S2E4. Memory Is Overrated

Lisa Genova is a neuroscientist and author. If you’ve heard of her, it’s probably because she wrote the book “Still Alice” which was made into a movie starring Julianne Moore (who won the Best Actress Oscar for her portrayal) and Alec Baldwin. It was the story of a linguistics professor who develops early onset Alzheimer’s.

Now she’s written another book titled: “Remember: The Science of Memory and the Art of Forgetting.” I read it last week and I recommend it to you. It’s an extremely helpful guide to understanding what memory is and what it is not. This, in turn, provides insight into what changes in memory are normal—and which are not—as we age.

She writes in a breezy, conversational style and makes even difficult topics readily digestible, resorting to jargon only when absolutely necessary. Here are some take-aways:

For starters, we don’t remember everything. We just remember important things. That’s why you probably don’t remember what you had for dinner a week ago Tuesday (unless it was your birthday or anniversary). Even with our brain’s enormous storage capacity, it wouldn’t take long to overwhelm it if we retained everything we experienced, every word we read or heard and every thought we ever had.

In order to remember something, we first have to pay attention to it. Let’s say a truck goes by but you don’t notice what is advertised on its side. You can’t possible remember it later because you never paid attention to it in the first place. As a result, many of the events we label as forgetting are more likely to be things that we never attended to in the first place.

But it’s not enough to just pay attention. You need to react to it, experience an emotion about it, think about it, and link it to previous memories. This is called ‘encoding.’ Fortunately, this process is largely automatic, unless, say, you’re trying to learn a lot of facts for a test. Then rehearsal and other memory tricks (like mnemonics) might be necessary to encode the information.

Attention and encoding alone are still not sufficient to form a memory. You also have to store it. This is where the hippocampus comes into play. It’s the part of the brain essential to lock-in the neural connections that are created when you experience something. This consolidation mostly happens during sleep when strong connections from the day (i.e., those that are in some way meaningful) are stored in memory and weak connections (i.e., incidental inputs that aren’t very relevant to your life) are dismantled and forgotten.

Finally, assuming you’ve paid attention, encoded and stored an event or fact, it doesn’t do you any good unless you can retrieve it from memory. Most of us know this one all too well. That tip-of-the-tongue experience where we know that we know the answer, but just can’t find it. The memory must be relatively strong for us to recall it without any additional cues or hints. That’s why it’s a lot easier to spot the answer when it’s presented in multiple choice format.

Those are the essentials of memory formation, but they don’t tell you anything about the quality or accuracy of those memories. It turns out that our brains do not work like cameras or tape recorders and do not store digitally precise representations. What we encode is unique to each of us as it is linked to our previous experiences and memories. That’s why you can get contradictory eye-witness reports of the same event.

To make matters worse, our memories tend to warp over time and to be changed by later experiences. In fact, each time you tell a story, your memory of it changes a little bit. After a while, your memory can shift from your visual point of view to that of one observing the entire event with you included in it. (I described this in S1E15: Vivid Memories That Aren’t).

There are also different kinds of memory, each with its own separate pathway. Episodic memory is the record of things you have experienced or done. Semantic memory records words and facts. Muscle memory stores physical routines like how to eat with a fork, walk and ride a bike. Muscle memories are among the last to leave us in late stages of dementia.

The type of memory I think we have the most trouble with is prospective memory. This is remembering to do something in the future, like going to the supermarket to buy milk. Haven’t we all thought about an errand we needed to run but then realized at the end of the day that we hadn’t done it? Or, in the example of going shopping above, bought everything else but the milk?

Knowing that memory is so fickle makes it a lot easier to understand and accept the memory mistakes we make as we get older…the kinds that are normal. I think we have a tendency to put memory on too high a pedestal and then beat up on ourselves when we fall short of the unwarranted ideal we’ve created. Don’t get me wrong: memories are very much who we are and I sure as hell don’t want to lose mine. But it’s ok not to remember things going forward because a lot of what happens is not new, novel, important or noteworthy. After all, we’ve seen and been through a lot! 

Or maybe we were distracted or otherwise occupied and just didn’t pay sufficient attention to it when it happened. I’m guilty of this one a lot. Sally will tell me something while I’m engrossed in a puzzle. The odds of my remembering it are not good.  😦

The last chapters of the book are devoted to explaining how memories can be eroded with normal aging and in dementia, along with techniques you can use to eliminate a number of memory errors. First and foremost: make lists. There is no shame in making a list, and just the act of writing the item down makes it more likely you’ll remember it without looking at the list!

The author is not a big fan of doing crossword puzzles which, she believes, only tap into stored knowledge. She much prefers that we allocate our cognitive challenge time to learning new skills because these will grow the most new brain cells and synapses. 

There’s a lot more in the book, but I’ll stop there. Here’s a link to a 14-minute TED Talk she gave which covers a lot of the same material.

Please don’t forget that you want to watch it!

__________