ENDNOTES

1 “Study: ‘Love Hormone” Roused by Social Media.” Fox News Health online, www.foxnews.com/health/2012/07/12/study-love-hormone-roused-by-social-media/#ixzz2I3mXafFt.

2 Irion, Robert. “What Proxmire’s Golden Fleece Did for—and to—Science.” The Scientist, Dec. 12, 1988.

3 Safire, William. Lend Me Your Ears: Great Speeches in History. New York: W. W. Norton & Co., 1992.

4 Carey, Benedict. “Watching New Love as It Sears the Brain.” New York Times. May 31, 2005.

5 Kaufman, J. C., and L. A. Rosenblum. “The reaction to separation in infant monkeys: Anaclitic depression and conservation withdrawal.” Psychosomatic Medicine 29 (6) (1967): 648–75.

6 Crandall, Floyd, MD. “Hospitalism.” Archives of Pediatics 14(6) (June 1897): 448–54.

7 Ibid.

8 Fisher, Helen, et al. “Romantic love: A mammalian brain system for mate choice.” Philos Trans R Soc Lond B Biol Sci 361(1476) (2006): 2173–86.

9 Ibid.

10 Cannon, C., and M. R. Bseikri. “Is Dopamine Required for Natural Reward?,” Physiology & Behavior 81, no. 5 (July 2004): 741–48.

11 Acevedo, B., et al. “Neural correlates of long-term intense romantic love.” Social Cognitive and Affective Neuroscience 7(2) (Feb. 2012): 149–59.

12 “Sierra Nevada Bighorn Sheep Facts.” (n.d.) Retrieved November 20, 2012, from http://www.dfg.ca.gov/snbs/SheepFacts.html.

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14 Slatcher, R., et al. “Testosterone and Self-Reported Dominance Interact to Influence Human Mating Behavior.” Social Psychological and Personality Science (Feb 28, 2011).

15 Abramov, Israel, et al. “Sex & Vision I: Spatio-temporal Resolution.” Biology of Sex Differences 3(1) (2012).

16 Gibbons, Ann. “The Brain as ‘sexual organ.’” Science (Aug. 30, 1997): 957.

17 Panzica, G. C. “The sexually dimorphic medial preoptic nucleus of quail: A key brain area mediating steroid action on male sexual behavior.” Front Neuroendocrinol 17(1) (Jan. 1996): 51–125.

18 Ibid.

19 Hofman, Michel, et al. “The sexually dimorphic nucleus of the preoptic area.” Journal of Anatomy 164 (1989): 55–72.

20 Gibbons, Ann. “The Brain as ‘sexual organ.’” Science (Aug. 30, 1997): 957.

21 Houtsmuller, E. J., et al. “SDN-POA volume, sexual behavior, and partner preference of male rats affected by perinatal treatment with ATD.” Physiol Behav 56(3) (Sep. 1994): 535–41.

22 Xiaohang, X., et al. “Modular Genetic Control of Sexually Dimorphic Behaviors.” Cell 148(3) (Feb. 3, 2012): 596–607.

23 Cezario, A. F., et al. “Hypothalamic sites responding to predator threats—the role of the dorsal premammillary nucleus in the unconditioned and conditional antipredatory defensive behavior.” Eur J Neuroscience 28(5) (Sep. 2008): 1003–15.

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26 Neufang, Susanne, et al. “Sex Differences and the Impact of Steroid Hormones on the Developing Human Brain.” Cerebral Cortex 19(2) (2009): 464–73.

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29 Gron, G., et al. “Brain activation during human navigation: gender-different neural networks as substrate of performance.” Nature Neuroscience 3(4) (Apr. 2000): 404.

30 Gibbons, Ann. “The Brain as ‘sexual organ.’” Science (Aug. 30, 1997): 957.

31 Neufang, Susanne, et al. “Sex Differences and the Impact of Steroid Hormones on the Developing Human Brain.” Cerebral Cortex 19(2) (2009): 464–73.

32 Starr, C. Basic Concepts in Biology 5e. Belmont, Cal.: Wadsworth Group, 2003.

33 Abramov, Israel, et al. “Sex & Vision I: Spatio-temporal Resolution.” Biology of Sex Differences 3(1) (2012).

34 Giedd, J. N., et al. “Quantitative MRI of temporal lobe, amygdala, and hippocampus in normal human development: ages 4-18 years.” J Comp Neurol 366 (1996): 223–30.

35 St. Jacques, Peggy, et al. “Gender differences in autobiographical memory for everyday events: Retrieval elicited by SenseCam Images vs. Verbal Cues.” Memory 19(7) (Oct. 2011): 723–732.

36 Neufang, Susanne, et al. “Sex Differences and the Impact of Steroid Hormones on the Developing Human Brain.” Cerebral Cortex 19(2) (2009): 464–73.

37 Greitemeyer, T., et al. “Romantic motives and risk-taking: an evolutionary approach.” Journal of Risk Research 16(1) (2013): 19.

