The Male Brain

  as much as threefold : Zhang 2007 found a surprising result. These so-called impotence drugs not only block the PDE-5 enzyme to aid erection, but can also boost levels of oxytocin.

  beneficial reduction in blood pressure: Holt-Lunstad 2008 found that the influence of a warm touch enhancement intervention among married couples improves blood pressure, oxytocin, alpha amylase, and cortisol. But only husbands in the intervention group had significantly lower post-treatment twenty-four-hour systolic blood pressure than the control group. McGlone 2007 found that soft touches also activate a class of slow unmylenated nerves that send messages back to the brain's insular cortex, limbic system, and orbitofrontal cortex. These nerves give a pleasant sensation from light touch, and when the skin is lightly stroked, the brain interprets it as emotional touch.

  for every one critical remark : Gottman 2006 found that the marriages of couples having a videotaped conflict were more likely to survive if they made roughly five positive, complimentary comments for every one negative, critical comment. Carrere 1999 found that it was possible to predict a good or bad marital outcome over a six-year period using just the first three minutes of data. They found that couples who used a ratio of five positive comments to one technique) had marriages improved.

  negative (the Gottman

  that survived and even

  letting go of them: St. Jacques 2009. "wisdom does come with age": Mather 2005 found that as people get older, they experience fewer negative emotions. They say that this "positivity effect" in older adults' past memories, compared with younger people, seems to be implemented by cognitive control mechanisms that enhance positive and diminish negative thinking. For more on the positivity effect in older brains, see Ashley 2009, Charles 2008, Nielsen 2008, Dreher 2008, and Samanez-Larkin 2007.

  The Grandfather Brain: Szinovacz 1998b found that grandparenthood is initially a dual process signifying both the transition to parenthood for the adult child and the transition to being a grandparent for his/her parents. For more on similarities in the responses of men and women to grandparenthood, see King 1998b.

  been when Ali was born : Beauregard 2009 found that the neural basis of unconditional love shows that romantic love and parental love are mediated by regions specific to each, as well as overlapping regions in the brain's reward system.

  or the stage of generativity: Vaillant 2002. Vaillant wanted to explore how men adapt to circumstances over a lifetime. The average age of the Harvard men is now eighty-seven. He has concluded that in these men, sustaining warm, close relationships turned out to be a powerful predictor of successful aging.

  food from old to young: Kaplan 1997.

  love for their adult children: Roberto 2001.

  their adult children, and grandchildren: Kivett 1998.

  relationship between grandparents and grandchildren: Silverstein 2001 and Szinovacz 1998b. Jiang 2007 found that grandparents were dominant in shaping children's eating behavior in three-generation families.

  APPENDIX: THE MALE BRAIN AND SEXUAL ORIENTATION

  males as in straight males: Swaab 1990.

  reacts with the developing brain: Swaab 1995.

  males than in straight males: Allen 1992.

  of the straight male brain: Savic 2008.

  in gay and straight men: LeVay 1991 and Kinnunen 2004.

  straight women on such tasks: Rahman 2005 and 2008. to the face of a man: Swaab 2009.

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