Summary: A new investigation shows that the cortex of the brain can reorganize quickly after losing neurons, allowing other nerve cells to take over the lost functions. The scientists studied neuronal networks in the auditory cortex and discovered that although the sound processing patterns were briefly interrupted, the brain formed almost identical patterns in a matter of days.
Neurons previously not participated in processing stimuli intervened to compensate for loss. This adaptive mechanism could help explain how the brain maintains the function during aging or in diseases such as Alzheimer and Parkinson.
Key facts:
Fast reorganization: neural networks restore activity patterns only days after the loss of neurons. Functional compensation: Unused neurons can adapt to assume the roles of lost cells. Clinical involvement: Cerebral resilience can explain in aging and neurodegenerative conditions.
Source: Johannes Gutenberg University Mainz
How the brain greatly maintains its function when neurons are lost, this is what researchers at the Mainz University Medical Center, the Frankfurt Advanced Studies Institute (Fias) and the Hebrew University (Jerusalem) have deciphered.
They show that neuronal networks in the cerebral cortex are reorganized in a short period of time, with other nerve cells that take care of the tasks of lost neurons.
These findings could form the basis for future research on natural aging processes and neurodegenerative diseases such as Alzheimer’s or Parkinson.
The study is published in the journal Nature Neuroscience.
Nervous cells (neurons) are the most important construction blocks of the brain.
They form the basis for all mental and physical functions, such as thought, feeling, movement and perception. In the course of life, nerve cells in the brain can be lost for several reasons: they die due to age -related processes, they are damaged by toxins such as alcohol or neurodegenerative diseases such as Alzheimer’s and Parkinson’s and those of Parkinson’s lead to a faster progressive loss of neurons.
While most body organs regularly replace old or damaged cells to maintain their organ function, new neurons are only formed in certain regions of the brain. In the cerebral cortex, which is responsible for complex thought processes and perception, the ability to form new neurons is very limited in adulthood.
“However, clinical studies have shown that the function of the cortical brain is often surprisingly resistant to the loss of neurons that occurs in the course of aging or neurodegenerative diseases,” explains Simon Rumpel, head of the Systems Neurophysiology Research Group at the Institute of Physiology of the Medical Center of the University of Mainz.
Until now, it was not known how the brain can compensate for the loss of nerve cells and maintain its function. To discover this, the research team used an animal model to investigate neural networks in the auditory cortex, which is responsible for the processing of acoustic stimuli.
The perception of sounds is based on activity patterns that are triggered in the brain by acoustic stimuli. These patterns are very complex. PhD. The student Bastian Eppler and the senior fellow Matthias Kaschube in FIA contributed significantly to the analysis of this data and the interpretation of the results with their experience.
The researchers found that activity patterns are initially destabilized when the loss of a few specific nerve cells is deliberately induced. This indicates that the neuronal network responsible for the perception of sound is in a delicate balance.
After just a few days, very similar activity patterns are formed again. The nerve cells that were not previously activated by acoustic stimuli now acquire the ability to take the place of lost neurons.
“We assume that this newly discovered neuronal mechanism plays an important role in the loss of nerve cells in natural aging processes, as well as neurodegenerative diseases,” says Rumpel. Future research efforts could aim to support this neuronal reorganization.
On this neuroscience research news
Author: Simon Rumpel
Source: Johannes Gutenberg University Mainz
Contact: Simon Rumpel – Johannes Gutenberg University Mainz
Image: The image is accredited to Neuroscience News
Original research: open access.
“Homeostasis of a representation map in the neocortex” by Simon Rumpel et al. Nature neuroscience
Abstract
Homeostasis of a representation map in neocortex
The cortical function, including sensory processing, is surprisingly resistant to the loss of neurons during aging and neurodegeneration.
In this article, we use the auditory mouse cortex to investigate how homeostatic mechanisms protect the representative map of the sounds after the loss of neurons.
We combine calcium images of two photons with a directed micro -labing of 30–40 sound -sensitive neurons in layer 2/3.
The microablation led to a temporary disturbance of the representation map, but recovered in the following days.
The recovery was mainly driven by neurons that initially did not respond to the sounds, but obtained response capacity and strengthened the network correlation structure.
On the contrary, the selective microablation of inhibitory neurons caused a prolonged alteration, characterized by destabilized sound responses.
Our results link the tuning of individual neurons and plasticity with the stability of the representation map at the population level, highlighting the homeostatic mechanisms that safeguard sensory processing in neocortex.
