Imagine for a second feeling “overcomplete.” You have all of your limbs, and they are perfectly healthy. Yet, you feel as though your leg doesn’t belong to you. It shouldn’t be there, and you know it needs to go. The only way you can feel “whole” again is through its removal. You might be wondering why anyone would want to get rid of a perfectly healthy limb. Well, this phenomenon is the result of apotemnophilia, or Body Integrity Identity Disorder (BIID), a condition characterized “by the intense and long-standing desire for the amputation of a specific limb.” Most know exactly where they want the line of amputation to be, and this place stays fairly constant as time passes. Since it is rare for a surgeon to agree to amputate a healthy limb, many suffering from this condition will unfortunately resort to attempting the amputation themselves. In the past, this rare disorder was thought to be only psychological, and that perhaps the yearning for amputation was simply a way of seeking attention. However, in recent years, studies have shown otherwise.
One study performed by David Brang, Paul D. McGeoch and Vilayanur S. Ramachandran suggests that apotemnophilia is indeed a neurological disorder. The otherwise healthy subjects of the study went through a series of blind skin conductance response tests where they were pinpricked above and below the line where the amputation was. The responses to the pinpricking below the line were much greater than those above it. The resulting differences found suggest some abnormalities with the somatosensory input to the body part in question.
They suspect the disorder to be a consequence of damage to the right parietal lobe, which is responsible for processing sensory input from certain areas and forming our sense of body image. It could be the dysfunction within the right parietal lobe, specifically the right superior parietal lobe, causing irregular sympathetic output. The discrepancy between the signals and body image can lead to the feeling that a certain limb doesn’t belong and should be removed in order to feel “complete.” In addition, most patients have dealt with these feelings since childhood suggesting that the dysfunction is congenital.
Tobacco use is widely considered to cause more preventable and premature deaths than any other factor in developed countries. In other words, a successful campaign against tobacco use would arguably save more lives globally than any other campaign for public health.
There are many different ways of consuming tobacco, but for the purposes of this paper only cigarette smoking will be discussed and will be referred to simply as “smoking.” It is well known that smoking causes a variety of serious negative health effects; all one has to do is look at the warning label on a box of cigarettes. Why then, in spite of the obvious dangers, do so many people continue to smoke? One reason is simply because smoking looks cool, mainly due to its glorification in popular culture. In a more recent phenomenon, it seems that lower numbers of smokers in the population have given smoking a unique, hipster image. While an important one, image is not the only factor preserving smoking’s popularity; the main factor can only be fully understood through neuroscience. It is a specific process occurring within the brain called addiction, or more technically drug dependence.
Google, IBM, Microsoft, Baidu, NEC and others use deep learning and neural networks in development of their most recent speech recognition and image analysis systems. Neural networks have countless other uses, so naturally there are tons of startups trying to use neural networks in new ways. The problem being faced with now, is how exactly to implement neural network models in a way that mimics the circuitry of the brain. Brains are highly parallel and extremely efficient; the ultimate achievement of a neural network model would be able to perform large scale parallel operations while being energy efficient. Current technology is not well suited for large-scale parallel processing, and it is nowhere near as efficient as our brain, which uses only 20 watts of power on average (a typical supercomputer uses somewhere along the order of several megawatts of electricity).
One way in which future computers could mimic the efficiency of the brain is being developed by IBM. IBM believes that energy efficiency is what will guide the next generation of computers, not raw processing power. Current silicon chips have been doubling in power through Moore’s Law for almost half a century, but are now reaching a physical limit. To break through this limit, researchers at IBM’s Zurich lab headed by Dr. Patrick Ruch and Dr. Bruno Michel want to mimic biology’s allometric scaling for new “bionic” computing. Allometric scaling is when an animal’s metabolic power increases with its body size; the approach taken by IBM is to start with 3D computing architecture, with processors stacked and memory in between. In order to keep everything running without overheating, this biologically-inspired computer would be powered, and cooled, by so-called electronic blood. Hopefully this fluid will be able to multi-task, and like blood supplies sugar while taking away heat, accomplish liquid fueling and cooling at the same time.
Do you fancy yourself a scientist? Are you unable to work in a laboratory? Now with online crowd sourcing technology, you can be on the front line of cutting-edge discoveries. In the same fashion that people raise money through crowd sourcing on websites like KickStarter and GoFundMe, researchers at MIT have created a program to capitalize on the thousands of people that have access to a computer. The project is headed by Dr. Sebastian Seung using data collected from the Max Planck Institute for Medical Research. The goals of the project are to reconstruct the three-dimensional shapes of retinal neurons from two-dimensional images, to identify synapses in order to map the connections between neurons, and to relate this connectivity with the known activity of the neurons. Completion of these tasks will contribute to the overall goal of developing the connectome, a project with the same ideal of the Human Genome Project, but for neural connections instead of genes.
