New Under the Sun:
Volume 4, Issue 11
So much for my wish that October would be disaster-free. The earthquake in Pakistan is potentially more devastating than the tsunami because it is more difficult to provide relief to that mountainous region and winter is setting in there. And in the Americas, the hurricane season shows no sign of ending. This year of disasters makes it clear that we can never know what tomorrow will bring. One of the best ways to successfully recover and rebound from disaster is to go into the disaster with optimal health and well-being. Those who are ill or unstable will have much more difficulty recovering. Since we don’t know what the future holds for us, the best plan is to maintain optimal health.
Let’s Sleep On It: The October 27, 2005 issue of Nature has a special section of six articles devoted to understanding sleep. The first article introduces the section by highlighting the main points of the new research: sleep is not a passive state; during sleep neuronal activity undergoes reorganization. J. Allan Hobson. Sleep is of the brain, by the brain and for the brain. Nature 437, 1254-1256 (27 October 2005).
The second article discusses how sleep is regulated and how drugs affect this process. The authors note that sleep is part of a homeostatic system. When the body is deprived of adequate sleep during one sleep period, there is an attempt to recover that lost sleep in subsequent periods. Cognitive decline or poor performance in daily tasks may be related to sleep deprivation. Since the elderly generally sleep less, this may well be something that needs to be considered when one attempts to maintain cognitive abilities. Clifford B. Saper, Thomas E. Scammell and Jun Lu. Hypothalamic regulation of sleep and circadian rhythms. Nature 437, 1257-1263 (27 October 2005).
The third article discusses sleep in a wide variety of mammals. Rodents can die more quickly from sleep deprivation than food deprivation. Sleeping saves energy, so animals with a high metabolism may need to sleep more. However, diet also affects sleep levels. Carnivores sleep the most, omnivores somewhat less, and herbivores sleep the least, with the largest herbivores, such as elephants, needing very little sleep compared to other mammals. Humans are omnivores, so we are in the mid-range of sleep needs. Sleep deprivation may be related to oxidative stress leading to cell damage and may be one reason why sleep deprivation is associated with death. Jerome M. Siegel. Clues to the functions of mammalian sleep. Nature 437, 1264-1271 (27 October 2005).
The fourth article discusses how sleep helps consolidate memories. Their research showed that individuals trained in specific tasks actually improved on those tasks after a good night’s sleep, but did not improve if they were sleep-deprived. It also appears that for these types of tasks, all the various stages of sleep are involved to some degree in memory consolidation. In fact, sleep appears necessary for memory consolidation to occur since those trained early during the day and then tested later on that day showed no signs of improvement. In an interesting test, subjects were taught a difficult method for solving a mathematical problem without being informed that there was a simpler method. When they were retested after 12 hours, a few individuals had figured out the simpler method. The odds that they would do this were more than doubled if they’d had a night’s sleep prior to retesting. This would support the idea that creative insights often arise after a good night’s sleep. Robert Stickgold. Sleep-dependent memory consolidation. Nature 437, 1272-1278 (27 October 2005).
In the fifth article, sleep disorders are discussed. The disorder with major societal consequences is hypersomnia: excessive daytime sleepiness. This disorder is involved in at least 100,000 vehicle crashes each year, and major disasters such as Three Mile Island and the Exxon Valdez. “…we get 20% less sleep than previous generations, and there is no evidence that earlier generations required more sleep, or that ours needs less.” [p. 1279] Other disorders the article discusses include: insomnia, biological clock/societal expectations mismatch, and parasomnias, which include sleep walking and night terrors. Mark W. Mahowald and Carlos H. Schenck. Insights from studying human sleep disorders. Nature 437, 1279-1285 (27 October 2005).
The sixth article deals with dreaming. Although the source for dream imagery is unclear, dreams tend to occur in the “here and now”. This may be because our brains are organized this way even in sleep. The source for dream imagery may come from past experiences that have recently been re-triggered. The imagery may be strange and hard to interpret, but the emotional content of the dream may relate to current events. In short, we are still not sure what dreams mean. Tore A. Nielsen and Philippe Stenstrom. What are the memory sources of dreaming? Nature 437, 1286-1289 (27 October 2005).
Book Review: Continuing our theme of psychological and physical health, this month’s book review is of Our Inner Ape by Frans de Waal. De Waal has written several previous books on primate behavior, all of which are well-worth reading. For those who’ve read his previous books, there will be some familiar material here. But for those who’ve not yet had the pleasure, this book makes a suitable introduction to de Waal’s work since it presents the most up-to-date information on our primate relatives, particularly chimpanzees/bonobos. [Parenthetical insertion: I am one of a possibly tiny minority who consider bonobos to be just a sub-population of chimpanzees, not a different species. My reason for this is that a male from one population and a female from the other can produce viable, fertile offspring. This is the definition of species devised by Ernst Mayr, one of the major biologists of the 20th century.]