38 Dutton, D., and A. Aron. “Some Evidence for Heightened Sexual Attraction Under Conditions of High Anxiety.” Journal of Personality and Social Psychology 30(4) (1974): 510–17.

39 Liston, C., et al. “Psychosocial Stress Reversibly Disrupts Prefrontal Processing and Attentional Control.” Proceedings of the National Academy of Sciences 106(3) (2009): 912.

40 Ibid.

41 Mather, M., and N. R. Lighthall. “Both Risk and Reward Are Processed Differently in Decisions Made Under Stress.” Current Directions in Psychological Science 21(2) (2012).

42 Loh, H., et al. “Beta-endorphin is a potent analgesic agent.” Proc Natl Acad Sci USA 73(8) (Aug. 1976): 2895–98.

43 “Halle Berry and nine other celebrity women who are unlucky in love.” OK! Magazine, Oct. 23, 2012.

44 Arseniuk, M. “Pamela Anderson and Tommy Lee Take Vegas Together.” Las Vegas Sun, Aug. 2, 2009.

45 Wells, Melody S. “Pamela Anderson and Tommy Lee Back Together Again.” People, Jun. 13, 2008. http://www.people.com/people/article/0,,20206681,00.html. Retrieved Jun. 16, 2008.

46 Simpson, J. A., et al. “The Impact of Early Interpersonal Experience on Adult Romantic Relationship Functioning: Recent Findings From the Minnesota Longitudinal Study of Risk and Adaptation.” Current Directions in Psychological Science 20(6) (2011): 355. DOI: 10.1177/09637214118468.

47 Bereczkei, Tamás, et al. “Sexual imprinting in human mate choice.” Proc Biol Sci 271(1544) (Jun 7, 2004).

48 McClintock, Elizabeth. “Handsome Wants as Handsome Does: Physical Attractiveness and Gender Differences in Revealed Sexual Preferences.” Biodemography and Social Biology 57(2) (2011): 221.

49 Bereczkei, Tamás, et al. “Sexual imprinting in human mate choice.” Proc Biol Sci 271(1544) (Jun 7, 2004).

50 Shepher, Joseph. Incest: A Biosocial View. (Studies in Anthropology.) New York: Academic Press, 1983.

51 Fisher, Helen, et al. “The Neural Mechanisms of Mate Choice: A Hypothesis.” Neuroendocrinology Letters Special Issue 23(suppl 4) (Dec. 2002).

52 Abramov, Israel, et al. “Sex & Vision I: Spatio-temporal Resolution.” Biology of Sex Differences 3(1) (2012).

53 Holding, Cathy. “The Science of Magnetism.” The Independent, September 12, 2008.

54 Provine, Robert R., et al. “When the Whites of the Eyes are Red: A Uniquely Human Cue.” Ethology 117(5) (2011).

55 Buss, David, et al. “Sexual Strategies Theory: An Evolutionary Perspective on Human Mating.” Psychological Review 100(2) (1993): 204–32.

56 Brizendine, Louann. The Male Brain. New York: Random House, 2010.

57 Grammer, Karl, et al. “Human pheromones and sexual attraction.” European Journal of Obstetrics & Gynecology and Reproductive Biology 118(2) (Feb. 1, 2005): 135–142.

58 Meredith, Michael. “Human Vomeronasal Organ Function: A Critical Review of Best and Worst Cases.” Chem. Senses 26(4) (2001): 433–445.

59 Panevich, Diana, et al. “Effects of Vomeronasal Organ Removal From Male Mice on Their Preference for and Neural Fos Responses to Female Urinary Odors.” Behavioral Neuroscience 120(4) (Aug. 2006): 925–936.

60 Miller, Saul, et al. “Scent of a Woman: Men’s Testosterone Responses of Olfactory Ovulation Cues.” Psychological Science 21(2) (2010): 276–83.

61 Clutton-Brock, Tim. “Female Mate Choice in Mammals.” The Quarterly Review of Biology 84(1) (2009).

62 Van Bergen, E., et al. “The scent of inbreeding a male sex pheromone betrays inbred males.” Proc Biol Sci 280(1758) (2013).

63 Cardiff University. (2005, April 2). “Love at First . . . Smell.” ScienceDaily, Apr. 2, 2005. www.sciencedaily.com/releases/2005/03/050326094405.htm. Retrieved Aug. 2, 2013.

64 Penn, Dustin, et al. “The Evolution of Mating Preferences and Major Histocompatibility Complex Genes.” The American Naturalist 153(2) (Feb. 1999).

65 Xu, Yi, et al. “Human Vocal Attractiveness as Signaled by Body Size Projection.” PLoS ONE 8(4) (2013).

66 Smith, D. S., et al. “A modulatory effect of male voice pitch on long-term memory in women: Evidence of adaptation of mate choice?” Memory & Cognition 40 (2012).

