The Doctor Weighs In

By Dov Michaeli MD, Ph.D

I vividly remember a conversation I had with a London cab driver just before the election that unseated John Major (Conservative party) and elected Tony Blair (Labor party). I asked him who he was going to vote for, fully expecting him to make a “rational” decision and vote his economic interests. But, to my astonishment, he was going to vote for the conservatives. Why? I asked in disbelief. The answer was shocking to me. I’ll paraphrase: “because we working class blokes should know our place. The Aristocrats have been running this country forever, and they have done a bloody good job at it. And every time labor got its hands on power they made a bloody mess”.

This episode was etched in my memory, so incredible and yet so profound it was. How to explain such reverence to social hierarchy? Is it a product of generations of social brainwashing? Shakespeare, himself not an aristocrat or even a minor noble, portayed with great disdain characters of low social standing who tried to reach beyond their class. But is it really just a function of culture? Did anything change in the USSR after the revolution, when all classes were abolished with the stroke of a pen (and a bullet, for added emphasis)? Definitely not. The peasant still “knew his place”, only the superior feudal, properly addressed as “gospodin”( sir, master) was replaced by a newly minted commissar, addressed as “tovarish” (comrade).

So if it’s not purely socio-cultural, what is it?

It’s all in your head

A wonderful paper was published in the latest issue of Neuron, the neurobiology magazine. It was authored by Caroline Zink, Ph.D., Andreas Meyer-Lindenberg, M.D., Ph.D., and colleagues of the NIMH Genes Cognition and Psychosis Program.

Prior studies have shown that social status strongly predicts health. Animals chronically stressed by their hierarchical position have high rates of cardiovascular and depression/anxiety-like syndromes. A classic study of British civil servants found that the lower one ranked, the higher the odds for developing cardiovascular disease and dying early. Lower social rank likely compromises health through psychological effects, such as by limiting control over one's life and interactions with others. However, in hierarchies that allow for more upward mobility, those at the top who stand to lose their positions can have higher risk for stress-related illness. Yet little is known about how the human brain translates such factors into health risk.

To find out, the NIMH researchers created an artificial social hierarchy in which 72 participants played an interactive computer game for money. They were assigned a status that they were told was based on their playing skill. In fact, the game outcomes were predetermined and the other "players" simulated by computer. While their brain activity was monitored by fMRI, participants intermittently saw pictures and scores of an inferior and a superior "player" they thought were simultaneously playing in other rooms.

Although they knew the perceived players' scores would not affect their own outcomes or reward -- and were instructed to ignore them -- participants' brain activity and behavior were highly influenced by their position in the implied hierarchy.

What did they find?

Key study findings included:

 The area that signals an event's importance, called the ventral striatum, responded to the prospect of a rise or fall in rank as much as it did to the monetary reward, confirming the high value accorded social status.

•  Just viewing a superior human "player," as opposed to a perceived inferior one or a computer, activated an area near the front of the brain that appears to size people up -- making interpersonal judgments and assessing social status. A circuit involving the mid-front part of the brain that processes the intentions and motives of others and emotion processing areas deep in the brain activated when the hierarchy became unstable, allowing for upward and downward mobility.
•  Performing better than the superior "player" activated areas higher and toward the front of the brain controlling action planning (prefrontal cortex), while performing worse than an inferior "player" activated areas lower in the brain associated with emotional pain and frustration (amygdala).
•  The more positive the mood experienced by participants while at the top of an unstable hierarchy, the stronger was activity in this emotional pain circuitry when they viewed an outcome that threatened to move them down in status. In other words, people who felt more joy when they won also felt more pain when they lost.

Surprise?

These findings are actually not very surprising. Anybody who ever observed monkeys and apes in their natural habitat could easily pick out the alpha male and female, and the submissive behavior of the rest of rest of the clan. But a more detailed observation reveals subtle gradations in social standing among the “lower class” members. Each member of the clan ”knew his or her place”, and acted accordingly. Furthermore, violations of the boundaries of social standing were promptly punished. Is it surprising then that a specific area in the brain, called the striatum, is dedicated to assessing one’s place in a group? Furthermore, it is located right behind the prefrontal cortex, the area that is making rational decisions based on the inputs that reach it from all areas of the brain. The proximity of the striatum to the prefrontal cortex reduces the time for a message to reach the decision-making circuits--a biological testament to the importance ascribed to social animals “knowing their place” in their society.

