Local activation of CA1 pyramidal cells induces theta-phase precession. (https://pubmed.ncbi.nlm.nih.gov/38301006/)

These scientists wanted to understand how a specific part of the brain called the hippocampus generates a special pattern of electrical activity called theta-phase precession. They were trying to figure out where this pattern comes from and how it works.

To do this, the scientists used a special technique called optogenetics, which involves using light to control the activity of specific cells in the brain. They focused on a part of the hippocampus called CA1 and implanted tiny devices in the brains of mice to control the activity of certain cells in that area.

Then, they made the mice run on a straight track while shining light on the cells in CA1. This caused the cells to create artificial "place fields" in the mice's brains, which are like imaginary maps of the track. They found that more than one-third of these artificial place fields showed a specific pattern of activity called synthetic precession.

Interestingly, when they did the same experiment in another part of the brain called the parietal cortex, they didn't observe this synthetic precession pattern. This means that the precession pattern is specific to the CA1 region of the hippocampus.

These findings suggest that there is a special mechanism or generator within the CA1 region of the hippocampus that produces this precession pattern. The scientists ruled out several possible explanations for how this pattern is generated and concluded that it must be something unique to the CA1 region.

By understanding how the brain generates these patterns of activity, scientists can learn more about how the brain works and how it helps us remember and navigate our surroundings.

Sloin HE., Spivak L., Levi A., Gattegno R., Someck S., Stark E. Local activation of CA1 pyramidal cells induces theta-phase precession. Science. 2024 Feb 2;383(6682):551-558. doi: 10.1126/science.adk2456. Epub 2024 Feb 1.