67 Guéguen, N., et al. “‘Love is in the air’: Effects of songs with romantic lyrics on compliance with a courtship request.” Psychology of Music 38(3) (2010).

68 Woollaston, Victoria. “Musicians really are sexier: Scientists find that carrying a guitar increases your chances of getting a date by a third.” DailyMail, May 7, 2013.

69 Farley, S., et al. “People Will Know We Are in Love: Evidence of Differences Between Vocal Samples Directed Towards Lovers and Friends.” Journal of Nonverbal Behavior 37(3) (2013): 123.

70 Charles, Dan. “Study Links Warm Hands, Warm Heart.” All Things Considered. NPR radio. Oct. 25, 2008.

71 Williams, Lawrence, et al. “Experiencing Physical Warmth Promotes Interpersonal Warmth.” Science 322(5901) (Oct. 24, 2008): 606–7.

72 Ackerman, Joshua, et al. “Incidental Haptic Sensations Influence Social Judgements and Decisions.” Science 328(5986) (Jun. 25, 2010): 1712–15.

73 Hughes, Susan, et al. “Sex Differences in Romantic Kissing Among College Students: An Evolutionary Perspective.” Evolutionary Psychology 5(3) (2007): 612–31.

74 Craig, A. D. “How do you feel—now. The anterior insula and human awareness.” Nat Rev Neurosci 10(1) (Jan 2009): 59.

75 Deen, Ben, et al. “Three Systems of Insular Functional Connectivity Identified with Cluster Analysis.” Cerebral Cortex 21(7) (Epub Nov. 19, 2010).

76 Chan, Kai Qin, et al. “What do Love and Jealousy Taste Like?” Emotion 3(16) (Dec. 2013).

77 Statistic Brain Research Institute. “Online Dating Statistics.” (2016) http://www.statisticbrain.com/online-dating-statistics/.

78 Cooper, J. C., et al. “Dorsomedial prefrontal cortex mediates rapid evaluations predicting the outcome of romantic interactions.” Journal of Neuroscience 32 (Nov. 7, 2012).

79 Sundie, Jill, et al. “Peacocks, Porsches, and Thorstein Veblen: Conspicuous consumption as a sexual signaling system.” Journal of Personality and Social Psychology 100(4) (Apr. 2001): 664–680.

80 Tracy, Jessica, and Alec Beall. “Happy guys finish last, says new study on sexual attractiveness.” Emotion 11(6) (2011).

81 Fisher, Helen. “Lust, Attraction, and Attachment in Mammalian Reproduction.” Human Nature 9(1) (1998): 23–52.

82 Confer, Jaime, et al. “More than just a pretty face: men’s priority shifts toward bodily attractiveness in short-term versus long-term mating contexts.” Evolution and Human Behavior 31(5) (2010): 348.

83 Elliot, A., et al. “Red, Rank and Romance in Women Viewing Men.” Journal of Experimental Psychology: General 139(3) (2010): 399–417.

84 University of Toronto. “New ‘golden ratios’ for female facial beauty.” ScienceDaily (Dec. 17, 2009). www.sciencedaily.com/releases/2009/12/091216144141.htm. Retrieved September 6, 2013.

85 Blackburn, K., et al. “Emotive hemispheric differences measured in real-life portraits using pupil diameter and subjective aesthetic preferences.” Experimental Brain Research 219(4) (2012).

86 “Study: ‘Love Hormone” Roused by Social Media.” Fox News Health online, www.foxnews.com/health/2012/07/12/study-love-hormone-roused-by-social-media/#ixzz2I3mXafFt.

87 Grant, Alexis. “One in Three Female Online Daters Report First-Date Sex.” Houston Chronicle, August 30, 2007.

88 Association for Psychological Science. “All it takes is a smile (for some guys).” ScienceDaily (Dec. 14, 2011). www.sciencedaily.com/releases/2011/12/111213132001.htm. Retrieved June 4, 2013.

89 van der Meij, L., et al. “Men with elevated testosterone levels show more affiliative behaviors during interactions with women.” Proc Biol Sci 279(1726) (Jan. 7, 2012): 202–208.

90 Fisher, Helen, et al. “Romantic love: A mammalian brain system for mate choice.” Philos Trans R Soc Lond B Biol Sci 361(1476) (2006): 2173–86.

91 Gingrich, B., et al. “Dopamine D2 receptors in the nucleus accumbens are important for social attachment in female prairie voles (Microtus ochrogaster).” Behavioral Neuroscience 114 (2000): 173–183.

92 Zhang, Lifen, et al. “Withdrawal from Chronic Nicotine Exposure Alters Dopamine Signaling Dynamics in the Nucleus Accumbens. Biological Psychiatry 71(3) (2012).

93 Young, L., et al. “The neurobiology of pair bonding.” Nature Neuroscience 7(10) (Oct. 2004): 1048–54.

94 Ibid.

95 Ibid.

96 Kringelbach, Morten, and Kent Berridge. “The Functional Neuroanatomy of Pleasure and Happiness.” Discovery Medicine NIH Public Access publication, Dec. 22, 2010. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3008353.

