Science Alert reports:

When it comes to how we experience, interact with, and navigate our world, timing is everything. And new research in mice suggests a specific set of cells is fundamental to the way we learn complex behaviors that rely on timing.

The discovery by a team at the University of Utah in the US could eventually help detect onset of neurodegenerative diseases that affect time perception, like Alzheimer’s.

To create a memory for your own personal archives, your brain must encode the timing and sequence of events as you’re experiencing them. It creates this timeline using circuits in the medial temporal lobe (MTL), one of which is the medial entorhinal cortex (MEC).

This MEC circuit has ‘time cells’ that fire at specific moments during tasks, on a scale of seconds and minutes, a kind of organic internal metronome that helps us keep track of time in the moment.

Scientists suspect this ‘timer’ may leave its mark on episodic memories, so the ‘frames’ of our experience are replayed in sequence, with a built-in rhythm. But to do so, these time cells would need learning dynamics that allow them to encode different temporal contexts.

We know ‘spatial cells’ within the MTL can reorganize their ‘firing fields’ according to spatial contexts, as an animal moves through different and changing environments.

The researchers wanted to investigate whether time cells have a similar ability to ‘re-map’ to different temporal contexts. They combined a complex time-based learning task with brain imaging to watch patterns of time cell activity. [Continue reading…]