The limitations of cognitive enhancement drugs will soon be complemented and surpassed by brain machine interfaces. The most consumer accessible brain machine devices that provide some intellectual enhancement are neurofeedback and transcranial direct current stimulation. Genetic and tissue engineering may provide avenues for at least the repair of cognitive deficits, and perhaps enhancement. Progress in actual nano-neural brain-machine interfaces, which will require advances in miniaturization, materials and nanotechnology, will enable more profound enhancement.
In this series:
There are a number of promising brain-machines interfaces for boosting intelligence.
Neurofeedback Consumer EEG neurofeedback tools, such as the Muse, Melon and iFocusBand tools released this year, are now quite affordable. They allow the monitoring and, theoretically, entrainment of states of focus. Clinical experiments attempting to improve cognitive functions with neurofeedback have been going on for decades. Hopefully these new headsets, since they can be worn for hours every day, will demonstrate more benefits for improving cognitive functioning than the neurofeedback used in brief clinical experiments so far. Dozens of studies have reported neurofeedback improving attention, executive function, memory and intelligence. But they often lack placebo controls, and several careful meta-analyses of studies of the benefits of neurofeedback for ADD have not yet demonstrated a significant benefit in improving attention, executive functioning or memory.   
Magnetic Stimulation It is ironic that evidence is showing that magnetism and electricity can improve cognition considering the enthusiasm for quack electric and magnetic therapies in the 18th and 19th century. Transcranial magnetic stimulation (TMS) involves temporarily depolarizing neurons in the brain with large electromagentic coils. Since the effects are temporary and require large, expensive machines that can’t easily be miniaturized the utility of TMS for general cognitive enhancement is very limited. But the effects that have been achieved with a couple sessions under the device have been remarkable.
Reports that TMS speeded response time and improved memory began to be published twenty years ago as soon as the technique was invented. One way that this occurs is by stimulating the release of nerve growth factor (BDNF), and increasing the size of the brain region it is focused on. For instance focusing the magnets on the hippocampus, the seat of memory, enhances recall and after a couple of sessions begins to increase the size of the hippocampal network. TMS can also speed up cognition by suppressing distractions, the “addition by subtraction” mechanism, unlocking creativity and savant-like mathematical and spatial visualization abilities. TMS is being explored in remediating cognitive deficits in dementias and stroke, and as a treatment for epilepsy, migraines and tinnitus.
Zapping Your Head Transcranial direct current stimulation (TDCS), passing low levels of current directly through the scalp, has also been found to have a number of cognitive benefits, from improving learning and memory to improving math and language skills, depending on which part of the brain is stimulated. As with TMS, TDCS is being explored as a therapy to repair cognitive deficits from dementias, depression, schizophrenia and other mental disorders. A 2014 review of research looking at military applications concluded “TDCS has been shown to accelerate skill acquisition in tasks representative of surveillance and security operations, intelligence analysis, and procedural learning in complex monitoring.” For instance soldiers learned to identify targets faster with TCDS.
In one startling study researchers gave 33 subjects a problem that involved linking nine dots with four or fewer straight lines. Without TDCS none of the subjects could solve the puzzle, but while having their brains zapped with TDCS 40% (14) of them were able to solve the puzzle.
One concern has been that the learning acquired under TCDS may not generalize as well later. On the other hand one recent study found that significant improvements in math skills from TDCS could still be detected six months later.
TDCS is of far more practical utility as a cognitive enhancement method than TMS since it only requires inexpensive equipment that can easily be worn on the head for extended periods, and is already available to consumers in the $250 foc.us headset (shown above). But researchers are alarmed by the eager lay experimentation with TCDS. TDCS is safer than TMS, with fewer reported side effects, but since so many more people will be experimenting with TMS for long periods unsupervised at home, while TMS is applied in controlled doses in a laboratory setting, the number of those adverse side effects will be commensurably larger.
Deep Brain Stimulation (DBS) , Brain Machine Interfaces (BCI) and Memory Prosthetics Zapping the brain with magnetism or electricity through the skull is, of course, a very crude way to manipulate intelligence, despite its promise. Soon we will have ways to directly manipulate, augment and communicate with the brain that will provide exponentially more enhancement of thinking, memory and learning.
In the 1960s we began treating deafness by implanting electrodes in the cochlea to transmit sound to the cochlear nerves, and more than 200,000 people now have cochlear implants around the world. Since the 1990s we have been implanting electrodes in brains, “brain pacemakers” or “deep brain stimulation” (DBS), to treat a variety of disorders, and now more than 100,000 people have received DBS implants. The US FDA has approved DBS as a treatment for obsessive-compulsive disorder, tremors and Parkinsons disease, and it is being used a treatment for depression, Tourette syndrome and chronic pain, although not yet as an FDA-approved therapy. Research is now being pursued in using DBS to stimulate memory and cognitive functions in people with dementia.
For two decades we have also been implanting computer chips in the brains of completely paralyzed human subjects, “brain-computer interfaces” (BCIs), and teaching them to communicate through those chips. Primates and human research subjects with these chips have been able to manipulate computer cursors, and virtual and physical prostheses.
Another BCI soon to be available is the memory prosthesis - basically an artificial hippocampus – already demonstrated in primate models, and now being developed for the treatment of dementia and severe brain trauma. In the coming decades we will have increasingly sophisticated brain prostheses to repair and then enhance all the parts of the brain, including the parts the enable our virtues such as intelligence.