97 Skloot, Rebecca. “How to Change Your Bad Habits.” O, The Oprah Magazine, Jan. 2007.

98 Cannon, C., et al. “Is dopamine required for natural reward?” Physiology & Behavior 81(5) (Jul. 2004): 741–8.

99 Fiorino, Dennis, et al. “Dynamic Changes in Nucleus Accumbens Dopamine Efflux During the Coolidge Effect in Male Rats.” Journal of Neuroscience 17(12) (Jun. 15, 1997): 4849–55.

100 Young, L., et al. “The neurobiology of pair bonding.” Nature Neuroscience 7(10) (Oct. 2004): 1048–54.

101 Ibid.

102 Nagasawa, N., et al. “Dog’s gaze at its owner increases owner’s urinary oxytocin during social interaction” Hormones and Behavior 55(3) (Mar. 2009): 434–41.

103 Young, L., et al. “The neurobiology of pair bonding.” Nature Neuroscience 7(10) (Oct. 2004): 1048–54.

104 Ibid.

105 Ibid.

106 Mohamed Kabbaj, PhD, personal communication, May, 22, 2015.

107 Love, Tiffany. “Oxytocin, motivation and the role of dopamine.” Pharmacology Biochemistry and Behavior 119 (Apr. 2014): 49–60.

108 Knut, K., et al. “Reward value of attractiveness and gaze.Nature 413 (Oct. 11, 2001).

109 Feldman, R. “Oxytocin and social affiliation in humans” Hormones and Behavior 61(3) (Mar. 2012): 380–90.

110 Walum, H., et al. “Variation in the oxytocin receptor gene is associated with pair-bonding and social behavior.” Biological Psychiatry 71(5) (Mar. 1, 2012): 419–26.

111 Love, Tiffany. “Oxytocin, motivation and the role of dopamine.” Pharmacology Biochemistry and Behavior 119 (Apr. 2014): 49–60.

112 Schneiderman, Inna, et al. “Oxytocin during initial stages of romantic attachment: Relations to couples’ interactive reciprocity.” Psychoneuroendocrinology 37 (2012): 1277–85.

113 Ibid.

114 Dylewski, Adam. “The Chemistry of Love—Reactions.” Video. American Chemical Society (Feb.10, 2014). Retrieved from https://www.youtube.com/watch?v=bp7Ydv5wAPk.

115 Walum, Hasse, et al. “Genetic variation in the vasopressin receptor 1a gene (AVPR1A) associates with pair-bonding behavior in humans.” Proc Natl Acad Sci 105(37) (Sep. 16, 2008).

116 Wang, H., et al. “Histone deacetylase inhibitors facilitate partner preference formation in female prairie vole.” Nature Neuroscience 16(7) (Jul. 2011).

117 Lim, M. “Vasopressin-dependent neural circuits underlying pair bond formation in the monogamous prairie vole.” Neuroscience 125(1) (2004): 35–45.

118 Mazur, A., and A. Booth. “Testosterone and Dominance in Men.” Behavioural and Brain Sciences 21(3) (Jun. 1998): 353–63.

119 Burnham, T. C., et al. “Men in committed, romantic relationships have lower testosterone.” Hormones and Behavior 44(2) (Aug. 2003): 119–22.

120 Icahn School of Medicine, Neuroscience Department, Nestler Lab. Brain Reward Pathways. http://neuroscience.mssm.edu/nestler/brainRewardpathways.html.

121 Fisher, Helen, et al. “Romantic love: A mammalian brain system for mate choice.” Philos Trans R Soc Lond B Biol Sci 361(1476) (2006): 2173–86.

122 The top 20 Traits Women Want in a Man 6/16/15 MSN.com retrieved from http://www.msn.com/en-us/lifestyle/love-sex/the-top-20-traits-women-want-in-a-man.

123 Mobbs, D., et al. “Humor Modulates the Mesolimbic Reward Centers.” Neuron 40(5) (Dec. 4, 2003): 1041–48.

124 Kosfeld, M., et al. “Oxytocin increases trust in humans.” Nature 435 (Jun. 2, 2005): 673–76.

125 Kirsch, P., et al. “Oxytocin modulates neural circuitry for social cognition and fear in humans.” Journal of Neuroscience 25(49) (Dec. 2005): 11489–93.

126 Rosmarin, David, et al. “Incorporating spiritual beliefs into a cognitive model of worry.” Journal of Clinical Psychology 67(7) (2011).

127 Hölzel, B., et al. “Mindfulness practice leads to increases in regional brain gray matter density.” Psychiatry Research: Neuroimaging 191(1) (2011): 36.

128 Van Wingen, Guido, et al. “Testosterone reduces amygdala-orbiotfrontal cortex coupling.” Psychoneuroendrocrinology 33(1) (Jan. 2010).