Currently, Eyewire is mapping four types of cells: amacrine, bipolar, ganglion, and glial cells. Many processes are used to map these cells. First, cells are photographed using serial block-face scanning electron microscopy (SBFSEM). This technique uses two groups of materials to stain a sample. The heavy metals osmium, lead, and uranium are used and an epoxy resin, or a type of plastic, are combined to produce a sample that can easily be read by a scanning electron microscope (SEM). The heavy metals react with a focused beam of electrons coming from the SEM to create a high resolution two dimensional image. A three dimensional image is created by combining layers of the sample, with each layer being about 70 microns thick.
Huntington’s disease, a neuro-degenerative disorder, affects roughly 5-10 out of every 100,000 people. The disease acts by deteriorating many structures in the brain, beginning with the Caudate Nucleus, which is involved in motor control. By the end of their lives, patients are expected to lose about 30% of their brain mass.
In the last few decades much has been learned about the disease: we now know that it’s genetic, caused by a mutation on the 4th chromosome, and leads the ‘so-called’ huntingtin protein to grow too long and fold in on itself incorrectly. Parents with Huntington’s disease each have a 50% chance of passing it on to their child. Symptoms usually appear between 35 and 45 years of age, and the life expectancy after the first appearance of symptoms is 10-20 years. There currently is no treatment for Huntington’s itself, so patients can only receive a little bit of relief from their symptoms while the disease progresses.
So far, there is no real consensus among scientists about how exactly the disease works, but it’s generally agreed that it all starts with the mutated huntingtin protein. What if that protein was somehow changed or blocked? This idea prompted some experimentation by Holly Kordasiewicz and her colleagues.
Have you ever sat down to write a paper at 10pm the night before it is due? It is like setting out to run a marathon. You have all your necessary snacks lined up on the desk, the perfect playlist is on, breaks are not an option, and it will probably take you around 5 hours (more or less depending how much research and dedication you prepared for this moment). Most people are more likely to encounter this type of marathon than an actual marathon; however, according to a recent research in the field of psychophysiology, marathons require just as much mental effort as the aforementioned paper.
Samuele Marcora, a professor and researcher at the University of Kent, has recently theorized that the perceived mental effort during physical activity is just as important as how strenuous as the activity actually is. Previously, the common idea has relied on the afferent feedback model – “that perception of effort results from the complex integration of sensory signals from the active muscles and other organs” and relies little on what the person actually perceives to be difficult. In the general field of exercise physiology, it has been assumed that once a subject exerts a certain amount of energy, exhaustion is reacted because there are no more stores of energy to draw upon. Marcora’s studies are beginning to prove that this previously assumed idea is not the case. Marathon runners are still able to function after a marathon, before refueling, even though they may not have been able to push any harder during the race. This is just one example of how there may be enough glycogen (units of energy) yet the runner is unable to keep pushing harder. According to these new studies, the actual energy available to a person during strenuous exercise, if there is enough glycogen present, relies on the person’s ‘brain strength’ to push past the mental boundaries caused by negative thoughts, boredom, and a build up of neurotransmitters – something that Marcora believes that runners can train to become easier.
There is a 17-year-old girl named Megan Sherow who was diagnosed with stage 3 brain cancer at the age of 13. The doctors showed no signs of optimism toward her survival, even after an aggressive treatment of chemotherapy and radiation. Megan did not want to give up on her battle to survive, and so she came across the raw food diet, which changed her life completely.
The raw food diet is based on the consumption of all raw, non-cooked, foods, mainly plants. Fruits and vegetables are the richest sources of valuable nutrients. If animal foods are eaten, they too are raw, and milk would be consumed unpasteurized. The plant-based diet mainly provides nutrient-dense foods that are rich in fiber. Fiber acts as an “intestinal broom” that picks up toxins deposited in the intestinal tract and carries them out.
The diet avoids processed foods, thus eliminating trans-fat, and providing low levels of saturated fat, sodium, and sugar. Processed foods contain chemical additives to make them look and taste better, chemical preservatives to make them last longer, and some synthetic vitamins and minerals that attempt to restore the foods’ nutritional values. Some artificial substances pass through the body, but others that do not get trapped in the kidneys, liver, intestines, and tissues like the heart, blood vessels, and brain.
