Neuroscience & Neurology 1 Comment Best and Worst of Neuroscience and Neurology – November 2015

[To be used as an example - from BrainBlogger.com]

Maybe this is just a reflection of the annual funding cycle, but it is common to see a lot of high quality publications towards the end of year. And as the end of 2015 is approaching, choosing the most interesting articles for this review becomes a more challenging task. Here, I’m presenting only few of the studies that are worth talking about. As usual, the choice of article for inclusion mostly reflects my personal opinion about their significance.

This month, scientific community marked the birthdays of two scientists: Charles Scott Sherrington and Edgar Adrian. Both Englishmen are best known for their shared Nobel Prize in Physiology received in 1932. Their research established the function of neurons in sending the messages within the neural system and demonstrated the basic rules governing this phenomenon. The works of Adrian and Sherrington laid foundation of modern experimental neuroscience.

THE BEST

Fitness level correlates with strength of brain connections in elderly

Resting-state functional connectivity in the brain is a measure of brain health, and it tends to deteriorate with age. A new study demonstrates that brain connectivity in older adults correlates well with the level of cardiovascular fitness.

The measure, however, is not dependent on the level of person’s physical activity: this means that even those who are not particularly active physically but managed to remain fit in old age still rate better in the brain health measurements. The findings help to understand how fitness protects against age-related neurodegeneration and dementia.

Sensors for proprioception found

It is often said that people have five senses, but this is not really correct. At least one obvious sense which is not on the classical list is proprioception: this sense tells us where our body parts are relative to each other and space around us. Obviously, this sense is important for our balance and body movements.

Finding the neural circuits related to the sense of proprioception has turned out to be a difficult task, however. An article published this month identifies Piezo2 as a sensor protein that translates stretching of muscles and tendons into the proprioceptive signal. Interestingly, the same protein mediates the sense of touch.

Human brain more responsive to environmental influences compared to other primates

The term plasticity refers to the propensity of brain to be altered by its environment. New research shows that compared to chimpanzees, our closest evolutionary relative, the human brain is shaped to a much larger degree by social and cultural influences and other adaptations to the changing environment. The brain organization of chimpanzee, on the other hand, is highly heritable (i.e. genetically determined) and shows little variability.

It is quite likely that high brain plasticity was one of the major evolutionary advantages of human species allowing successful adaptation to a vast range of environments.

Where happiness happens?

Happiness is rather elusive thing. Even defining it in scientific terms is far from straightforward: different people feel happy for different reasons.

Japanese scientists used MRI scans to try and locate happiness within the brain structure. It turned out that people who score higher on happiness ratings have a larger mass of grey matter in their precuneus. The precuneus is a part of superior parietal lobule between the cerebral hemispheres. Interestingly, some research demonstrates that meditation causes increase of grey matter in this region.

New concussion biomarker predicts cognitive impairment

Although most concussions get resolved relatively quickly, approximately one in five patients suffers cognitive impairments that last for several months or even longer. It is now believed that diffuse axonal injury associated with concussion may cause degradation of more damaged axons. The degradation process causes formation of some byproducts, including protein SNTF.

Researchers demonstrated that the level of SNTF is higher in people who suffer from greater cognitive dysfunction. Thus, SNTF level can be used as a marker of axonal injury and indicator of potential cognitive impairment in patients.

THE WORST

The worst doesn’t really mean the results are that bad – this is more a reflection of getting some data that do not meet expectations or defy the currently hold views. Very useful lessons can be learned from such findings.

Working memory: not as simple as it looks

Working memory is called upon when a piece of information needs to be kept in mind for a short period of time. It was always assumed that underlying process should be rather simple.

Measuring the brain activity during various memorizing tasks revealed that it involves rhythmic activity of hippocampus which alternates between less excited and more excited states twice per second. The absence of this rhythmic pattern was associated with mistakes in memorizing. Even though the processes behind the pattern are not clear, it is obvious that formation of working memory involves rather complex processes.