Walter Greenleaf: Virtual Reality and AI in Healthcare

Guy Kawasaki:
I'm Guy Kawasaki, and this is Remarkable People. We're in a mission to make you remarkable. And today we have with us the remarkable Walter Greenleaf. Walter is a neuroscientist and medical technology developer. He works at Stanford University. He's the leading authority in digital medicine and medical virtual reality. He has designed and developed clinical systems including products for surgical simulation, 3D medical visualization, clinical informatics, and simulation-assisted rehabilitation techniques.
He's the co-founder and board chair for the International Virtual Reality Health Association. He has served as the principal investigator for research projects funded by the National Institutes of Health and NASA. I'm Guy Kawasaki. This is Remarkable People. And now here is the remarkable Walter Greenleaf. Do you know about the Ray-Ban Meta partnership where they have sunglasses with a camera and AI built in?
Walter Greenleaf:
Yes, I do, and I've run across a few friends who are wearing them. It reminds me of the Google Glass, of course.
Guy Kawasaki:
Is it reality? Because with that, you could just say, "What am I looking at? What's the history of this city? What's the history of this building? What am I seeing?" So it's a combination of this visual representation plus AI. So is that reality now?
Walter Greenleaf:
It's getting there. And I think the other layer that's on top of that is not only will we have visual representations of extra information overlaid upon what we're seeing, and this is an interesting issue, there's a lot of work going on with capturing eye gaze, facial expressions, body language, voice tone to come up with scores related to our mood, our emotional state, and how alert we are, how grumpy we are.
And that'll be overlaid too and filtered. So I could be filtering my interactions with you right now, both visually and auditorily. I could say I want to look a little more friendly, or I want to look a little bit more savvy, and that's what you would be seeing. So as we interact with the built environment and with each other, there's going to be a layer of technology between and us and each other, and that's going to be an interesting change.
Guy Kawasaki:
I saw that you reshared an article about tracking eye movements to use in diagnosis. So you're telling me that someday in the future we could have this kind of virtual conference and at the end you say, "Guy, by the way, I think you have Parkinson's?"
Walter Greenleaf:
I think we're there. I think there's ways to do that right now. The quote by William Gibson, of course, "The future is already here - it's just unevenly distributed." And I think using eye gaze and voice tone as a way of diagnosing neurodegenerative disease like Parkinson's, we can do that, but mostly the research zone hasn't been translated out.
Guy Kawasaki:
And I'm sure people are listening to this and their heads are exploding and they're saying, "Maybe Mark Zuckerberg knows my moods because he's watching my eye movements and he knows if I have Parkinson's. And that's a little scary."
Walter Greenleaf:
Oh, I think it's both exciting and scary. It's exciting because, hey, with an aging population, as the boomers get up into their eighties and nineties and longer, because we're all going to live a lot longer, there's some challenges that we will have. We want to keep our brains healthy. We want to keep our bodies healthy. We want to age in place. We want to expand our health span.
Instead of having a long, slow decline, we want to be fantastic until we're not. But the technologies we have right now will help us with that. But again, there haven't been positions to scale. It's exciting to have these new breakthroughs that will help us with not just better diagnosis, understanding if you have Parkinson's, but new therapeutics and ways to do it more precisely for you because we're all different.
There should be different prescriptions and interventions. The scary part is exactly what we were looking at earlier, that this is very personal, very private information. It's right now available publicly. When you're on an online game and playing with other players and speaking, your impulsiveness could be scored, your abilities as a leader or a follower. Your voice tone can indicate your mood.
There's a lot that can already be extracted publicly, and even more so privately that we just have to find ways to lock down and protect. And so yeah, people should be worried about as the tech titans move into this zone. And especially as they move into healthcare, it's exciting. We need it. We need better technology. We have an aging population. This is going to be extremely expensive to address worldwide, how to support people living so much longer. It could be more expensive than dealing with climate change, but there's also very sensitive issues we have to address.
Guy Kawasaki:
I think we should just hook this up to JD Vance right now and get insights into his head, but that's a different subject. You opened the door here for me. So can you just describe the state-of-the-art of the neurology of getting old, brain health as you get old? What's the latest, greatest insights into that?