129 Knight, Emily, et al. “Too Good to Be True: Rhesus Monkeys React Negatively to Better-than-Expected Offers.” PLoS ONE 8(10) (Oct. 9, 2013).

130 University of Missouri–Columbia (2013, May 14) “Male testosterone levels increase when victorious in competition against rivals, but not friends.” Science Newsline: Psychology. http://www.sciencenewsline.com/news/2013051415000074.html. Retrieved Sep. 16, 2013.

131 Trumble, Benjamin, et al. “Age-independent increases in male salivary testosterone during horticultural activity among Tsimane forager-farmers.” Evolution and Human Behavior 34 (2013).

132 University of Missouri–Columbia (2013, May 14) “Male testosterone levels increase when victorious in competition against rivals, but not friends.” Science Newsline: Psychology. http://www.sciencenewsline.com/news/2013051415000074.html. Retrieved Sep. 16, 2013.

133 Schultz, Wolfram. “Dopamine signals for reward and risk: basic and recent data.” Behavioral and Brain Functions 6(24) (2010).

134 W. Schultz, personal correspondence, December 3, 2015.

135 American Academy of Neurology. “Dopamine-related Drugs Affect Reward-seeking Behavior.” ScienceDaily (Apr. 30, 2007). www.sciencedaily.com/releases/2007/04/070427072318.htm. Retrieved July 12, 2013.

136 Zeki, S. “The Neurobiology of Love.” FEBS Letters 581 (2007): 2575–79.

137 Fisher, Helen, et al. “Romantic love: A mammalian brain system for mate choice.” Philos Trans R Soc Lond B Biol Sci 361(1476) (2006): 2173–86.

138 Phelan, Jay. What is Life? A Guide to Biology. New York: W. H. Freeman, 2010: 355.

139 Ibid.

140 Liza, A., et al. “Perception of male-male competition influences Drosophila copulation behavior even in species where females rarely remate.” Biology Letters (2011).

141 Brehrendt, Greg, and Liz Tuccillo. He’s Just Not That Into You: The No-Excuse Truth to Understanding Guys. New York: Simon Spotlight Entertainment, 2004.

142 Ibid.

143 Clark, Russell, et al. “Gender Differences in Receptivity to Sexual Offers.” Journal of Psychology & Human Sexuality 2(1) (1989).

144 Zeki, S. “The Neurobiology of Love.” FEBS Letters 581 (2007): 2575–79.

145 Russell, Steve. “Online dating relationship ends badly, $1.3M later.” The Star, Jul. 11, 2014.

146 Wyart, C., et al. “Smelling a single component of male sweat alters levels of cortisol in women.” J. Neurosci 27(6) (Feb. 7, 2007): 1261–5.

147 Tom, S., et al. “The Neural Basis of Loss Aversion in Decision-Making Under Risk.” Science 315 (Jan. 26, 2007).

148 Sage Publications. “Friendship, Timing Key Differences Between US, Eastern European Love.” ScienceDaily, Aug. 17, 2011. (Summary of de Munck, V. C., et al., Cross-Cultural Research 45(2), 2011.)

149 Wang, H., et al. “Histone deacetylase inhibitors facilitate partner preference formation in female prairie vole.” Nature Neuroscience 16(7) (Jul. 2011).

150 Severo, Richard. “William Proxmire, Maverick Democratic Senator From Wisconsin, Is Dead at 90.” New York Times, Dec. 16, 2005.

151 Zeki, S. “The Neurobiology of Love.” FEBS Letters 581 (2007): 2575–79.

152 Bartels, Andreas, et al. “The neural correlates of maternal and romantic love.” NeuroImage 21 (2004): 1155–66.

153 Zeki, S. “The Neurobiology of Love.” FEBS Letters 581 (2007): 2575–79.

154 Loyola University Healthy System. “What falling in love does to your heart and brain.” ScienceDaily, Feb. 6, 2014.

155 Bartels, Andreas, et al. “The neural correlates of maternal and romantic love.” NeuroImage 21 (2004): 1155–66.

156 Zeki, S. “The Neurobiology of Love.” FEBS Letters 581 (2007): 2575–79.

157 Xiaomeng, X., et al. “Regional brain activity during early-stage intense romantic love predicted relationship outcomes after 40 months: An fMRI assessment.” Neuroscience Letters 526 (2012): 33–38.

158 Lynch, Dennis. “Valentine’s Day Jailbreak: Joseph Andrew Dekenipp Escaped Jail to Meet His Girlfriend at Saloon.” International Business Times Feb. 19, 2014. http://www.ibtimes.com/valentines-day-jailbreak-joseph-andrew-dekenipp-escaped-jail-meet-his-girlfriend-saloon-1555826.

159 D’Argembeau, Arnaud. “On the Role of the Ventromedial Prefrontal Cortex in Self-Processing: The Valuation Hypothesis.” Frontier of Human Neuroscience 7 (2013): 372.

