The imagination has an amazing ability to compress time.
In a few seconds our brains can play out events that would take hours or days at real time.
It’s an ability we take for granted and one we need to help plan for the future.
The key to how we are able to do this is a type of brain wave which is separate to the one we use for remembering real-time experiences.
Brain cells use a series of different electrical frequencies to communicate with each other.
It’s like the way radio waves are used to communicate over long distances.
One of these frequencies, however, allows the brain to play back memories or plan future events in fast forward.
Dr Laura Colgin, one of the study’s authors, explained:
“The reason we’re excited about it is that we think this mechanism can help explain how you can imagine a sequence of events you’re about to do in a time-compressed manner.
You can plan out those events and think about the sequences of actions you’ll do.
And all of that happens on a faster time scale when you’re imagining it than when you actually go and do those things.”
It’s known that fast gamma rhythms are used to encode memories happening right now, in real time.
The researchers discovered that slow gamma rhythms are used to retrieve memories and plan for the future in fast forward.
Naturally, the extra speed causes the memories and plans to lose resolution.
It’s the same as when you compress a file on the computer and it loses some information along the way.
The findings could also have implications for mental illness, Dr Colgin thinks:
“Maybe they are transmitting their own imagined thoughts on the wrong frequency, the one usually reserved for things that are really happening.
That could have terrible consequences.”
The study was published in the journal Neuron (Zheng et al., 2016).
Brain image from Shutterstock