Steven Cherry: Hi, this is Steven Cherry for IEEE Spectrum’s “Techwise Conversations.”
In The Tempest, Prospero says, “We are such stuff / As dreams are made on, and our little life / Is rounded with a sleep.”
Lewis Carroll, in Through the Looking Glass, sums up a hundred years of philosophical inquiry known as idealism when he asks, “Life, what is it but a dream?”
Idealism has never really been refuted, but scientists are increasingly looking to manipulating the brain itself to align it better with reality.
Disabilities such as epilepsy, depression, obsessive-compulsive disorder, and even Parkinson’s disease are being treated with neuroimplants. Other scientists are working to substitute hearing for sight in blind people, and still others want to solve blindness entirely by implanting cameras in the brain.
Of course, in all the dramatic advances being made, occasionally a little bit of hype makes its way to our brains as well. A few years ago, a Wisconsin company called Wicab touted a device called the BrainPort, which put an array of electrodes in your mouth so that you could discern the shapes of objects in your environment as sensations on your tongue. In 2007, my then-colleague Sandra Upson wrote it up as a Loser in our annual Winners and Losers roundup of new technologies.
There’s so much going on in man-machine interfaces, I thought we’d bring in a world-class neuroscientist—and computer technologist—who has worked in many of these areas firsthand to sort it all out for us.
Dr. Richard Bucholz has the K. R. Smith Endowed Chair in Neurosurgery at the St. Louis University School of Medicine. In 2004, he won a Missouri Inventor of the Year award for using computer technology to make surgical procedures more effective and accurate. And he is also a leading participant in the Human Connectome Project, a $30 million National Institutes of Health initiative to map the human brain. He joins us today from St. Louis. Richard, welcome to the podcast.
Richard Bucholz: Thank you very much.
Steven Cherry: Richard, there’s something called vagus nerve stimulation, if I’m pronouncing that right, that’s used to treat both depression and epilepsy, which I think most people think of as two very different things. What is it, and how does it work?
Richard Bucholz: Vagal nerve stimulation has to do with a device implanted around a nerve that travels along with the carotid artery in the neck. The vagus nerve is involved with controlling the gastrointestinal system and is also involved in transferring data from the gastrointestinal system to the brain. So there’s both a motor and sensory nerve. It has been found that manipulation of this nerve can have a variety of effects on the brain. One of [them] obviously, of course, involved with epilepsy. It turns out that stimulation of this nerve can actually desynchronize the EEG, where synchrony in the EEG is the sign of epilepsy, or of active seizure.
Therefore, vagal nerve stimulation for epilepsy is now a very typical neurosurgery that we do in epilepsy, involving an electromagnetic mechanical device, a small procedure, and placing these leads around this rather small nerve, in terms of controlling epilepsy. The technology for even that application is increasing. There’s now interest to be able to detect a seizure reporting from the vagal nerve, so the device, instead of firing on a routine basis and causing side effects of hoarseness, can actually fire when a seizure is coming on. And there’s now software that may be able to predict the presence of a seizure as much as 50 minutes ahead of time, so that you can actually just stimulate the nerve when you need to, to prevent a seizure. It’s also been shown that stimulating the nerve gives feelings of happiness. Perhaps this is responsible for the feeling we may all experience after a large Thanksgiving dinner, and we are full, and we’ve had a great meal—that’s probably in part orchestrated by the vagus nerve.
So there was interest in stimulating the nerve for people with intractable depression. And indeed we have now found that stimulation does indeed help in a population of people with intractable depression. Those people who have undergone electroshock therapy, five rounds of different antidepressant medications, other interventions, and still have extremely severe depression, such that they are completely disabled by their psychiatric disease. In this population, we have been able to demonstrate up to 70 percent of patients may respond when they exhibit specific patterns on preoperative imaging.
Steven Cherry: You’ve also worked on technologies that involve blindness and deafness. Let’s start with blindness.