Walter Greenleaf:
I think the first thing we should remind everyone is that what's good for the body is what's good for the brain. So if people say, "What can I do now to help my brain be healthier when I'm in my seventies, eighties, or nineties," it's sleep, exercise, diet, stress, reduce stress. All the things that keep our body healthy we know keep our brain healthy. So that's one thing you can do to mitigate the risk.
That said, those things may or may not make a big difference if genetically you're on the pathway to develop Alzheimer's or Parkinson's or some of the other neurodegenerative diseases. Invest in research would be one thing I would say is that there's some great potential therapeutics both as molecules and pharmaceutical interventions, but other technologies that can help us intervene and we need to move forward with them as best we can.
Because again, three out of every seven of us when we get up into the age zone, that's the way things are, develop Alzheimer's or Parkinson's or Lewy body disease or some other things that we don't want to have happened. So yeah, keep your brain healthy now by doing what keeps your body healthy, but we need to move forward. With an aging population, we've gotten maybe ten years before the tidal wave hits, but we do need to move forward.
Guy Kawasaki:
So is the corollary also true that good for the body, good for the brain? Does that mean bad for the body, bad for the brain?
Walter Greenleaf:
Yes. I'm guilty of not getting as much sleep as I should or exercising as much as I should. And I'm very conscious that this is a trade-off versus keeping my brain healthy. Yeah, that's our current thinking.
Guy Kawasaki:
Okay, good for the body, good for the brain. But are there things that are good for the brain? Is it like playing Sudoku, or is it playing chess? Are those things just a fad from these influencers and thought leaders want to sell stuff? Or do these kind of mental things really help?
Walter Greenleaf:
We're getting into a zone where there's controversy, and I'll tell you what my opinion and my beliefs are. And I'm sure I'm going to get some pushback from my esteemed colleagues who disagree, but here it goes. It used to be viewed that many of the things that were being brought out there by some of the companies that had games for brain health, for example, the claims were exaggerated.
That groups would say, "This will prevent the possibility of having Alzheimer's, or this will address or cure attention deficit disorder." And a lot of the research did not really back the claims that were being made. That was the past.
Now we know that there are some things that we can do that are impactful and make a big difference and can help. There's recently been products and, for example, games you can play, that you can get a prescription from for a doctor, you can get a prescription for something that helps with attention deficit disorder.
We know that there's some interventions that can be used that will help you with what we call executive functions, some of the decision-making and navigation skills, et cetera. Very interesting work by Adam Gazzaley's group at UCSF looking at how we can play a game. They have one called NeuroRacer that Noah Falstein helped design that improves the scores that people in their sixties have that normally are very low compared to people in their twenties and certain executive functions.
But if you play this game, not only can you raise your scores up to what you would've had in your twenties, they've gone back years later to see if it persists, and it does. Now, the evidence, in my opinion, is that yes, there are things that we can do in terms of exercising our brain that make a difference in terms of cognitive decline.
Guy Kawasaki:
I am really interested in this topic in two regards. First of all, I'm seventy, so I would like to know exactly what to do, not just conceptually, but just tell me. If you and I were best friends and I asked you, "Come on, Walter, just tell me what do I do? Will you just tell me the game, or what do I eat? Or what should I do, Walter?"
Walter Greenleaf:
Guy, come back to me in a week and I'll have a more refined answer to that because there's a lot of different options. And also I would want to know a little bit more about you. I think one of the challenges we have in healthcare is that we have a one-size-fits-all. This is what everyone should do. And I would need to know a little bit more about you, and I would also want to know your goals.
Is your goal to live as long as possible? Or is your goal to have the highest quality in the next thirty or forty years? Is your goal to continue to work, or is your goal to continue to enjoy leisure? So there's more I would need to know before I could give you a good answer, but I'll think about it. And maybe if we talk further, I can understand what I could recommend. But I'm not a clinician.
I'm an activating enzyme, helping the clinicians and the healthcare providers and the scientists and the healthcare networks understand what's new and what they should look at, but I'm not the person who writes the prescription.
Guy Kawasaki:
I actually have great respect for that answer because it shows it's not a flippant answer that you're just talking shit basically. A slightly related thing. Now, you mentioned that there are games that can help kids with executive function. What's the game for that? I want to hear that.
