Garden of the Mind

The history of science is littered with bones. Since antiquity, humans have studied the remains of the dead to understand the living. The practice is as common now as ever; only the methods have changed. In recent years, high-tech analyses of human remains have solved mysteries ranging from our ancestors’ prehistoric mating patterns to the cause of Beethoven’s death. The latest example of this morbid scientific tradition can be found in the e-pages of this month’s PLOS Pathogens. The colorful cast of characters includes European geneticists, a handful of teeth, a 6^th century plague, and the US Department of Homeland Security.

Although the word plague is often used as a synonym for disease, plague actually refers to a particular type of illness caused by the bacterium Yersinia pestis. Rampant infection by Y. pestis was responsible for a recent pandemic in the 19^th to 20^th centuries. Before that it caused the 14^th to 17^th century pandemic that included the epidemic known as the Black Death.

Yet the pestilence of pestis may have swept across human populations long before the Black Death. According to historical records, a terrible pandemic killed people from Asia to Africa to Europe between the 6^th and 8^th centuries. It struck the Roman Empire under the watch of Emperor Justinian I, who contracted the disease himself but survived. The pandemic now bears his name: the Justinianic Plague. But was Justinian’s malady really a plague or has history pinned the blame on the wrong bacterium? A group of researchers in Munich decided to find out.

How?

By digging up ancient graves, of course. And helping themselves to some teeth.

The ancient graves were in an Early Medieval cemetery called Aschheim in the German state of Bavaria. The site was a strange choice; the authors reveal in their paper that the historical record shows no evidence that the Justinianic Plague reached Bavaria. However, the site was conveniently located within driving distance of most of the study’s authors. (It’s always easiest to do your gravedigging closer to home.) The authors did have solid evidence that the graves were from the 6^th century and that each grave contained two or more bodies (a common burial practice during deadly epidemics). In total, the group dug up 12 graves and collected teeth from 19 bodies.

The scientists took the teeth back to their labs and tested them for a stretch of DNA unique to Y. pestis. Their logic: if the individuals died from infection by Y. pestis, their remains should contain ample DNA from the bacteria. Of course, some of this DNA would have deteriorated over the course of 1.5 millennia. The scientists would have to make do with what they found. They used three different methods to amplify and detect the bacterial DNA, however they only found a reliably large amount of it in the teeth of one individual, a body they affectionately nicknamed A120. They genotyped the Y. pestis DNA found in A120 to see how the bacterial strain compared with other versions of the bacterium (including those that caused the Black Death and the 19^th-20^th century plague pandemic.) The analysis showed that the Justinianic strain was an evolutionary precursor to the strain that caused the Black Death. Like the strains that sparked the second and third pandemics, this strain bore the genetic hallmarks of Y. pestis from Asia, suggesting that all three plague pandemics spread from the East.

The authors write that they have solved their historical mystery.

“These findings confirm that Y. pestis was the causative agent of the Justinianic Plague and should end the controversy over the etiological agent of the first plague pandemic.”

Ordinarily, the discussion sections of scientific papers are littered with qualifiers and terms like might be and suggestive. Not so here, even though the authors’ conclusion explains a phenomenon that killed many millions of people worldwide based on data from the decomposing remains of a single person who lived in a region that historians haven’t connected with the pandemic. In most branches of science, sweeping conclusions can only be made based on large and meticulously selected samples. In genetics, such rules can be swept aside. It is its own kind of magic. If you know how to read the code of life, you can peer into the distant past and divine real answers based on a handful of ancient teeth.

As it turns out, the study’s result is more than a cool addition to our knowledge of the Early Middle Ages. Plague would make a terrible weapon in the hands of a modern bioterrorist. That’s why the US Department of Homeland Security is listed as one of the funding sources for this study. So the next time you hear about your tax dollars hard at work, think of Bavarian graves, ancient teeth, and poor old A120. And be grateful.

