Iconoclast: A Neuroscientist Reveals How to Think Differently
Page 23
Another type of steroid hormone that has received a great deal of recent attention as a potential cognitive enhancer is testosterone. Like cortisol, testosterone is derived from cholesterol. In men, it is synthesized primarily in the testes, but women have testosterone too, made in the adrenal glands. Interestingly, the effect of testosterone depends on the age of the person. During puberty, testosterone causes the development of the external genitalia, grows body hair, and increases muscle mass. After about age twenty-five, however, testosterone levels decline steadily, so that it is cut in half by age eighty. As a consequence, the geriatric literature is burgeoning with anecdotal reports that testosterone, taken in late life, is some sort of fountain of youth, restoring failing memory and even staving off Alzheimer’s disease. A chemical precursor to testosterone, DHEA, has received a lot of hype. DHEA was easily available over the Internet or through health stores. The FDA wants to regulate it. But in a two-year double-blind, placebo-controlled study of DHEA and testosterone in elderly men and women, no significant effects were found on either physical or mental function.26 There weren’t even any improvements in quality of life. Although neither testosterone nor DHEA has been conclusively shown to aid memory, testosterone does affect the emotional system of the brain. Neuroscientists in the Netherlands have found that giving a single, sublingual dose of testosterone to healthy women did two things. First, when the women viewed movies of actors making facial expressions of different emotions, the women didn’t subconsiously mimic the actors’ expressions. Normally, when people view these movies, they subconsciously mimic the expressions, implying that testosterone somehow decreased normal empathic responses. Second, testosterone decreased their startle responses by about 20 percent.27 So, although testosterone might make you braver, or at least less prone to being startled, it might also make you a jerk. Plus, if you’re a woman, you’ll start growing chest hair.
Conclusion: testosterone and maybe DHEA do have effects on social and emotional processing (not necessarily in a good way), but their effects on memory are more hype than reality. These hormones don’t appear to have good potential for iconoclasm, and may raise the risk of prostate cancer.
One hormone that might actually live up to the hype is oxytocin. Also secreted by the pituitary gland, oxytocin is released in massive amounts during labor. In women, it strengthens uterine contractions. In animals, oxytocin acts in the amygdala to reduce fear and aggressive behavior. Mice that have been genetically engineered to lack oxytocin show a profound deficit in social recognition behaviors for other mice. In some animals, oxytocin promotes monogamous pair-bonding. In humans, oxytocin can be injected, as when it is used to induce labor, or it can be absorbed intranasally through a small puffer device (Syntocinon).
A handful of recent experiments have unequivocally demonstrated that intranasal oxytocin enhances several aspects of social function in humans. A test called the “Reading the Mind in the Eyes Test” asks the subject to infer a mental state from a picture of someone’s eyes. Most people do pretty well on this, although some pictures are a bit tricky. Interestingly, in a placebo-controlled study, healthy volunteers who received intranasal oxytocin did better on the difficult pictures.28 Another study used an experimental economic procedure called the “trust game.” In this game, two people take turns sending money back and forth. At each turn, the individual has the choice of keeping some money or returning some to the other player. The amount returned triples in value. Thus, there is a financial incentive to return all the money because it will triple, but each player must trust that the other person will do the same. Amazingly, oxytocin increased participants’ willingness to trust other each other.29 Much of this effect seems to be mediated by the amygdala. An fMRI study found that the amygdala activation in response to fear-inducing pictures was decreased by oxytocin.30
Summary: of all the hormones studied, oxytocin appears to have real potential for decreasing fear, especially in social situations. It may augment an individual’s ability to read another person’s intentions, increase empathy, and promote trusting behavior. The side effects appear to be minimal. Because of its labor-inducing properties, oxytocin should definitely not be used by pregnant women.
Summary
So there you have it. The quick road to iconoclasm (well, not really).
Some of the drugs described here may have a limited role in augmenting certain iconoclastic brain functions while diminishing other mental processes that seem to get in the way. The SSRIs and beta-blockers have real potential to decrease performance-related anxiety and social phobia. They are also fairly safe to use and carry only mild side effects. Benzodiazepines may do the same, but you can get addicted to them. Stay away from the stimulants—too much addiction potential, and they just make you impatient and impulsive. The hallucinogens might have potential for creating new insights and perceptions, but they are, of course, illegal. And finally, the hormone oxytocin seems to function broadly to promote social bonding, which may be a boon for social intelligence.
NOTES
Introduction: Doing What Can’t Be Done
1. Details surrounding Armstrong’s life and death are from Thomas Lewis, Empire of the Air: The Men Who Made Radio (New York: HarperCollins, 1991).
