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Harvey Milkman, Ph.D.
Harvey Milkman Ph.D.

What Makes Tigers Jump?

What Makes Tigers Jump?

Oxytocin, Dopamine, and Phenylethylamine

Tiger, tiger, burning bright
In the forests of the night
What immortal hand or eye
Could frame thy fearful symmetry?

From: The Tiger
William Blake (1757-1827)

K. Axen

Of the delights of this world, man cares most for sexual intercourse. He will go to any length for it-risk fortune, character, reputation, life itself. - Mark Twain

Whether Tiger Woods did or did not cheat on his wife is irrelevant. In the wake of l'affaire hydrant and his subsequent admission, "... I regret those transgressions with all of my heart..." our natural focus turns to understanding the nature of extra-marital affairs, promiscuity, sexual addiction, and infidelity.

Love or Addiction: In proper proportion, the majestic clockwork of love-a synchronized blend of arousal, satiation, and fantasy-gives rise to life's most fulfilling experience. By nature, we become impassioned by elements that create or sustain life. But all too often the delicate process goes amiss: angels transform into devils, joy becomes jealousy, and heaven changes to hell. As Tiger is likely to know, the nightmare of tormenting love is a miscarriage of our natural attraction toward people who evoke feelings of safety and pleasure. Haywire neurotransmission underlies a bevy of irrational thoughts and actions.

Those who become dependent on romance usually lack confidence in their ability to cope without some form of support, either real or imagined, from a love object. Klein and Liebowitz (1979) of the New York State Psychiatric Institute have proposed the term hysteroid dysphoria-a chronic and intense form of lovesickness-as a category of mental disturbance. The disorder, which they have observed with surprising frequency in the course of their psychiatric practice, is characterized by depression, depletion of energy, and increased appetite in response to feelings of rejection. Conversely, when a romantic figure shows only minimal signs of approval, hysteroids react with increased energy and euphoria. People who suffer from this disturbance seem to fall in love more easily than others, and with less discretion. Their moods are marked by great sensitivity to even the slightest sign of disapproval, particularly from people in whom they have made romantic investments.

If you seem to have more than an academic interest in this syndrome, then perhaps you may be questioning your own propensity as a love addict. Fear not, nearly everyone has a similar reaction: "Is that me?" Don't forget, however, that you can have mild, moderate, or severe degrees of love dependence, as with addiction to food, drugs, or alcohol, and the symptoms are remarkably the same. If your relationship meets three or more of the criteria listed below, then love may be your Achilles heel.

Denial. Your friends and family say you're in a bad relationship, but you don't agree.
 Immediacy. You require frequent emergency "pow-wows" with your lover in social and business situations.
 Compulsion. You've broken up (seriously) at least twice, yet you always make up.
 Loss of Control. You often feel powerless to control your feelings or behavior with regard to your lover.
 Progression. Over time you suspect that your relationship has been on a downward spiral.
 Withdrawal. You become depressed and experience physical disturbance (loss of sleep or altered eating and drinking patterns) when distanced from your lover.

Neurochemistry of Romance: While the language of love is undoubtedly poetry, the language of the brain is chemistry. We respond chemically to other human beings. In fact romantic attachment has been attributed in part to oxytocin, a hormone first released when the baby is nursing and in subsequent love connections throughout life.

Love itself has become a legitimate target for neurochemical analysis. Anthropologists at Rutgers University recruited subjects who claimed to be "madly in love" for an average of 7 months (Fisher, Aron, & Brown, 2005). Each was shown a neutral photo and one of their beloved. MRI data showed that love lights up the caudate nucleus which is home to a rich network of dopamine receptors.

In the right proportions, dopamine creates intense energy, exhilaration, focused attention, and motivation to win rewards. It is why, when you are newly in love, you can stay up all night, watch the sun rise, run a race, ski fast down a slope ordinarily too steep for your skill. Love makes you bold, makes you bright, makes you run real risks, which you sometimes survive and sometimes you don't (Slater, p. 35). Surging levels of dopamine and norepinephrine, that electrify the reward centers of the brain, are referred to by the French as la coup de foudre (‘lightning bolt').

Acording to Liebowitz (1983), author of The Chemistry of Love, a substance known to biochemists as phenylethylamine or PEA is released in the brain when we fall in love. The PEA molecule, which is considered an excitatory amine, bears striking structural similarity to the pharmaceutically manufactured stimulant amphetamine. Liebowitz regards the accelerated use of PEA, which occurs during infatuation, as the key to feelings of excitation, exhilaration, and euphoria.

Rapidly advancing brain science will not be slowed by the sentimental reigns of romance. No matter how mystical we perceive love to be, we are now aware of its neurochemical aspects. Indeed, remarkable biological parallels exist between pathological drug use and the unhealthy need for affection. Becoming dependent on love may be described as a dynamic process with two distinct biochemical phases: infatuation and attachment.

Infatuation is usually an experience of heightened energy and feelings of euphoria. According to Liebowitz (1983), the initial period of psychosexual attraction produces increased concentrations of the neurotransmitter-like substance phenylethylamine (PEA). The brain responds to this chemical in much the same fashion that it would to amphetamine or cocaine; infatuated lovers seem to experience boundless energy, elation, and a remarkable sense of well-being. They have no problem in "painting the town red," then going to work, then going out the following night and doing it all over again.

After a short time, however, the speedy feeling appears to reach a maximum level, and lovers begin to recognize that their relationship is on a plateau. The romance remains exciting, yet the remarkable sensations of invigoration and euphoria appear to be dwindling. In chemical terms, the pleasure of falling in love is derived not from increased production of PEA, but rather from steady increases in the rate of PEA production. When PEA acceleration reaches zero, that is, when increments in the rate of chemical reward have stopped, the honeymoon is over. Although there is obviously great variation between couples. some speculate that the infatuation phase is timed to expire in about 18 months.

At this juncture, one of two possible biochemical processes becomes operative: amphetamine-like withdrawal, or a shift to an endorphin-mediated relationship. Long-term lovers are able to make the transition from zooming around in the fast lane to enjoying cuddles and quiet evenings at home. But consider the chemistry of contentment. The prolonged love-swoon is, after all, an opiate-mediated experience. If one member of the relationship is a "dyed in the wool" arousal type, he or she may seek excitement from people and places outside the relationship. The pair-bond may dissolve as one or the other partner subjectively experiences boredom, stagnation and depression.

So, perhaps, we are a wee bit closer to understanding what makes Tigers jump!

About the Author
Harvey Milkman, Ph.D.

Dr. Harvey Milkman is professor of psychology at Metropolitan State College of Denver specializing in cognitive-behavioral approaches to mood alteration.

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