Cooking foods exposes the nutrients in the food to heat, which can destroy them, especially water-soluble vitamins, antioxidants, and unsaturated fats, a popular one being omega-3s. The nutrients can be converted from an organic to an inorganic state, rendering them useless to the body. The beneficial effects of dietary fibers can also be altered and reduced. Cooking meat can lead to charring, generating heterocyclic amines, which are carcinogenic compounds. Cooking carbohydrates may produce acrylamide, which is also a potential carcinogen. Cooking has the potential destroy enzymes, lessen the nutritional value of food, and raise its acidity.
For those interested in scientific research, the Nobel Prize is an esteemed award, recognizing one’s work and dedication. However, many student researchers are often disillusioned about the kind of work that is put in to receive such high praise. More often than not, these individuals did not suddenly discover something new. To be sure, their findings are the fruits of years of research and passion in the field of science. As a great model of dedication, recent Nobel laureate Thomas Südhof provided incredible insight to our understanding of the human brain communication. But, once again, his work was in the basic-science field, on a topic which, in fact, we learn about in our introductory neuroscience courses. In this brief article, I will outline the most recent findings from Dr. Südhof’s lab in hopes of showing aspiring researchers that continued diligence and passion for learning is most important.
Neurons communicate with each other by a signaling process mediated by what is known as action potentials. Changes in concentration and electrical gradients cause the action potentials to fire down the neuron, until it reaches the synaptic bouton. It is here that one neuron forms a synapse with another neuron. The synapse is the site at which communication is happening. But, for the most part, two neurons are not physically connected, so how does communication happen? In a process called neurotransmission, when the action potential reaches the end of the neuron, an influx of Ca2+ ions cause vesicles to release certain chemicals out of the neuron, as a signal to the next. These vesicles are like little packets of neurotransmitter chemicals. Herein lies the question that Dr. Südhof sought to illuminate: mechanistically, how do these vesicles actually release the chemicals?
Stressed out? You may be at a higher risk for Alzheimer’s disease. You’re probably wondering to yourself how that is possible. Highly intelligent people who use their brains all of the time, like scientists, CEOs, and presidents, deal with stress on a day to day basis. The truth is that lack of higher education or brain activity is not the only major cause of dementia.
If keeping your brain active is a good way to prevent cognitive decline, then why did people such as Ronald Reagan and Norman Rockwell develop Alzheimer’s disease? The answer is stress. Recent studies have shown that people who deal with high levels of stress in their career or their family life are more likely to develop dementia. Stress cannot be said to directly cause dementia, but it is a trigger for the degenerative process in the brain.
An Argentine research team examined 118 patients with Alzheimer’s disease and 81 healthy individuals whose age, gender, and educational level were comparable to the Alzheimer’s patients. Both groups were questioned about the amount of stress that they had faced in the past three years. The researchers reported that 72% of the Alzheimer’s patients admitted to coping with severe emotional stress or grief, such as the death of a loved one or financial problems. This was nearly three times as many as the control group.
Have you ever wondered how long a perfect nap should be? We all decide to take naps because we feel our bodies and minds start to shut down, and the thought of doing anything productive just seems absolutely impossible. So what constitutes the perfect nap?
Your brain goes through five stages of brain activity during a sleep cycle. The first stage is falling asleep; it usually lasts five to ten minutes. This is the stage in which one may feel as though they are falling and their muscles may contract, causing what is called hypnic myoclonia. The second stage is known as light sleep. There are periods of muscle tone and muscle relaxation, along with a slowed heart rate and decreased body temperature. This is the body’s way of preparing for deep sleep. The third and fourth stages are the deep sleep stages, known as slow-wave or delta sleep. The highest arousal thresholds are seen in deep sleep, meaning that waking up is the most difficult during this stage. The final stage is called REM sleep, or rapid eye movement. The brainwaves during REM are very similar to those during wakefulness and heart rate, along with respiration, speed up. The eyes move rapidly in different directions, and intense dreaming occurs due to the heightened brain activity.
With that being said, it is now important to decide what the goal of your nap is. A nap of ten to twenty minutes yields mostly stage 2 of sleep, and therefore enhances alertness and concentration, elevates mood, and sharpens motor skills. Drinking coffee right before you take a “power nap” will aid in alertness upon waking, because it takes coffee about 20-30 minutes to fully kick in. Also try to sit slightly upright during the nap. This will help you avoid entering deep sleep and potential grogginess. It is important to note that if you find yourself dreaming during your power naps, it is a sign of sleep deprivation.