Idiot Brain

by Dean Burnett

  At this point, it’s important to point out that memories for things that happen to us are not the only types of memories. These are called episodic memories, or “autobiographical” memories, which should be self-explanatory. But we also have “semantic” memories, which are for information essentially without the context: you remember light travels faster than sound, but not the specific physics lesson where you learned this. Remembering that the capital of France is Paris is a semantic memory, remembering the time you vomited off the Eiffel Tower is an episodic memory.

  And these are the long-term memories we’re consciously aware of. There’s a whole swathe of long-term memories that we don’t need to be aware of like abilities we have without thinking about it, such as driving a car or riding a bike. These things are called “procedural” memories, and we won’t go into them any further because you’ll start thinking about them, and that might make it harder to use them.

  In summary, short-term memory is fast, manipulative and fleeting, whereas long-term memory is persistent, enduring and capacious. This is why a funny thing that happened while in school can be something you remember forever, and yet still decide to go into a room but, if distracted even slightly, forget why by the time you get there.

  Hey, it’s . . . you! From . . . the thing . . . that time

  (The mechanisms of why we remember faces before names)

  “You know that girl you went to school with?”

  “Can you narrow it down?”

  “You know, the tall girl. Dark blond hair but I think she was dyeing it, between you and me. She used to live in the street next to us before her parents divorced and her mother moved into the apartment that the Jones family lived in before they moved to Australia. Her sister was friends with your cousin before she got pregnant with that boy from town—that was a bit of a scandal. Always wore a red coat but it didn’t really suit her. You know who I mean?”

  “What’s her name?”

  “No idea.”

  I’ve had countless conversations like this, with my mother, gran or other family members. Clearly, there’s nothing wrong with their memory or grasp of detail; they can provide personal data about someone that would put a Wikipedia page to shame. But so many people say they struggle with names, even when they’re looking directly at the person whose name they’re trying to recall. I’ve done this myself. It makes for a very awkward wedding ceremony.

  Why does this happen? Why can we recognize someone’s face but not their name? Surely both are equally valid ways of identifying someone? We need to delve a bit deeper into how human memory works to grasp what’s really going on.

  Firstly, faces are very informative. Expressions, eye contact, mouth movements, these are all fundamental ways humans communicate.7 Facial features also reveal a lot about a person: eye color, hair color, bone structure, teeth arrangement; all things that can be used to recognize a person. So much so that the human brain has seemingly evolved several features to aid and enhance facial recognition and processing, such as pattern recognition and a general predisposition to pick out faces in random images, as we’ll see in Chapter 5.

  Compared to all this, what does someone’s name have to offer? Potentially some clues as to their background or cultural origin, but in general it’s just a couple of words, a sequence of arbitrary syllables, a brief series of noises that you’re informed belong to a specific face. But so what?

  As we have seen, for a random piece of conscious information to go from short-term memory to long-term memory, it usually has to be repeated and rehearsed. However, you can sometimes skip this step, particularly if the information is attached to something deeply important or stimulating, meaning an episodic memory is formed. If you meet someone and they’re the most beautiful person you’ve ever seen and you fall instantly in love, you’d be whispering the object of your affection’s name to yourself for weeks.

  This doesn’t usually happen when you meet someone (thankfully), so if you wish to learn someone’s name, the only guaranteed way to remember it is to rehearse it while it’s still in your short-term memory. The trouble is, this approach takes time and uses mental resources. And as we saw from the “Why did I just come in here?” example, something you’re thinking about can be easily overwritten or replaced by the next thing you encounter and have to process. When you first meet someone, it’s extremely rare for them to tell you their name and nothing else. You’re invariably going to be involved in a conversation about where you’re from, what you do for work, hobbies, what they arrested you for, that sort of thing. Social etiquette insists we exchange pleasantries on first meeting (even if we’re not really interested), but every pleasantry we engage in with a person increases the odds of the person’s name being pushed out of short-term memory before we can encode it.

  Most people know dozens of names and don’t find it takes considerable effort each time you need to learn a new one. This is because your memory associates the name you hear with the person you’re interacting with, so a connection is formed in your brain between person and name. As you extend your interaction, more and more connections with the person and their name are formed, so conscious rehearsing isn’t needed; it happens at a more subconscious level due to your prolonged experience of engaging with the person.

  The brain has many strategies for making the most of short-term memory, and one of these is that if you are provided with a lot of details in one go, the brain’s memory systems tend to emphasize the first thing you hear and the last thing you hear (known as the “primacy effect” and “recency effect,” respectively),8 so a person’s name will probably get more weight in general introductions if it’s the first thing you hear (and it usually is).

  There’s more. One difference between short- and long-term memory not discussed so far is that they both have different overall preferences for the type of information they process. Short-term memory is largely aural, focusing on processing information in the form of words and specific sounds. This is why you have an internal monologue, and think using sentences and language, rather than a series of images like a film. Someone’s name is an example of aural information; you hear the words, and think of it in terms of the sounds that form them.

