Neuroscientists at the Autonomous University of Madrid (UAM) have managed to measure for the first time the fundamental structural parameters of existing synapses between the axons of neurons in the thalamus and the cerebral cortex, the three-dimensional structure of intercellular contacts that allow information from the senses flow into the cerebral cortex. The study is published in the journal Cerebral Cortex and is attached to The Human Brain Project by the European Union.
This is a significant development, both technical and conceptual, to understand how the ‘cellular hardware’ helps create a hierarchical order in the flow of information through neural networks of the brain.
“We have discovered structural specializations that could explain why these synapses in particular have such a functional power which, despite their relative small numbers, impose their rhythm of electrical activity and responsive fields to the cerebral cortex’s neurons, to which they innervate; making, for example, that a specific region of the cerebral cortex selectively engages in processing tactile, or visual information, etc.” said Francisco Clascá, director of the study.
“The parameters that have been measured are also valuable data for developing advanced computational models on the functioning of brain circuitry,” Clascá added.
During the three years in which the work was conducted, the researchers used techniques of selective long-distance marking of axons in the brain of mice. This method was combined with advanced techniques of three-dimensional electron microscopy to accurately measure and display tiny subcellular structures.
The study involved the collaboration of researchers from the Institute of Neuroscience and Medicine at Forschungszentrum Julich (in Germany) and the Laboratory of Cortical Circuits of the Polytechnic University of Madrid.
Source: SINC
