Sunday 30 September 2012

Brain Implants, a brief history and possible future

When you talk about brain implants the words conjure up an invasive surgical procedure of  cutting open the skull to allow electrodes of some kind. Technology now provides miniaturization and better interfaces between mind and machine. But without research there never would be the possibility to regain sight or hearing or cure certain diseases, I consider past exploits to predict the future of brain implants.
Historically in1870, Eduard Hitzig and Gustav Fritsch demonstrated that electrical stimulation of the brains of dogs could produce movements. Robert Bartholow showed the same to be true for humans in 1874. By the start of the 20th century, Fedor Krause began to systematically map human brain areas, using patients that had undergone brain surgery. Prominent research was conducted in the 1950s. Robert G. Heath experimented with aggressive mental patients, aiming to influence his subjects' moods through electrical stimulation.
Yale University physiologist Jose Delgado demonstrated limited control of animal and human subjects' behaviours using electronic stimulation. He invented the stimoceiver or transdermal stimulator, a device implanted in the brain to transmit electrical impulses that modify basic behaviours such as aggression or sensations of pleasure. Delgado was later to write a popular book on mind control, called Physical Control of the Mind, where he stated: "the feasibility of remote control of activities in several species of animals has been demonstrated  The ultimate objective of this research is to provide an understanding of the mechanisms involved in the directional control of animals and to provide practical systems suitable for human application."
In the 1950s, the CIA also funded research into mind control techniques, through programs such as MKULTRA. Perhaps because he received funding for some research through the US Office of Naval Research, it has been suggested (but not proven) that Delgado also received backing through the CIA. He denied this claim in a 2005 article in Scientific American describing it only as a speculation by conspiracy-theorists. He stated that his research was only progressively scientifically-motivated to understand how the brain works.
The end of cold war and psychosurgery in decline due to the introduction of new drugs and a growing awareness of the long-term damage caused by the operations as well as doubts about its efficacy. Brain implants seemed to be tarnished with the idea of thought control and thought manipulation.
The Food and Drug Administration (FDA) approved Deep Brain Stimulation  (a surgical treatment involving the implantation of a medical device called a brain pacemaker, which sends electrical impulses to specific parts of the brain), as a treatment for essential tremor in 1997, for Parkinson's disease in 2002, and dystonia in 2003. DBS is also routinely used to treat chronic pain and has been used to treat various affective disorders, including major depression. While DBS has proven helpful for some patients, there is potential for serious complications and side effects.
Mean while recently, scientists have demonstrated that a brain implant can improve thinking ability in primates. By implanting an electrode array into the cerebral cortex of monkeys, researchers were able to restore and even improve  their decision-making abilities. The implications for possible therapies are far-reaching, including potential treatments for cognitive disorders and brain injuries. But there's also the possibility that this could lead to implants that could boost your intelligence.
Researchers from Wake Forest Baptist Medical Centre, University of Kentucky, and University of Southern California took five rhesus monkeys and trained them on a delayed match-to-sample task.
Once they were satisfied that the correct mapping had been done, they administered cocaine to the monkeys to impair their performance on the match-to-sample task (seems like a rather severe drug to administer, but there you have it). Immediately, the monkeys' performance fell by a factor of 20%. It was at this point that the researchers engaged the neural device. Specifically, they deployed a "multi-input multi-output nonlinear" (MIMO) model to stimulate the neurons that the monkeys needed to complete the task. The inputs of this device monitored such things as blood flow, temperature, and the electrical activity of other neurons, while the outputs triggered the individual neurons required for decision making. Taken together, the i/o model was able to predict the output of the cortical neurons — and in turn deliver electrical stimulation to the right neurons at the right time.
The researchers successfully restored the monkeys' decision-making skills even though they were still dealing with the effects of the cocaine. Moreover, when duplicating the experiment under normal conditions, the monkeys' performance improved beyond the 75% proficiency level shown earlier. In other words, a kind of cognitive enhancement had happened.  While in June 2011, Second Sight received CE mark of approval for the Argus II Artificial eye meaning for £53,000 you can now buy the system. It is the first bionic eye to be approved for sale anywhere in the world.
And Zheng Xiaoxiang of the Brain-Computer Interface Research Team at Zhejiang University in Zijingang, China, and colleagues announced that they had succeeded in capturing and deciphering the signals from the monkey's brain and interpreting them into the real-time robotic finger movements.
More successfully Braingate pioneer Professor John Donoghue said they had implanted an aspirin-sized electrode array on to the patients’ motor cortex – the part of the brain that controls movement. The technology is a neural interface system called BrainGate2, currently in clinical trials, which connects Cathy’s brain to a robot. The device is the result of over 10 years of research at Brown University and an extension of the first BrainGate in 2006, which allowed patients to control a computer cursor on a screen. Despite early attempts to control the human mind using Psychosurgery for controlling mental disorder, early research proved helpful to map out the human brain. But only recent experiments proved success with implants for brain machine interfacing. Even today an artificial eye has limited resolution and connections to the motor cortex can perform slow maneuvers.
Further research and miniaturization of electronics would ensure sophisticated bio electrical connections. Emerging technologies such as flexible circuity, which can operate within the body. Research at MIT has produced a fuel cell that could power small neural implants with the same source of energy as the brain itself: glucose. Engineers created a fuel cell that breaks down the ubiquitous sugar molecule much the same way as the body does, and it could enable a new generation of self-sustaining medical devices.
The project, led by MIT associate professor Rahul Sarpeshkar, was created with brain implants in mind, with the fuel cell tapping the glucose-rich cerebrospinal fluid that surrounds the brain and fills its cavities. And it's designed to allow electronics to be connected easily, as the fuel cell is itself embedded on a silicon chip that could easily be modified for different applications. The power it generates isn't much: up to 180 microwatts per square centimeter at maximum, but only a modest 3.4 microwatts can be counted on for a steady current. That's not nearly enough to power something like a laptop, but the team says that for a tiny implant that only needs to activate a few key cells, it should be sufficient. Sarpeshkar has written an entire book on ultra-low-power bioelectronics, so it's more than an educated guess. Boosted intelligence better communications with artificial limbs, even a bio- wifi is suggested in amongst the wide claims of what the future of implants can do. The future is no doubt a higher resolution of connectivity between man and machine. But I sometimes think that there will be a hidden cost and as we embrace technology we drift away from one another...

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