Brain Plasticity

Understanding the brain is not only intrinsically fascinating to apprehend life’s complexity or to further progress in fundamental biosciences, but it is also highly relevant to increase our well-being since the brain exhibits a power over the body that makes it capable both of triggering illness or facilitating the healing process.

Considering the dual role at play by the brain, using ascending and descending pathways to combine information issued from the external world and the internal environment, this review challenges the cerebro-centered vision of the brain. In our daily life, we construct a representation of the outside world by transforming chemical, pressure changes, and light waves into tastes, smells, touches, sounds and sights. In doing so, we create our experience of the external world by interpreting our senses through a process called exteroception. But to be compelling, this Descartes’ vision of the brain has to be completed by integration of events from inside our body. The way the brain constructs our inner sensations called interoception, is now starting to be unrevealed. As such, brain sciences have undergone, and will undergo, an important revolution, redefining its boundaries beyond the skull to prefer a more holistic vision carried out by the notion of an embodied brain acting as a coincidence detector to combine sensory experiences with corporeal homeostasis.

The goal of this review is to highlight some mechanisms by which the brain activity is controlled by internal cues for better prediction. The gut-brain axis is here taken as a canonical example to discuss about the communication between the milieu intérieur and brain functions that shapes how we feel, and how we think.

Brain-derived neurotrophic factor (BDNF) is the brain’s most-produced neurotrophin during the lifespan, essentially involved in multiple mechanisms of nervous system development and function. The production/release of BDNF requires multi-stage processing that appears to be regulated at various stages in which the presence of a polymorphism “Val66Met” can exert a critical influence.

An inaugural workshop supported by “The Leo and Anne Albert Charitable Trust,” was held October 4–7, 2019 in Scottsdale, Arizona, to focus on the effects of exercise on the brain and to discuss how physical activity may prevent or delay the onset of aging-related neurodegenerative conditions. The Scientific Program Committee (led by Dr. Jeff Burns) assembled translational, clinical, and basic scientists who research various aspects of the effects of exercise on the body and brain, with the overall goal of gaining a better understanding as to how to delay or prevent neurodegenerative diseases. In particular, research topics included the links between cardiorespiratory fitness, the cerebrovasculature, energy metabolism, peripheral organs, and cognitive function, which are all highly relevant to understanding the effects of acute and chronic exercise on the brain. The Albert Trust workshop participants addressed these and related topics, as well as how other lifestyle interventions, such as diet, affect age-related cognitive decline associated with Alzheimer’s and other neurodegenerative diseases. This report provides a synopsis of the presentations and discussions by the participants, and a delineation of the next steps towards advancing our understanding of the effects of exercise on the aging brain.

This is a summary of the 2022 Nansen Neuroscience Lectures. On 10 October 2022, Professors Henriette van Praag and David Gems gave the 2022 Nansen Neuroscience Lectures on the theme “Is ageing inevitable?” in the Norwegian Academy of Science and Letters, Oslo, Norway. While van Praag gave a lecture entitled “The benefits of exercise for brain function”, Gems gave the 2^nd lecture discussing “What causes ageing? Lessons from The Worm”. Understanding the fundamental mechanisms of ageing will pave the way to the development of future interventions to pre-empt the development of the diseases, including Alzheimer’s disease and other dementias, of later life.