The human brain is one of the final frontiers for technological discovery. Picture a future where paralysis occurring from spinal cord injuries is only a brief restriction, rather than a permanent state.
Picture artificial limbs that can transmit the user feedback about how hot or cold their cup of coffee is, or simply how tightly they are holding their loved one’s hand. Picture a future where temporary implants can help an individual recover from a stroke or manage other debilitating neurological infirmities.
Now, all of these apparently impossible medical uses of new technology stand to be within reach for bi-directional brain-computer interfaces.
ARM and the Center for Sensorimotor Neural Engineering (CSNE) have signed an agreement whereby the CSNE will produce a bizarre brain-implantable system-on-a-chip (SoC) for bi-directional brain-computer interfaces (BBCI) aimed at determining neurodegenerative disorders.
Based at the University of Washington, the CSNE is a National Science Foundation engineering research centre operating to develop innovative ways to connect a deep computational perception of how the brain adjusts and processes data with the design of implantable devices.
The research project will enable us to start solving real world health obstacles with brain-implantable chips intended at tackling a pontoon of debilitating neurodegenerative disorders, including Parkinson’s disease, Alzheimer’s disease, and even paralysis.
The long-term purpose is to help people afflicted by neurological infirmities, by designing neurotechnology that will help the body heal, feel and move again.
The new SoC will play an important role in decoding the complex beacons formed inside the brain, digitising them so they can be processed and acted upon, with the end outcome of controlling the body’s muscle functions, which is the key to tackling the neurodegenerative disease.
Brain-implantable chips need to be extremely small, very power-efficient and able. The industry-proven ARM Cortex-M0 processor, the smallest ARM processor-accessible, will contribute to this extremely important area of investigation by being an essential component of the CSNE’s brain-implantable SoC.
The project is a natural fit for ARM and the concept of improving lives throughout the globe by developing a smarter, happier and healthier world with technology. It’s the continuing aim of improving the power efficiency of ARM products aligned with CSNE’s advanced research work in promoting low-power, effective and implantable neural devices for medical purposes.
The BBCI chip is being created to address stroke, spinal cord injury, and other neurological infirmities. People who have experienced a stroke or spinal cord trauma usually have health problems, such as paralysis, which can affect their quality of life by stopping them from moving parts of their body, for instance, a hand or an arm.
The research project will create a SoC which is capable of taking neural signals from the brain that interpret movements the person with paralysis wants to make, before delivering those signals to a stimulator inserted in the spinal cord itself.
This will allow the person to make the desired movements when they want to, dramatically overcoming their paralysis. In the future, the device will also be capable of transmitting information in the opposite direction, enabling the person to once again feel what their hand is touching.
Research is further showing that use of such a system may eventually aid to manipulate brain neurones to rewire in ways that help the brain recover from a stroke. The result of this BBCI collaboration is the development of neural devices that will help people by restoring sensation, limb function and increasing the brain’s innate restorative abilities.
In March 2008, a team of American scientists announced a method they had devised for calculating what somebody is looking at, simply by examining a study of their brain as they look at it. The studies were conducted on an MRI (magnetic resonance imaging) device, the likes of which is seen in hospitals everywhere, and their announcement provoked a debate about if scientists will someday be able to observe people’s dreams and thoughts like movies, and of all the privacy concerns that possibility raises.
The story captures one of the scientific and moralistic perplexities of our time. Courts are now allowing neuroscientific evidence, and a new discipline, neurolaw, has been born. Although numerous lawyers and neuroscientists remain dubious.
One possible obstacle is that, if researchers are to form useful conclusions regarding how the brain operates, they must be certain that a section that lights up in an individual brain scan is the equivalent section that lights up in numerous other people’s brain scans under the identical conditions.
However, the anatomical maps they have relied on for so long for determining those areas are no longer up to the task. For one thing, they tend to come in two dimensions, whilst MRI pictures come in three. For another, they don’t take into account the great variability between brains.
For the last 30 years, Karl Zilles, Katrin Amunts, and others at the Jülich Research Centre in Germany have been creating a 3D map of the brain that they believe will resolve this dilemma. It separates the brain up according to boundaries between specialised cell groups, based on computer study of brain tissue slices seen under a microscope.
