Ever remember something and it feels like you are reliving it? That is called episodic memory, which is our ability to remember experiences.
Remembering an experience is very dependent on the timing of events. Otherwise, our memory would just be a jumble of disconnected events. A paper published in PNAS identified the "time cells" that allow us to form episodic memories.
When we experience something, the time cells in our brains put a time stamp on each memory. This allows us to recall the experience in order later.
The cells were found during an experiment with 27 people. It required placing electrodes directly in the brain.
The researchers recruited people that were about to have surgery for severe epilepsy. As part of the surgery, those people would already have electrodes placed in their brains.
The researchers displayed the words on a screen for 30 seconds. The time cells marked off segments of time about every 30 seconds as the people read through the list of words.
The time cells helped the people to remember the order in which the words appeared.
The hippocampus is involved in navigation, memory, and the perception of time. Interestingly, if a person's hippocampus is damaged, they have odd memory issues.
For example, they can have a hard time remembering the order of events they experienced. The discovery of time cells sheds light on how the hippocampus is involved in memory.
Clocks create time stamps at regular intervals of time. Time cell's time stamps are constantly speeding or slowing down. Your mood can affect the speed of time stamps.
If you are anxiously waiting for something, your time cells can make time seem much longer. But, if you are having fun, time seems faster. So, now we have scientific support for the old adage "time flies when you are having fun"!
h/t: NPR
