Scientists have shown that the results of thinking tests in primates can be improved by optogenetic methods - by specifically activating the desired area of the brain with light.
The work was published in the journal Current Biology, and its summary is reported by NewScientist. Rhesus monkeys were trained to follow moving dots on a computer screen. The animals had to turn their eyes to the point that lit up brighter than the others.
During training, biologists observed which area of the brain is involved in the task. For this, functional MRI was used, which shows the activity of cells in various areas of the nervous tissue. When the authors established which part of the brain is responsible for learning, they injected monkeys with a virus containing the gene for a light-sensitive ion channel.
Under the influence of light, such a channel is capable of causing neuron activation. Since the virus was embedded only in those cells that were in the found area of the brain, this made it possible with the help of light to selectively activate the necessary neurons.
The researchers repeated the visual tests with monkeys. This time, before completing the task, their brains were irradiated with light (for this, a thin optical fiber was used). It turned out that such activation can improve the performance of monkeys by at least 10 percent.
In addition, according to unpublished data, the more difficult the task, the higher the percentage. Scientists have previously shown that such optogenetic techniques can be used to study memory. In a recently published work, the researchers showed that only a few neurons can be a memory activator.