They equate their conclusions over at least 10 brains, to deal with the different variability problem, and they call the result a probability map. They’ve covered almost half of the brain to date and expect to execute the project inside five years.
Even if scientists can meet a distinct pattern of brain activity with a particular visual stimulus, that doesn’t tell them much about how the person experiences that stimulus. Scientists now know that what a person sees is not just a representation of the world, but a reconstruction of it that is formed by their own experience and expectations.
The same is likely to be true of all perception. Take the concept of time, whilst all investigated human societies use a spatial analogy to represent time, not all of them think of the future as in front of them and the past behind.
A few of them, the Aymara of the Andes, for instance, look forward to the past.
Do we have free will? Now that the courts have opened their doors to neuroscience, they are being forced to rethink the proposal, fundamental to the dispensation of justice in most cultures, that human beings have free will.
The notion that we are kind, intentional individuals has been eroded by insights from genetics, such as the finding in 2002 by Avshalom Caspi of the Institute of Psychiatry, King’s College London, and others, that men with a particular variant of a gene encoding the enzyme monoamine oxidase-A, who had been abused as kids, were more inclined to show rebellious behaviour than men with comparable backgrounds who had a different variant of the gene.
The central focus of the free will dispute, nevertheless, continues to be a simplistic experiment that was conducted 25 years ago by Benjamin Libet at the University of California, San Francisco. Libet told people to raise their finger when they felt like it, and, crucially, to tell him when they felt that urge, whilst he observed their brain activity.
It was already understood that a shift in brain activity happens promptly before a person makes a spontaneous movement, however, Libet’s surprising finding was that that shift happened 300 milliseconds before people reported the desire to act.
We believe we are making a decision when, in fact, our brain has already made that decision. Our experience of making a decision at that instant is, consequently, an illusion. Furthermore, if we are deluded into believing that we are making choices, then we are further deluded into believing that we have free will.
Genetics is starting to cast light on the obscure notion of intellect, too. In November 2007, Robert Plomin and his associates at the Institute of Psychiatry, London identified six genes that appeared to be strongly linked with high or low intelligence in a sample of 7,000 seven-year-olds.
Even joined together, their results alone accounted for 1% of the variability in intelligence in that group.
Sleep is another puzzle researchers continue to try to unwind. Why do we do it? The current view is that sleep-related brain activity reactivates synapses or links connecting brain cells that were formed or reinforced throughout the day, the neural process that is believed to underlie learning and the development of memories.
However, at least one researcher has the opposing viewpoint.
Giulio Tononi of the University of Wisconsin thinks that sleep helps to prune back synapses, which are energetically costly to maintain, therefore ensuring that the brain remains affordable in energy terms.
Tononi doesn’t believe sleep has a particular purpose, however, he does think it may have just one core point. The basis for thinking that is that each animal sleeps. There is no exception.
Our bodies regulate sleep in much the same way that they control eating, drinking, and breathing. This implies that sleep serves a similarly important part in our well-being. While it is hard to answer the question, on why we sleep, scientists have uncovered several ideas that collectively may further justify why we consume a third of our lives sleeping.
Understanding these theories can further expand our appreciation of the purpose of sleep in our lives.
Whilst we may not often speculate about why we sleep, most of us accept at some level that sleep makes us feel better. We appear more bright, more active, content, and better prepared to function following a good night of sleep.
Nevertheless, the evidence that sleep makes us feel better and that going without sleep makes us feel worse only begins to illustrate why sleep might be important.
One way to think about the purpose of sleep is to match it to another of our life-sustaining activities, eating. Hunger is a shielding device that has developed to ensure that we eat the nutrients our bodies need to develop, rebuild tissues, and function well.
Also while it is comparatively straightforward to grasp the purpose that eating serves, given that it involves actually consuming the things our bodies require, eating and sleeping are not as diverse as they might appear.
Both eating and sleeping are controlled by strong internal forces. Going without food creates the annoying feeling of appetite whilst going without sleep makes us feel overwhelmingly tired. Furthermore just as eating reduces appetite and ensures that we get the nutrients we require, sleeping reduces tiredness and ensures that we get the sleep we need.
However, the question lingers, why do we require sleep at all? Is there a particular main purpose of sleep, or does sleep serve multiple roles?
