Remember: The Science of Memory and the Art of Forgetting

by Lisa Genova

LIFE-LOG.

Your episodic memories are chock-full of distortions, additions, omissions, elaborations, confabulations, and other errors.

For every step in memory processing—encoding, consolidation, storage, and retrieval—your memory for what happened is vulnerable to editing and inaccuracies.

we can only introduce into the memory creation process what we notice and pay attention to in the first place.

my memory for what happened last Christmas morning will be different from what my son remembers, and neither his memory nor mine will contain the full picture—the whole truth, so to speak.

Once stored, memories for what happened still aren’t safe from alteration.

memories can decay with the passage of time. The physical neural connections can literally retract and disappear, erasing part or all of your memory of what happened.

every time we retrieve a stored memory for what happened, it’s highly likely that we change the memory.

when we retrieve a memory of something that happened, we are reconstructing the story, not playing the videotape.

Every time we recall an episodic memory, we overwrite it, and this new, updated edition is the version we’ll retrieve the next time we visit that memory.

after several recalls of any given episodic memory, it has the potential to deviate quite a bit from the original.

an episodic memory becomes vulnerable to outside influences every time we retrieve it, false information can also worm its way in every time we recall something, deforming the memory of what we experienced.

it’s quite easy to manipulate episodic memory with language and misleading questions,

people watched a thirty-second video of a bank robbery. Twenty minutes later, half of the subjects were given five minutes to write down what they saw. The other half were kept busy for an equivalent amount of time on an unrelated task. Then, everyone was asked to pick out the bank robber from a lineup. Among the nonwriters, 61 percent picked out the robber, but only 27 percent of the writers did. Note that not even a half hour later, at best only about two-thirds of people who witnessed the bank robbery could remember correctly what the robber looked like. And writing about what they had seen dramatically compromised their ability to accurately remember what they had witnessed only a few minutes earlier.

Writing something down allows you to rehearse and therefore strengthen the memory for the details you choose to write about, but this action can also unwittingly prevent you from rehearsing, and therefore later remembering, any details you didn’t include. Putting any sensory experience into words distorts and narrows the original memory of the experience.

One of the most common experiences of memory failure is known as blocking or tip of the tongue (TOT).

All words have neural representations and associated connections in your brain. Some neurons store the visual aspects of words—what they look like as printed letters. Other neurons store the word’s conceptual information—what the word means, every sensory perception and emotion associated with it, any past experience you’ve had with it. Others are in charge of phonological information. These neurons hold what the word sounds like when spoken and are necessary for the verbal pronunciation of the word, either aloud or in your head.

Blocking can occur when there is only partial or weak activation of the neurons that connect to the word you’re looking for. What’s her name? I can tell you it begins with an L but nothing else. Without more neural activation, I get stuck there.

During a TOT experience, we sometimes get a sneak peek of the word in question by way of the first letter or the number of syllables. We often experience a partial retrieval, these encouraging, yet wimpy hints. I know it begins with a D.

decoys cause you to shift your attention, enticing you to follow neural pathways that lead to them and not to the word you really want.

If I hadn’t offered my incorrect guess, Joe’s brain might have found the surfer straight away.

When you’re in a TOT state and the target word is presented, you don’t wonder if it’s the right answer or need some time to consider it or fact-check. You call off the hunt right there. Hallelujah.

Blocking on a person’s name is one of the most frequent kinds of memory retrieval failure for all of us. And it’s normal. Being in a TOT state does not mean you have Alzheimer’s.

The average twenty-five-year-old experiences several TOTs per week. But young people don’t sweat them, in part because memory loss, Alzheimer’s, old age,...

because young people today have been tethered to devices since childhood, they don’t hesitate to outsource the job to their smartphones. They seldom suffer in TOT misery for hours (or even minutes) like their parents, who stubbornly insist on recalling th...

You are not more likely to experience fewer TOTs, resolve future TOTs faster, better remember where you put your keys, remember to take your heart medication tonight, or prevent Alzheimer’s if you can retrieve Tony Soprano’s name without Google.

TOTs are a normal glitch in memory retrieval, a by-product of how our brains are organized.

The neural architecture that supports baker as a profession is stronger because it has many more elaborate connections and possible neural roads for activation—words, memories, associations, and other meaning—cues that can trigger the word baker in response to “Who is this guy?”

Compared to the name baker

The Baker/baker paradox also explains why so many of us are bad at remembering names but not at recalling other details about a person.

Prospective memory is your memory for what you need to do later.

prospective memory is so poorly supported by our neural circuitry and so steeped in failure, it can almost be thought of as a kind of forgetting rather than a kind of memory.

For a prospective memory to be remembered and not forgotten, the intention or the action that needs to be performed later needs first to be encoded into memory now. This step rarely presents a problem. I need to remember to book my daughter’s flight home from college before I go to bed tonight. There. I’ve asked my brain to remember to do this task.

generally speaking, our brains are terrible at remembering to remember.

Prospective memories rely on external cues to trigger their recall.

because we sometimes set up not-so-great cues or miss the cues when we’re supposed to notice them, this kind of memory is highly susceptible to failure.

Prospective memory is that flaky friend who likes to make plans with you to meet for drinks but half the time is a no-show.

Prospective memory is challenging for people of all ages (does your teenager ever remember to shut off the bedroom light when leaving the room?)

MAKE TO-DO LISTS. We can create external aids for our prospective memory.

Think of to-do lists as glasses for your prospective memory.

airplane pilots don’t rely on their fickle prospective memories to remember to lower the wheels before landing the plane. Thankfully, they use checklists.

ENTER THE INFORMATION INTO YOUR CALENDAR. The retention intervals for prospective memory can be challenging. If you have to remember to bring a check to your daughter’s dance class next week, holding this intention in your conscious awareness for the next seven days is both impractical and impossible.

I do this all the time

BE SPECIFIC ABOUT YOUR PLAN.

tell yourself, “I’m going to go to yoga at noon.” Now you have what psychologists call an implementation intention. Place your yoga mat by the front door. There’s your visible cue. Enter “yoga at noon” into your calendar, and set a reminder alert to go off at 11:45 because you know it takes ten minutes to drive there. Namaste.

PLACE YOUR CUES IN IMPOSSIBLE-TO-MISS LOCATIONS.

BE AWARE IF YOUR ROUTINE HAS BEEN DISRUPTED.

If you don’t revisit the memory, if it just sits on your brain’s cortical shelf like an old trophy collecting dust, that memory will erode with the passage of time.

If you do you change it..if u not u forget

after twenty-four hours, forgetting leveled off to a retention rate of about 25 percent. Called the Ebbinghaus forgetting curve, this pattern is generally what happens to unsupported memory over time.

Without deliberate attempts or strategies to retain what you learn, you will forget most of what you experience almost right away.

according to Ebbinghaus and his forgetting curve, although the information we encode into memory degrades rapidly with the passage of time, it doesn’t entirely disappear.

recent studies have shown that if the collection of synapses representing a memory isn’t activated over time, the connections will be physically pruned away. If dormant for too long, neurons will literally retract their anatomical, electrochemical connections with other neurons.