Posted in big data, bioengineering, complex systems, driverless cars, drones, electronics, engineering, information science, neuroscience, robotics/AI | Leave a Comment on Bio-Mimetic Real-Time Cortex Project — Whole Brain Emulation — Dr. Alice Parker — University of Southern California — ideaXme — Ira Pastor
Last year, OpenBCI burst onto the scene with a Kickstarter campaign to fund development of an open source brain-computer interface for makers. The company more than doubled its goal of raising $100,000 for its EEG platform and, as I write this, OpenBCI is preparing to ship its first run of finished products. Conor does a demo of the technology in the link below:
OpenBCI Demo by Conor Russomano
Recently, I had a chance to talk with OpenBCI co-founder Conor Russomanno to get his thoughts on how open source has changed the brain-computer interface (BCI) landscape and opened new opportunities in the present, and how it might affect future development opportunities as well.
“The one thing that we’re hoping to achieve with OpenBCI is to really lower the barrier of entry – both in terms of educational materials but also cost,” Russomanno said. “I think one really awesome implication is that, in a classroom or laboratory, where one research grade EEG system was used by a number students, now the same amount of money could be used to outfit every student with their own device. And we’ve seen that in our customer base, as a huge proportion of our customers are students, graduate-level researchers and professors who want to use OpenBCI as a learning tool.”
Another exciting change that OpenBCI is creating is an open source community that allows users and makers to connect and share their knowledge to take the technology even further, Russomanno noted. In fact, OpenBCI is dedicating a fair chink of its resources to create that community.
“Probably the quickest people to jump on the preorders and the Kickstarters were students and researchers who were already working with existing EEG devices. We are trying to get more people interested by creating a community, putting out instructional guides and making it more approachable.
“I like to think what we’re doing with OpenBCI as Lego meets EEGs. I think of what we’re building as not a finished product, but as a narrow building block. And we want the world to use these blocks to build the cool stuff,” he said.
While the success and acclaim OpenBCI has received in mainstream media has been exciting, as he looks at the opportunities for further development of open source BCI, Russomanno is cautiously optimistic. In my mentioning of some of the farther-reaching future implications of BCI technologies, Conor brought the conversation back to the present, seeming less interested in far away “what ifs” than in how the next step forward in research might be taken:
“I think its important to be realistic about what the technology is capable of,” he said. “There are still a lot of challenges and they’re not all going to be solved by the same company or by a single field of research. It’s important that people collaborate together, specialize and improve upon a small facet of the problem by sharing that information with someone else who has solved another small facet.
“What we’re trying to do with OpenBCI is to expose all of the weaknesses of the full system and say ‘Hey guys! Jump in! What can you do to improve this other piece?’”
Another hurdle Russomanno hopes open source BCI can bridge in the future is the gap between the enthusiastic expectations of the general public and the realistic limits of the current technology. While an enthusiastic hope of BCI might involve telepathic control of technology or complete conscious “embodiment” in a robotic form, the current reality of BCI is less “far out.” The calibration of today’s external BCI devices still involves a relatively slow process of attuning to individual brain patterns, and isn’t nearly at “telepathic” levels, although some researchers have been able to develop significant control of devices and games with EEG headsets.
“I think many people would agree that the ‘Holy Grail’ of practical, wearable EEG is a sensor. Right now, it’s very difficult to acquire a strong EEG signal from outside the scalp because you’ve got a lot of things that produce ‘noise,’” he continued. “I’m not sure if it will ever happen, but the one problem that needs to be optimized is the electrode problem. We’ve broken out the header pins so you can attach any electrode on, so if that Holy Grail does get found in the next one or two years, hopefully you’ll just be able to plug it right into the OpenBCI board.
“On the other end of the spectrum,” Russomanno continued. “Once you’ve got good spatial resolution, a high number of channels and a good quality of signal, what do you do with this data now that you’re collecting it? How do you classify this information to create a system that responds in a pre-determined way?
“That’s where software and research comes in. You’ve got electrical engineers that need to solve the electrode problem. But then you’ve got data analytics and programmers that need to work together to create algorithms that will classify massive amounts of data,” he noted.
Conor’s earlier comment about the interdisciplinary nature of BCI research starts to hit home, but he wasn’t done yet. After software challenges, there’s one more hurdle left for the full optimization of open source BCI, he added.