2. Ibid., 254.
One: Through the Eye of An Iconoclast
1. Dale Chihuly, interview with author, Seattle, WA, November 15, 2006.
2. See Sammy Davis Jr., Jane Boyar, and Burt Boyar, Yes I Can: The Story of Sammy Davis, Jr. (New York: Farrar, Straus and Giroux, 1965).
3. See Nancy Etcoff, Survival of the Prettiest: The Science of Beauty (New York: Anchor Books, 1999).
4. See Brian A. Wandell, Foundations of Vision (Sunderland, MA: Sinauer Associates, 1995).
5. See Kristin Koch et al., “How Much the Eye Tells the Brain,” Current Biology 16 (2006): 1428–1434.
6. See G. Kanizsa, “Margini quasi-percettivi in campi con stimolazione omogenea,” Rivista di Psicologia 49, no. 1 (1955): 7–30.
7. See Cindy Gill, “Magnetic Personality,” Pitt Magazine, Fall 2004.
8. See Leila Reddy and Nancy Kanwisher, “Coding of Visual Objects in the Ventral Stream,” Current Opinion in Neurobiology 16 (2006): 408–414.
Two: From Perception to Imagination
1. See Gerald L. Edelman, Neural Darwinism: The Theory of Neuronal Group Selection (New York: Basic Books, 1987).
2. See Neal Gabler, Walt Disney: The Triumph of the American Imagination (New York: Alfred A. Knopf, 2006).
3. For an excellent discussion of the evolutionary theory of perception, as well as many beautiful illustrations of optical illusions, see Dale Purves and R. Beau Lotto, Why We See What We Do: An Empirical Theory of Vision (Sunderland, MA: Sinauer Associates, 2003).
4. See Xiong Jiang et al., “Categorization Training Results in Shape- and Category-Selective Human Neural Plasticity,” Neuron 53 (2007): 891–903.
5. See W. Schultz et al., “Neuronal Activity in Monkey Ventral Striatum Related to the Expectation of Reward,” Journal of Neuroscience 12 (1992): 4595–4610.
6. See Kalanit Grill-Spector, Richard Henson, and Alex Martin, “Repetition and the Brain: Neural Models of Stimulus-Specific Effects,” Trends in Cognitive Sciences 10 (2006): 14–23.
7. See Martha Farah, The Cognitive Neuroscience of Vision (Malden, MA: Blackwell Publishing, 2000).
8. See S. M. Kosslyn et al., “Topographical Representations of Mental Images in Primary Visual Cortex,” Nature 6556 (1995): 496–498; and Xu Cui et al., “Vividness of Mental Imagery: Individual Variability Can Be Measured Objectively,” Vision Research 47 (2007): 474–478.
9. See William James, The Principles of Psychology, vol. 1 (New York: Dover Publications, 1950).
10. See A. C. Nobre et al., “Functional Localization of the System for Visuospatial Attention Using Positron Emission Tomography,” Brain 120 (1997): 515–533.
11. See Farah, The Cognitive Neuroscience of Vision.
12. Sporting News, March 3
, 1948, in Jules Tygiel, Baseball’s Great Experiment: Jackie Robinson and His Legacy (New York: Oxford University Press, 1983).
13. Look, March 19, 1946, cited in Tygiel, Baseball’s Great Experiment.
14. Tygiel, Baseball’s Great Experiment, 52.
15. See David J. Walsh, transcript of interview with Branch Rickey, 1955, ed. Manuscript Division and Branch Rickey Papers, Library of Congress.
16. See Kary B. Mullis, “The Polymerase Chain Reaction,” Nobel Lecture, 1993.
Three: Fear—The Inhibitor of Action
1. See Jackie Robinson and Alfred Duckett, I Never Had It Made (New York: G. P. Putnam’s Sons, 1972).
2. Ibid.
3. Ibid.
4. Ibid.
5. For an excellent explanation of the human stress system, see Robert M. Sapol-sky, Why Zebras Don’t Get Ulcers, 3rd ed. (New York: Owl Books, 2004).
6. Emily Robison, interview on 60 Minutes, May 14, 2006.
7. See Adam Sweeting, “How the Chicks Survived Their Scrap with Bush,” Telegraph, June 15, 2006; and Christoph Dallach and Matthias Matussek, “Let Them Hate Us,” Spiegel Online, July 11, 2006.
