The Neuroscience of Stickiness

Have you ever wondered why you can remember the chorus of every pop song from your tweens? But, now that you’re giving the most important presentation of your life, you’re drawing a blank?

You’re not alone.

ProTip: Still can’t remember the next point you were supposed to make? Stall for time by moonwalking, a crowd pleaser at any event.

This is just one reason why the Lundbeck Foundation offers research grants for researchers in the biomedical and natural sciences, including the European Brain Research Prize. Since 2011, the “Brain Prize” has awarded €1 million to scientists trying to solve such perplexing cognitive puzzles. Which is great news for you and me.

This year’s prize went to memory researchers and neuroscientists Graham Collingridge, Richard Morris, and Timothy Bliss, who have decoded the mechanism for Long Term Potentiation (LTP).

In lay terms, they may have figured out why repetition and other specific stimuli strengthen memory. It’s a mechanism that could help scientists make information easier to remember, bad memories disappear forever, replace Adderall with vitamins, lead to a cure for Alzheimer’s, or help you deliver more memorable presentations.

What Is Long Term Potentiation?

To oversimplify, LTP is the process of filing something away in your long-term memory.

Your brain can store memories for a lifetime, or just 30 seconds. If you only need to remember a plot point for the duration of a commercial break, your brain usually keeps that memory on file for a just few minutes. Tomorrow, you probably won’t remember that particular joke or cliffhanger at all.

Unless you really want to do so—consciously or subconsciously.

You store memories for longer periods by increasing your LTP. You probably already know a few cheats.

For example, if you want to remember someone’s name, repeat it several times during your first conversation. (e.g., “So, Jane, how does your job contribute to the organization? That’s very interesting, Jane.”) Or, link it to another memory: “She looks like Jane from Disney’s Tarzan movies.”

But, why do those strategies work?

It all comes down to a series of neurochemical reactions in your hippocampus. These involve calcium, magnesium, and low-frequency action potentials that release glutamate… we’ll let this eight-minute video explain the science behind it.

It all makes sense now, right?

When you stimulate different pathways surrounding the same memory—through repetition, studying, storytelling, association with other memories, or learning something through multiple sensory pathways (say, visually and aurally, like during a PowerPoint presentation)—you are actually constructing a cellular pathway. Each long-term memory physically changes your brain.

Deep inside your hippocampus, each of these activities is stimulating an electronic pathway using simple chemical reactions—firing the neurons—that repeatedly engage the same synapses, or groups of synapses. This strengthens the connection, and keeps it open for indefinite retrieval.

For example, let’s say you learn something in a class. Your professor explains photosynthesis, and draws a diagram on the chalkboard. This sends two different surges of electricity through the same group of synapses, opening and strengthening them. This probably isn’t the first time you’ve heard of photosynthesis, either. So memorization will be even easier, as that cluster of synapses already exists.

Taking notes during the lecture fires those same synapses yet again. If a classmate asks a question, another round goes off. Your brain chemistry and structure is actually changing on a cellular level, as you build a bundle of photosynthesis-related synapses that will now endure for weeks, months, or even years.

If you study your notes later, and perhaps read the associated chapter in your textbook, it becomes even stronger. Have a nap or a great night’s sleep immediately after studying, and your dreams fire those synapses a few more times. This is Long Term Potentiation.

the neuroscience of stickiness plant growing in the window

So… I’m supposed to put plants near windows, right? I think there was something about watering, too.

Does it work? Fast forward a few decades, after you haven’t thought about photosynthesis in years; perhaps when you’re reading a blog to improve your public speaking skills. Do words like “chlorophyll” or “ATP” come bubbling up out of nowhere, unused since your university biology class?

If so, at some point you successfully used LTP to create a long-term memory, a process called “consolidation.”

You can reverse it, too. Another process, called Long Term Depression, actually tears down long-term memories. No one is sure how or why the brain does this, though it may be to make room for new knowledge, a means for old dogs to learn new tricks.

For example, if you’re of a certain age, you probably used to memorize dozens of phone numbers almost immediately. When a friend changed phones, you almost immediately forgot that number, although it had been easily accessible in your long-term memory for years. Today, you may have forgotten how to memorize phone numbers at all. There’s no need to waste valuable real estate in your brain on such things.

This is called “synaptic plasticity.” Your brain changes—growing, shrinking, becoming smarter, displaying signs of dementia—throughout your life. Despite what you may have been led to believe, not even your IQ is static. It goes up and down depending on how, and how much, you use your brain.

Your brain remains plastic until the day you die, and LTP may well prove one of the most important processes in maintaining healthy plasticity.

Neurons That Fire Together, Wire Together

“Understanding memory is one of the grand challenges of neuroscience,” explains one of the Brain Prize winners, Richard Morris, Professor of Neuroscience at the University of Edinburgh. “I think we all recognize that memory is absolutely fundamental to so many aspects of our daily life [which is why] disorders of memory are greatly feared.”

When you learn those “cheats” to improve your memory—repetition, rhyming, storytelling, and the like—you aren’t thinking about the chemicals involved in the LTP process.

But, according to Morris and his fellow Brain Prize recipients, you need a variety of chemical—calcium, magnesium, and a protein called PSD-95—to fire that synapse, strengthen that memory, and remember the name of your boss’s husband. All the naps and repetition in the world can’t help a mutant mouse, bred to be unable to produce PSD-95, remember how to run a maze. Add that protein, and its memory operates normally.

Your memory may one day be just as easily manipulated.

There are already several working hypotheses built on this research. For example, if you block the formation of something called “dendritic spines,” structures that physically grow and retract in the hypothalamus during the formation of new memories, you might be able to block a memory from being formed. Or, if you increase a specific type of calcium activity in the postsynaptic cell before the memory is formed, which helps prepare synapses for stimulation, you might make memorization easier.

We’re looking forward to finding out why these people file every detail of their daily lives in their long-term memory, and making sure our partners and coworkers never figure out how to develop that ability.

The research may also explain why you have difficulty recalling memories made before you were three or four years old. An LTP protein called the “NMDA receptor,” which forms tiny structures in the hippocampus, has also been detected on the cerebral cortex, cerebellum, amygdala and other excitatory synapses. This suggests that sites of memory are stored in several locations when you are young, but those formed outside the hippocampus are eventually wiped out, or relegated to the subconscious.

For the purposes of your upcoming speech or presentation, however, you just need to remember the LTP soundbite, “Neurons that fire together, wire together.” You want to write your speech around a few central ideas, and then reinforce those ideas—those clusters of memory synapses—before, during, and after the presentation. What we at Chainsaw Communications have been advising all along.

And, next time you’re preparing for your next public speaking gig, think about those pop songs you still remember from your tweens. The repetition, the cheerful melodies, the videos, the sing-alongs, and all the great memories you associate with them. That’s why you remember every word, but not the next portion of your presentation. If you get those target clusters of synapses firing, however, and you’ll be back on track.

2016-10-21T11:03:07-05:00 By |Categories: Neuroscience, Presentations, Psychology|Tags: , , |