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Photo credit: Dallas Krentzel

Today we’re talking bodies. Not how they look in skinny jeans or whether they can win a Tour de France without steroids. We’re talking about how it feels to have a body of your own, one that is (or seems to be) conveniently connected to your head and neck.

I’ve written about body ownership before in the context of pregnancy. Although I focused on how I dreamt of my body during sleep, I also mentioned that my ballooning physical dimensions affected my coordination. I’d bump into countertops or doorways with my big belly and sometimes struggled to locate my center of gravity. Yet as strange as my new body was, it always felt like it belonged to me. This was an enormous blessing, of course, but it’s somewhat surprising  as well. After all, before my pregnancy I’d lived with the same body since puberty. After more than a decade and a half of experience with that body, I suddenly had to adjust to my new body in a matter of months. Or rather days, because that new body kept growing larger still. Although my belly would feel surreal at times, overall I had remarkably little trouble adjusting to my metamorphosis. The body was still mine in all its lumpy glory.

I was reminded of this experience recently when I came across a scientific paper about body swapping. I know it sounds as if the only science in something called body swapping must come from the term science fiction. Actually, body swapping is a remarkable perceptual illusion that requires nothing more than a second person, a set of head mounted cameras and a set of head mounted displays. Someone facing you wears the cameras mounted on a helmet and you wear the visual displays (which are presented to your two eyes like goggles as part of a virtual reality-style headset). The camera footage, filmed from the visual perspective of the second person, is fed directly into your visual display. Thus, you see your own body from the second person’s perspective.

But we haven’t made it to Freaky Friday just yet. The illusion requires something more. You and the other person take each other’s hands and begin squeezing them simultaneously. Nothing fancy. But in the words of the write up by Valeria Petkova and Henrik Ehrsson, this simple setup alone “. . . evoked a vivid illusion that the experimenter’s arm was the participant’s own arm and that the participants could sense their entire body just behind this arm. Most remarkably, the participants’ sensations of the tactile and muscular stimulation elicited by the squeezing of the hands seemed to originate from the experimenter’s hand, and not from their own clearly visible hand.”

So after a lifetime in your own body, it only takes a video feed and a few hand squeezes for you to make yourself at home in someone else’s arms and legs. If this setup sounds familiar, it is a more impressive incarnation of the classic rubber hand illusion. And a new and remarkable twist on the illusion just appeared in the news: scientists in the same lab have made people feel as if they have an invisible hand. (For a great discussion of this new illusion, read this.)

In science, we tend to think about human perception in general and illusions in particular in terms of adaptations and optimizations. Lots of visual illusions are based on the statistical probability of objects and events in our environment. Our brains learn to predict and extrapolate information about our settings because they jump to the likeliest conclusions. In this way illusions, while technically errors, often reveal clever shortcuts our brain takes to help us understand or parse our surroundings faster, better, or at less of an energy cost.

But what about the body swap? Since we never actually swap bodies, why should we mentally be able to do it? What’s the advantage? Well, the advantage seems to come down to the very fact that we never actually swap bodies. In our ever-changing world, a rare given is that you will have the same body tomorrow that you had today and yesterday. So why should your brain waste precious time or energy soliciting proof from every finger and toe, curve and joint, flex and bend? Take a smidge of visual evidence (in this case, the video display) and a dab of tactile confirmation (hand squeezing) and you have a recipe for body ownership. How often in the natural world would this recipe ever lead you astray?

So in essence you only think that you feel that you own your body. In truth, your brain is creating that sensation on the fly all the time. You could think of it as a philosophical conundrum or cause for an existential crisis. I prefer to think of it as good news for pregnant ladies everywhere.

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Photo credit: Elizabeth Tan

I’ve got lead on my mind. Lead the element, not the verb; the toxic metal that used to grace every gas tank and paint can in this grand country of ours. For the most part we’ve stopped spewing lead into our environment, but the lead of prior generations doesn’t go away. It lingers on the walls and windows of older buildings, on floors as dust, and in the soil. These days it lingers in my thoughts as well.

