Mind

How Was My Childhood? I Forget.

Researchers may have found the cause of infantile amnesia.

By Lisa RaffenspergerNov 26, 2014 12:00 AM
Huan Tran/Ikon Images/Corbis

Newsletter

Sign up for our email newsletter for the latest science news
 

What’s your earliest memory? Most people can’t remember events before about age 3, a phenomenon called infantile amnesia. In May, researchers announced they finally might have pinpointed the cause.

As neurons form rapidly during infancy and early childhood — through a process called neurogenesis — new neurons rearrange connections and destabilize existing memories. Mice, like humans, display infantile amnesia. To explore why, researchers trained mice to fear a particular environment, then gave some mice access to running wheels, since exercise is known to stimulate neurogenesis. Afterward, researchers found, the exercisers had largely forgotten their fear, whereas the sedentary mice still remembered it.

The researchers then examined the opposite effect: slowing neurogenesis in infant mice by giving them a drug. They found that mice whose neuron growth was stunted were much more likely to remember their earlier fear a week later.

All this hints that a similar mechanism may be at work in humans’ early childhood.

The group plans to study the utility of forgetfulness next. Normally people think forgetting something is bad, but certain types of forgetting can be helpful, study author Paul Frankland says: “It works better to forget lots of details. You don’t want your mind cluttered up with that stuff.”

So don’t fret your forgotten youth. You may have it to thank for lots of memories gained since then.

1 free article left
Want More? Get unlimited access for as low as $1.99/month
Already a subscriber? Log In or Register
1 free articleSubscribe
Want unlimited access?

Subscribe today and save 70%

Subscribe

Already a subscriber? Log In or Register
More From Discover
Recommendations From Our Store
Shop Now
Stay Curious
Join
Our List

Sign up for our weekly science updates.

 
Subscribe
To The Magazine

Save up to 70% off the cover price when you subscribe to Discover magazine.

Copyright © 2021 Kalmbach Media Co.