To fully understand human behavior we need to be able to compare different behaviors not only cross-culturally among differing human groups, but cross-species among our nearest primate relatives. Analyzing such studies allows us to determine the normal range of variation of a trait/behavior and it evolutionary origins. De Waal begins the book with a chapter on why apes are a good comparative group for humans. He then moves into the meat of the book with four chapters devoted to the major themes affecting our lives: power, sex, violence, and kindness. He concludes the book with a chapter on how humans, as bipolar apes, have the ability, if they choose to use it (far out-stripping our ape relatives) to create societies that achieve a harmonious balance among conflicting tendencies such as helping or hating someone outside one’s own group. Reducing conflict reduces stress and leads to a longer, healthier life.
Once you are aware of how chimps manage power struggles, it is easy to see the same thing occurring in human interactions. Men suppress emotion and resist doctor visits because these can be seen by rivals as signs of weakness that can be exploited. Men pick fights to determine their position in the status hierarchy. The result is that men have high levels of stress and are more likely to engage in behaviors that result in premature death. Women smile more than men as a sign of appeasement. But analysis of bonobo society shows that other ways are possible. Male bonobos live in a more egalitarian society where females form bonds that allow them to control a power-hungry male. Male bonobos are able to live out their two score and five in relative harmony and peace.
The primary stress-reliever among bonobos is sex. Any time an individual feels stressed or expects a situation might become stressful, he or she seeks out a sex partner. This could be literally anyone in the group. After a little sex, stress is alleviated, and life goes on peacefully. Bonobos should give us pause when we view homosexuality and heterosexuality as dichotomous positions instead of points on a sexual continuum. Attempts to control or repress sexuality among humans has created societal conflict, even wars. Free expression among bonobos results in relative peace. We don’t need to go to the bonobo end of the sexual continuum to realize that society would benefit from refocusing our energies from attempts to control the sexual behavior of consenting adults to something more pertinent such as avoiding ecological disaster.
Wars are fought over access to scarce resources, generally food and/or females. This is true of humans and other primates. One reason bonobos do not fight other groups is that they live in a resource-rich environment with free access to females by males. Other chimp groups occasionally fight fierce battles because there is more competition for resources. There are some monkey species that, despite full access to resources, are still quite belligerent. De Waal and others have done some interesting experiments involving cross-fostering of monkey species. They’ve found that monkeys who are biologically from aggressive species but who are raised from infancy, or even in utero, by females from pacifist species will also be pacifist. In another study, when the most aggressive males in one wild baboon troop were killed when they accidentally ate diseased meat, the troop became peaceful and maintained this pacifism for at least two generations, probably through the influence of the females who stay in their natal troop. The conclusion is that violence can be socially diffused.
Touch helps diffuse stress and can decrease violence. Touch is vital to healthy development. Infants deprived of touch die. Giving your neighbor a hand builds bonds. Touch, via grooming, forms the glue of primate societies. When an individual in distress is touched, we know that empathy is present. Empathy is the basis of morality. De Waal has written an entire book on the evolutionary basis of morality, Good Natured, which I also recommend reading. A sense of fairness and justice is also necessary and these have been demonstrated in many studies involving apes and monkeys. Kindness and caring are readily extended to those we perceive as in our group. The trick is to expand the definition of “our group.” The more inclusive it is, the more harmonious society will be. This is where empathy is important. When we can put ourselves into someone else’s position, it becomes harder to treat them unfairly.
De Waal views our bipolar nature as a good thing because harmony is achieved by balancing opposing forces. We are capable of more brutality than chimps, but more kindness than bonobos. We view ourselves as the most rational of animals, but we make most of our decisions emotionally. We are selfish, but need others to feel whole. De Waal concludes by discussing the type of society for which we are best adapted. This society should be as egalitarian as possible, certainly there should not be gross economic inequities. Urban regions should be organized into small, relatively self-sufficient communities. Communism fails because it ignores the needs of the individual. Un-checked capitalism will fail because it ignores the needs of the majority. According to de Waal, the United States is already seeing the results of an unbalanced economic system. Of all the major industrial nations, the US has one of the worst health records. Life expectancy is below that of the top 25 nations. Northern Europeans are on average three inches taller than Americans, an indication of good diet and good health care. Economically, the US has an income disparity more in line with third world than first world nations with the top one percent having more income than the entire bottom 40 percent. If we do not care about our own, how can we care about others?
Finally, de Waal says a human: “It is capable of unbelievable destruction of both its environment and its own kind, yet at the same time it possesses wells of empathy and love deeper than ever seen before. Since this animal has gained dominance over all others, it’s all the more important that it takes an honest look in the mirror, so that it knows both the archenemy it faces and the ally that stands ready to help it build a better world.” [p. 237]
AnthroHealth Tip of the Month: Life is busy and stressful. In order to operate at peak efficiency, make sure you get plenty of sleep. Adequate sleep improves cognitive functioning and allows cells time to repair. The article on sleep disorders includes the following information to determine how much sleep you need.
§ The total sleep
requirement is genetically determined on an individual basis.
© 2001-2009 Kathleen E. Fuller, PhD. All rights reserved.