I started worrying about lead when my daughter became a toddler and began putting everything in her mouth. I fretted more when I learned that lead is far more damaging to young children than was previously thought. Even a tiny amount of it can irreversibly harm a child’s developing brain, leading to lower IQs, attention problems and behavioral disorders. You may never even see the culprit; lead can sit around as microscopic dust, waiting to be inhaled or sucked off of an infant’s fingers.

Public health programs use blood lead levels (BLLs) to evaluate the amount of lead in a child’s system and decide whether to take preventative or medical action. In the 1960s, only BLLs above 60 μg/dL were considered toxic in children. That number has been creeping downward ever since. In 1985 the CDC’s stated blood lead level of concern became 25 μg/dL and in 1991 it went down to 10. But last year the CDC moved the cutoff down to 5 μg/dL and got rid of the term “level of concern.” That’s because scientists now believe that any amount of lead is toxic. In fact, it seems as if lead’s neurotoxic effects are most potent at BLLs below 5 μg/dL. In other words, a disproportionately large amount of the brain damage occurs at the lowest doses. Recent studies have shown subtle intellectual impairments in kids with BLLs as low as 2 μg/dL (which is roughly the mean BLL of American preschoolers today). All great reasons for parents to worry about even tiny exposures to lead, no?

Yes. Absolutely. Parents never want to handicap their children, even if only by an IQ point or two. But here’s what’s crazy: nearly every American in their fifties, forties, or late-thirties today would have clocked in well over the current CDC’s cutoff when they were little. The average BLL of American preschoolers in the late ‘70s was 15 μg/dL – and 88% had BLLs greater than 10 μg/dL.

These stats made me wonder if whole generations of Americans are cognitively and behaviorally impaired from lead poisoning as children. Have we been blaming our intellectually underwhelming workforce on a mismanaged education system, cultural complacency, or the rise of television and video games when we should have been blaming a toxic metal element?

I was sure I wasn’t the first person to wonder about the upshot of poisoning generations of Americans. And lo and behold, a quick Google search led me to this brilliant article on Mother Jones from January. The piece chronicles a rise in urban crime that began in the ‘60s and fell off precipitously in the early-to-mid ‘90s nationwide. The author, Kevin Drum, walks readers through very real evidence that lead fumes from leaded gasoline were a major cause of the rise in crime (and that increased regulation restricting lead in gasoline could be credited for the sudden drop off.)

The idea certainly sounds far-fetched: generations of city-dwellers were more prone to violence as adults because they breathed high levels of lead fumes when they were kids. It doesn’t seem possible. But when you put the pieces together it’s hard to imagine any other outcome. We know that children of the ‘50s, ‘60s, and ‘70s had BLLs high enough to cause irreversible IQ deficits and behavioral problems (of which aggression and impulse control are particularly common). Why is it so hard to imagine that more of these children behaved violently when they became adults?

In the end, this terrible human experiment in mass poisoning has left me pondering two particular questions. First, what does it mean for generations of children to be, in a sense, retroactively damaged by lead? At the time, our levels were considered harmless, but now we know better. Does knowing now, at this point, explain anything about recent history and current events? Does it explain the remarkable intransigence of certain politicians or the bellicosity of certain talk show hosts, athletes, or drivers with a road rage problem? Aside from the crime wave, what other sweeping societal trends might be credited to the poisoning of children past? How might history have played out differently if we had all been in our right minds?

Finally, I’ve been thinking a lot about the leads and asbestoses and thalidomides of today. Pesticides? Bisphenol A? Flame retardants? What is my daughter licking off of those toys of hers and how is it going to harm her twenty years down the line? This is not just a question for parents. Think crime waves. Think lost productivity and innovation. Today’s children grow up to be tomorrow’s adults. Someday when we are old and convalescing they’ll take the reigns of our society and drive it heaven-knows-where. That makes child health and safety an issue for us all. We may never even know how much we stand to lose.

