It is likely that the region of the brain responsible for the formation of memory also affects the motivation of mammals.
The hippocampus is the part of the brain involved in memory consolidation. It helps translate short-term memory into long-term memory, but biologists at the University of Toronto have shown that it plays a role in decision-making as well.
To do this, they conducted a series of experiments on mice, examining the ventral hippocampus - that part of the brain of rodents that correlates with the anterior hippocampus in humans. There are two departments in this area, labeled CA1 and CA3. According to psychology professor Rutsuko Ito, the traditional approach is that these divisions are associated with the dentate gyrus and perform the same function. Information passes through the dentate gyrus and enters first into CA3 and then into CA1. Since all parts of the chain are in the same system, it was previously assumed that they perform the same function, but this hypothesis turned out to be erroneous.
Scientists conducted an experiment with the so-called "striving-avoidance" conflict, which was described by psychologist Kurt Lewin in his book "The Psychological Situation of Reward and Punishment." Its essence is the simultaneous desire of the individual to make a certain decision and abandon it, since it brings positive and negative results. In the labyrinth, mice were asked to choose: a neutral passage or one that both brings reward and unpleasant consequences.
Labyrinth Variants / Current Biology
The researchers found that when CA1 was deactivated, mice were more likely to avoid conflict, and when CA3 was deactivated, on the contrary, they were more willing to take risks. After the experiment, Rutsuko Ito commented on the results:
“It seems that CA1 and CA3 have opposite functions in the ventral hippocampus. This is a strange bi-directional and oppositional effect, and it contradicts everything we thought before."
According to her, this mechanism probably plays an important role in motivational behavior and changes with mental deviations. For example, depression can be accompanied by the "shutdown" of CA1, and drug addiction, on the contrary, CA3.
Last month, scientists at the University of Southern California unveiled an invention that helped patients with neurodegenerative diseases improve their episodic memory by 37 percent.