Scientists have examined the question of why we sleep from several distinct perspectives. They have observed, for instance, what occurs when humans or other animals are stripped of sleep. In other studies, they have studied sleep patterns in a diversity of organisms to understand if comparisons or variations amongst species might reveal anything about sleep’s functions.
However, despite decades of investigation and numerous findings of other aspects of sleep, the mystery of why we sleep has been hard to acknowledge.
The absence of a definite response to this challenging problem does not suggest that this investigation has been a waste of time. In fact, much more is known about the purpose of sleep, and scientists have developed numerous encouraging opinions to demonstrate why we sleep.
In light of the evidence that has been found, it appears likely that no single opinion will ever be verified accurately. Rather, it may be found that sleep is explained by two or more of these explanations. The hope is that by better understanding why we sleep, we will learn to value sleep’s functions more and experience the health advantages it provides.
One of the earliest hypotheses of sleep sometimes termed the adaptive or evolutionary theory, implies that inactivity at night is an adaptation that served a survival role by keeping organisms out of harm’s way at times when they would be especially unprotected.
The hypothesis implies that animals that were able to stay still and quiet throughout these periods of vulnerability had an advantage over other animals that remained active. These animals did not have accidents throughout activities in the dark, for instance, and were not killed by predators.
Through natural selection, this behavioural approach probably developed to become what we now know as sleep.
A simple counter-argument to this argument is that it is always safer to remain awake in order to be able to respond to an emergency, even if lying still in the dark at night. Therefore, there does not appear to be any advantage of being unconscious and asleep if safety is paramount.
While it may be less obvious to people living in cultures in which food sources are abundant, one of the strongest factors in natural selection is striving for an effective utilisation of energy supplies. The energy conservation theory implies that the primary purpose of sleep is to decrease an individual’s energy demand and expenditure during part of the day or night, particularly at times when it is least effective to hunt for food.
Research has revealed that energy metabolism is significantly decreased throughout sleep, by as much as 10 percent in humans and even more in other species. For instance, both body temperature and caloric demand lower through sleep, as opposed to wakefulness.
Such evidence corroborates the hypothesis that one of the primary purposes of sleep is to help organisms preserve their energy supplies. Numerous scientists view this theory to be related to, and part of, the inactivity theory.
Another reason for why we sleep is based on the long-held notion that sleep in some way helps to renew what is expended in the body whilst we are awake. Sleep gives a chance for the body to rebuild and restore itself.
In recent years, these concepts have won backing from empirical evidence obtained in human and animal investigations. The most prominent of these is that animals stripped solely of sleep lose all immune function and die in simply a matter of weeks.
This is additionally bolstered by findings that many of the important restorative roles in the body like muscle growth, tissue replacement, protein structure, and growth hormone release happen often, or in some instances simply, throughout sleep.
Other rejuvenating aspects of sleep are specific to the brain and cognitive function. For instance, whilst we are awake, neurones in the brain generate adenosine, a by-product of the cells’ activities.
The build-up of adenosine in the brain is believed to be one factor that points to our understanding of being tired. Incidentally, this feeling is invalidated by the use of caffeine, which prevents the effects of adenosine in the brain and keeps us alert.
Scientists believe that this build-up of adenosine throughout wakefulness can help the drive to sleep. As long as we are conscious, adenosine accumulates and remains raised. During sleep, the body has a chance to clear adenosine from the system, and, as a consequence, we feel more alert when we wake.
One of the most current and compelling explanations for why we sleep is based on conclusions that sleep is related to alterations in the composition and structure of the brain. This wonder, identified as brain flexibility, is not fully known, however, its relationship to sleep has many significant implications.
It is growing obvious, for instance, that sleep plays a crucial part in brain growth in babies and young children. Babies consume approximately 13 to 14 hours per day sleeping, and around half of that period is used in REM sleep, the stage in which most dreams happen.
A connection between sleep and brain flexibility is growing apparent in grown-ups as well. This is observed in the impact that sleep and sleep loss have on people’s capacity to learn and accomplish a diversity of tasks.
While these hypotheses remain unproven, science has made great strides in exploring what occurs throughout sleep and what mechanisms in the body regulate the sequences of sleep and wakefulness that help determine our lives.
Whilst this research does not directly clarify the question, why do we sleep? it does set the platform for putting that question in a new context and producing new information regarding this vital part of life.