160 Zeki, S. “The Neurobiology of Love.” FEBS Letters 581 (2007): 2575–79.

161 Van Steenbergen, Henk, et al. “Reduced cognitive control in passionate lovers.” Motivation and Emotion 38(3) (2014).

162 Zeki, S. “The Neurobiology of Love.” FEBS Letters 581 (2007): 2575–79.

163 Bartels, Andreas, et al. “The neural basis of romantic love.” NeuroReport 11(27) (Nov. 2000).

164 McIntyre, Matthew, et al. “Romantic involvement often reduces men’s testosterone levels—but not always: the moderating role of extrapair sexual interest.” Journal of Personality and Social Psychology 91(4) (2006): 642–51.

165 Ananthaswamy, Anil. “Love, the great gender bender.” New Scientist, May 8, 2004.

166 Law, Bridget Murray. “Hormones & desire: Hormones associated with the menstrual cycle appear to drive sexual attraction more than we know.” American Psychological Association 42(3) (Mar. 2011).

167 Gray, Peter, et al. “Human Male Pair Bonding and Testosterone.” Human Nature 15(2) (Jun. 2004): 119–31.

168 Panzica, G. C. “The sexually dimorphic medial preoptic nucleus of quail: A key brain area mediating steroid action on male sexual behavior.” Front Neuroendocrinol 17(1) (Jan. 1996): 51–125.

169 Baskerville, T., and A. Douglas. “Dopamine and Oxytocin Interactions Underlying Behaviors: Potential on Contributions to Behavioral Disorders.” CNS Neuroscience & Therapeutics 16(3) (2010).

170 Schneiderman, Inna, et al. “Oxytocin during initial stages of romantic attachment: Relations to couples’ interactive reciprocity.” Psychoneuroendocrinology 37 (2012): 1277–85.

171 Ibid.

172 Gravotta, Luciana. “Be Mine Forever: Oxytocin May Help Build Long-Lasting Love.” Scientific American, Feb. 12, 2013.

173 Ibid.

174 “The ‘love hormone’ oxytocin may keep men faithful in relationships.” NY Daily News, Nov. 15, 2012.

175 Scheele, Dirk, et al. “Oxytocin enhances brain reward system responses in men viewing the face of their female partner.” Proc Natl Acad Sci 110(50) (2013).

176 Neumann, Inga. “Oxytocin: The Neuropeptide of Love Reveals Some of Its Secrets.” Cell Metabolism 5(4) (Apr. 2007).

177 Marazziti, Donatella, et al. “Hormonal changes when falling in love.” Psychoneuroendocrinology 29(7) (Aug. 2004): 931–36.

178 Ibid.

179 Zeki, S. “The Neurobiology of Love.” FEBS Letters 581 (2007): 2575–79.

180 Meloy, J. Reid, et al. “Some Thoughts on the Neurobiology of Stalking.” Journal of Forensic Science 50(6) (Nov. 2005).

181 Zeki, S. “The Neurobiology of Love.” FEBS Letters 581 (2007): 2575–79.

182 Fisher, Helen. “Lust, Attraction, and Attachment in Mammalian Reproduction.” Human Nature 9(1) (1998): 23–52.

183 Loving, Timothy, et al. “Passionate love and relationship thinkers: Experimental evidence for acute cortisol elevations in women.” Psychoneuroendocrinology 34(6) (2009): 939–46.

184 Ibid.

185 Kirschbaum, C., et al. “Impact of gender, menstrual cycle phase, and oral contraceptives on the activity of the hypothalamus-pituitary-adrenal axis.” Psychosomatic Medicine 61(2) (Mar.-Apr. 1999): 154–62.

186 Younger, Jarred, et al. “Viewing Pictures of a Romantic Partner Reduces Experimental Pain: Involvement of Neural Reward Systems.” PLoS ONE (Oct. 13, 2010).

187 Ibid.

188 Koneru, Amupama, et al. “Endogenous Opioids: Their Physiological Role and Receptors.” Global Journal of Pharmacology 3(3) (2009): 149–53.

189 Bayliss, Kelly. “Couple Caught Having Sex on Chipotle Roof: Police.” NBC10.com. http://www.nbcphiladelphia.com/news/local/Couple-Arrested-for-Having-Sex-on-Chipotle-Roof-267032481.html.

190 Koneru, Amupama, et al. “Endogenous Opioids: Their Physiological Role and Receptors.” Global Journal of Pharmacology 3(3) (2009): 149–53.

191 Emanuele, Enzo, et al. “Raised plasma nerve growth factor levels associated with ­early-stage romantic love.” Psychoneuroendocrinology 31(3) (2006): 288–94.

192 Ibid.

193 Marazziti, D., et al. “Research Letter: Brain-derived neurotropic factor in romantic attachment.” Psychological Medicine 39 (2009): 1927–30.