Richard Bucholz: There was a project here at St. Louis University that was continued in Europe, having to do with visual stimulation of the cortex by a camera system mounted on a highly modified pair of glasses. The idea here is that these cameras would take in a visual scene, transmit that to a series of discharges, be processed by a computer on the patient’s belt, and then transmitted to electrodes directly overlying the visual cortex of the brain, called the calcarine cortex. The...this was done on a series of approximately five to six patients. The interesting thing about this was that these patients did seem to become orientated to their visual surroundings; they seemed to be able to interact with their surroundings better than when tested against people who were totally blind. However, the maintenance of this device was highly problematic. Whenever you’re talking about a complex technology such as this computer that would analyze these, there was always the idea of revision...a-ha. That is, the LCD cameras would improve, the computational capabilities of the computer would improve. However, the thing that would not improve was the implant lying on the brain, because you clearly can’t take the patient back for each revision of the electrodes. So there was a common thread going through that entire research that the electrical technology was improving, but the interface between the technology and the brain was not evolving, and this finally led to a termination of the program. And now we are faced with the task of removing these devices while not disturbing the underlying cerebral cortex. So there are all sorts of philosophical issues whenever dealing with a technology and any type of interface situation to the brain.
Steven Cherry: Yeah, I just—it does sound like really interesting research, though. I’m curious, what is the patient actually experiencing? How do they describe it?
Richard Bucholz: Oh, they describe it as flashes. These are people who will say, yes, I’m getting flashes. And then you put it through a training process so that the flashes can then be correlated with specific items. The camera, for example, when approached by an ambulance, would have a great deal of discharges, so there would be a whole bevy of flashes that would occur to the patient. And then you would have the patient associate that with the approaching of an ambulance. The interesting thing is too that you could also correlate it in those people who are congenitally blind with movement of the head, so that they could understand that by moving the head you change your scene. This is something that comes naturally to a person who’s been sighted their entire life but is not necessarily natural to somebody who’s congenitally blind. They do not necessarily know to change and move their eyes around if they’ve never used their eyes, in order to change the scene and to improve the awareness of their surroundings.
Steven Cherry: Now the work on deafness is in a way similar to blindness, except that instead of a camera, it’s a microphone. How does that work?
Richard Bucholz: This is a procedure done fairly routinely in many medical centers now and varies somewhat, based upon the site of the deafness. In general, a microphone is placed behind the ears, in a place called the mastoid. A wire is led into either the cochlea, which is the hearing organ centered in the skull base, assuming that the cochlea is functional, or in situations in which the cochlea has been damaged, it is placed against the brain stem, where the auditory nerve enters into the central nervous system. In the cochlear implant, the situation is that you can actually take sounds and transmit them and turn them into a spatial representation of the frequency. That is, in the cochlea, high notes are heard in a specific area in the cochlea, whereas low notes are heard in another area. You can actually make up for the mechanical characteristics of the cochlea using this implant, so that now you can take sound and turn it into high- and low-frequency components, depending on which part of the cochlea is being stimulated by the system.
So in a way, you can actually restore very useful hearing, such that these individuals can make out speech, etc., in a socially useful fashion. With brain stem implants, it’s a little more difficult. There, the so-called organization, in terms of tonotopic organization of tones versus locations, is not as well organized as it is in the cochlea. And there it’s more of an appreciation of a presence or absence of noise and maybe some of the spatial information. But again, the chances of restoring vocal recognition in a patient without functioning cochlea is much less well achieved.
Steven Cherry: The BrainPort that I mentioned at the top of the show is an example of sensory substitution—in that case, the tongue. And that’s got obvious problems, but some people are very enthusiastic generally about the strategy of sensory substitution. What are the pros and cons here?
