Though PLP is obviously prevalent among amputee patients, there is not a single drug prescribed to address phantom limb pain specifically. Many doctors will prescribe antidepressants, anticonvulsants, or narcotics, which may help, but do not help the majority of patients suffering from PLP.  Alternative treatments such as acupuncture may be recommended, but the possibility of these treatments actually curing PLP symptoms is very low. Ultimately, lack of knowledge concerning phantom limb is a barrier to effective treatment.

However, PLP has been gaining more visibility and has been largely addressed in popular television shows such as Grey’s Anatomy because of the perplexity accompanying it. By appearing in TV shows, PLP gains exposure. While it is a very interesting phenomenon in the medical community, the pain experienced by patients is serious and necessitates more research into treatments. Visibility in popular media can inspire an increase in research, possibly spiking the interest of scientists in this field. In addition, television coverage helps PLP patients feel like their pain is being taken seriously and gives them courage to speak about their pain without fear of being judged.

There are many hypotheses about how PLP works, and what constitutes PLP. However, none of these theories have been proven or widely agreed upon to date. One possible explanation is that the pain results from the brain working to rewire its system in order to make up for the deficit of neurons and axons which were lost with the amputation. For some people, PLP goes away with time,but recovery from and duration of PLP varies case by case.

Recently, at École Polytechnique Fédérale de Lausanne (EPFL), scientists found a way to map the neural connections for the artificial limbs of patients, using ultra-high field functional magnetic resonance imaging (fMRI). fMRI examines blood flow in the brain to detect areas of activity. This is used by doctors and scientists to diagnose diseases in the brain, and possibly to map out all of our neural connections. fMRI can be useful in analyzing what we’re thinking and feeling. It is believed that a typical MRI scanner has a strength equal to that of three teslas, a force about 50,000 times stronger than the Earth’s magnetic field. fMRI employs ultra-powerful magnets that are five times stronger than the magnets inside of a regular MRI scanner.

Scientists from EPFL have also found a way to show how the brain re-maps sensory and motor pathways. This technology uses robotic artificial limbs controlled by the brain with the help of targeted motor and sensory reinnervation (TMSR) using normal MRI scanners. TMSR is a surgical procedure that reroutes residual limb nerves towards remaining muscles and skin, enabling amputees to control robotic prosthetic limbs.

These findings put science a step forward in understanding what happens in the brain once a person loses a limb. They also give rise to new and better inventions, making it easier for amputee patients to live close-to-phantom-pain-free lives. Mapping neural connections is a huge step on the path towards a better life for many.

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How optogenetics works is quite unique. First, the desired neurons for research are genetically modified to express a light sensitive protein, opsin, which can take the form of an ion channel, for example. Optogenetics works with Channelrhodopsins (ChRs), which are light-gated ion channels. Light-gated ion channels like ChRs are activated only when struck by a specific frequency of light. When the correct frequency is used to illuminate these neurons, it leads to an ion channel opening. When these channels are open, it allows the passage of positively-charged ions, which causes depolarisation, also known as an action potential. The ability to control specific neurons by manipulating their activation and deactivation using light has led scientists to better understand mood disorders, addiction, and even Parkinson’s disease. The key to understanding why and how such disorders and diseases occur: to first find the path in which it takes place, and then figure out what exactly goes wrong in that path.

The proton ‘starter’ that was recently discovered is known as nanohalosarchaeon Nanosalina (NsXeR), and it belongs to the class of proteins called xenorhodopsins. Xenorhodopsins functions have been better understood because of the discovery of NsXeR.

NsXeR is a powerful pump that’s been shown to induce action potentials in hippocampal neuronal cells to the perfect frequency which opens those frequency gated channels in rat brains. They’ve been characterized as inward opening pumps that are an alternative to the ChRs that have been used in research until now. NsXeR is very selective and only pumps protons into the cell, regardless of the cells concentration. Due to its selectivity and unique features, it is considered to be much more advantageous than ChRs. For instance, NsXeRs selectivity makes it safer to use during research, because unlike ChRs, only one specific positive ion is being transported, lowering the risk of possible cellular side effects during research trials.  

