Researchers at Penn State conducted experiments with mice to investigate the link between the circadian system and memory formation. They identified a gene called Period 1, known for its involvement in the body’s circadian clock, which also plays a crucial role in improving daytime memory performance. The study used an object memory location task to test the mice’s memory and found that memory consolidation, the phase where molecular changes occur in the brain to store memories, was influenced by the time of day.
The researchers sequenced the genes expressed in the dorsal hippocampus of mice trained in the memory task during the day and at night. They discovered that the gene activity in mice trained during the day significantly increased, while fewer genes changed their expression in the mice trained at night. The gene Period 1 was expressed at higher levels during the day and reduced at night, suggesting that it has a separate function in regulating memory consolidation across the day/night cycle.
By inhibiting the activity of Period 1 in the dorsal hippocampus, the researchers observed impaired memory in mice, highlighting the gene’s importance in memory formation. This study enhances our understanding of how memories are formed at the molecular level and may lead to insights into memory-related dysfunctions and potential therapeutic approaches. Furthermore, the link between the circadian clock and memory formation could provide valuable knowledge on optimizing learning processes in humans.
Source: Pennsylvania State University