Animals in Translation (32 page)

Dr. Mineka also found she could protect an animal from developing a fear the same way. If she first exposed a lab-reared monkey to another lab-reared monkey
not
acting afraid of a snake, that gave him “immunity.” After that, if he saw a wild-reared monkey acting scared of the snake, he did
not
develop snake fear himself. He held on to his first lesson.

L
EARNING BY
W
ATCHING

This is called
observational learning.
When it comes to
evolutionary fears,
as well as to many other areas of learning, animals and people learn by watching what other animals or people do, not by doing something themselves and learning from the consequences. I have the impression this lesson hasn't quite been absorbed by most educators. You read that hands-on learning is best, but that may not always be so. Obviously evolution has selected for strong observational learning in animals and in humans. One of the most amazing examples of this is in Frans de Waal's book
The Ape and the Sushi Master.
Dr. de Waal says that in Japan, apprentice sushi cooks spend three years just
watching
the sushi master prepare sushi. When the apprentice finally prepares his first sushi, he does a good job of it.
²¹

Dr. Mineka's research shows how people and animals can develop phobias without ever having had a bad experience with the thing they're afraid of. Classical learning theory always assumed people learn phobias through direct experience. That's logical, but
it doesn't correspond to reality, because lots of phobic people can't remember any initial bad experience. Probably most people with fear of flying, just to give a common example, have never come close to crashing.

So a lot of therapists had suspected that phobias are contagious, that people can “catch” a phobia by hanging around people who already have it. Dr. Mineka's research showed that not only is it possible to learn a phobia by being exposed to someone else who has that phobia, it's incredibly natural and easy to acquire a phobia this way. Fear is contagious.

The fact that animals learn what to be afraid of from watching other animals is another example of evolution giving animals and people an ability to ward off trouble before it happens. If you're Mother Nature and you decide to set things up so everybody learns what to be afraid of through direct, hands-on personal experience, you're going to lose a lot of animals. The only monkeys you'd have around to propagate the species would be monkeys who'd had the good luck never to meet up with a snake in the first place, or monkeys who did meet up with a snake and lived to tell the tale. The odds of keeping monkeys on the planet are going to be a lot higher if you set things up so monkeys learn about snakes from other monkeys.

A
N
E
LEPHANT
N
EVER
F
ORGETS

Of course, it's not going to be much use learning about snakes in the safety of your monkey community if you don't remember what you know the next time you run into one. What happens if your monkey elders tell you snakes are bad news, and it slips your mind?

When you think about how much stuff you've forgotten in your life (quick! what's the quadratic equation?) it's kind of horrifying to think that our survival depends on
remembering
all the bad stuff we're supposed to be afraid of.

Evolution solved that problem by making fear learning
permanent.
All intensely emotional learning is permanent. That's why you can forget everything you ever learned in trigonometry, but no one born before 1958 is ever going to forget where they were when Kennedy was shot, and no one born before 1996 is ever going to
forget where they were on September 11. You couldn't forget where you were even if you wanted to, and even if you tried to.

The story is a little different with lesser traumas and fears. Animals and people certainly act as if they can forget a milder fear, and in the past behaviorists did quite a bit of research on this. Typically researchers would teach an animal to be afraid of something neutral, such as a light or a tone; then teach the animals to stop being afraid of the light or tone. They did this by pairing the
conditioned stimulus,
which was the light or the tone, with something aversive, like a shock to the foot or a puff of air to the eye.

Under those conditions, pretty quickly an animal would start reacting fearfully to the light or the tone, at which point the experimenters stopped pairing the light or tone with anything bad. Sure enough, after a while the animals stopped reacting badly to the light or the tone. Behaviorists called this phenomenon
extinction,
because they had extinguished the response. The animals seemed to have forgotten that lights or tones were scary. Researchers found the same thing in humans.

However, it turns out that extinction doesn't actually wipe out the fear from your brain. It's still there. If you teach an animal to fear a tone that precedes an air puff to the eye, and then teach him not to fear the tone because there's no more air puff, he hasn't forgotten. He stops blinking reflexively every time he hears the tone, but all you have to do to get him blinking again is to pair the tone with the air puff again just
once
and the animal is right back where he started. He
knows
that tone means air puff. He hasn't forgotten.

Both animals and people can “get over” a learned fear. But today we understand that getting over a fear isn't the same thing as forgetting a fear.
Extinction
isn't forgetting; it's
new learning that contradicts old learning.
Both lessons—tone is neutral and tone is bad—stay in emotional memory.

F
AST
F
EAR
, S
LOW
F
EAR

When you spend a lot of time with animals it's easy to see that animal fears are worse than human fears a lot of the time. It's also easy to see that you, as a human, share certain core fears with animals.

Cows don't like snakes, and neither do you. You and any cow you meet see eye-to-eye on that one.

But beyond that, it's hard for people to empathize with an animal's fears. A lot of times it's hard even to know what an animal's fears
are.
I get a lot of calls from people who can't figure out what's getting their animals so upset. I'll go out to a plant that's having problems and find the manager standing there in the middle of what looks like a perfectly normal, perfectly safe feedlot to
him,
and he's got a couple hundred head of cattle having conniptions. He has no idea why.

To understand animal fears it pays to know something about the brain. One of the most important researchers in the neurology of fear is Joseph LeDoux of New York University. In his book
The Emotional Brain,
Dr. LeDoux explains that fear happens in the amygdala.
²²
What's really interesting for nonscientists is that he's found there are two kinds of fear in the brain:
fast fear
and
slow fear,
which he calls the
low road
and the
high road.

