"Object recognition memory is central to our identity and how we interact with the world. Knowing if an object is familiar or new can determine everything from survival to day-to-day functioning, and has huge implications for memory-related diseases and disorders," said senior study author, Dr. Mark Cembrowski, an associate professor of cellular and physiological sciences at the University of British Columbia, in a press release.
The new type of neuron was discovered by Adrienne Kinman, a PhD student in Dr. Cembrowski's lab. While analyzing a mouse brain sample, she noticed a small cluster of neurons with a distinct gene expression. After further analysis, Kinman and colleagues found that the neurons were also distinct from other neurons at both the cellular and functional levels as well as in neural circuitry.
To understand more about the cells, Kinman manipulated them in mice to glow when activated. Using a miniature single-photon microscope, the researchers then observed the cells as the mice interacted with their environments. The ovoids lit up when mice encountered a new object and then stopped responding as they became accustomed to it.
"What's remarkable is how vividly these cells react when exposed to something new. It's rare to witness such a clear link between cell activity and behaviour. And in mice, the cells can remember a single encounter with an object for months, which is an extraordinary level of sustained memory for these animals," said Kinman in a press release.
Dr. Cembrowski noted that the discovery of ovoid cells contradicts conventional understanding which suggests the hippocampus contains a single type of cell to control multiple aspects of memory.
"[The findings open] the door to the idea that there may be other undiscovered neuron types within the brain, each with specialized roles in learning, memory, and cognition. That creates a world of possibilities that would completely reshape how we approach and treat brain health and disease," he said.
Sources: Science Daily, Nature Communications