8. Natalie Maines, interview on 60 Minutes, May 14, 2006.
9. See Whitney Pastorek, “Heart of Dixie,” EW.com, January 2006.
10. For an excellent review of the amygdala, see Elizabeth A. Phelps and Joseph E. LeDoux, “Contributions of the Amygdala to Emotion Processing: From Animal Models to Human Behavior,” Neuron 48 (2005): 175–187.
11. See Alex Berenson, “A Software Company Runs Out of Tricks; The Past May Haunt Computer Associates,” New York Times, April, 29, 2001; and William M. Bulkeley and Charles Forelle, “Directors’ Probe Ties CA Founder to Massive Fraud; Report Suggests Suing Wang for $500 Million; Evidence of Backdating,” Wall Street Journal, April 14, 2007.
12. See William McCracken and Renato Zambonini, CA, Inc. Special Litigation Committee Report, Chancery Court, Delaware, 2007, 5.
13. Quotes in this section from Jim Lavoie and Joe Marino, interview with author, Newport, RI, June 7, 2007.
14. See Daniel Ellsberg, “Risk, Ambiguity, and the Savage Axioms,” Quarterly Journal of Economics 75 (1961): 643–669.
15. See Ronald C. Kessler, Murray B. Stein, and Patricia Berglund, “Social Phobia Subtypes in the National Comorbidity Study” American Journal of Psychiatry 155, no. 5 (1998): 613–619.
16. See K. N. Ochsner et al., “Rethinking Feelings: An fMRI Study of the Cognitive Regulation of Emotion,” Journal of Cognitive Neuroscience 14 (2002): 1215–1229.
17. See Phelps and LeDoux, “Contributions of the Amygdala,” 175–187.
Four: How Fear Distorts Perception
1. See Presidential Commission on the Space Shuttle Challenger Accident, Report of the Presidential Commission on the Space Shuttle Challenger Accident (Washington, DC: Presidential Commission on the Space Shuttle Challenger Accident, 1986).
2. Ibid.
3. See James Gleick, Genius: The Life and Science of Richard Feynman (New York: Pantheon Books, 1982).
4. Ibid.
5. Ibid., 140.
6. Ibid., 184.
7. See Richard P. Feynman and Ralph Leighton, “Surely, You’re Joking, Mr. Feynman!” Adventures of a Curious Character (New York: W.W. Norton & Company, 1985).
8. Ibid., 134.
9. This section was reconstructed from Asch’s published observations of the experiment and his subjects’ reactions. See Solomon E. Asch, “Effects of Group Pressure upon the Modification and Distortion of Judgments,” in Groups, Leadership and Men: Research in Human Relations, ed. H. S. Guetzkow (Pittsburgh, PA: Carnegie Press, 1951);Solomon E. Asch, Social Psychology (New York: Prentice-Hall, 1952);and Solomon E. Asch, “Studies of Independence and Conformity: I. A Minority of One Against a Unanimous Majority,” Psychological Monographs: General and Applied 70, no. 9 (1956): 1–70.
10. See Gregory S. Berns et al., “Neurobiological Correlates of Social Conformity and Independence During Mental Rotation,” Biological Psychiatry 58 (2005): 245–253.
11. Martin Luther King, Nobel Lecture, December 11, 1964.
12. Ibid.
13. In actuality, the bell-shaped curve will be skewed because the left-hand side is bounded by zero, while the right-hand side is unbounded.
14. See Scott E. Page, The Difference: How the Power of Diversity Creates Better Groups, Firms, Schools, and Societies (Princeton, NJ: Princeton University Press, 2007).
15. James Surowiecki made much of this statistical law and even went as far as suggesting that individual decision making will always be worse than collective decision making, at least when the members of a group act independently of one another. See James Surowiecki, The Wisdom of Crowds: Why the Many Are Smarter Than the Few and How Collective Wisdom Shapes Business, Economics, Societies, and Nations (New York: Doubleday, 2004).
Five: Why the Fear of Failure Makes People Risk Averse
1. Standard & Poor’s Mutual Fund Persistence Scorecard, midyear 2006.
2. The game is called the St. Petersburg paradox because Bernoulli published it in the Papers of the Imperial Academy of Sciences in Petersburg: Daniel Bernoulli, “Exposition of a New Theory on the Measurement of Risk,” Econometrica 22, no. 1 (1738; 1954): 23–36. The paradox was originally formulated by Bernoulli’s cousin, Nicolas Bernoulli, but Daniel gets credit for proposing a solution.
3. John von Neumann and Oskar Morgenstern, The Theory of Games and Economic Behavior, 2nd ed. (Princeton, NJ: Princeton University Press, 1947).