Walter Greenleaf:
All right, there's two products that were developed by a company named Akili. There's a company that I have great respect for, Akili, that developed two games. One that is available over the counter, meaning you can download it from an App Store, and that's Endeavor, E-N-D-E-V-O-U-R, and then there's EndeavorRx.
Endeavor is for adults with ADHD, and EndeavorRx is positioned for children who have ADHD. EndeavorRx requires a prescription to get, but the other form of Endeavor for adults can be downloaded from an App Store. And these are validated intervention.
Guy Kawasaki:
Wait, I'm trying to wrap my head around this. If a parent is listening to this and they're part of Kaiser, they call up Kaiser, they call up the Palo Alto Medical Foundation, and they speak to their pediatrician. They say, "Give me a prescription for EndeavorRx."
Walter Greenleaf:
I'm actually not sure if you need to go see a specialist. But yes, that's the basic concept is that these are validated interventions, prescribed video game for treatment for children with ADHD. And I just went to their website, www.E-N-D-E-A-V-O-R-R-X.com There's a tab for getting a prescription for people to follow up.
Guy Kawasaki:
Wow! Oh my God! So are you saying that this thing went through FDA trials?
Walter Greenleaf:
Guy, you are partially responsible for this. What you did back in the eighties and nineties to help move forward digital technology, it's helped put us in a position to be able to have things like this. Thank you for that.
Guy Kawasaki:
Okay, here's to reaping what you sow. So now getting out of this particular topic here, I want to move back up to virtual reality in medicine. So what is the current cutting edge of virtual reality in medicine?
Walter Greenleaf:
We're using VR right now for better training of clinicians of surgical skills or understanding neuroanatomy in three dimensions. We're using it for better assessments, a better way of doing a differential diagnosis for anxiety, depression, attention deficit disorder, different aspects of stroke or traumatic brain injury.
And we're using it for better therapeutics, ways to promote better recovery from an injury or ways to address addictions or ways to help people who are on the autism spectrum learn how to recognize body language and facial expressions and others. So really the full stack of healthcare has been impacted by the technology. The Veterans Health Administration has done an amazing job of rolling it out, and they're our largest healthcare network.
They've trained more than 3,000 clinicians. I think they're using it for more than thirty different clinical indications throughout their network. And again, still at an early stage in many ways. It's been held back because new technology in medicine very appropriately takes a while to get established, especially because of our business model of needing to establish a code for reimbursement.
And that's why the VA has been able to move forward faster than other groups because they don't rely on reimbursement codes. They'll roll something out and use it if it's impactful. So it's happening. I'd say though we're at that transition point from early adopters and the people that are willing to try new things for better results. It's now starting to move over into just how we do things and get beyond that early adopter threshold, especially for pain.
There's some fantastic ways to both address acute pain and chronic pain using virtual reality and augmented reality technology that's been well validated and it's starting to be used throughout the healthcare system.
Guy Kawasaki:
Wait, so how can doing something online with virtual reality relieve pain? Isn't pain at a chemical level?
Walter Greenleaf:
It doesn't have to be done online. It could be, but two ways. For an acute aspect of pain, it can distract you if you're getting a lumbar puncture, for example, or they're degrading your skin, which is very painful, for a burn injury, or if you have back pain. For chronic pain, we teach skills. We use virtual reality as a medium to people to learn mindfulness, relaxation skills, to learn how to mitigate their pain, to reframe the way our brain reacts to a pain signal. And it works. It's been validated.
Guy Kawasaki:
And where does AI come into this? Is it people in India who have MDs, or is it AI scanning X-rays and looking at results and giving you recommendations?
Walter Greenleaf:
AI is really empowering everything. All these new digital health applications we've been talking about, not just the VR and AR, require very sophisticated analytics. And we now can extract more from the signals that we have to do more. And then also because of generative AI, we can take the analytics and we can use it in the case of virtual reality or augmented reality, for example, dynamically change the user's experience based on those signals.
So AI is empowering us both to do better diagnostics, to identify a lesion that might be seen on an X-ray that might not be able to be captured easily by the clinician to support the clinicians to do that, or to help us look through some data and find the key features, both on a research level and on an individual level that we need to have.
So remember I mentioned earlier that in order to answer your question about what helps you, I would need to know you a little bit better. AI is helping us look at the data from an individual, understand them a little bit better compared to the larger population, and make recommendations as to what would be a precision way to help you with your healthcare problems.
