Read The Universal Sense Online
Authors: Seth Horowitz
A friend of Lance’s was the happy father of two rather hyperactive children, and as most parents do, he was complaining about the impossibility of getting the kids to sleep without recourse to medication or a baseball bat lovingly wielded. He had heard about some of our work and asked us very straightforwardly whether we could come up with some way to make his kids calm down enough in the evening to go to sleep.
Now, sleep is a really complicated phenomenon. We don’t really know what it’s for, how it works, or why it’s so prevalent in any organism with more than two ganglia to rub together, but having worked in a chronobiology lab for several years, I knew about one of the biggest problems involved in all long-distance trucking—that of falling asleep at the wheel. Driving anything from a train to a car should be able to give you enough motivation to stay alert so that you are not awakened by hideous crashing sounds. But falling asleep on long hauls is very common—so common that a lot of grant money is spent on industrial research into monitoring driver alertness. You can even find little electronic head-mounted devices that shriek unpleasantly at you if your head drops below a certain angle, as happens with most people who nod off.
The underlying principle behind falling asleep at the wheel is rather surprising. It’s not exhaustion or attentional issues, although these can contribute. It’s actually due to the fact that your vestibular system, the balance part of your inner ear, is extensively connected to your arousal centers as well as centers that affect non-voluntary things such as salivation and gastric control. You’ve probably had some experience with this if you’ve ever gotten on a boat in high seas or on a really high-speed roller coaster—your vision can’t keep up with your inner ear’s signals and you get sensory dissonance, which leads to motion sickness. But nauseogenic motion sickness (the type that makes you want to redeposit your lunch) is only one form. Low-amplitude, low-frequency pseudo-random vibrations, the kind experienced while driving even on a relatively smooth road, yields another form of motion sickness called Sopite syndrome, which leads to extreme tiredness and sleepiness, no matter how important it is that you stay awake. Few people have heard of this, although the effect itself is relatively common knowledge among parents of infants—it’s the reason you can rock your child to sleep. The low-amplitude, low-frequency oscillations lull the child and she drifts off. My parents used it by depositing me into the backseat of my father’s old suspension-challenged VW bug and driving me around a local dirt road for half an hour, which worked even better.
An interesting feature of Sopite syndrome is that it can affect passengers much more than drivers, and it is possible that our old friend the efference copy is responsible—if you are driving, you have at least some control over the car’s motion, and the rocking and shaking have to go on for much longer to get to you. (The clearest example I ever had of this was on the second date with my fiancée-to-be, when after about an hour’s drive
she nodded off. I felt touched that she was so trusting of my driving ability, when in fact years of married travel experience later showed me that she was just really sensitive to Sopite-type stimulation. Romance and science are often at odds.)
So, weighted down with papers based on years of research at NASA, NIH and military organizations we set out to figure out how to make hyperactive kids sleep. But because we were doing this as a personal experiment (i.e., weren’t being paid for it) and were pressed for time, rather than compose original music we decided to just mix our modulations into some old recordings of classical music tracks. This was an interesting challenge, as we needed to make subtle changes in amplitude at the right rates but not change the overall sound of the piece. After all, Dad was not telling the kids that he was selling their souls to science; he just was going to put on a CD of “boring” classical music in the hopes that they might calm down. This had been tried in the past with about as much success as you might think. The problem was that when we tested it on my very Sopite-syndrome-sensitive wife, there was no effect. So we stepped out of the realm of algorithm and into the real world of recorded sound. We placed a geophone, a very low-frequency microphone used to record earthquakes, in the back of my car and drove around for twenty minutes, then extracted the envelope from that sound, convolved it into three different classical pieces, and handed it off to the weary father with our fingers crossed.
The next day he told us that he’d tried the first track and it hadn’t worked. Feh.
But the day after that he called us up and announced we were geniuses because both the kids had slid off to sleep within minutes after he put on the second track. We were pleased to have our genius recognized, but it was a bit confusing. The songs
were about the same acoustic density and had similar keys, instruments, lengths, and volumes, and we had applied the same algorithms. Why did one track have no effect and the other two tracks worked so well that the disk ended up being called “the going-to-sleep CD” by one of the kids? For a reason that highlights one of the big problems of brain hacking: that all brains and all individual brains’ experiences are different. It turns out that these particular hyperactive kids were enthralled with a thrash metal version of the first track that they had heard on the Internet, and it was in fact one of the things that made them bounce around like Tasmanian devils on speed. So while the algorithms were there and were clearly effective as sleep inducers in the other two tracks, the kids’ previous experience with the basic musical structure of the first piece in a high-speed and exhilarating version had overridden the relatively subtle signals that the modulations provided. And as I’ve stated before, that’s one of the problems (and, on the consumer side, comforting factors) with brain hacking of any sort: if it is based on statistical models of how the brain works (which is what neuroscience is largely based on), while it may work on most people, it isn’t going to work on everyone.
So how can we use brain hacks in the many facets of our lives? I started playing with targeted auditory brain hacking in 2000, trying to figure out how it could be used legally. At the time we were the only ones really doing it. And our first idea was advertising. After all, advertising has been around since the first multicellular organism grew something showy to impress its swampmates about its fitness or its ability to defend its territory. It’s been a principal part of human communication since the first exaggerated bone sculpture that showed a hyper-fertile female form (“Come to Ogg’s cave for a good time. Mammoth
parking out back”). And even in its more contemporary sense, advertising is about getting an emotional hook into potential consumers to convince them that they desperately need something that they never even knew existed until they saw or heard the ad, lest they be unattractive, unhireable, or just out of the loop. Without getting into a long discussion of the idea of consumer psychology and the new field of neuroeconomics, advertising, especially successful advertising, is based on fairly solid psychological ground. It’s about making you buy stuff. And one of the key points about any purchase is that almost all purchases are emotional. When we decide to go out and buy a new music or media player, few of us really spend hours researching the latest electronics, checking specifications, comparing how flat the frequency spectrum of the headphones is, or whether its maximum volume violates OSHA or health guidelines. We buy it because it looks cool or our friends have it. Despite all the outrage over the recent introduction of a music player targeted to women (the difference was not that it preferentially lateralized speech to the right ear or had a slightly different frequency response, but rather it that only came in pink), that marketing decision had a reason behind it—it sold to the target demographic.