One big problem with these therapies currently is that they require opening the skull, which can have major complications, and then placing something in the brain that doesn’t play well with neurons over time. Eventually electrodes get encapsulated by protective tissue, the “foreign body response,” that separate them from the surrounding neurons. This isn’t as big a problem for electrodes that simply need to zap that region of the brain to prevent tremors or a seizure, or to short-circuit depression. But preventing encapsulation is critical for the recording electrodes attached to brain-machine interfaces trying to pick up signals from neighboring neurons. Anti-inflammatory coatings are being developed for electrodes that camouflage them from the brain’s defensive responses.
In order to make BCIs something useful for the ordinary person instead of a desperate and dangerous measure for those with no alternative, we need to make them a lot smaller, get them into the brain without surgery, and have them generate their own power. That will require progress with nanorobots able to traverse the blood-brain barrier and power themselves organically, navigate their way to the appropriate parts of the brain, and establish a network of communication between neurons and computers outside the skull. In other words, they need to a hybrid of biological microorganisms, computers and robots, which is certainly more than a decade away yet.
But we are getting closer. Recently a team at Berkeley developed a wireless brain interface that they call “neural dust.” Each sensor is about the thickness of a hair, and although they would require opening the brain to implant, thousands of them could be implanted along with transceiver, and then the brain closed. The transceiver powers the sensors with ultrasound, picks up their neural signals and transmits the signals to an external computing device.
Changing the Brain
Neurogenesis and Cleaning Out Neural Junk As Melanie Swan discussed recently in “Nanomedical Cognitive Enhancement”, two promising avenues for cognitive enhancement are the promotion of neural cell growth and elimination of neural junk. As mentioned earlier, exercise and methylphenidate stimulate neural growth, and the search is on for neurotrophic drugs that will also do so. Teams are also developing introducing nanomaterials that provide a scaffolding for new neurons to grow on, which could be helpful in repairing spinal cord injuries for instance.
Another avenue for improving cognitive function is the elimination of the junk that accumulates in the brain, principally beta-amyloid protein plaques and fatty deposits of lipofuscin which are implicated in dementias and other neurological diseases. These deposits could be targeted with drugs and eventually with nanomachines.
Gene therapy As I discussed earlier there is no one IQ gene. But that is not to say that there are not single genes which, if manipulated in unusual ways, might not have dramatic effects on intellectual ability. In one recent startling experiment researchers at Yale turned off the Nogo receptor gene, which suppresses neural plasticity in adult mice. By doing so they restored adult mice to juvenile levels of plasticity. Suppressing the Nogo gene is now being explored as a way to encourage brain repair after stroke. We will probably discover more individual genes that are not related to variations in intelligence when functioning ordinarily, but that when manipulated unlocked cognitive potentials.
Reforming the Regulation of Cognitive Enhancement
At the level of social policy we need to reform the regulatory restrictions holding back research on, and equitable access to, cognitive enhancement therapies. Currently no insurance company or public health system considers a prescription of a cognitive enhancer for a healthy person to be legitimate. As a consequence almost all cognitive enhancement research is targeted at therapies for attention deficit disorder, dementia, Downs and mental illness, with studies of their effects on healthy adults the rare spin-offs. Formally including cognitive enhancement for healthy people in the neuroscience research agenda would illuminate many of the cost-benefit questions that trouble critics and advocates alike, making clear who really benefits and what the trade-offs are.
Legalizing cognitive enhancement as a legitimate prescription would likewise have a beneficial effect on society. Currently affluent people are more likely to be able convince physicians to prescribe cognitive enahncement drugs for themselves and their children, or they can buy the drugs illegally, and that exacerbates the cognitive inequity in society. If public health systems permitted prescriptions of cognitive enhancment drugs those with lower intelligence and non-pathological levels of cognitive impairment would be more likely to benefit than those on the other end of the spectrum, reducing cognitive inequality.
The Obligation to Be More Intelligent and the Dangers of Imbalanced Intelligence
The principal points of this section are that
- we have a moral obligation to be as intelligent as possible;
- that intellectual virtues have applications in the prudential exercise of all the other virtues – self-control, intelligent happiness choices, social intelligence, fairness and “spiritual intelligence”;
- that there are numerous social policies and individual lifestyles choices that we can pursue to improve general intelligence;
- and that our biological constraints require that we begin to tinker with the brain to achieve more optimal levels of intelligence.
But too much intelligence, unchecked by the other virtues, can also have its drawbacks. Excessive amounts of cognitive enhancing stimulants can overstimulate dopamine and norepinephrine, and impair learning, memory and neural plasticity; we need to exercise cognitive enhancement prudentially. Enhancement of social intelligence or cognitive empathy has to be accompanied by emotional empathy and a sense of moral constraint, since boosting cognitive empathy in psychopaths simply makes them better at exploiting others. Too much deliberation can be debilitating, as demonstrated by Antonio Damasio’s research on people unable to make decisions when brain damage prevents their access to emotions; deliberation without a sense of the value and weight of decisions can run endlessly. Deliberation uninformed by moral sentiments can lead to perversely machine-like moral decision-making. In the extreme, as Nick Bostrom illustrates in Superintelligence: Paths, Dangers, Strategies, too much artificial or human intelligence unchecked by moral self-control and social accountability could be catastrophic for society. The intellectual virtues need to find their own golden mean, and be tempered and entrained by self-control, empathy and fairness.
CEO Ariel Garten wearing the Muse headband
Brain machine interfaces
Beta Amyloid plaques
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