since 1991, board certified in neurologic PT in 1995, and opened Northwest Rehabilitation Associates in 2005. He has been an invited speaker covering 49 states, 9 countries, and 3 continents speaking on topics ranging from cognition and psychology in rehabilitation, aging, stroke, motor learning, motivation in rehabilitation, balance, dizziness, neuropathy and Parkinson Disease. Dr. Studer is an adjunct professor at Oregon State University’s DPT program in Bend, Oregon, where he leads the coursework on motor control and assists the national network of neurologic PT residencies (Neuroconsortium) as well.

In 2011, Mike was recognized as Clinician of the Year in the Neurologic and (in 2014) the Geriatric Academies of the APTA. He received the highest honor available in physical therapy in 2020, being distinguished as a Catherine Worthingham Fellow of the APTA, joining a group of under 300 persons at the time for the history of the profession. Mike’s honors additionally reflect his service, including his vice presidency of the Academy of Neurologic PT and the Mercedes Weiss award for service to the Oregon chapter of APTA. He holds a trademark in dual task rehabilitation and has a patent pending on it.

Over his career, Mike has authored over 35 articles and 6 book chapters, and routinely has clinical research projects in affiliation with one of many universities. As a very fun and lighthearted note, Mike is the four-time and current world record holder for the fastest underwater treadmill marathon, a mark that was set most recently in January 2022 at 3:29:41 seconds.

Read articles by Mike Studer here:

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