For years, brain-imaging technologies have been dedicated to medical pursuits, such as finding brain tumors or pinpointing stroke damage. But practically every other day now you read stories about brain scans being used for less than life-or-death pursuits: scanning the brain activity of people as they watch TV sitcoms or think about soft drinks. On Tuesday, the New York Times ran a front-page story about a study that analyzed the brains of political partisans as they viewed Kerry and Bush campaign ads. If you thought Googling for yourself was the sign of a self-obsessed culture, get ready for the personal brain scan.
Read enough of these stories, and you wonder what would happen if you put your own brain under the scanner. What unique configuration in your cerebral cortex would be revealed under such scrutiny? What telltale pattern of firing neurons would you discover? As it turns out, you don't need to volunteer yourself for a research study to get a glimpse of the inner life of your brain. As part of the research for my latest book, Mind Wide Open,I sampled most of the technologies available today. Some of these tools gaze directly into your brain, while others follow more oblique paths to gauge your state of mind. You can buy some of them for around $100 and have them up and running in five minutes. Others either require you to get an advanced degree, or to befriend someone who already has one. What follows is a consumer guide to getting your head examined, roughly arranged by ease-of-use and accessibility.
Biofeedback. One of the oldest technologies for peering inside your brain involves an indirect route through the body. Biofeedback uses special sensors to track information about your heart rate or the "galvanic skin response" of your fingers and palms. Increases in these levels are a telltale sign of an agitated, amped-up mental state. Lower levels suggest states of deep relaxation and calm. The premise behind biofeedback is not just to track this information, but to make it visible to you in real-time, usually via a computer screen. By seeing this extra layer of feedback, you can learn to recognize and control what are usually unconscious processes. One of the first uses for biofeedback during its initial heyday in the '70s was helping meditators reach more profound states of tranquility.
Search for biofeedback online and you'll find an entire universe of gadgets, most of them marketed by small, New Agey startups with names like Bionetica and Calmlink. Journey to Wild Divine, the most consumer-friendly product in the field, is part biofeedback device and part video game. Wild Divine lets you navigate a Myst-like virtual world, filled with the obligatory tests and puzzles that have to be completed to advance to the next level. The twist is that you don't solve the puzzles by typing on the keyboard or clicking the mouse; you solve them by changing your heart rate or your GSR. The game comes with three sensors that you wear as rings around your fingers and that plug into the USB port on your PC. The more relaxed you get, the better you are at the game.
Pros: A videogame that's good for your soul, and relatively cheap, too.
Cons: Not a direct vista into brain activity; very hard to play on coffee.
What You'll Learn: Wild Divine will likely make you more aware of subtle shifts in your overall sense of calm and potentially help you to seek out states that you find more rewarding.
Cost: $159.95, assuming you've got a computer to play it on.
Neurofeedback. A variation of biofeedback that looks directly at your brain's activity, neurofeedback tracks brain waves that can be detected by an electrode placed on the surface of the skull. At any given moment, millions of neurons in your brain are building up tiny electric charges and then releasing neurotransmitters, which indirectly transmit the voltage to other neurons via their axons. This neuronal communication happens in unison, creating a collective rhythm that generates waves of electrical activity. Researchers have identified a half dozen or so distinct wave states, each associated with a certain mode of consciousness. For example, one called Delta appears in non-REM sleep; Alpha is associated with states of relaxation; Beta often indicates a focused brain; and Theta usually suggests a more scattered frame of mind.
As in biofeedback, the neurofeedback tools project the information about your brain's activity onto some kind of real-time display, which helps you to push your brain into desired states. The inventor Ray Kurzweil has funded research into neurofeedback tools that encourage trancelike Alpha states, while a number of startups and attention experts have explored using neurofeedback to treat ADD. Some athletes and performance gurus trying to get their heads "in the zone" swear by a device called the Peak Achievement Trainer that conceals a band of sensors inside an ordinary-looking visor, allowing you to get brain wave data while touching up your PowerPoint presentation or working on your putting stroke.
Pros: Always-on neurofeedback means you'll never leave "the zone."
Cons: Brain-wave scanning is not as precise an index of neural activity as other types of scans;wearing visor while sitting in your cubicle may attract strange looks.
What You'll Learn: Depends on which waves you're tracking. If you're looking at the attention-related waves of Beta and Theta, you'll learn which situations (talking to people, reading, writing, listening to music) your brain naturally "locks into" and which settings cause it to wander.
Cost: The Peak Achievement Trainer sells for $3,295, though there are much cheaper, albeit less portable, options on the market. This site is a good place to look for lower-priced items as well as general neurofeedback information.
Cortisol tracking. Your mental state is as much a product of the chemicals circulating through your brain (and often through your body) as it is the product of neuronal activity in specific brain areas. Neurochemistry is already part of the popular vernacular: Think of the endorphins that cause the "runner's high" or the serotonin molecule that's central to the effects of Prozac.
Modern medicine (and not-so-modern recreational drugs) let us manipulate our chemical states, but the tools available for tracking our various neurochemical levels are more limited. It's much easier to create a pill that increases the availability of serotonin in the brain than it is to figure out exactly how much serotonin is actually shuffling around in there. Perhaps the closest thing to neurotransmitter analysis available right now involves the stress hormone cortisol. Technically speaking, cortisol is not produced directly in the brain—it originates in the adrenal glands—but its release is triggered by a brain substance called corticotropin-releasing factor or CRF.
Elevated cortisol levels usually accompany severe depression in adults, and suicide victims often turn out to have enlarged adrenal glands, signaling unusually high cortisol production. Because cortisol levels rise and fall with a daily rhythm, some doctors believe that a crucial first step to treating stress and sleep disorders is determining when there are aberrations in the patient's daily pattern of cortisol release. The nice thing about cortisol is that you can track its presence in your system via simple saliva tests. A number of companies sell home cortisol tests, though you have to send the sample back to their labs for results. A doctor or therapist may also be able to do more extensive (and expensive) tests that look at cortisol levels at different points in the day.
Pros: Gives you insight into your brain chemistry; saliva sample makes it easy to take samples at home or the office.
Cons: Cortisol is only one player among many in the chemistry of emotion.
What You'll Learn: If you have stretches in the day where you reliably crash, or can't get enough energy, these tests will show if your natural cortisol rhythms are out of whack.
Cost: A single home test goes for $65.95, but a suite of tests, plus a therapist's fee, will most likely be closer to $500.
Functional Magnetic Resonance Imaging. fMRI is the holy grail of brain imaging. Traditional MRI scans let you see three-dimensional portraits of brain anatomy, but fMRI goes further: It gives you amazingly precise images of which groups of neurons are firing at any given time inside your head—which areas are furiously working and which are slacking off. fMRI machines use powerful magnets and complex mathematical analysis to detect subtle changes in blood flow to specific parts of the brain, ultimately representing brain activity in color-coded images that look something like Doppler weather reports. You'll need an expert to interpret these images, unless you're harboring a grad degree in neuroscience.
Although the experience of having your fMRI images interpreted is truly amazing—the fear centers of your brain light up when you think a disturbing thought, and your language centers kick into gear as you read a sentence—the scanning process itself is extremely uncomfortable. You have to remain completely motionless inside a tiny tube for up to an hour.The machine itself makes an excruciating noise that sounds as if a truck is backing up in your brain.
The hitch with fMRI technology is that you're not likely to install one in the basement: They retail for a couple million dollars. Your best bet is probably to sign up as a test subject at your local university and then plead with the researchers for some special snapshots of your brain to show the folks back home.
The benefits of an fMRI scan depend on the experiment, and the results are closer to clues and hunches than Empirical Scientific Facts. But they can be tantalizing. When I spent time in the scanner, we looked at my brain doing a number of language-related tasks: reading other people's text, reading passages from my own book, and then composing actual sentences. What we found was that the moments where I was the most focused on writing were also the moments where there was the least activity in my brain. (For instance, even though my eyes were open, there was far less activity in the areas that process visual information.)
Seeing these images made me think that hitting states of intense creativity or focus is all about shutting the brain down, rather than revving it up. In the political scans that the New York Times wrote about, the researchers found early evidence that Democrats respond to images of violence (whether in the service of Democratic or Republican candidates) with markedly increased activity in the amygdala, a central player in the brain's emotion and fear circuitry. Republican brains showed little amygdala activity. What that means is very much up for grabs, but it's a fascinating place to start speculating.
Pros: Short of neurosurgery, the closest you'll get to seeing the inside of your brain.
Cons: Claustrophobics need not apply; data difficult to interpret without dozens of other brains to compare yours to.
What You'll Learn: The sky's the limit. It all depends on what you scan your brain doing: thinking of loved ones, watching political ads, dreaming. And you'll need a good guide.
Cost: Free if you're lucky; otherwise, $2 million.