“Every brain is similar but every brain is unique. When it gets to that point where we’ve got enough systems producing enough data that it can be scaled cheaply from individual to individual, then it’s a matter of building an interface that’s user customizable that has enough flexibility to be able to refine its classification inputs to match the specific user.”
Ultimately, Russomanno says the mission for OpenBCI is to make the technology more accessible and that, wherever open source BCI goes in the future, a community based on cooperation and collaboration will take it there.
With so much to work on, he’s aiming to facilitate the global conversation necessary to bring BCI to the next level, without funding it all in his own proprietary lab. If all brains are unique, then we’ll learn more about calibrating devices by testing and tinkering with people all over the world. Conor’s aim, however, it not just to use their heads as experiments, but to generate new hypotheses to test and ideas to explore — expanding the field for everyone.
“Putting our heads together” takes on multiple literal interpretations here, and that’s how he intends it.
Conor ended our chat with come practical advice for researchers and makers who want to help the cause: “The best way for people to join that community is to acquire the technology, try to figure out how to make it work, be vocal on the forums and keep spreading the open source wildfire.”
While the “Ice Bucket Challenge” raised millions to fuel research toward a cure for
amyotrophic lateral sclerosis (ALS), there are a number of assistive technologies already at work to help those currently affected by the disease. According to Alisa Brownlee, a clinical manager for the ALS Association, more assistive technologies and brain-computer-interfaces are on the way. At present, the largest hurdle is access.
Brownlee noted that the loss of communication is often the hardest part of ALS for someone to endure. As ALS is a progressive disease, there are several forms of assistive technology that are used based on a given patient’s physical status. Each form of that technology will work for awhile, but then patients will have to move on to something else as the disease progresses, she says.
Using computer access as one way to help maintain an ALS patient’s communication skills, ALS patients can transition to a track-ball mouse and on-screen keyboard in lieu of a standard computer mouse. From there, a person can use a head-mount, eye-gaze system, and even a tablet computer with a switch scanner.
“It depends on which type of device the individual wants and their physical limitations when we are getting involved with them. They can go from the very simple to the very complex,” Brownlee said. “Technology is wonderful, but it’s not for everyone. So it’s important to involve the person, understand their personality and understand their coping mechanism dealing with the loss of communication.”
While it’s a significant improvement over what was available 10 or 20 years ago, this assistive technology has its limitations, Brownlee said. A system which requires the user to dwell over a letter to type, such as a head mouse, is pretty much limited to five to seven words a minute, which can be frustrating when the average adult speaks about 150 to 200 words a minute. Further, eye-gaze systems can’t be used in natural light by those with underlying eye issues, such as users with tri-focals, torn retinas, or pupils that are too dark; plus, they can be difficult to calibrate.
“That’s the one thing I hear from our caregivers all the time, ‘Hey we can’t get the thing to calibrate!’” she said. “It has to be 23 inches away from the user and, if your positioning is anything less than that, it gets real difficult. It’s just real frustrating.”
Looking to the future of assistive technologies, wearable technology such as Google Glass is already showing great promise in helping those with ALS and other disabilities communicate, Brownlee said. The Google Glass headset is easy to calibrate, can be used in any light, and can be accessed by its user whether they’re sitting up or laying in bed, she said.
Costing a fraction of a standard $15,000 eye-gaze system, Google Glass is more affordable option, Brownlee added. Though there are still some user interface problems that need to be addressed, new applications to make Google Glass even more accessible to those with disabilities are in the works..
“A colleague of mine is working on how to drive a powered wheelchair through Google Glass. Because ALS is a progressive disease, we have a lot of people who can not drive their wheelchairs anymore because they’ve lost the function in their hands,” Brownlee said. “If this comes to fruition, you could be able to drive your wheelchair through Glass. And this could open up a whole world for many people with disabilities. It could also make a huge financial burden much easier, so people with disabilities could afford technology, because right now, it’s unaffordable.”
The historical context in which Brain Computer Interfaces (BCI) has emerged has been addressed in a previous article called “To Interface the Future: Interacting More Intimately with Information” (Kraemer, 2011). This review addresses the methods that have formed current BCI knowledge, the directions in which it is heading and the emerging risks and benefits from it. Why neural stem cells can help establish better BCI integration is also addressed as is the overall mapping of where various cognitive activities occur and how a future BCI could potentially provide direct input to the brain instead of only receive and process information from it.