  In contrast to this, the long-term memory also relies heavily on vision and semantic qualities (the meaning of words, rather than the sounds that form them).9 So a rich visual stimulus, like, say, someone’s face, is more likely to be remembered long term than some random aural stimulus, like an unfamiliar name.

  In a purely objective sense, a person’s face and name are, by and large, unrelated. You might hear people say, “You look like a Martin” (on learning someone’s name is Martin), but in truth it’s borderline impossible to predict accurately a name just by looking at a face—unless that name is tattooed on his or her forehead (a striking visual feature that is very hard to forget).

  Let’s say that both someone’s name and face have been successfully stored in the long-term memory. Great, well done. But that’s only half the battle; now you need to access this information when needed. And that, unfortunately, can prove difficult.

  The brain is a terrifyingly complex tangle of connections and links, like a ball of Christmas-tree lights the size of the known universe. Long-term memories are made up of these connections, these synapses. A single neuron can have tens of thousands of synapses with other neurons, and the brain has many billions of neurons, but these synapses mean there is a link between a specific memory and the more “executive” areas (the bits that do all the rationalization and decision-making) such as the frontal cortex that requires the information in the memory. These links are what allows the thinking parts of your brain to “get at” memories, so to speak.

  The more connections a specific memory has, and the “stronger” (more active) the synapse is, the easier it is to access, in the same way that it’s easier to travel to somewhere with multiple roads and transport links than to an abandoned barn in the middle of a wilderness. The name and f
ace of your long-term partner, for example, is going to occur in a great deal of memories, so it will always be at the forefront of your mind. Other people aren’t going to get this treatment (unless your relationships are rather more atypical), so remembering their names is going to be harder.

  But if the brain has already stored someone’s face and name, why do we still end up remembering one and not the other? This is because the brain has something of a two-tier memory system at work when it comes to retrieving memories, and this gives rise to a common yet infuriating sensation: recognizing someone, but not being able to remember how or why, or what their name is. This happens because the brain differentiates between familiarity and recall.10 To clarify, familiarity (or recognition) is when you encounter someone or something and you know you’ve done so before. But beyond that, you’ve got nothing; all you can say is this person/thing is already in your memories. Recall is when you can access the original memory of how and why you know this person; recognition is just flagging up the fact that the memory exists.

  The brain has several ways and means to trigger a memory, but you don’t need to “activate” a memory to know it’s there. You know when you try to save a file onto your computer and it says, “This file already exists”? It’s a bit like that. All you know is that the information is there; you can’t get at it yet.

  You can see how such a system would be advantageous; it means you don’t have to dedicate too much precious brain power to figuring out if you’ve encountered something before. And, in the harsh reality of the natural world, anything that’s familiar is something that didn’t kill you, so you can concentrate on newer things that might. It makes evolutionary sense for the brain to work this way. Given that a face provides more information than a name, faces are more likely to be “familiar.”

  But this doesn’t mean it’s not intensely annoying for us modern humans, who regularly have to make small talk with people we’re certain we know but can’t actually recall right now. That’s the part most people can relate to, the point where recognition turns to full-on recall. Some scientists describe it as a “recall threshold,”11 where something becomes increasingly familiar, until it reaches a crucial point and the original memory is activated. The desired memory has several other memories linked to it, and these are being triggered and cause a sort of peripheral or low-level stimulation of the target memory, like a darkened house being lit by a neighbor’s fireworks display. But the target memory won’t actually activate until it is stimulated above a specific level, or threshold.

  You’ve heard the phrase “it all came flooding back,” or you recognize the sensation of a quiz answer being “on the tip of your tongue” before it suddenly occurs to you? That’s what’s happening here. The memory that caused all this recognition has now received enough stimulation and is finally activated, the neighbor’s fireworks have woken those living in the house and they’ve turned all the lights on, so all the associated information is now available. Your memory is officially jogged, the tip of your tongue can resume its normal duties of tasting things rather than providing an unlikely storage space for trivia.

  Overall, faces are more memorable than names because they’re more “tangible,” whereas remembering someone’s name is more likely to require full recall than simple recognition. I hope this information means that you’ll understand that if we ever meet for a second time and I don’t remember your name, I’m not being rude.

  Actually, in terms of social etiquette, I probably am being rude. But now at least you know why.

  A glass of wine to refresh your memory

  (How alcohol can actually help you remember things)

  People like alcohol. So much so that alcohol-related issues are an ongoing problem for many populations. These issues can be so widespread and constant that dealing with them ends up costing billions.12 So why is something so damaging also so popular?