Guy Kawasaki:
And these treatments, they're being tested scientifically, double-blind placebo effect, all of that kind of stuff. It's not just Donald Trump saying drink Clorox. This is FDA, everything, the whole shooting match.
Walter Greenleaf:
We've had more than thirty years’ worth of research on specifically for VR technology for healthcare, decades of research. And that's just in that zone. The other zones we're talking about even longer, but the technology hasn't been affordable until recently. So we're now in the process. That's why it's the process of moving it out of the research labs into clinical care, doing the validation studies.
But yes, we've done double-blind placebo-controlled studies of the impact of these digital health interventions and the FDA reviews them. I was part of a team at a company named Para Therapeutics, which was the first company to establish software as a medical device, so that the FDA will review and regulate these interventions and make sure they're healthy and safe and effective just like they do any other pharmaceutical pill or any sort of other device.
And here's the cool thing, Guy, is we're also now starting to see combination therapy, where it might not just be a pill to manage depression or anxiety or pain, but a pill that is used in combination with the digital health app that can help you, again, adjust it for you individually, see what's working, what's not working by measuring the impact of the therapy, and then maybe doing something in combination.
And for anxiety, maybe not just taking a medication, but also learning relaxation skills, mindfulness skills, et cetera. So it's not just either/or. It can be together, combination. And that means we can leverage the established distribution channels that the pharmaceutical companies and the medical device companies have to bring out these very powerful digital health applications.
Guy Kawasaki:
Can you just give us an idea of a specific treatment? I read that, and I think you mentioned, that there's software as a medical device to help people with PTSD. So let's say you are undergoing this treatment. Exactly what happens?
Walter Greenleaf:
For post-traumatic stress and also for addictions and anxiety disorders in general, we use an approach called exposure therapy, where what's happened with post-traumatic stress, and I'm being very simplistic here for the sake of not spending twenty hours going over it with you, what happens with a learned fear reaction like post-traumatic stress where you've had some trauma, and your brain has very appropriately learned to fear what almost killed you or what was uncomfortable for you.
But that's useful when we were evolving. But now in today's world, some things that can be traumatic, it might be something that happened to you in combat or something that happened to you one time, but you're having an overreaction, you're being triggered and you're having challenges, so we use exposure therapy to address that.
Same thing with addictions. You may get beyond the metabolic aspect of an addiction, but you still are triggered by cravings when you go into a bar and your friends are drinking a beer, or you go by some place where dealer used to sell you meth.
So in both situations, what we use is to gradually teach people to understand what is triggering their reaction and to gradually habituate that reaction, to take what's a learned fear reaction or perhaps a learned craving and turn it into something that your forebrain is reacting to and saying, "Oh, there's a pile of trash on the side of the road. But I'm driving on Interstate 280 in California. I'm not over in Iraq. That pile of trash is not necessarily a threat. So I don't need to get really upset when I see a pile of trash on the side of the road."
And we use virtual reality, for example, to gradually expose you to what is triggering those reactions under the supervision of a clinician and teach you how to manage your learned fear reaction and to habituate the response. And it works. We get great results.
Guy Kawasaki:
When you say you're using virtual reality, are the people wearing headsets? Is it like a Apple Vision Pro? Is it that level? They really think they are in this.
Walter Greenleaf:
For exposure therapy, you don't have to wear a head mounted display. For a long time, people have taken people with fear of flying to an airport and having them go up. But if you're doing it in vivo, in real time, it's expensive. So the advantage of using a VR system is we can do it in a clinic. And in some cases, we can do it online like teaching people who have a fear of public speaking, for example. We can rehearse online with a virtual audience and practice.
But for a learned fear reaction, post-traumatic stress from an IED explosion in Iraq, we really do want to use a VR system because then we can block out the outside world. The brain doesn't want to go there if it's something you're traumatized by and you're scared of. And I start talking to you about it and say, "Guy, remember that horrible thing that happened to you," you're going to be triggered.
But I can gradually take you there if I have a way of blocking out the rest of the world and say, "Let's start by walking up to the ticket counter at the airport." So it's not just post-traumatic stress, it's also phobias that we can treat using exposure therapy. And then I gradually evoke the learned fear response without retraumatizing you because I have control of how the level of reality, the level of exposure you have and teach you the skills and habituate your learned fear response.