You might call it a Frankenstein genre – two quite different literary genres stitched together and brought to life. For the moment, I am calling it the scimoir. The rare science memoir can be found tucked away in the Science section, in Memoir or Biography, even sometimes in Health, Psychology, or Self Help. It defies categorization, flummoxing librarians and booksellers alike. Science and memoir, memoir and science. It just doesn’t seem right.

At first glance the two genres seem incompatible. Science is the study of the immutable and absolute while memoir is the most personal and subjective of all genres. Yet somehow they can go together, and when done well, they resonate with honesty and relevance. They tame each other. Memoir reminds us that the whirring mechanics of science play out on the scale of our individual lives, while science reminds us that the memoirists’ struggles and stories reflect something of the universal. Moreover, the drama of memoir adds the narrative kick that science writing so desperately needs. It’s a match made in genre heaven.

Why am I waxing poetic about a literary genre? I suppose because I recently discovered that I’m drawn to this combination, both as a blogger and as a reader. The majority of my posts are amalgamations of personal experience and scientific theory. This was never my intent; somehow the combination fell out of my interests and whatever spark motivated me to write about a given topic. I’ve also discovered that I’ve read and enjoyed a number of scimoirs, even though I didn’t consciously seek them out and scimoirs are none too common.

In point of fact, I shouldn’t be surprised that book-length scimoirs are relatively rare. To write a compelling one, an author generally has to be a scientist or science writer who has also personally experienced something dramatic that is relevant to the topic. You might be both a leading researcher and lifelong sufferer of a particular illness, like Kay Redfield Jamison in An Unquiet Mind. You might be the researcher behind an infamous experiment, like Philip Zimbardo in The Lucifer Effect. Or you might be able to approach the topic through your experience with ailing relatives. In Mapping Fate, Alice Wexler wrote about her mother’s battle with Huntington’s disease and her sister’s scientific quest to isolate the culprit gene. In Acquainted with the Night, the science writer Paul Raeburn documented his children’s struggles with mental illness in the context of the current state of juvenile psychiatric knowledge and treatment.

I am on a quest to identify other books in this wonderful Franken-genre and I need your help. Here are the other scimoirs I can think of that I’ve already read (aside from those listed above): My Stroke of Insight by Jill Bolte Taylor, The Double Helix by James Watson, A Primate’s Memoir by Robert Sapolsky, and several of Oliver Sacks’s books. I’ve come across a few more that I plan to read: Memoirs of an Addicted Brain by Marc Lewis, Moonwalking with Einstein by Joshua Foer, and What Mad Pursuit by Francis Crick.

Please let me know what other scimoirs you’ve read, want to read, or simply know are out there. And do share any other ideas for naming the genre. Scimoir sounds like a half-android, half-alien monster, and who wants to cuddle up with that?

I just read a wonderful little article about how we think about ourselves. The paper, which came out in January, opens with a tantalizing paragraph that I simply have to share:

“At every stage of life, people make decisions that profoundly influence the lives of the people they will become—and when they finally become those people, they aren’t always thrilled about it. Young adults pay to remove the tattoos that teenagers paid to get, middle-aged adults rush to divorce the people whom young adults rushed to marry, and older adults visit health spas to lose what middle-aged adults visited restaurants to gain. Why do people so often make decisions that their future selves regret?”

To answer this question, the study’s authors recruited nearly 20,000 participants from the website of “a popular television show.” (I personally think they should have told us which one. I’d imagine there are differences between the people who flock to the websites for Oprah, The Nightly News, or, say, Jersey Shore.)

The study subjects ranged in age from 18 to 68 years of age. For the experiment, they had to fill out an online questionnaire about their current personality, core values, or personal preferences (such as favorite food). Half of the subjects—those in the reporter group—were then asked to report how they would have filled out the questionnaire ten years prior, while the other half—those in the predictor group—were asked to predict how they will fill it out ten years hence. For each subject, the authors computed the difference between the subject’s responses for his current self and those for his reported past self or predicted future self. And here’s the clever part: they could compare participants across ages. For example, they could compare how an 18-year-old’s prediction of his 28-year-old future self differed from a 28-year-old’s report of his 18-year-old self. It sounds crazy, but they did some great follow up studies to make sure the comparison was valid.