Optogenetic techniques have only ever been used in one clinical trial in 2016. A blind Texan woman underwent the first human clinical trial using optogenetic techniques. This has been the only human trial done so far because the methods are quite invasive. First, the brain needs to be genetically altered, and then a light delivering device must be implanted into the brain. However, research in the field is rapid, and hopes of continuing human clinical trials are high. The discovery of NsXeR brings researchers closer to the possibility, which in turn brings them closer to advancements in treatments for various diseases and disorders researched in the field of neuroscience. This field of research may be the key we’ve been waiting for to unlock the answers to treatments for millions of people around the world.

The paper on the finding of the NsXeR protein was published in Science Advances by an international team of researchers from Moscow Institute of Physics and Technology, Forschungszentrum Jülich, and Institut de Biologie Structurale. Vitaly Shevchenko, the lead author of the paper and a staff member at the MIPT Laboratory for Advanced Studies of Membrane Proteins stated, “So far we have all the necessary data on how the protein functions. This will become the basis of our further research aimed at optimizing and adjusting the protein parameters to the needs of optogenetics.”

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Over the past ten years, the public has become increasingly aware of mental illnesses and its impact on people’s lives. Scientific research has brought a new understanding of disorders that were a mystery to many. Mental disorders are very real and their effects on one’s life are tremendous. Although the punch cannot be seen, the impact is there.

One type of mental illness is schizophrenia, a biochemical brain disorder that confuses a person’s reality with a fake one. The manifestation of schizophrenia can greatly differ among individuals: some will only experience one episode in their life, while others will experience many more. There are also different kinds of schizophrenia ranging from acute to chronic. Auditory hallucinations are one symptom that affect more than 70 per cent of people with schizophrenia. Other symptoms include delusions, disturbed thinking, and social withdrawal. There is no definite cure that will work for every patient because of the lack of knowledge concerning this disorder.

Schizophrenia affects men and women of various ages. A specific gender or age is not affected more than others. In the United States, there are around 3.5 million people who suffer from schizophrenia, and around 20, 000 of whom are homeless, and don’t have access to medical aid.

People with schizophrenia require lifelong treatments with a choice of various antipsychotics, counseling, or support groups and homes. All antipsychotics available come with a long list of side effects, making patients reluctant to take them. Schizophrenia was discovered in the late 1800s, but was not named until 1910, and was not taken seriously until quite some time following that. Only recently has research for different treatments of schizophrenia started. Recently, a French research group presented a new finding on schizophrenia to the European College of Neuropsychopharmacology (ECNP) Congress. Not only did they find the exact brain area responsible for auditory hallucination in schizophrenic patients, they also figured out how to improve this condition in most patients.

Sonja Dollfus, a professor of the University of Caen, and her colleagues made their discovery by bringing a previously proven method into their hypothesis for schizophrenia treatment.Ttranscranial magnetic stimulation (TMS) has been thought of before as a treatment for psychiatric conditions and has been successful in other cases. However,  a lack of controlled trials of TMS were applied to a part of the brain to aid in Schizophrenic hallucinations. Dollfus and others used this to create their hypothesis that applying TMS to the temporal lobe would trigger hallucinations and would improve a patient’s conditions. In their clinical trial, 26 patients received TMS treatment while 33 received a placebo treatment. Two weeks after the trial, the patients of both the control and placebo group were examined. The research group found that 34.6 per cent of the control group showed a significant response whereas only 9.1 per cent of the placebo group responded. According to ECNP, a significant response is anything above 30 per cent, making this finding even more impressive.

At the ECNP Congress, Dollfus stated, “It seems that we now can say with some certainty that we have found a specific anatomical area of the brain associated with auditory verbal hallucinations in schizophrenia . . . we have shown that treatment with high frequency TMS makes a difference to at least some sufferers, although there is a long way to go before we will know if TMS is the best route to treat these patients in the long-term.”

What does this mean for future treatments? The key for researchers is to fully understand what the brain disorder entails. Something of this significance will have a great impact on the types of research that will follow and influence their hypotheses. Knowing the specific part of the brain that’s associated with hallucinations can bring researchers closer to understanding and developing precise treatments for hallucinations, and perhaps also other symptoms affecting millions of schizophrenic patients today.

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