Insomniac readers (yes, you reading this at 3 A.M.), please don't hate me! I just happen to be one of those people who falls asleep minutes after my head hits the pillow and awakens cheery and refreshed when the sunlight filters through the window.

I have always counted this as a blessing (so much better than counting sheep) but never so much as I do in view of our special report on circadian rhythms. Now I find myself wondering if my reliable inner clock also deserves some credit for other aspects of my generally good health: blood pressure, metabolism, digestion, and more. Read “Out of Sync,” by contributing editor Emily Laber-Warren, and you, too, will marvel at the pervasive role that these daily rhythms play in sickness and in health. And consider this astounding fact: timekeeping proteins rise and fall with such precision in our brain that by testing for them in an autopsy, you can pinpoint an individual's time of death.

Timing also plays a vital role in maintaining a healthy body weight. Make a habit of nighttime eating, and you are asking for trouble. In our cover story—“Don't Diet!”—Charlotte N. Markey, a Rutgers University psychologist and weight-loss investigator, dismantles many popular notions of how to shed pounds. Along the way she parses the research on the common psychological traps of dieting. Ironic processing is one example: You decide to give up carbs, and all you can think about is pasta. You cut red meat and obsess about a juicy steak, eventually yielding to temptation. Want to know more about these pitfalls and what weight-loss strategies actually work? Read the article here.

Many of us are familiar with the idea that some kids are like orchids—ultrasensitive to being damaged by an unfavorable environment. In “The Upside of Vulnerability,” developmental psychologist Jay Belsky of the University of California, Davis, shows us the other side of that coin with evidence that these delicate flowers have a surprising hidden strength: they blossom prodigiously when given enriched environments. Belsky calls it a “for better and for worse” pattern and raises provocative questions about what it means for policies aimed at poor and vulnerable children.

There are plenty more surprises blooming in Scientific American Mind's autumn garden. Don't miss the medical detective story: an excerpt from Brain Storms, Jon Palfreman's riveting new book about Parkinson's disease. Take a stroll through our pages and let us know what you think!