The results show a remarkable pattern. People believe that they have changed considerably in the past, even while they expect to change little in the future. And while they tend to be pretty accurate in their assessment of how much they’ve changed in years passed, they are grossly underestimating how much they will change in the coming years. The authors call this effect The End of History Illusion. And it’s not just found in shortsighted teenagers or twenty-somethings. While the study showed that older people do change less than younger people, they still underestimate how much they will continue to change in the decade to come.

The End of History Illusion is interesting in its own right. Why are we so illogical when reasoning about ourselves – and particularly, our own minds? We all understand that we will change physically as we age, both in how well our bodies function and how they look to others. Yet we deny the continued evolution (or devolution) of our traits, values, and preferences. We live each day as though we have finally achieved our ultimate selves. It is, in some ways, a depressing outlook. As much as we may like ourselves now, wouldn’t it be more heartening to believe that we will keep growing and improving as human beings?

The End of History Illusion also comes with a cost. We are constantly making flawed decisions for our future selves. As the paper’s opening paragraph illustrated, we take actions today under the assumption that our future desires and needs won’t change. In a follow up study, the authors even demonstrate this effect by showing that people would be willing to pay an average of $129 now to see a concert by their favorite band in ten years, while they would only be willing to pay an average of $80 now to see a concert by their favorite band from ten years back. Here, the illusion will only cost us money. In real life, it could cost us our health, our families, our future well-being.

This study reminded me of a book I read a while back called Stumbling on Happiness (written, it turns out, by the second author on this paper). The book’s central thesis is that we are bad at predicting what will make us happy and the whole thing is written in the delightful style of this paper’s opening paragraph. For those of you with the time, it’s worth a read. For those of you without time, I can only hope you’ll have more time in the future. With any luck we’ll all have more – more insight, more compassion, more happiness—in the decade to come.

Photo by Novartis AG on Flickr

In my last post, I wrote about whether we can imagine experiencing a sense that we don’t possess (such as a trout’s sense of magnetic fields). Since then a study has come out that adds a new twist to our little thought experiment. And for that we can thank six trailblazing rats in North Carolina.

Like us, rats see only a sliver of the full electromagnetic spectrum. They can perceive red light with wavelengths as long as about 650 nanometers, but radiation with longer wavelengths (known as infrared, or IR, radiation) is invisible to them. Or it was before a group of researchers at Duke began their experiment. They first trained the rats to indicate with a nose poke where they saw a visible light turned on. Then the researchers mounted an IR detector to each rat’s head and surgically implanted tiny electrodes into the part of its brain that processes tactile sensations from its whiskers.

After these sci-fi surgeries, each rat was trained to do the same light detection task again – only this time it had to detect infrared instead of visible light. Whenever the IR detectors on the animal’s head picked up IR radiation, the electrodes stimulated the tactile whisker-responsive area of its brain. So while the rat’s eyes could not detect the IR lights, a part of its brain was still receiving information about them.

Could they do the new task? Not very well at first. But within a month, these adult rats learned to do the IR detection task quite well. They even developed new strategies to accomplish their new task; as these videos show, they learned to sweep their heads back and forth to detect and localize the infrared sources.

Overall, this study shows us that the adult brain is capable of acquiring a new or expanded sense. But it doesn’t tell us how the rats experienced this new sense. Two details from the study suggest that the rats experienced IR radiation as a tactile sensation. First, the post-surgical rats scratched at their faces when first exposed to IR radiation, just as they might if they initially interpreted the IR-related brain activity as something brushing against their whiskers. Second, when the scientists studied the activity of the touch neurons receiving IR-linked stimulation after extensive IR training, they found that the majority responded to both touch and infrared light. At least to some degree, the senses of touch and of infrared vision were integrated within the individual neurons themselves.

