Neuroscience discoveries: 2018 and 2019
There have been several discoveries throughout the years, and the definition of their impact would differ based on what one personally values. More notably, it is rather difficult and reductionistic to quantify a ‘list’ of the most seminal discoveries, implying a disregard for the rest - when in reality, science generally works by numerous minute discoveries eventually leading to a grandiose finding.
Here, I’ll provide my take on the most incredible discoveries I’ve been following in recent years.
World’s first clinical trials using Neural Stem Cells (NSCs) to treat Parkinson’s Disease
Following increasing evidence showing Neural Stem Cells (NSCs) as a potential viable cure in not only rats but also primates, the world’s first clinical induced Pluripotent Stem Cell (iPSC) transplant was held in August 2018. This was an extensive invasive surgery, involving the transplant of approximately 2.4 million dopaminergic neurons into the frontal lobe of a middle-aged man’s brain. Until now, no significant complications have occurred. It was led by the one and only Shinya Yamanaka, winner of the Nobel Prize in Physiology or Medicine in 2012 for his discovery of the indispensable iPSCs.
2. World’s first clinical Trials using NSCs for Spinal Cord injuries
I know there’s a lot of neural stem cells here, but this is truly the future - and one of the most popular areas of research today. In addition to their ability to potentially generate new organs and heal other tissues, they have been an invaluable resource for neurological studies. Moreover, they are particularly groundbreaking due to their immense healing properties - as we are viewing in today’s research.
In February 2019, Japan again has been granted permission to inject stem cells into people with spinal cord injuries to promote healing. The trials will begin later this year, and will also be the world’s first trials of injecting nearly 2 million iPSCs into the site of spinal injury. They are expected to promote healing by essentially, replacing the lost or damaged neurons and thus preserving the relevant neural connections. Again, this is after successful results in primates.
The trials will be led by Hideyuki Okano.
3. The Brain Organoid is near complete
Researchers at Case Western Reserve University (CWRU) generate oligodendrocytes, a type of glial cells important for myelin production (that provides insulation to neurons), from iPSCs into ‘spheroids’ that are resemblant of miniature ‘organoids’ - i.e, 3-D models of brain tissue, in a petri-dish (in-vitro).This is highly significant because the more accurate our models are, the more we can truly simulate and study not only the progression and markers of the disease itself, but also the effect of potential therapeutic drugs/agents on the brain tissue.
4. The entire brain of a fruit-fly is imaged
Why fruit-fly? Well, scientists need to start small, before scaling up. By studying the mechanisms of more primitive animals such as the flatworm (C. elegans) and the fruit-fly (Drosophilia melanogaster), they can apply insights to better understand human behavior at a more basic level. This will provide them the basis to investigate further complex human behaviors. It further provides insight into what differentiates humans (who apparently have ‘consciousness’) from animals.
In 2018, scientists at HHMI’s Janelia Research Campus imaged the entire brain of an adult female fruit fly (containing approximately 100,000 neurons) using serial transmission electron microscopy. Discoveries included revealing a new cell-type in the fly brain, and showcasing a full map of the fly’s synaptic circuits. This provides more insight into how the fly learns.
5. A new imaging technique can image intracellular Calcium activity
Why is this important? Essentially, when neurons fire, there is an influx of Calcium ions into the cell. Thus, being able to measure calcium transmission is an indispensable tool to understand the exact electrical activity occurring in diseased and healthy brains or brain models. Doing so will allow researchers to potentially develop electric-therapies or even devices such as the Brain Computer Interfaces (BCIs), that detect the brain’s ‘thoughts’ to operate a prosthetic arm.
Previous attempts, however, have only been able to measure such activity in only neurons within a few millimetres of brain tissue. To resolve this, in February 2019, scientists at MIT developped intracellular Calcium sensors using MRI technology and Manganese (Mn) as a contrast agent to allow cells to be viewed during imaging. Essentially, when Calcium levels are high in the cell, Manganese is present at higher level in the cells, which increases the brightness of the Calcium-rich brain regions of the MRI image. 
Moreover, this technique measures actual electrical activity within the cell. Thus, it is much more useful than the fMRI, which only indicates the amount of blood oxygen consumption in the brain. Potentially, it could be a diagnostic tool for neurons that only use Calcium (such as the heart), and to identify the role of specific neuron groups in behavior.
6. Bionic hand manages to induce proprioception
Proprioception is, essentially, the feeling of ‘knowing’ where your body parts are. Generally, amputees or injury survivors who’s lost body parts are replaced prosthetically can operate the machine, but solely relying on logic and analysis of their replaced part.
However, in 2019, École Polytechnique Fédérale Lausanne (EPFL) devised a ‘next-generation bionic hand’ that enables amputees to regain a near-natural sense of touch. It works by stimulating the nerves on the stump of the amputee, which then provides sensory feedback to the brain. This is a profound step in improving the lives of amputees.