Reviewed by Dennis Drabelle

There's a moment about halfway through The Head Trip that epitomizes its tone: enthusiasm tempered by the realization that for some readers this book may be a ride to Woo-woo Land. Author Jeff Warren is summarizing a psychological study in which "one group practiced tensing and relaxing a finger in their left hands, and another group just imagined doing the same thing." When it was all over, the finger strength of the physical tensers had increased by an average of 30 percent, but that of the mental tensers had gone up nearly as much, to 22 percent. Before going on to point out that visualization can prompt the motor cortex to fire in much the same way that actual exercise does, and that Michael Jordan and other athletes have used the technique to help their game, Warren pauses to react: "Isn't that insane?"

But if you look beyond the book's flower-child title, as well as its numerous drawings and diagrams, you find yourself being instructed by a serious journalist with both feet on the ground -- except when he's in bed and taking part in experiments. In The Head Trip, Warren pursues his conviction that "consciousness exists in more widely varied and abundant forms than simple waking, sleeping, and dreaming" by talking with experts and submitting to protocols. In a Montreal clinic, for example, he gets a handle on hypnagogia -- the stage between light and deep sleep in which wild associations can occur -- by wearing a transmitter on his head and letting his night's rest be videotaped.

The resulting film seems to have been every bit as tedious as Andy Warhol's "Sleep," but Warren's discussion of how savvy artists exploit hypnagogia makes good reading. Salvador Dali used to trawl his brain for bizarre images to go into his surrealist paintings by sitting in a chair after a meal with his hands extended beyond the chair-arms and a key held between the thumb and forefinger of his left hand. When he nodded off, the key would fall to the floor, make a clink, and wake him up so that he could go sketch the melting watch he'd just glimpsed on his inner canvas.

One of Warren's best chapters covers lucid dreaming, in which the sleeper knows he's dreaming (when the images get silly enough, a kind of emcee function in the dreaming self seems to kick in). Here again Warren is burdened with a contraption, the NovaDreamer, a mask worn on the face, with a button to push; if it flashes and chirps, you know you're awake. In the course of the experiment, Warren has an experience that reminds us what a diabolically complex organism the brain is: He pushes the button that will prove he's awake, nothing happens, and he realizes he has dreamed the whole button-pushing sequence. His investigation of lucid dreaming brings him a new understanding of how important the mind (as opposed to the more primitive brain-stem) is to the direction dreams take, and he finds himself agreeing with one theorist's explanation that the weirdness of dreams is "exactly what you would expect if you let the mind run free in a milieu without sensory input to restrain it."

Among Warren's practical suggestions is that "consolidated" sleep -- eight hours straight -- may not be the best way for everybody to get his daily allotment of sawn wood. Tribal people tend to bunk down in communal rooms, and they may mix periods of waking and sleeping throughout the night. The Mediterranean siesta offers another alternative to what sleep scientists call the "Western" pattern, with its insistence on down-you-go-and-don't-stir-till-morning-comes. (Few Westerners will find it convenient to break the eight-solid-hours mold, but that tells you more about the kind of society we are than what our bodies and minds might really need.)

Warren concludes his voyage to the end of the night by formulating what his research has been leading up to: "We can learn to direct our own states of consciousness" -- "we" being not just Buddhist monks and contemplative nuns, but people living workaday lives. It may be a bit early in the game to be so sure of this -- as the author himself notes, sleep research is only about 50 years old -- but by this point Warren has buckled on enough devices, schmoozed with enough experts and provided enough diagrams to make a good case that those italicized words aren't just a pipe dream.

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