CHAPTER FIVE
The immune system has also surprised scientists by its ability to learn. Dr. Robert Ader, one of the founders of the field of psychoneuroimmunology, discovered that the immune system can be trained in the very same way that Pavlov trained dogs to salivate at the sound of a bell. The dogs were given meat powder, which caused them to salivate. But if Pavlov paired the presentation of the meat powder with the ringing of the bell, soon the animals salivated to the sound of the bell alone. This is called classical conditioning.
Ader and his colleague, immunologist Nicholas Cohen, showed that if rats were given an immunosuppressive drug accompanied by apple juice, later on the rats would immunosuppress just by tasting the juice. Rats could also be exposed to drugs that enhanced different aspects of the immune system, and the immunoenhancement could be similarly trained.
Let's speculate on the possible implications of such conditioned learning. Perhaps a boss, an ex-spouse, or some situation is or has been a significant source of pain or chronic stress for you. When any cue associated with the situation comes up, your neuropeptides and autonomic nervous system go into a distress mode. The fact that it is easy to condition the immune system is a very practical reason to practice forgiveness so that we can leave old stresses in the past instead of reacting to them for a lifetime. In the same vein, since, as we shall see, feelings of joy and connectedness may enhance immune function, pictures of our loved ones, beautiful views, or forgiving thoughts may keep our immune system functioning optimally.
Miron and I had the great pleasure of working for several years with one of the most interesting psychologists of our time, Dr. David McClelland. McClelland, who spent most of his academic years as a professor of psychology at Harvard, is well known for his research on human motivation. Some people, he found, are highly motivated to achieve. If you present them with a set of pictures and ask them to write stories about what they see, you can get a spontaneous sample of their thinking—of the images in their minds. Such individuals have a lot of thoughts about solving problems, winning, coming out ahead, and getting things done. Other people are motivated by the need for power. These people write stories about dominating situations and other individuals, even though they may be in helping roles.
McClelland has done fascinating research linking the images that arise from our basic motivations, which are really our most deeply held values, and the function of our immune system. One of his most intriguing studies concerns the motive for unconditional love. When McClelland is trying to arouse thoughts related to a specific motive in a laboratory setting, he often uses films. A film about the Third Reich, for example, will generally increase power motivation. Finding a film that might bring out the love motive, however, has been a very challenging task.
Romantic love stories are a decidedly mixed bag. They may involve not only love, but also loss. And even if the love is uncomplicated in the movie, it might still tap into romantic problems in the viewer's own life. So, what's a researcher to do? McClelland settled on the idea of using a documentary on Mother Teresa. His student research assistants were opposed at first, on the grounds that the Harvard students who were to be research subjects might not have positive feelings toward Mother Teresa. In fact, some Harvard students had walked out on a commencement address she had given in the 1980s because they disagreed with her strong anti-abortion stance. McClelland was unconcerned about this problem, though. He believed that regardless of whether the students' conscious minds liked Mother Teresa or not, their unconscious minds could not help but respond to the power of her love.
Professor McClelland decided to use a very simple measure of immunity—the secretion rate of an antibody called sIgA in saliva. Like the palace guard, sIgA protects the gates of our body from invasion by bacteria, viruses, and parasites. Deficiencies of sIgA due to intense stress, such as that of a foot soldier in a foxhole or trench, allow a bacterial proliferation in the gums known as necrotizing gingivitis—or more aptly—trench mouth. Low levels of sIgA would also correlate with more tooth decay and upper respiratory tract infections, such as colds and flu.
Students were asked to spit into test tubes before and after watching Mother Teresa. They also wrote stories in response to a standard set of pictures so that Professor McClelland could get a sample of their thoughts and images with which to score their motives. Sure enough, the film increased both thoughts of unconditional love and the secretion rate of sIgA.
Love, as we discussed in the previous chapter, is a matter of connectedness. In a study that Miron and I did in collaboration with Professor McClelland and one of his former students, Dr. John Jemmott—whose thesis project this was—we found that students whose primary motive was friendship had higher levels of sIgA than those whose primary motive was power. Furthermore, the power-motivated students had dramatic declines in sIgA during exam periods, while those whose primary motive was friendship had much higher levels of sIgA during exams. Friendship, as the studies on the health benefits of social support imply, is good for your health!
Perhaps you've personally experienced feeling better after talking to someone who can understand, through their own experience, what you are going through. Every once in a while I get overtired from traveling and feel like a marathoner who has hit the wall. Although most of my friends can appreciate my feelings of fatigue and empathize with the fact that I'm sick of talking and ready to have a long, solitary rest, I always feel better if I can talk to my friend Loretta, who also travels around the country presenting lectures and workshops. We can exchange funny stories about life on the road from the shared perspective of two women, make plans for how to manage our schedules better, commiserate about our wrinkles, encourage one another's successes, and soothe each other's wounds. By the time I hang up from our conversation, I no longer feel alone. If she can do this, so can I! Even my lymphocytes feel relieved.
