Research on the male brain is never flattering to men.

It always turns out that we're violence-prone, sex-obsessed mammals barely one step more civilized than a vole.

Wait: Make that the male montane vole.

He's a little rascal whose promiscuous behavior might just exceed that of many humans, even NBA players.

On the other hand, his cousin, the male prairie vole, is monogamous for life - a distinction that many human males neither achieve nor aspire after.

I learned about boys and voles in The Male Brain, a new book that might shed some light on Tiger Woods, Jesse James (the celebrity husband and the outlaw) and the profitability of pornography.

The author - Louann Brizendine, a professor of psychiatry at the University of California, San Francisco - didn't set out to dismay me but managed to do so anyway.

I was hoping, for once, that research would show that the connection between the brain and a certain region to the south is much overstated.

But I got no further than Page 4 before I read that "Men have 2 times the brain space devoted to sexual drive in their hypothalamus" than women do.

We're wired that way from birth. The only thing that keeps us from hitting on hot chicks in preschool is the "juvenile pause," the period from ages 1 to 10 when we pass on girls in favor of wrestling, burping and playing with matches.

Why? Testosterone - the "Hey, baby, can I buy you a drink?" hormone - takes a back seat to the Mullerian inhibiting substance, which is thought to make us enjoy exploring, roughhousing and turning Barbies into swords.

Then comes the testosterone spike at puberty.

Brizendine's meditations on the teen-boy brain are dismal. I think I can sum up her treatise in three words: bored, hostile and horny.

Testosterone makes males status-conscious, competitive and ready either to fight or to bluster convincingly, Brizendine says. As for sexual preoccupation, she compares it to both an autopilot and a big-screen television in a sports bar: "always on in the background."

At times, the information gets almost comical: She claims that teen boys can't even hear right, they're so addled by hormones.

"When Zoe (a teen girl) talked endlessly about movies, fashion and other girls," the author writes, "their combined voices just sounded like humming and buzzing to Jake's (a teen boy's) ears."

Oh, please: In my experience, teen boys hear perfectly well, if a bit selectively.

Voles, lizards and marmosets are enlisted to help explain us.

The male montane vole lacks the receptors for vasopressin (the monogamy hormone) that prairie voles have. Brizendine raises the possibility that the same condition explains serial philanderers.

At the very least, it should enable them to fall back on the vasopressin defense when caught.

Maybe research will, as Brizendine hopes, help the sexes understand each other. Or maybe it will just result in the updating of an old excuse: Male brains will be male brains.