194 Ibid.

195 Vargas-Perez, Hector, et al. “Ventral Tegmental Area BDNF Induces an Opiate-Dependent-Like Reward State in Naïve Rats.” Science 324(5935) (Jun. 26, 1009): 1732–34.

196 Aron, Arthur, et al. “Falling in Love: Prospective Studies of Self-Concept Change.” Journal of Personality and Social Psychology 69(6) (1995): 1102–12.

197 Koneru, Amupama, et al. “Endogenous Opioids: Their Physiological Role and Receptors.” Global Journal of Pharmacology 3(3) (2009): 149–53.

198 Zeki, S. “The Neurobiology of Love.” FEBS Letters 581 (2007): 2575–79.

199 Marazziti, Donatella, and Stefano Baroni. “Romantic love: the mystery of its biological roots.” Clinical Neuropsychiatry 9(1) (Feb.-Mar. 2012).

200 de Boer, A., et al. “Love is more than just a kiss: A neurobio­logical perspective on love and affection.” Neuroscience 201 (2012): 114–24.

201 Marazziti, Donatella, et al. “Hormonal changes when falling in love.” Psychoneuroendocrinology 29(7) (Aug. 2004): 931–36.

202 Ibid.

203 Acevedo, B., et al. “Neural correlates of long-term intense romantic love.” Social Cognitive and Affective Neuroscience 7(2) (Feb. 2012): 149–59.

204 Fisher, H. E. “The Nature of Romantic Love.” Journal of NIH Research 6(4) (1994): 59–64.

205 Bartels, Andreas, et al. “The neural basis of romantic love.” NeuroReport 11(27) (Nov. 2000).

206 Ramachandran, V. S. The Tell-Tale Brain: A Neuroscientist’s Quest for What Makes Us Human. New York: W. W. Norton, 2011.

207 Acevedo, B., et al. “Neural correlates of long-term intense romantic love.” Social Cognitive and Affective Neuroscience 7(2) (Feb. 2012): 149–59.

208 Ibid.

209 Beauregard, M., et al. “The neural basis of unconditional love.” Psychiatry Research: Neuroimaging 172(2) (May 15, 2009): 93–98.

210 Moll, J., et al. “The Neural Correlates of Moral Sensitivity: A Functional Magnetic Resonance Imaging Investigation of Basic and Moral Emotions.” Journal of Neuroscience 22(7) (Apr. 1, 2002): 2730–36.

211 Takahashi, Hidehiko, et al. “Neural Correlates of Human Virtue Judgment.” Cerebral Cortex 18(8) (Aug. 2008): 1886–91.

212 Engstrom, M., et al. “Brain Activation During Compassion Meditation: A Case Study.” Journal of Alternative and Complementary Medicine 16(5) (May 2010): 597–99.

213 Gonzaga, Gian, et al. “Love, desire, and the suppression of thoughts of romantic alternatives.” Evolution and Human Behavior 29 (2008): 119–26.

214 Pronk, T., et al. “How can you resist? Executive control helps romantically involved individuals to stay faithful.” Journal of Personality and Social Psychology 100(5) (May 2011): 827–37.

215 Matsunaga, M., et al. “Genetic variations in the serotonin transporter gene-linked polymorphic region influence attraction for a favorite person and the associated interactions between the central nervous and immune system. Neuroscience Letters 468 (2010): 211–15.

216 Kiecolt-Glaser, J., et al. “Marriage and Health: His and Hers.” Psychological Bulletin 127(4) (2001): 472–503.

217 Fair, V., et al. “Epigenetic inheritance of a cocaine-resistance phenotype.” Nature Neuroscience 16 (2012).

218 Finn, C., et al. “Recent Decreases in Specific Interpretation Biases Predict Decreases in Neuroticism: Evidence From a Longitudinal Study With Young Adult Couples.” Personality 83(3) (2014).

219 Acevedo, B., et al. “Neural correlates of long-term intense romantic love.” Social Cognitive and Affective Neuroscience 7(2) (Feb. 2012): 149–59.

220 Ibid.

221 Acevedo, B., and A. Aron. “Does a Long-Term Relationship Kill Romantic Love?” Review of General Psychology 13(1) (2009): 59–65.

222 Aron, A., et al. “The experimental generation of interpersonal closeness: a procedure and some preliminary findings.” Personality & Social Psychology Bulletin 23(4) (April 1997): 363.

223 Epstude, Kai, et al. “Seeing love, or seeing lust: How people interpret ambiguous romantic situations.” Journal of Experimental Social Psychology 47 (2011): 1017–20.

224 Marazziti, D., et al. “Research Letter: Brain-derived neurotropic factor in romantic attachment.” Psychological Medicine 39 (2009): 1927–30.

225 Boderman, G., et al. “The role of stress in divorce: A three-nation retrospective study.” Journal of Social and Personal Relationships 24(5) (Oct. 2007): 707–28.