In my last post, I found that I was only able to imagine magnetosensation by analogy to my sense of touch. Using some fancy technology, the scientists at Duke were able to turn this exercise in imagination into a reality. The rats were truly able to experience a new sense by piggybacking on an existing sense. The findings demonstrate the remarkable plasticity of the adult brain – a comforting thought as we all barrel toward our later years – but they also provide us with a glimpse of future possibilities. Someday we might be able to follow up on our thought experiment with an actual experiment. With a little brain surgery, we may someday be able to ‘see’ infrared or ultraviolet light. Or we might just hook ourselves up to a magnificent compass and have a taste (or feel or smell or sight or sound) of magnetosensation after all.

Most of the time I forget that my mother lacks a sense of smell. It’s only when I complain about something stinky or comment on a delicious smell that I remember she isn’t sharing the experience with me. As I’ve mentioned before, my mother has never had a sense of smell, or at least none that she can ever remember. As a child, I often wondered how she might imagine the sensation of smell. Would she do it by analogy to her other senses? Would she be able to do it at all?

I returned to these musings from a different perspective recently when I read a scientific paper about trout. Trout, along with other migratory species from salmon to sea turtles and certain types of birds, enjoy a sense that we lack: magnetosensation. These animals perceive magnetic fields (including that of the Earth) and can use this information to orient themselves and navigate. The study’s authors found magnetic cells inside the noses of trout, each with tiny iron-containing crystals attached to their cell membranes. Thus, when a trout changed direction relative to the Earth’s magnetic field, these miniature magnets would presumably tug on the cell’s membrane in a way that the cell could detect and signal to other parts of the trout’s nervous system. The evolution of these wonderful little biological compasses may have been necessary for migrating animals to evolve on our planet and happily roam, return, and repeat.

So today I put myself in my mother’s shoes (or nose) and tried to imagine a sense I didn’t have. What would it be like to feel magnetic fields? I tried to embrace the role and be the trout. I closed my eyes and imagined my little trout self swimming around within a magnetic field that changed as I moved. How would that feel for the trout? My imaginative efforts were rewarded with a strong percept – flashes of tingling across the surface of my skin that mirrored my changes in direction. In essence, I could only imagine magnetosensation by analogy to somatosensation, the sense of touch. And this is almost certainly not what magnetosensation feels like to a trout. Not only do they already have a sense of touch akin to our own, but they also detect magnetic fields with their snout rather than their whole body.

It makes sense that I imagined a foreign sensation by analogy to one I know. Each of our senses has dedicated processing areas in the brain. Without a brain area developed for magnetosensation, it may not be possible to do any better than imagine it by way of the senses our brain can process. Or maybe it’s possible for people with more imaginative imaginations than my own. If you give it a try, please let me know what you come up with! And the next time you find yourself staring down a trout, tilapia, tuna, or salmon on your plate, spare a moment to appreciate that it has experienced a realm of sensations beyond your imagination. And then – bon appétit!

Now that my daughter is about to reach her first birthday, I’m in the mood to reflect on the year that just passed. Unfortunately, my recollections of it are a little fuzzy, probably because I can count on one hand the number of times I’ve enjoyed a good night’s sleep over the past year. Some people have babies who regularly sleep through the night and I am happy for them. Truly, I am. But clearly I was not meant to be in their ranks.

Still, the never-ending parade of nighttime awakenings has taught me something about my own brain. It is precisely tuned to hear my baby. Although I sleep blithely through my husband’s thunderous snoring and the loud buzz of his alarm clock – multiple times a day, thanks to the snooze button – I awaken at the faintest sound of my daughter’s sighs, coos, or grumbles. When she cries, I am immediately awake while my husband sleeps on beside me, undisturbed.

