Baby Zebra Fish Help Explain How the Brain Forgets

Forgetting, it turns out, is just as vital as forming memories

Hiya!

You and I both know how incredibly frustrating it is when our minds go blank and we can’t remember something. Not to mention the mysteries and sadness of diseases such as Alzheimer’s, it’s no wonder forgetting is viewed as a negative brain function. Memory is a fickle thing, and for a long time, it was thought that forgetting was nothing more than a glitch in our memory system.

But now we’re learning that forgetting is actually a vital process. On Friday, I shared with you some reasons why our minds blank sometimes. But now I want to tell you what I learned about forgetting, specifically something interesting that occurs in our brain while it happens.

How Memories Are Formed

Knowing how our brain makes memories is a good starting point if we want to understand how we forget. You probably learned the gist of it in high school, but let’s refresh our minds anyway.

Most of what we know is thanks to Eric Kandel, a professor of biochemistry and biophysics at Columbia University and a Nobel Prize-winning neuroscientist. In the 1970s, Kandel discovered that chemical signals between neurons are the biological foundation of forming memories and learning.

When neighboring neurons become excited simultaneously, neurotransmitter chemicals shoot between them, connecting the neurons and forming a synapse. This process forms our memories. You may also remember that whether we retain the memory depends on how often we visit it.

These synaptic connections are short-lived for short-term memories when the information is needed for a limited time. But the more we revisit a memory or recall information, the stronger the synapses become — something that appears to be true for all animals capable of learning.

But forgetting is more than just weak synapses, as previously assumed. In fact, considering we live in a world of opposites — hot/cold, up/down, love/hate — perhaps it was a bit naive to think that forgetting is a flaw. I mean, if all animal brains possess neurotransmitters to create these connections to form memories, then it makes sense the brain also has a way to sever them.