Richard Bucholz: Well, the real problem is people who are candidates for sensory substitution by the very definition means that one of the sensory modalities is absent. So, obviously, in the situation of blindness, you have no visual input, and so these are individuals who have highly developed senses of hearing. Now the problem is, is that if you take visual information and superimpose it upon auditory information, you may actually overwhelm this system that has become highly adapted and sensitized to auditory input and confound it with this visual information. And so the result may be a more confused and less oriented individual, simply because you have taken the remaining senses and tried to multitask these remaining senses and literally overload them with information, because they just can’t handle all that through the remaining senses. So that has, you know—again, it’s attractive in that you already have those sensors in place, you already have an attached ear, a tympanic membrane, a cochlea, so wouldn’t it be nice to take that person and make them see through sound. But at the same time, maybe you’re taking away their ability to see through sound in terms of their already highly developed sound capabilities.
And you may actually make them less well off. That’s where in my area of interest, I have become more focused upon not using the existing sensors but using that part of the brain that would have been dedicated to that missing visual function and going directly to that, through some sort of implant that, you know, bypasses the diseased part that is no longer functioning.
Steven Cherry: That takes us straight, I think, to the Human Connectome Project, which I wanted to ask about anyway.
Richard Bucholz: Well, the Human Connectome Project is one of the fascinating areas, and that is, as a neurosurgeon, I have been asked to intervene and navigate through an organ which is obviously the most complex structure that we know of in the universe and at the same time is basically unknown to us from the standpoint of a wiring diagram. It’s somewhat like if someone asks you to fix your smartphone and not have any type of schematic or even know where the battery was located or the screen was located or any of the other functional parts of the smartphone. It would be very nice, as a neurosurgeon, to have a basic wiring diagram of where the parts are to the brain. Where is the visual cortex, the auditory cortex, the motor cortex, etc. Now, to a certain degree, based upon studies of people with strokes and trauma, we kind of know where the visual cortex is and the auditory cortex, in a very highly stylized fashion.
But the point is, is that those people who have been studied, with damage to normal brains, do not necessarily represent those that we operate on a routine basis. For example, whereas the visual cortex in the person who’s blind, well, many of these people there’s such plasticity that their brains become completely reorganized, and in that case taking our knowledge of normal patients and trying to apply that to these abnormal brains—abnormal in that they have been modified to suit some sort of deficit—is highly problematic. And you may find yourself intervening in an area that you thought was safe but is actually critical to the function of that individual.
Steven Cherry: You know, we talked about cochlear implants before, and I did want to ask you, there’s a segment of the deaf community that doesn’t see deafness as a handicap so much as just a difference, like having red hair or short arms, and they see things like cochlear implants as potentially a civil rights question. I’m wondering if you see any moral issues here in all of this brain work.
Richard Bucholz: Well, it is a fascinating area, in that the technology is literally rife with moral issues as well. One of the traditional things that we as neurosurgeons see all the time is people who come in with their statements saying, “I would not want to live if I were paralyzed from the waist down.” Well, the fact of the matter is, none of us know what it’s like to be paralyzed from the waist down. It so turns out that we, as neurosurgeons, have a whole bevy of patients who are indeed paralyzed from the waist down and who are living rather happy, fulfilled lives. And if you said to these people who experienced paralysis, would you not want, you know—if you came into the ER, would you want us not to do anything because you’re paralyzed from the waist down, just like these people have said in their, you know, their living wills, they would say, “Absolutely not, I enjoy my life, this is a functional, meaningful life.”
This is just like people who are deaf, people who are blind. People, these people, are not necessarily disabled from their point of view. They’re living extremely fulfilling and useful lives. Whether you restore or give them a function or not is something that they need to make a decision on themselves. At the same time, because many instances they’ve never experienced vision, they’ve never experienced hearing if they’re deaf, they don’t—aren’t in the best possible situation to comment on whether or not they’d like to experience vision or not, because they don’t know what it’s like. So you’re dealing with very difficult moral questions of restoring function to an individual who may not really want function restored but at the same time doesn’t really understand the quality and importance of the function to living even a more fulfilled life. So it’s a very difficult area, and one that we get into all the time.
