Scientists from the National University of Singapore (NUS Medicine) have uncovered a previously unknown role of the hippocampus in memory formation, revealing how social interactions enhance the brain’s ability to convert fleeting experiences into lasting memories.
The study, published in the journal PNAS, demonstrates that the hippocampus, which is recognized as the brain’s main memory center, is critical for the formation of long-term memory. Within this structure lies the lesser-studied sub-region, CA2.
The research by NUS Medicine scientists established that CA2 is activated during social interactions, and it is this action that strengthens the long-term memory retention process.
The laboratory study showed that when scientists temporarily deactivated the CA2 region using a special method (chemogenetics), social interactions lost their ability to enhance memory. This finding confirmed the pivotal role of CA2.
Further analysis revealed that CA2 neurons form long-term memories by collaborating with the CA1 region. They utilize a process called metaplasticity—which ensures the strengthening of memory proteins present in the brain.
The researchers emphasize that social interaction is a biological necessity, and not just a pleasant activity. It directly alters the way the brain works.
The results obtained explain why loneliness and prolonged social isolation are closely linked to memory decline and conditions such as dementia. The study also clarifies why social and memory impairments often coexist in psychiatric disorders.
According to NUS Medicine scientists, strengthening the connections from CA2 to CA1 could become a new strategy for “rescuing” memory function in vulnerable groups (such as the elderly) and in the fight against dementia.
Potential future interventions may include specialized medications, brain stimulation methods, or lifestyle-based therapies.