4. Quotes in this section from David Dreman, telephone interview with author October 4, 2006.
5. The steady-state value is 1/(cost of capital). See Michael J. Mauboussin, “M&M on Valuation,” in Mauboussin on Strategy, ed. M. J. Mauboussin (Baltimore: Legg Mason Capital Management, 2005); and Merton H. Miller and Franco Modigliani, “Dividend Policy, Growth, and the Valuation of Shares,” Journal of Business 34, no. 4 (1961): 411–433.
6. See Mauboussin, “M&M on Valuation.”
7. See Kirk Kazanjian, Value Investing with the Masters: Revealing Interviews with 20 Market-Beating Managers Who Have Stood the Test of Time (New York: New York Institute of Finance, 2002).
8. Quoted in Kazanjian, Value Investing with the Masters.
9. See Gregory S. Berns et al., “Neurobiological Substrates of Dread,” Science 312 (2006): 754–758.
10. See Andrew W. Lo and Dmitry V. Repin, “The Psychophysiology of Real-Time Financial Risk Processing,” Journal of Cognitive Neuroscience 14, no. 3 (2002): 323–339.
11. See Andrew W. Lo, Dmitry V. Repin, and Brett N. Steenbarger, “Fear and Greed in Financial Markets: A Clinical Study of Day-Traders,” American Economic Review 95, no. 2 (2005): 352–359.
12. See Henry Ford, My Life and Work (Garden City, NY: Doubleday, Page & Company, 1923).
13. Ibid.
14. Ibid.
15. The DAT gene has two common forms, with either a 9 or a 10 repeat (9R or 10R) of a 40-base pair sequence near its tail end.
16. See Juliana Yacubian et al., “Gene-Gene Interaction Associated with Neural Reward Sensitivity,” Proceedings of the National Academy of Sciences 104, no. 19 (2007): 8125–8130.
Six: Brain Circuits for Social Networking
1. Picasso’s Garçon à la pipe went for $104 million at Sotheby’s in 2004, while Van Gogh’s Portrait of Dr. Gachet sold for $82.5 million at Christie’s in 1990 ($119 million in 2004 dollars).
2. See Malcolm Gladwell, The Tipping Point: How Little Things Can Make a Big Difference (New York: Little, Brown and Company, 2000).
3. For the definitive biography on Stanley Milgram, see Thomas Blass, The Man Who Shocked the World: The Life and Legacy of Stanley Milgram (New York: Basic Books, 2004).
4. Letter to Marilyn Zeitlin, reprinted in Blass, The Man Who Shocked the World, 58.
5. The term was popularized by John Guare in his play Six Degrees of Separation (New York: Random House, 1990).
6. A set of stamped postcard
s was included in the packet, and each person who received it was instructed to put his or her name on a postcard and mail it back to Milgram. In this manner, Milgram was able to track the steps that each packet took on its way to Boston. To prevent a packet from endlessly looping between the same people, Milgram asked each recipient to add their name to a roster that was enclosed as part of the packet, with the additional instruction to send the packet to someone not already on the roster.
7. See Stanley Milgram, “The Small World Problem,” Psychology Today 1 (1967): 61–67; and Jeffery Travers and Stanley Milgram, “An Experimental Study of the Small World Problem,” Sociometry 32, no. 4 (1969): 425–443.
8. Quoted in Eric Schlosser, Fast Food Nation: The Dark Side of the All-American Meal (New York: Perennial, 2002).
9. Ibid.
10. See Nancy Etcoff, Survival of the Prettiest: The Science of Beauty (New York: Anchor Books, 1999).
11. See M. Ida Gobbini and James V. Haxby, “Neural Systems for Recognition of Familiar Faces,” Neuropsychologic 45 (2007): 32–41.
12. See J. P. Mitchell, T. F. Heatherton, and C. N. Macrae, “Distinct Neural Systems Subserve Person and Object Knowledge,” Proceedings of the National Academy of Sciences, U.S.A. 99 (2002): 15238–15243;Chris D. Frith and Uta Frith, “Interacting Minds-A Biological Basis,” Science 286 (1999): 1692–1695; and Truett Allison, Aina Puce, and Gregory McCarthy, “Social Perception from Visual Cues: Role of the STS Region,” Trends in Cognitive Sciences 4, no. 7 (200): 267–278.
13. See D. I. Perrett et al., “Organization and Functions of Cells Responsive to Faces in the Temporal Cortex,” Philosophical Transactions of the Royal Society, London, B 335 (1992): 23–30.