People are generally able to sleep through minor sounds and sensations thanks to a subcortical structure in the brain called the thalamus. This structure receives incoming signals from our senses and relays them to cortical areas devoted to processing sensory information like sounds or tactile sensations. When we’re awake, the thalamus faithfully relays nearly every sensory signal on to the cortex. But when we’re asleep, neurons in the thalamus participate in strong, synchronized waves of activity that squelch incoming signals. As a result, about 70% of these signals never make it to the cortex. This process, known as sensory-gating, is how we manage to sleep through the roar of rainstorms or the brush of the sheets against our skin each time we turn in bed. It is also how we sleep through our husband’s room-rattling snores.

Yet some sensory information does get through to the rest of the brain during sleep. These signals do get processed and can even wake us up if they are either intense (like a loud noise) or personally relevant. A clever study illustrated the importance of personal relevance by exposing sleeping subjects to a loud presentation (via tape recorder) of their own name spoken aloud. The scientists played the recording either normally or backwards and found that subjects awoke in less than half the time when they heard their names presented in the recognizable form.

So did my daughter, in effect, sleep train me by training my brain to recognize her sounds as personally relevant? It’s a plausible explanation, but one that is ultimately lacking. It cannot explain that first night when I slept beside my baby at the hospital nearly one year ago. Although I had labored through the entire night before and had not slept in the ensuing day, I awoke constantly to every little sound my mewing newborn made, not to mention the cries that told me she wanted to nurse. She’d had no time to train me; I had come pre-trained. Just as my breasts were primed to make milk for her, my brain was primed to wake for her. We seemed to be engineered for one other, mother and child, body and brain. And we spent that first long night discovering how clever a designer Nature can be, while my husband slept peacefully on the couch.

As Tuesday’s election approaches and news coverage of super storm Sandy recedes, I’m struck by the absurdity of our current situation. While cities on the East Coast are still pumping water out of tunnels and salvaging belongings from ruined homes, we get back to talking about the economy. That and reproductive rights.

Yet we are surrounded by evidence of climate change, even beyond our recent run-ins with Sandy and Irene. We have seen increases in the frequency and severity of storms, droughts, and wildfires. Already, drought has affected food prices here in the U.S. and caused widespread famine in Africa. Massive ice shelves in Antarctica are melting and crumbling into the sea, demonstrably raising sea levels worldwide. And this past year brought us record-breaking temperatures, one after another, as we watched a freakishly warm winter give way to a sweltering summer.

Despite the mountain of scientific evidence that climate change is real and ample demonstrations of the devastation it can wreak, the topic has not been an issue in this year’s presidential election. It wasn’t discussed in any of the three presidential debates. This is not an oversight on the part of the candidates and the moderators. Americans are simply not worried about climate change. In a Gallup poll from September, only 2% of respondents ranked environmental issues as the most important problem facing our country today. Most ranked unemployment and our lagging economy as the nation’s greatest woe.

While people are certainly suffering in today’s economy, the dismissal of climate change is terribly shortsighted. Climate change is an economic threat. It has already raised (and will probably continue to raise) the cost of food. We have also faced steep costs as a result of extreme weather. New York State’s economy alone lost as much as 18 billion dollars due to Sandy and fortifying New York from future flooding could cost upwards of 20 billion dollars. Those figures don’t include the damage in other states and they don’t include the expense to homeowners who are rebuilding or who will try to insure their homes in the wake of this storm. And of course it can’t include the personal devastation and loss of life.

So why aren’t we talking more about climate change? And why aren’t we doing more, both in our own lives and in our voting choices, to try to stem the tide?

It seems to me that we are witnessing a human psychology experiment on the grandest scale. How can we ignore (and in fact perpetuate) an impending disaster of such magnitude? In fact, humans have quite a bit of practice at ignoring future doom. After all, we live out our lives with the certainty that we will die and we function in large part by not thinking about it. Death? What death? Climate change? What change?

I wrote before about how our disappearing glaciers may be suffering from a PR problem. They need a spokesman or a mascot – something that might tug at our heartstrings and make people care. Now I think we need a similar approach for climate change itself. The climatologists have done their job and demonstrated that climate change is real. But our first and greatest obstacle in fixing it may lie within ourselves or, more specifically, our skulls.