EEG Origins of Thought Pattern Recognition
Early BCI work to study cognition and memory involved implanting electrodes into rats’ hippocampus and recording its EEG patterns in very specific circumstances while exploring a track both when awake and sleeping (Foster & Wilson, 2006; Tran, 2012). Later some of these patterns are replayed by the rat in reverse chronological order indicating a retrieval of the memory both when awake and asleep (Foster & Wilson, 2006). Dr. John Chapin shows that the thoughts of movement can be written to a rat to then remotely control the rat (Birhard, 1999; Chapin, 2008).
A few human paraplegics have volunteered for somewhat similar electrode implants into their brains for an enhanced BrainGate2 hardware and software device to use as a primary data input device (UPI, 2012; Hochberg et al., 2012). Clinical trials of an implanted BCI are underway with BrainGate2 Neural Interface System (BrainGate, 2012; Tran, 2012). Currently, the integration of the electrodes into the brain or peripheral nervous system can be somewhat slow and incomplete (Grill et al., 2001). Nevertheless, research to optimize the electro-stimulation patterns and voltage levels in the electrodes, combining cell cultures and neurotrophic factors into the electrode and enhance “endogenous pattern generators” through rehabilitative exercises are likely to improve the integration closer to full functional restoration in prostheses (Grill et al., 2001) and improved functionality in other BCI as well.
When integrating neuro-chips to the peripheral nervous system for artificial limbs or even directly to the cerebral sensorimotor cortex as has been done for some military veterans, neural stem cells would likely help heal the damage to the site of the limb lost and speed up the rate at which the neuro-chip is integrated into the innervating tissue (Grill et al., 2001; Park, Teng, & Snyder, 2002). These neural stem cells are better known for their natural regenerative ability and it would also generate this benefit in re-establishing the effectiveness of the damaged original neural connections (Grill et al., 2001).
Neurochemistry and Neurotransmitters to be Mapped via Genomics
Cognition is electrochemical and thus the electrodes only tell part of the story. The chemicals are more clearly coded for by specific genes. Jaak Panksepp is breeding one line of rats that are particularly prone to joy and social interaction and another that tends towards sadness and a more solitary behavior (Tran, 2012). He asserts that emotions emerged from genetic causes (Panksepp, 1992; Tran, 2012) and plans to genome sequence members of both lines to then determine the genomic causes of or correlations between these core dispositions (Tran, 2012). Such causes are quite likely to apply to humans as similar or homologous genes in the human genome are likely to be present. Candidate chemicals like dopamine and serotonin may be confirmed genetically, new neurochemicals may be identified or both. It is a promising long-term study and large databases of human genomes accompanied by medical histories of each individual genome could result in similar discoveries. A private study of the medical and genomic records of the population of Iceland is underway and has in the last 1o years has made unique genetic diagnostic tests for increased risk of type 2 diabetes, breast cancer prostate cancer, glaucoma, high cholesterol/hypertension and atrial fibrillation and a personal genomic testing service for these genetic factors (deCODE, 2012; Weber, 2002). By breeding 2 lines of rats based on whether they display a joyful behavior or not, the lines of mice should likewise have uniquely different genetic markers in their respective populations (Tran, 2012).
fMRI and fNIRIS Studies to Map the Flow of Thoughts into a Connectome
Though EEG-based BCI have been effective in translating movement intentionality of the cerebral motor cortex for neuroprostheses or movement of a computer cursor or other directional or navigational device, it has not advanced the understanding of the underlying processes of other types or modes of cognition or experience (NPG, 2010; Wolpaw, 2010). The use of functional Magnetic Resonance Imaging (fMRI) machines, and functional Near-Infrared Spectroscopy (fNIRIS) and sometimes Positron Emission Tomography (PET) scans for literally deeper insights into the functioning of brain metabolism and thus neural activity has increased in order to determine the relationships or connections of regions of the brain now known collectively as the connectome (Wolpaw, 2010).
Dr. Read Montague explained broadly how his team had several fMRI centers around the world linked to each other across the Internet so that various economic games could be played and the regional specific brain activity of all the participant players of these games can be recorded in real time at each step of the game (Montague, 2012). In the publication on this fMRI experiment, it shows the interaction between baseline suspicion in the amygdala and the ongoing evaluation of the specific situation that may increase or degree that suspicion which occurred in the parahippocampal gyrus (Bhatt et al., 2012). Since the fMRI equipment is very large, immobile and expensive, it cannot be used in many situations (Solovey et al., 2012). To essentially substitute for the fMRI, the fNIRS was developed which can be worn on the head and is far more convenient than the traditional full body fMRI scanner that requires a sedentary or prone position to work (Solovey et al., 2012).