Advertising is based largely on coming up with catchy phrases and jingles to push a consumer toward an emotional need for an item that she could probably live without. The idea is to convince you that you really need the Omniglot 4000 Home Pork Puller with salad shooter because without it you will be unattractive, have questionable hygiene, and will probably die of restless eyebrow syndrome. But ads are supposed not only to convince you that you need something but to use psychological tools to help you remember the item’s name and be hooked into the idea that only
that
particular brand will give you what you
need. In short, the aim is to manipulate a consumer’s emotions, memory and attention by getting the ads to stick with you, using basic psychological principles (repetition is the heart of memorization, sex sells, etc.). And if you doubt for one second that these basic principles work, well, how come you remember exactly what comes after “My bologna has a first name”?
But no one in the 1960s was using advanced neural algorithms to plot control of the consumer mind. They were just using what had worked in the past, and sometimes they got it just right. They set out to create catchy jingles, but by an accidental confluence of factors ranging from familiarity to musical key to rhythms, they wound up making earworms (or “auditory perseverates” in neurospeak)—musically linked phrases that are almost impossible to get out of your head. Earworms can be as simple as a nursery rhyme phrase stuck in your head for a few minutes or as complex as the opening four measures of Bruce Springsteen’s “Thunder Road” cycling through your brain for five solid days until you are ready to nuke New Jersey to make sure that nothing like that ever again emerges from the Garden State.
There are people studying the bases for this phenomenon with an eye toward application in what is now being termed “neural advertising.” So far the data show that it’s not just rhythm or tonality or content. It appears that earworms may be based on a number of rhythmic activities in the brain that when synchronized make it very hard for the sufferer to break the loop. And the day that some advertising house finds the key to making the ultimate earworm that will never let you escape its brand-name looping goodness will be the day that there will probably be mass lynching of ad executives and neural advertisers all around the world. (“There are some things man was not meant to meddle in, my dear Dr. Frankensound.”)
But how much of this talk of “neural advertising” is real? Is there really an industry out there that uses neuroscience and psychology data? And the bigger question is, does it work or is it the buzzword of the week? Yes, it is real, and it can work, but it usually doesn’t, for some pretty basic reasons.
Let’s look at a specific example of what you might try to do with auditory brain hacking and examine how well it might work. Imagine you’re an advertising creative type and you have to sell a romantic product targeted for women. Men’s and women’s brains are different, and they hear differently as well, although spending a lot of time calculating the gender gap in loudness and frequency thresholds probably wouldn’t show enough of a difference to be worth it at a practical level. But if you remember back to an earlier chapter, an awful lot of the auditory system is dedicated to detecting and differentiating between desirable and undesirable mates. Sound-based mate selection by females is not limited to frogs—just look at the demographics for Barry White fans and you will get my drift. A deep, low-pitched voice implies a big source, and in sound as in life, size does matter, especially to the subconscious bits of your mind.
But let’s take it a step further. Size is highly correlated with pitch due to volume and mass of the vibrating surfaces that both make and detect sounds, and for us bipedal types, height is a big consideration in mate selection processes. So the sound designer can use a low-pitched sound or voice and also fool the ears into thinking that the sound is coming from a point higher than the listener.
This is tricky. While the superior olive can localize sound left to right (and front to back to a lesser degree), vertical sound cues are strongly dependent on the shape of your outer ears,
with their little bumps and valleys. The trouble is, everyone’s outer ears are slightly different. (There have even been a few forensic cases in which an ear print was used for identification purposes.) Your brain, having lived with your ears for quite a while, is able to interpret whether things come from above or below based on notches (frequency-limited reductions) and peaks (frequency-limited amplifications) in the sound. Luckily, sound localization, even in the vertical plane, is a well-studied area of auditory psychophysics. There have been a few studies demonstrating that if you create a filter that changes the position of a spectral notch from 6 to 8 kHz in wide-band noise, it will appear as if the sound is moving upward. So our sound designer, being a genius and having way too much software and time on his hands, takes a vocal recording saying the name of this romantic product, pitch-shifts it down to the Barry White zone, and embeds it in quiet sound that has an upward-sweeping high-frequency notch, and suddenly the target audience is hearing the name of the product in a very sexy voice coming from a very tall potential mate. Fire off the signal to a wide selection of sites in the brain, ranging from the auditory cortex to attention areas in the prefrontal cortex and to hypothalamic and preoptic regions controlling things ranging from pupil size to arousal, and voilà—you
may
have attracted the listener’s attention and created a very positive, very sexy deep-seated response to something that was just a name.
If only it were that easy.
Your listener could be a man. Men often react to this kind of manipulated sound with irritation or annoyance. So they aren’t going to buy this product as a gift. A woman may not be interested, even at a deeply wired level, in men. Or perhaps the listener’s ears are such that she gets her vertical position information
in the 8–10 kHz range. Or perhaps a case of Barry White albums fell out a window when she was a child and killed her kitten. Brain hacking will work on a statistically significant portion of the population, but people’s brains are even more individualized than their fingerprints. And statistics are only valid for populations—you can’t predict the success or failure of any given stimulus on any given individual.