I think it’s time to call in the psychologists, the marketing specialists and the public relations gurus. Through years of research, we already know the many ways that human beings are illogical and we know how to persuade and manipulate them. Beer has bikini-clad women. Cigarettes have cowboys. Viagra and Cialis have politicians and quarterbacks. Why can’t we do the same for our planet? It’s time we held focus groups and raised ad dollars. It’s time for a climate campaign.

Popular opinion has always driven political will. We need to use every resource we have to raise awareness and change minds. So let’s bring in the psychologists. Let’s bring in the bikini-clad women if need be. (After all, it’s going to be hot!) But before we can influence others, we have to begin by changing ourselves. By changing our lifestyles. By changing our priorities. By changing our minds and then voting our minds. And there’s no better time to start than this Tuesday.

I’ll see you at the ballot box!

There was a time when my daughter used her hands exclusively to shovel things into her mouth. Not so anymore. For the last few months, she has been hard at work banging objects together. This simple action is setting the stage for some pretty cool neural development. She is learning to use tools.

Of course it doesn’t look too impressive right now. She might bang a ball with a block and then switch and strike the block with the ball. In one recent playtime she tore a cardboard flap out of her board book and examined it, trying different grips and holding it from different angles as she watched how it cut the air. Then, brandishing her precious flap, she went to work. She wielded it with a scooping motion to lift other flaps in the book, and later, to turn the book pages themselves. After that, she descended on her toy box with the flap. She used it to wipe her blanket, poke her stuffed animal, and finally scrape its face like she was giving it a close shave.

Although my daughter’s fun with flaps may seem aimless, it had an important purpose. Through experimentation and observation, she was learning how two objects can interact and how such interactions are affected by object shape, configuration, and pliability. Such details are so well known to adults that we forget there was anything to learn. But consider how often we use objects against one another. We hammer nails, rake leaves, and staple pages. When using scissors, we must apply different levels of force to cut through paper versus cardboard or fabric. When lifting a pan with a potholder, we must adjust our grip depending on the weight of the pan and whether we are lifting it by the base, side, or handle. We must know the subtle differences between holding a sponge to wash a glass and using a towel to dry it, and we must do each deftly enough that our glassware comes out clean and intact at the end.

There are also countless tools we create on the fly every day. When you use a magazine to nudge your cell phone within reach or flip a light switch with a book because your hands are full, you are devising novel tools to fit your momentary needs. To do this, our brains must store extensive knowledge about the properties of household objects. Through experimentation, like the kind my daughter is doing, we learned to predict how objects will interact and to capitalize on those predictions.

So far I’ve described the value of tools in terms of what they can do: push, pull, gather, polish, lift, etc. But there is another side to tool use that may play a role in my daughter’s little experiments: sensory information gleaned through the tool. As I watched her probe one object with another, I was reminded of research described in Sandra and Matthew Blakeslee’s book The Body Has a Mind of Its Own. The book discussed neurons in the parietal cortex that are tuned to the sight or feel of objects near a particular body part. For example, cells representing your right hand would fire if something touched your right hand, if you saw an object near your right hand, or both. Neuroscientists have discovered that experience using a tool can change the properties of these cells in monkeys (and therefore likely in us as well). They found that if monkeys used a rake to gather goodies otherwise beyond their reach, the parietal neurons that had responded to objects around the hand now fired for items located anywhere along both the hand and the rake it held. In a sense, object manipulation can temporarily extend certain neural body representations to include the tools we wield. The Blakeslees suggest that this may be how a blind person learns to perceive the contour of items encountered at the tip of his cane. In effect, the cane and the hand are one.

For now, our house is filled with smashing, scraping, banging and bending as our baby descends on toys and her parents’ belongings alike. In the midst of such havoc, it’s good to know that the destruction is part of a crucial learning process. And someday, once it slows down, I can buy her a new board book with all the flaps intact.