The brain is a fabulously complex organic machine with innumerable neuronal entanglements continuously traversed by electrical impulses. Scientists have long struggled to understand, test and recreate it. However, one question remains essential: how does he learn?
Researchers from the University of Montreal have looked into the faculty of acquisition that characterizes living things. Published in Nature magazine, the study focuses on pyramidal cells of the neocortex, responsible for retaining information.
What is the brain made up of?
The brain is made up of 100 billion nerve cells divided into four distinct areas: the parietal lobe, the occipital lobe, the temporal lobe and the frontal lobe. Neurons, by analogy, look like a tree, and synapses, the connections between neurons, are like leaves.
The dynamics of calcium studied
Synaptic plasticity represents a function of the nervous system essential to memorization: it is the ability to create and break neural connections. Among other things, it allows the brain to recover from certain lesions and to delay neurodegenerative diseases.
The team of researchers from Canada focused on calcium-based synaptic plasticity. Using new computer modeling, scientists can now gain a better understanding of the synaptic change caused by the pyramidal cells that make up 80 % du néocortex. The results of the experiments confronted with those acquired virtually prove it. However, these result from a single characteristic: calcium dynamism. It remains today to study the numerous elements of variation of this plasticity.
« We do not claim that the available experimental data are sufficient to fully constrain the model or validate its predictive power”say the researchers. « Further experiments would be useful to test the model’s predictions and refine its assumptions.
The brain, an eternal subject of research
The measurements were performed on slices of rodent brains in vitro. As the researchers point out, « lhas synaptic plasticity critically depends on the dynamics of neurotransmitter release and post-synaptic calcium influxa non-physiological calcium concentration could produce plastic changes that are not representative of true in vivo learning rules”.
In addition, their new modeling would allow the entire scientific community to progress efficiently on knowledge of the brain. « Plasticity model optimization is a computationally expensive procedure, beyond the capabilities of a typical workstation. However, re-optimization should not be necessary for most researchers wishing to use the plasticity model in their own studies.
The study of the brain remains a vast field of discovery, calling upon eclectic fields of research. Moreover, very recently, scientists have found a temperature much higher than expected in our organ of thought.