In a study of people multitasking on the computer with the fNIRIS head-mounted device called Brainput, the Brainput device worked with remotely controlled robots that would automatically modify the behavior of 2 remotely controlled robots when Brainput detected an information overload in the multitasking brains of the human navigating both of the robots simultaneously over several differently designed terrains (Solovey et al., 2012).
Writing Electromagnetic Information to the Brain?
These 2 examples of the Human Connectome Project lead by the National Institute of Health (NIH) in the US and also underway in other countries show how early the mapping of brain region interaction is for higher cognitive functions beyond sensory motor interactions. Nevertheless, one Canadian neurosurgeon has taken volunteers for an early example of writing some electromagnetic input into the human brain to induce paranormal kinds of subjective experience and has been doing so since 1987 (Cotton, 1996; Nickell, 2005; Persinger, 2012). Dr. Michael Persinger uses small electrical signals across the temporal lobes in an environment with partial audio-visual isolation to reduce neural distraction (Persinger, 2003). These microtesla magnetic fields especially when applied to the right hemisphere of the temporal lobes often induced a sense of an “other” presence generally described as supernatural in origin by the volunteers (Persinger, 2003). This early example shows how input can be received directly by the brain as well as recorded from it.
Higher Resolution Recording of Neural Data
Electrodes from EEGs and electromagnets from fMRI and fNIRIS still record or send data at the macro level of entire regions or areas of the brain. Work on intracellular recording such as the nanotube transistor allows for better understanding at the level of neurons (Gao et al., 2012). Of course, when introducing micro scale recording or transmitting equipment into the human brain, safety is a major issue. Some progress has been made in that an ingestible microchip called the Raisin has been made that can transmit information gathered during its voyage through the digestive system (Kessel, 2009). Dr. Robert Freitas has designed many nanoscale devices such as Respirocytes, Clottocytes and Microbivores to replace or augment red blood cells, platelets and phagocytes respectively that can in principle be fabricated and do appear to meet the miniaturization and propulsion requirements necessary to get into the bloodstream and arrive at the targeted system they are programmed to reach (Freitas, 1998; Freitas, 2000; Freitas, 2005; Freitas, 2006).
The primary obstacle is the tremendous gap between assembling at the microscopic level and the molecular level. Dr. Richard Feynman described the crux of this struggle to bridge the divide between atoms in his now famous talk given on December 29, 1959 called “There’s Plenty of Room at the Bottom” (Feynman, 1959). To encourage progress towards the ultimate goal of molecular manufacturing by enabling theoretical and experimental work, the Foresight Institute has awarded annual Feynman Prizes every year since 1997 for contribution in this field called nanotechnology (Foresight, 2012).
The Current State of the Art and Science of Brain Computer Interfaces
Many neuroscientists think that cellular or even atomic level resolution is probably necessary to understand and certainly to interface with the brain at the level of conceptual thought, memory storage and retrieval (Ptolemy, 2009; Koene, 2010) but at this early stage of the Human Connectome Project this evaluation is quite preliminary. The convergence of noninvasive brain scanning technology with implantable devices among volunteer patients supplemented with neural stem cells and neurotrophic factors to facilitate the melding of biological and artificial intelligence will allow for many medical benefits for paraplegics at first and later to others such as intelligence analysts, soldiers and civilians.
Some scientists and experts in Artificial Intelligence (AI) express the concern that AI software is on track to exceed human biological intelligence before the middle of the century such as Ben Goertzel, Ray Kurzweil, Kevin Warwick, Stephen Hawking, Nick Bostrom, Peter Diamandis, Dean Kamen and Hugo de Garis (Bostrom, 2009; de Garis, 2009, Ptolemy, 2009). The need for fully functioning BCIs that integrate the higher order conceptual thinking, memory recall and imagination into cybernetic environments gains ever more urgency if we consider the existential risk to the long-term survival of the human species or the eventual natural descendent of that species. This call for an intimate and fully integrated BCI then acts as a shield against the possible emergence of an AI independently of us as a life form and thus a possible rival and intellectually superior threat to the human heritage and dominance on this planet and its immediate solar system vicinity.
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