The high road gives you slow fear for a simple reason: its physical path through the brain is longer than the low road. On the high road, a scary stimulus, such as the sight of a snake in your path, comes in through the senses and goes to the thalamus, located deep inside the brain. The thalamus directs it up to the cortex, at the top of the brain, for analysis. That's why Dr. LeDoux calls slow fear the high road. The information has to travel all the way up to the top of the brain. When it gets there the cortex decides that what you're looking at is a snake, then sends this information—it's a snake!—back down to the amygdala, and you feel afraid. The whole process takes twenty-four milliseconds.

The low road takes
half
the time. Using the fast fear system, you see a snake in your path, the sensory data goes to your thalamus, and from there it goes directly over to your amygdala, which is also located deep inside the brain, in the temporal lobes at the side of your head. The whole process takes twelve milliseconds. Dr. LeDoux calls fast fear the low road because the sensory information doesn't have to travel up to the top of the brain. The cortex is out of the loop.

Both systems operate at the same time, with the same sensory inputs. This means that the thalamus receives potentially frightening
sensory data and sends it two places: both to the cortex
and
to the amygdala. If you're looking at a snake, the fast fear system has you jumping out of the way in twelve milliseconds; then, twelve milliseconds later, you get a second jolt of fear from the exact same information finally arriving at the amygdala after having been routed through the cortex for closer analysis.

Dr. LeDoux thinks the reason our brains are set up to work this way is that evolution couldn't put both speed and accuracy into the same system. The fast road, he says, is quick and dirty. You're walking down a path, you see something long, thin, and dark in the path, and your amygdala screams,
“It's a snake!”
Twelve milliseconds later your cortex has the second opinion: either,
“It's
definitely
a snake!”
or, “It's just a stick.” That doesn't sound like very much time, but it makes all the difference in the world to whether you get bitten by that snake or not, assuming it is a snake and not a stick. The reason fast fear can be so fast is that accuracy is sacrificed for speed. Fast fear gives you a rough draft of reality.

It's the cortex that does the precision rendering of the world, so it's the cortex that can tell a snake from a stick. But that takes time, and time is exactly what you don't have when you're looking at a snake. Dr. LeDoux thinks nature evolved this system because it's better to be safe than sorry: it's better to mistake a stick for a snake than to keep walking toward a snake bite while your cortex is still forming an opinion.

The other thing to know is that high road fear is conscious, while low road fear is not. High road fear is conscious because it's been through the cortex, which makes you consciously aware of what's scaring you.
I'm scared of that snake sitting there in the middle of the road.
That's conscious, high road fear. With low road fear you react unconsciously, or mindlessly. You're running away before you know what you're running away
from.

W
EIRD
F
EAR

One of the really interesting things about memory is that
conscious memory
is much more fragile than
unconscious memory.
The terminology for different kinds of memory gets confusing, partly because different fields use totally different terms for conscious and uncon
scious memory. Some fields talk about
declarative
versus
procedural
; other fields talk about
explicit memory
versus
implicit memory.
I'll mostly stick to conscious and unconscious, but when it makes sense to use other terms, I will.

Conscious memory handles the kinds of things we call “school learning,” facts, figures, dates, names, and so on. If you think about how much of what you learned in school you've forgotten you'll get a good idea of how fragile it is. Unconscious learning is
much
more stable and long-lasting. The old saying about how you never forget how to ride a bicycle is a perfect example. It's true: you
don't
ever forget how to ride a bicycle once you've learned.
²³
You can have significant brain damage from a stroke, and you're
still
likely to remember how to ride a bicycle. It's very tough to wipe out unconscious memory.

By now you're probably thinking Freud was right. If so, you're not far off. A number of Freud's ideas are turning out to be pretty good descriptions of how the brain works. I'm no expert on Freud, so I should add that I have no idea whether Freud's idea of repression will be supported by brain research. What
is
supported is the idea that we have a huge amount of unconscious information stored up in our brains.

I don't know whether unconscious, or procedural, learning like bicycle riding is always permanent. The easy way to remember what procedural memory is, is to think of things like bicycle riding as
procedures.
When you learn something like riding a bicycle, or how to button and unbutton your shirt, you're using unconscious, procedural memory. Your fingers know how to unbutton your shirt; you can do it without thinking about it consciously.

I don't know whether procedural learning is always permanent, but it looks like fear learning is. Learned fears are the exact opposite of learned facts, dates, and names, which you're constantly forgetting. You never forget a fear. In fact, fear learning in animals and people is so powerful it can get stronger over time, even when you do nothing further to “practice” your fear through repeat exposure. Say you see a snake in the road just once in your life, and it scares you half to death; you could never see a live snake again yet
still
get more and more frightened of snakes as time goes on.

According to Dr. LeDoux, the relative weakness of conscious fear
memory compared to unconscious fear memories may explain why fears can spread so far beyond their original content. What may happen is that as time passes you lose your conscious memory of the thing that frightened you, but
your unconscious memory is as strong as ever.

Dr. LeDoux gives a nice example of a person in a bad car crash where the horn gets stuck on. For a period of time after the crash, the person feels frightened all over again every time he hears a horn. But then, over time, he gradually forgets about the car horn, because the details of the car crash are fading out of his conscious memory. He doesn't consciously remember he's afraid of car horns.