Guy Kawasaki:
Wow! Walter, I got to say it, if anybody else was telling me this, I would be saying, “This guy is full of shit."
Walter Greenleaf:
I'm telling you about what other people have done research on. There's been decades of people working behind the scenes developing this new wave of technology, and it's finally coming out, which is great because we need it.
Guy Kawasaki:
My head is exploding here. Until I prepared for this interview, I never heard of this concept as software as a medical device. So what's the career path? Let's say somebody is listening to this and saying, "Man, this is the coolest stuff. I want to do this. I don't necessarily want to be a general practitioner or a pathologist, but I just love this application of software." So what's this person's career path today? Do you go to medical school? What's the whole thing you do?
Walter Greenleaf:
I think if you'd asked me this five years ago, I would've said find an academic research center that is studying how to use digital health and virtual reality technology and other technologies for pediatric care, for example. I'd say find a group that has an indication that you're interested in. Maybe you're interested in helping children who have had stress from the pandemic learn to manage to help with their mental health issues and work at that academic center.
That would've been a while ago. Now I think I could say that's one option, and that would be great, we could use your help on the academic research side, but now we're starting to see the technology move. And there are companies, public companies, Penumbra, for example, is one. They're selling virtual reality products to treat traumatic brain injury, to treat post-traumatic stress, to treat mental health issues, to help with neuro rehabilitation. That's one of their fortes.
It would be more go to a center, continue with your career as a clinician, but make sure you're aware of what's possible and get your hospital, get your clinic to up their game by bringing these new technologies in. So that would be one way. Another way is to get involved not necessarily as the clinical or research side, but also on the tech side. We need to put additional layers of technology on top of what we're doing so that we can do more.
We can leverage machine learning to look at the data a little bit better and come up with, again, a precision approach to fine-tuning the intervention to match what the individual needs.
Guy Kawasaki:
So do you think this is going to take longer, or in five years, we're going to just be amazed at what has happened? Because Bill Gates has this theory that things happen faster than you think they are, but not as fast as these visionaries say.
Walter Greenleaf:
I guess it depends. I think we have the technologies that can make a big difference. The tech titans are moving into healthcare. Apple, Google, Samsung, Amazon, Meta are all starting with consumer health and wellness, which is fantastic, but some are moving into the clinical zone too.
I think as that happens, the speed will pick up because the tech titans know how to design for scale and they know how to design good user interfaces, which frankly, the medical device and the pharma companies have not had that skill set before, and their business model has been more slow and careful, which is appropriate for medicine.
But I think now that there's new players coming into the game. Also the other things that gives me a reason to say things will happen faster than otherwise, so we have some acute needs.
We're dealing with three major problems right now. One is in aging population, which will cripple our economy worldwide if we don't do something about it. If three out of every seven of us has Alzheimer's in our seventies, eighties, or nineties, there's smaller families and there's a wave front of people getting older, especially in Asia, that's going to be extremely expensive unless we get on top of it.
At the other end, we have a whole strata of youngsters who went through the pandemic with seeing their parents completely fearful, not able to go to kindergarten and learn social emotional learning skills, learning a lot of fear and stress. And so if you talk to our colleagues in pediatric care at the children's hospitals, they're saying an avalanche of new problems in mental health.
And also our society in general, I think, is challenging our mental health issues for so many reasons. And then meanwhile, the overburdened healthcare system with so many burnt out clinicians who have been really working so hard. So those three issues can't be solved by anything other than technology right now. We can't grow family members fast enough to support the aging population better. So it has to be technology and the tech titans are moving in.
So I have reasons to be optimistic that things will happen faster than not. I've been wrong so many times before. I always think five years from now, we'll start using this technology. But it is happening. I look at what the VA Health system, for example, is doing and I feel like it's starting to happen. But hey, your listeners can help it happen too. Let's ask for these technologies. Let's invest in these technologies. Let's make it happen.
Guy Kawasaki:
I have to say, when I watched your video of you talking to the VA Health system, I think like many other people, I have this impression in my brain that the VA Health system is broken, and you read these articles about people waiting eighteen months to get an appointment. This is like government bureaucracy. It's just the worst thing. And then I watch your video and you're telling me they're the early adopter and they're the pioneer. I love that.
