She’s your favorite actress. You’ve been following her career since she was in her early teens. You know her face with as much familiarity as family members. You can see the time she was being interviewed on the red carpet and gave her passing co-star a high five in your minds eye photographically.
But suddenly, when you’re talking with friends about movies at a bar or restaurant and you start to say something about her, you realize with something approaching horror that you can’t think of her name. It’s ridiculous — you know you know it, you just can’t find it in the wiring for some strange reason.
You’ve just suffered the disconcerting phenomenon of “lethologica” (from the Ancient Greek terms for “forgetfulness” and “relating to thought or reason”), more commonly called “tip of the tongue.” It’s characterized by the feelings that recall is imminent and frustration at it being out of reach, and it’s different from plain old forgetting because we can often recall features of the word or phrase we’re looking for like the letter it starts with, it’s rhythm or length or words that sound or mean something similar.
It feels for all the world like a tiny little software agent running around in the brain, searching through file drawers with great determination, foiled because of some past clerical error.
But what’s the brain actually doing, and what can tip of the tongue (TOT) phenomenon teach us about the way memory works?
Thanks For The Memory
Knowing we know something but not knowing it right at that moment sounds kinds of counter-intuitive, and if we didn’t all experience it during many a party or dinner conversation we’d hardly believe it was possible. Surely you know something or you don’t — if you don’t have it at immediate recall, what makes you so sure it’s there somewhere just waiting to be found?
It’s all got to do with a property called “metamemory.” As the word suggests, we have an overarching awareness of what we know and what we don’t. Someone might ask where you had your last holiday and even though you can’t recall the name of the country right then and there, you know you’d recognize it on a map — you know it, and you know you know it.
By the same token, say someone asked you who invented the sextant. Unless you’re an expert on pre-industrial age sailing you probably have an immediate awareness that’s it’s something you don’t know. Like an index card system, you know the contents of your memory, and recalling a word, person, event, or anything else is a matter of sending a command to go and get it.
It’s about the difference between the “state” of memory recall and the “item” you’re recalling. As Dr. James Giordano, professor of neurology at Georgetown University Medical Center puts it, the state is the feeling of retrieving a memory, and the item is the factoid that eludes the state that seeks it.
So in the decades since we’ve given up on the persistent Cartesian theater/homunculus model, is there a little messenger racing around the brain shining a little torch into dark corners of neural maps while you sit there drumming the table, frowning and repeating, “Oh … what’s her name again?!?”
According to professor and Howard Hughes Medical Institute Investigator, UCSF School of Medicine, Dr. Loren Frank, we still don’t really know, but he says it involves propagating waves of activity through neocortical structures and likely the hippocampus where a search pattern is generated. “The network generates a new pattern as output, and then some sort of comparison is done to determine whether the new pattern corresponds to the correct one,” he says.
Giordano adds that network characteristics of groups of neural units — both neurons and glial cells — are established, both functionally and to some extent structurally as memories are consolidated. “It’s the spatio-temporal pattern of network activities that recur, at least in part, during memory retrieval and linking,” he says.
Tip of the tongue phenomena might reflect only partial activation of these memory-processing networks, with a relative incompleteness to “complete the loop” and access the information to the extent desired. Giordano refers to work by neurologist Antonio Damasio, who referred to the “software running around your head” feeling being what happens when existing networks are deferentially engaged in attempts at cognitive processing.
Feeling It
But as anyone who’s ever floundered to remember the player who scored the winning goal or the city our grandparents immigrated from (ie all of us) knows, the tip of the tongue phenomena has a strong emotional dimension. The Wikipedia entry on the phenomenon refers to “mild anguish while searching for the word, and a sense of relief when the word is found.”
Frank says TOT is an emotional experience because of what it might represent to us about our brain. “My guess is it feels stronger because it occurs for items that are very familiar and that we know well,” he says. “So there’s both a feeling of things not working as well as a strong representation once the right word comes up.”
It’s also the case that what we’re trying to remember can be exacerbated by emotional ties — even if it’s the drive to not look like an idiot in front of others by forgetting something so obvious.
But we should remember that memory and emotion are two sides of the same coin. Memories are more likely to be cemented over long term if they mean something to us emotionally, and as Damasio notes, emotion is the cognitive interpretation of signals produced by our bodily (and cerebral) responses to various stimuli.
