The results are unique, since the new data can be used for conducting non-invasive diagnostics of this important brain function, which usually suffers when subjected to various neuropsychic diseases and epilepsy. The findings were published in the prestigious scientific journal Nature Scientific Reports.
Magnetoencephalography (MEG) is a unique innovative technology for mapping brain activity with high temporal and spatial resolution.
It is used for non-evasive detection of the weak magnetic field generated by neuronal current sources. This method is based on measuring the weak magnetic fields generated by the simultaneous activity of large neuron clusters with the help of superconducting sensors, so-called squids.
With the help of MEG, MSUPE researchers measured the brain's ability to control and restrict its own excitation. It is achieved with the help of special inhibitory neurons that balance out the growing excitement in the brain's neural network and participate in the process of generating high-frequency gamma activity.
During the experiment, healthy participants were subject to visual stimulation. The researchers kept increasing the velocity of the stimuli, thus increasing the intensity of sensory input while recording the brains' high-frequency gamma activity.
The experiments showed that increased intensity of sensory input first results in increased gamma response that starts to decrease upon reaching critical levels.
This non-linear relationship between the intensity of the brain's response and the intensity of sensory input indicates that inhibitory neurons can suppress growing excitation in neural networks.
"We studied the brain activity rate of a large group of healthy adults and children," said Yelena Orekhova, leading researcher at the Center for Neurocognitive Research (the MEG center). "We discovered that despite the significant changes in the frequency and intensity of gamma activity, depending on the age of the participants, the relative suppression of this activity at a high velocity of sensory input was scaled up to the same range of values throughout the entire life."
The stability of this indicator in healthy people makes it possible for researchers to use it to carry out diagnostics of excitation control in people suffering from neuropsychic diseases or epilepsy.
These results can be used to conduct non-invasive and safe diagnostics of the excitation control function in adults and children suffering from neurodevelopmental disorders, as well as objective monitoring of the effect of new psychotropic drugs.