Finally, there’s another huge moral issue coming around the horizon, and that is, let’s say we can restore function in the supernatural fashion. Let’s say by placing an implant we could increase your IQ by 20 points. Well, do we as surgeons and clinicians take on potentially risky procedures to give people 20 IQ points, knowing full well that that’s probably something only the wealthy are going to be able to afford and knowing that many people who do not have financial resources are not going to be able to have their IQ improved by 20 points. These are very sticky moral issues that there is no easy solution to.
Steven Cherry: I was going to ask you about that very thing, that, you know, in the same way that one person can be, say, color-blind and not realize exactly what it is to see an entire spectrum of color, you know, so too, I’m probably color-blind when it comes to taste. You know, I hear these people sipping their wines and talking about these qualities that I can’t taste in them. Maybe you could restore me from the taste version of color-blindness to full taste capacity.
Richard Bucholz: But—and I would ask you—how would I be able to, as a neurosurgeon, get informed consent? Because, you know, there I have to tell you the risk and benefits of the proposed procedure. Well, the benefits are restoring tastes that you never had. So how would you be able to understand that benefit, in order to weigh it against the demonstrable risk of intervening in your brain? That is a very difficult question to do. People talk about informed consent, and you just have to laugh at times, because there are times in neurosurgery where you can’t really, you know, instruct the person as to what the benefit of the operation is, because they haven’t experienced it.
Steven Cherry: Eventually the risks will be reduced. I mean, nowadays surgeons do quadruple-bypass surgery that used to be incredibly risky, and not so much now. When the risks are reduced, do you think that we’ll start to see certain man-machine hybrids, you know, routinely?
Richard Bucholz: Oh, that’s already there. We currently do a procedure for Parkinson’s disease in which we introduce electrodes deep into the deepest parts of the brain on a routine basis. I remember showing a postoperative scan to one of my neurosurgical colleagues. He said, “Oh my god, you have electrodes in the brain stem!” And the fact of the matter is, we do this twice a week, three, four times a week on a routine basis, on very elderly patients, with very low risk. And we do this because it gives them remarkable benefits in terms of restoration to an earlier time that they know about, because this was function that they lost in the course of their Parkinson’s disease. So…
Steven Cherry: I guess what I’m wondering is if we’ll see—if we’ll start to see—the, I guess, cosmetic surgery equivalent for brain work. You know, just improving people’s sense of sight, or to even a greater degree, their ability to recognize things better, or improve taste, as I mentioned before.
Richard Bucholz: Yep, the risk has been decreased so much at this point that although not cosmetic surgery, literally I had the conversation today whether we should be doing this on a day-surgery basis, having people come in, having electrodes inserted in their brain, and having them discharged from the hospital in 24 hours. Literally, almost all of our patients are going home within a day now of their electrodes being placed in their brain. This would have been unthinkable, you know, three to four years ago.
Steven Cherry: On a more personal note, you’re something of a hacker, I guess, just by nature. I understand, for example, you don’t have any light switches in your house.
Richard Bucholz: [laughs] No, I don’t have any, I only have touch screens in the house, at my house, yes.
Steven Cherry: That’s pretty wild. So, have you always been a hacker?
Richard Bucholz: Very much so. I can remember at the age of 10 I was fascinated by electronics. I actually got into neurosurgery from taking courses in computers and things. And I had to take a divisional requirement in biology, and the closest thing I could see to computers was neurophysiology, and all of a sudden I found out that along with an interest in computers I had a fair amount of dexterity, so that’s how I got involved in neurosurgery.
Steven Cherry: That’s terrific. Richard, it’s just amazing the things that are being worked on now, and you’re right at the center of it, so I want to thank you, and thank you for joining us today.
Richard Bucholz: Well, thank you so much for this opportunity. Loved talking to you.
Steven Cherry: We’ve been speaking with neurosurgeon and hacker Dr. Richard Bucholz about neuroimplantation and the brave new world of man-machine interfaces.
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