226 Davidson, R., et al. “Social influences on neuroplasticity: stress and interventions to promote well-being.” Nature Neuroscience 15 (2012): 689–95.

227 Ibid.

228 Ibid.

229 Arnsten, A., et al. “This is Your Brain in Meltdown.” Scientific American 306(4) (Apr. 2012): 48–53.

230 Lisitsa, Ellie. “The Four Horsemen: The Antidotes.” Gottman Relationship Blog, The Gottman Institute. https://www.gottman.com/blog/the-four-horsemen-the-antidotes/.

231 Xu, X., et al. “Reward and Motivation Systems: A Brain Mapping Study of Early-Stage Intense Romantic Love in Chinese Participants.” Human Brain Mapping 32 (2011): 249–57.

232 Gaia, V. “Watching the brain ‘switch off’ self-awareness.” The New Scientist, Apr. 19, 2006.

233 Vaillant, G. “Positive Emotions, Spirituality and the Practice of Psychiatry.” Mental Health, Spirituality, Mind 6(1) (2008): 48–62.

234 Ibid.

235 Wolchover, Natalie. “Brain Scans Could reveal If Your Relationship Will Last.” LiveScience, February 14, 2012. http://www.livescience.com/18468-relationship-longevity-brain-scans.html.

236 Ramachandran, V. S. The Tell-Tale Brain: A Neuroscientist’s Quest for What Makes Us Human. New York: W. W. Norton, 2011.

237 Fisher, H. “Lasting Love: The Secret To Long-Term Relationships.” Huffington Post, July 8, 2013.

238 O’Leary, K. D., et al. “Is Long-Term Love More Than A Rare Phenomenon? If So, What Are Its Correlates?” Social Psychological and Personality Science 3(2) (Mar. 2012): 241–249.

239 Holmes, J., et al. “A leap of faith? Positive illusions in romantic relationships.” Personality & Social Psychology Bulletin. 23(6) (June 1997): 586.

240 Ibid.

241 Ibid.

242 Ibid.

243 Ibid.

244 Gigy, Lynn, et al. “Reasons for Divorce: Perspectives of Divorcing Men and Women.” Journal of Divorce & Remarriage 18(1–2), 1993.

245 Acevedo, B., et al. “Neural correlates of long-term intense romantic love.” Social Cognitive and Affective Neuroscience 7(2) (Feb. 2012): 149–59.

246 Ibid.

247 Aron, A., et al. “Couple’s Shared Participation in Novel and Arousing Activities and Experienced Relationship Quality.” Journal of Personality and Social Psychology 78(2) (2000): 273–84.

248 Welker, K., et al. “Effects of self-disclosure and responsiveness between couples on passionate love within couples.” Personal Relationships 21 (2014): 692–708.

249 Ortigue, S., et al. “The neural basis of love as subliminal prime: An event-related fMRI study.” Journal of Cognitive Neuroscience 19(7) (Jul. 2007): 1218–30.

250 Aron, A. “Marital Satisfaction and Passionate Love.” Journal of Social and Personal Relationships 12(1) (Feb. 1995): 139–46.

251 Mazur, A., and A. Booth. “Testosterone and Dominance in Men.” Behavioural and Brain Sciences 21(3) (Jun. 1998): 353–63.

252 Ibid.

253 Vongas, J., et al. “Competing Sexes, Power, and Testosterone: How Winning and Losing Affect People’s Empathic Responses and What this Means for Organizations.” Applied Psychology: An International Review 64(2) (2015): 308–37.

254 Algoe, S., et al. “It’s the Little Things: Everyday Gratitude as a Booster Shot for Romantic Relationships.” Personal Relationships 17 (2010): 217–33.

255 Takahashi, Hidehiko, et al. “Neural Correlates of Human Virtue Judgment.” Cerebral Cortex 18(8) (Aug. 2008): 1886–91.

256 Guerra, P., et al. “Viewing Loved Faces Inhibits Defense Reactions: A Health-Promotion Mechanism?” PLoS ONE 7(7) (2012).

257 Ibid.

258 Baumgarter, T., et al. “Oxytocin Shapes Neural Circuitry to Trust and Trust Adaptations in Humans.” Neuron 58 (May 22, 2008): 639–50.

259 Hiller, J. “Gender differences in sexual motivation.” Journal of Men’s Health & Gender 2(3) (Sep. 2005): 339.

260 Holmes, J., et al. “A leap of faith? Positive illusions in romantic relationships.” Personality & Social Psychology Bulletin. 23(6) (June 1997): 586.

261 Esch, T., et al. “The Neurobiology of Love.” Neuroendrocrinology Letters 26(3) (2005): 175–92.

262 Felix, N., et al. “Satisfaction with Love Life Across the Adult Life Span.” Applied Research in Quality of Life 10(2) (Jun. 2015).

263 Frassica, M. “What is Love? U of L professors apply some hard science to a ‘touchy-feely topic.’” The Courier-Journal, Feb. 9, 2014.