No surprise that we live in a world full of junk science, unhelpful self-help, and freakish social sciences—which makes culling the valuable from the vapid somewhat perilous. Not that my approval in these areas is should be construed as a warranty of validity. Fortunately, Dr. Louann Brizendine, whose credentials are impeccable, has already been vetted via her pioneering examination and analysis in The Female Brain.

Having founded the first American clinic devoted to the investigation of biological gender differences, the good doctor has turned her research and scholarship to the other half of the human equation in The Male Brain (Broadway Books).

Here are some of the insights (courtesy of her publisher) Brizendine offers about the male brain:

It is a lean, mean, problem-solving machine. Faced with a personal problem, a man will use his analytical brain structures, not his emotional ones, to find a solution.

It thrives under competition, instinctively plays rough, and is obsessed with rank and hierarchy.

It’s about the size of a cantaloupe. It’s 9 to 10 percent larger than the female brain and has an area for sexual pursuit that is 2.5 times larger than the female brain, consuming him with sexual fantasies about female body parts.

And it experiences such a massive increase in testosterone at puberty that he perceives others’ faces to be more aggressive.

Ambiently, Dr. Brizendine offers this tidbit:

All brains start out with female-type brain circuits until eight weeks of fetal life, when the tiny testicles start to pump out adult-male levels of testosterone that travel in the bloodstream up to the brain. You have to grow all of the basic sex-specific circuitry in the male brain before birth, because that’s when the entire road map is laid down.

All this, of course, clarifies the ongoing battle of the sexes. What a relief!