The thalamus is involved in processing information from the senses
Shutterstock/SciePro
Studies in mice suggest that the thalamus, a structure at the center of the brain that relays information from the senses, may play a role in sorting memories before they are stored for long periods. increase. To date, the thalamus has been largely overlooked in amnestic research.
Priya Rajasethupathy and her colleagues at Rockefeller University in New York studied the brain activity of dozens of mice navigating a virtual maze. When the mouse’s thalamus was stimulated while learning the maze, the mice were able to recall the learned route weeks later.
Multiple regions of the mammalian brain are involved in the process of memory formation and storage. Neuroscientists have primarily focused their attention on the hippocampus, a region identified in previous studies as important for the formation of new memories, and the cortex, where long-term memories are stored. But researchers weren’t sure where memories traveled between being formed in the hippocampus and reaching the cerebral cortex.
To see how memories are being formed in real time, the researchers used a new imaging technique that allowed them to simultaneously view the electrical activity of individual neurons in the hippocampus, thalamus and cortex. They combined brain imaging with virtual reality screens, Styrofoam balls and a sugar water reward system.
By running on a spinning Styrofoam ball, the mouse can navigate a virtual maze and access three different real-world outcomes. A large amount of sugar water, a few drops of sugar water, or bad air on your face. At the end of maze training, mice had more activity in the thalamus, suggesting to the researchers that this area may play an important role in memory.
“The thalamus has been underappreciated as a cognitive structure important to memory and memory induction processes, so when I first discovered this, it was just a shock,” says Rajasethupathy. Three weeks later, he tested memory in rodents using a technique called optogenetics to stimulate or suppress thalamic function.
Mice that received a thalamic boost during a virtual reality game were able to recall otherwise forgotten memories weeks later, such as when they drank a few drops of sugar water. The thalamus-suppressed mice were able to learn and recall pathways in the short term, but failed to form long-term memory, Rajasethupathy said. “It was a very clear sign that we really needed the thalamus to integrate.”
This memory pathway may also apply to humans, as mice are used as a model organism to uncover traits often shared across mammals. “Although this study is only in mice at the moment, it is definitely interesting and will undoubtedly evoke a lot of interest. [thalamus] I investigated the relationship between memory and human beings.
topic:
