Rainy Brain, Sunny Brain

How to Retrain Your Brain to Overcome Pessimism and Achieve a More Positive Outlook

By Elaine Fox Basic Books. 272 pp. $26.99 Reviewed by Helen W. Mallon

Evidence suggests that the entity formerly known as the "soul" was handed down in a package from our ancestors. If you think these discoveries portend better things for humankind, I'd call you an optimist.

If the notion that well-being is determined by genetics seems grimly deterministic, you might just be afraid that your own gene pool is half-empty.

What does psychologist Elaine Fox, much-hailed discoverer of the "optimism gene," have to say? As Fox describes in Rainy Brain, Sunny Brain, "Getting your head around conundrums … is one of the great joys as well as one of the … frustrations of science." Ergo, having a sunny disposition isn't as simple as nature or nurture.

Despite the title, this is not a self-help book. We are not, Fox argues, doomed to follow the lead of our "rainy brain," which, once upon an ancient time, enabled us to zero in on threats. The brain is adaptable, malleable, and trainable, and if we work at it, we can produce better-adapted, healthier people and communities.

Fox explains that her work on the serotonin transporter gene (LL) was "incorrectly" hailed as the discovery of a happiness bullet. For example, after tissue was sampled from Michael J. Fox, actor, Parkinson's patient, and LL-blessed optimist, it turned out the actor's happy genotype has a catch: His LaLg makeup is more likely a "plasticity" gene that makes him "highly sensitive to his environment, both rewards and threats." Without a grandmother who "saved [Fox] from a family that didn't really 'get him,' " Back to the Future might have starred — Keanu Reeves?

The fear cycle certainly had and has its uses. When a lion stalked one of our ancestors, the fear-oriented brain fired signals to the brain's vision centers, sharpening the eyesight. But when projected into the present, the fear system changes in meaning, taking on huge social and political implications:

Brain scanning experiments have shown that when we are asked to evaluate others, the fear system gets more involved when the faces are from another racial group … those who showed a bigger fear response, as measured by amygdala reaction to out-group faces, also had more racist attitudes.

But the point is that, while genetics may be destiny, there's a lot of room for our input. Happily, Fox cites mounting evidence that throughout life, the brain is highly "plastic." Scientists now increasingly believe that the adult brain is capable of being "sculpted":

The evidence for neural plasticity, even as adults, is growing. This … raises the possibility that major new treatments might be developed for … disorders such as Parkinson's and Alzheimer's disease.

"My own hunch," Fox states, "is that mental health problems … might also be helped by the power of plasticity."

Witness the astonishing flexibility of the blind, who show "strong activity in … areas of the brain [normally] dedicated to vision," when their heightened sense of hearing is engaged. Fox describes a study among cancer patients that discovered "the adult brain can generate new brain cells" at least into one's 70s.

When treatment of phobias succeeds, science tells us why. Conventional "exposure therapy" would expose us to the things we fear — let's say, spiders. It's often combined with the antibiotic cycloserine (which influences the amygdala, "the heart of our fear brain").

But this therapy doesn't just make people less afraid of spiders. It prompts a "sequence of changes initiated throughout the brain that creates a semipermanent trace." The implications for severe conditions such as post-traumatic stress disorder are obvious and exciting. Fear researchers have found that memories are reactivated when they are recalled, leaving them in a temporarily vulnerable state in which new information can be added to the original memory … [this] opens a window of opportunity in which the memory can be altered.

Intriguingly, even our DNA is malleable: "The surprise is that [genetic] changes can be passed on to the next generation without affecting the DNA sequence itself." Fox cites groundbreaking studies in the new field of epigenetics. Analysis of Swedish records showed that alternating winters of starvation and overeating among boys in a remote area "set off a chain of biological events … down the generations so that (all other longevity factors being taken into account) one's grandchildren would die years sooner than their peers."

The brains we inherit continually adapt and change. For those of us who wake up worried, the prognosis is sunny. Fox explains the neurological reasons for the effectiveness of talk therapy, meditation, and pharmacology, but she offers no recipes for happiness. Rather, she criticizes the shallowness of "positive thinking" approaches to self-help.

It's worth sticking with the hard science of Rainy Brain, Sunny Brain. Fox offers persuasive arguments that "we are well on the way toward creating people and societies that will allow healthy minds to truly flourish."