Neuroscientists at the University of Texas have used mice to uncover a simple way to improve memory. It turned out that new impressions contribute to the consolidation of even unrelated memories due to the release of chemicals in the brain. Scientists published the results of the study in the journal Nature.
An area of the brain known as the blue spot (Latin locus coeruleus, LC) plays a key role in the process identified by experts. It is located in the brain stem and performs a number of functions related to physiological responses to stimulation, anxiety levels, and sleep states. LC is one of the sources of dopamine, a neurotransmitter that induces feelings of pleasure (or satisfaction), which affects the processes of motivation and learning.
Scientists have conducted experiments on 120 mice to establish a connection between the LC and the neural circuits of the hippocampus, the region of the brain responsible for the formation of long-term memory. The hippocampus is known to receive dopamine from the blue spot.
The experiment consisted of several stages. First, the scientists placed the mice in a container filled with sand (the layer thickness reached two centimeters). Several holes were dug in the sand, in one of which food was placed. It was shown that animals that were allowed to explore an unfamiliar surface 30 minutes before learning to search for food better remembered the location of food when re-tested the next day.
In a second step, the researchers established what happens in the rodent brain when performing a search task. Neuroscientists have inserted genes encoding channel rhodopsins, light-sensitive proteins, into the neurons of mice. These compounds allowed scientists to selectively activate nerve cells in the blue spot in order to figure out how it would affect memory.
It was found that artificial excitation of LC neurons allows reproducing the effect of new impressions. Cell activation also leads to increased communication between different areas of the hippocampus, which, according to scientists, allows for better memorization.
The researchers hope the research results will help develop new teaching methods in schools and universities. In addition, the discovery will help to understand the causes of memory impairment in some diseases.