  Probably because alcohol is fun. Aside from causing a dopamine release in the areas of your brain dealing with reward and pleasure (see Chapter 8), thus causing that weird euphoric buzz that social drinkers enjoy so much, there’s also social convention built up around alcohol; it’s almost a mandatory element of celebration, bonding and just general recreation. Because of this, you can see why the more detrimental effects of alcohol are regularly overlooked. Sure, hangovers are bad, but comparing and laughing about the severity of respective hangovers is yet another way of bonding with friends. And the ridiculous ways in which people behave when drunk would be deeply alarming in some contexts (in a school, perhaps, at 10 a.m.) but when everyone does it, it’s just fun, right? A necessary relief from the seriousness and conformity demanded of us by modern society. So, yes, the negative aspects of alcohol are considered a price worth paying by those who enjoy it.

  One of these negative aspects is memory loss. Alcohol and memory loss go hand in unsteady hand. It’s a comedy staple in sitcoms, stand-up and even personal anecdotes, usually involving someone waking up after a drunken night and finding himself in an unexpected situation, surrounded by traffic cones, unfamiliar garments, snoring strangers, irate swans and other things that wouldn’t be in a person’s bedroom under normal circumstances.

  So how then can alcohol possibly actually help your memory, as the title of this bit suggests? Well, it’s necessary to go over why alcohol affects our brain’s memory system in the first place. After all, we ingest countless different chemicals and substances every time we eat anything, why don’t they cause us to slur our words or pick fights with lamp-posts?

  It’s due to the chemical properties of alcohol. The body and brain have several levels of defence to stop potentially harmful substances entering our systems (stomach acids, complex intestinal linings, dedicated barriers to keep things out of the brain . . .) but alcohol (specifically ethanol, the type we drink) dissolves in water and is small enough to pass through all these defences, so the alcohol we drink ends up spread throughout our bodily systems via the bloodstream. And when it builds up in the brain, several bags of wrenches are thrown into some very important workings.

  Alcohol is a depressant.13 Not because it makes you feel dreadful and depressed the next morning (although, good lord, it does), but because it actually depresses activity in the nerves of the brain; it reduces their activity like someone lowering the volume on a stereo. But why would this make people behave in more ridiculous ways? If brain activity is reduced, shouldn’t drunk people just sit there quietly and drool?

  Yes, some drunk people do precisely this, but remember that the countless processes the human brain is carrying out every waking moment require not just making things happen, but preventing things from happening. The brain controls pretty much everything we do, but we can’t do everything all at once, so much of the brain is dedicated to inhibition and stopping activation of certain brain areas. Think of the way traffic is controlled in a large city; it is a complex job, relying on stop signs or red traffic lights to some degree. Without them the city would grind to a messy halt in a matter of minutes. Similarly, the brain has countless areas that provide important and essential functions but only when needed. For example, the part of your brain that moves your leg is very important, but not when you’re trying to sit in a meeting, so you need another part of the brain to say, “Not now, buddy,” to the leg-controlling part.

  Under the influence of alcohol, the red traffic lights are dimmed or switched off in the brain regions that normally keep giddiness, euphoria and anger in check or suppressed. Alcohol also shuts down the areas responsible for speech clarity or walking coordination.14

  It is worth noting that our simpler, fundamental systems, controlling things such as heart rate, are deeply entrenched and robust, whereas the newer, more sophisticated processes are more easily disrupted or damaged by alcohol. There are similar parallels in modern technology; you could drop a 1980s Walkman down a flight of stairs and it might still work, but tap a smartphone on the corner of a table and you end up with a hefty repair bill. Sophistic
ation results in vulnerability, it seems.

  So with the brain and alcohol, “higher” functions are the first to go. Things like social restraint, embarrassment and the little voices in our head that say, “This probably isn’t a good idea.” Alcohol silences these pretty quickly. When you’re drunk you’re more likely to say what’s on your mind or take a crazy risk just to get a laugh, such as agreeing to write an entire book about the brain.15

  The last things to be disrupted by alcohol (and it has to be a lot to get to this point) are the basic physiological processes, such as heart rate and breathing. If you’re so drunk you get into this state, you’ll probably lack sufficient brain function to be capable of being worried, but you really really should be.16

  Between these two extremes, there’s the memory system, which is technically both fundamental and complex. Alcohol seems to have a particular tendency to disrupt the hippocampus, the main region for memory formation and encoding. It can also limit your short-term memory, but it’s the long-term memory disruption via the hippocampus that causes the worrying gaps when you wake up the next day. It’s not a complete shutdown of course; memories are usually still being formed, but less efficiently and more haphazardly.17

  Interesting aside: for most people, drinking enough to block memory formation completely (alcoholic blackouts) would mean they’re so intoxicated they can barely speak or stand. Alcoholics, however, are different. They’ve been drinking a lot for a long time, so much so that their bodies and brains have actually adapted to deal with, and even require, a regular alcohol intake, so they can remain upright and coherent (more or less) despite consuming way more alcohol than your average person could withstand (see Chapter 8).