Walter Greenleaf:
Sure, governments have a tendency to be aggravatingly slow and frustrating. But within the VA, there are some amazing people and they have really pivoted to innovation, to encouraging innovation. At that conference where you saw the video from, Guy, one of the opening remarks by Anne Bailey was a quote from Margaret Mead that never doubt the power of a small group of individuals to change the world is the only method that has.
And I think there are some great individuals within the VA that are changing things. So yes, there's been a legacy of slowness and government bureaucracy. Congress is their board of directors, and sometimes managing your board of directors is a problem in general. But if it's Congress, even more. Please don't get mad at me, Congress, but they're making it happen.
I also think the boomers grew up loving gadgets and technology. And I think that as we age, we're going to be asking for the latest and greatest and purchasing it on our own if it's affordable if we can't get from our docs. I think there is a pathway to be optimistic about this.
Guy Kawasaki:
My last question for you, Walter, and I need you to put all semblance of modesty aside. And my podcast is called Remarkable People, and we're on a mission to help people become remarkable and make a difference. And obviously we consider you remarkable because we have you on this episode. So again, putting modesty aside, if you can look back on your life and say, what has enabled me to do such remarkable work?
Walter Greenleaf:
I would say that what has enabled me to do such remarkable work has been I had a very wonderful childhood of, and that's helped me feel self-confident. I've also enjoyed meeting other remarkable people along the way. And so the confluence of where I went to college, which was an experimental college called Hampshire College, it was just getting started at the time, no grades, no required courses, and I met some amazing people as colleagues then.
And then just as I've been fortunate enough to run across some incredible people as friends, Jaron Lanier was my best friend during grad school at Stanford, Eric Horvitz, who set up Microsoft Research Labs also. So I've been fortunate by running across amazing people that helped me go down my pathway. Like all of us, I think it's a combination of seeing some doors open and going through it, but we need the good fortune of those doors to be around.
If we're able to grab the hook as it goes by, then we're fortunate. But if the timing doesn't work out or we don't have that fortune, it doesn't mean we're not remarkable. It just means that we didn't have that opportunity in front of us.
Guy Kawasaki:
All right, I just thought of one last question, which is, Walter, what do you want to be remembered for?
Walter Greenleaf:
Oh, I honestly will put aside all modesty here again, because you asked, Guy. I honestly don't really think about being remembered. I want to have an impact in my lifetime. That makes me happy, but I don't feel it has to do about me at all. To the extent that I can see things that I think are helpful and important happen, especially involving what can happen with science and research and tech coming together, then I'm happy. It doesn't have to be me.
But what I hope is remembered is that this was a time where our generation took the challenges in front of us and found pathways to solve them. And there's many things to worry about, of course, climate change conflict, but also those three big healthcare challenges I mentioned. I think we can solve them and I hope we do and I think we can. I will remember this time with a smile if we rise to the occasion and address some of these challenges instead of just missing that opportunity.
Guy Kawasaki:
I hope that you've enjoyed this little window into the future, although, as Walter has pointed out, maybe it's not "the future," maybe it's here already and we just have to more evenly distribute it. I'm Guy Kawasaki. This is Remarkable People. I want to thank the rest of the Remarkable People team. That, of course, includes Tessa Nuismer, our ace researcher, Madisun Nuismer, she is the producer of this podcast, co-author of Think Remarkable with me.
And finally, she's the co-author of the Substack newsletter that we have. I don't think I've ever mentioned the Substack newsletter on this podcast. What a bozo! Check out our Substack newsletter where every week we put out an issue about how to be remarkable. Where was I? Oh, the rest of the Remarkable People team. That would be the sound designers extraordinaire, Jeff Sieh and Shannon Hernandez. And finally, there's Luis Magaña, Fallon Yates, and Alexis Nishimura.
Finally, I want to thank Jeanne Seeley. Jeanne Seeley and I worked together in the Macintosh division a long time ago. And poor Jeanne, she was kind of tasked with keeping me in line. That was a very big challenge. I hope you hear this, Jeanne. Thank you for introducing me to Walter. Alrighty, that's it. I'm Guy Kawasaki. This is the Remarkable People team. We're on the mission to make you remarkable. And until next time, mahalo and aloha.