The experiment showing that in unstable hierarchies people at the top are just as anxious and stressed as people at the bottom is truly revealing. What is the societal equivalent to “unstable hierarchies”? Democracy, of course. Today you are on top, but your position there is constantly challenged, and eventually you have to give up your exalted position. Anybody who observed our presidents at the beginning of their term, and at the end, couldn’t fail but notice how much they aged. Even a clueless president like George W has aged noticeably.

What is truly remarkable in this study is the documentation of the existence of the ‘social brain’. It has long been hypothesized that areas in the brain are specializing in directing social interactions like emulation, attunement, empathy and altruism. This study provides unequivocal neuro-anatomical proof.

Here's a note from a reader:

"Hi Pat-

I am still awed by the heroic stories of Wesley Autrey and Sergeant Tommy Rieman, both of whom were honored by the President during his State of the Union address. This is a level of altruistic behavior that far surpasses the one exhibited by social insects.

In insect society, altruism is enforced, and deviation from the altruistic norm is punished. A worker bee has perfectly functional ovaries-but will refrain from laying eggs and will devote her life to foraging, for the good of the community. Eggs laid by the occasional rebellious worker will be simply eaten by other members of the community-so, what’s the point? She might as well obey the rules. Yes, a bee will also sacrifice her life in defense of the hive by stinging the aggressor and leaving the sting in his body-and die. This behavior, however, not volitional-it is totally automatic, fueled by nerves, hormones, and pheromones.

The evolutionary roots of altruistic behavior .

Obviously, we can only speculate on ‘how did it all start?’; what is the biological matrix that allowed this phenomenon to take shape and come to its ultimate expression in a soldier shielding his buddy from machine gun fire with his own body?

My own pet theory is that it all started with cooperation, and that is a truly ancient trait of living organisms. There is suggestive much evidence that the beginning of life on earth was in the form of unicellular organisms swimming in a primordial soup. Most likely individual cells bumped into each other quite randomly, and stayed stuck together by virtue of their oily, lipid membranes. As the number of cells in this agglomeration increased, different cells found themselves in different environments. Some where located in the interior, others in the outer layer, and still others in between.

These shapeless, ‘dumb’ blobs could have lived happily ever after if not one, or several, of them began to have cells that performed some functions better than their neighbors, while other functions were performed better by the neighbors. For example, it is quite plausible that some outer cells that possessed flagella (little whips) or cilia (little hairy projections) were better at swimming or collecting more food by beating and directing the surrounding soup to the interior of the agglomerated mass. And if some cells in the interior had a somewhat better capacity to take in the soup, filter it and retain some nourishing substances, and maybe somewhat later ‘learn’ how to digest them-then we have division of labor, and this is not a shapeless mass of cells anymore-it is a colony. Or a society, If you will.

As division of labor advanced and specialization deepened, cells became less and less ‘individualistic’ so to speak, looking after their own interests, and more and more ‘selfless’. Of course, I am anthropomorphizing here, but it makes the point. In this environment, it does not take a great stretch of the imagination to speculate that some cells would specialize to sacrifice themselves for the good of the colony. Is there any evidence for this wild speculation?

Those amazing neutrophils .

When we are invaded by microbes (and we are indeed constantly under attack), our first line of defense are white blood cells, called neutrophils.

They will engulf, swallow and kill the invaders, and normally will die within 24 hours after performing this life saving act. Coming to think of it, this has the ring of altruistic behavior to it. But there is more.

Arturo Zychlinsky and his colleagues from the Max Planck Institute in Berlin have published a fascinating report in the January 22 issue of the Journal of Cell Biology (Fuchs et al, J. Cell Biol. Vol.176, pp. 231-241, 2007). They describe a newly discovered mechanism of neutrophilic defense; I would call it the Samson Defense. This playboy of the Eastern world was blinded and tortured by the Philistines, but rather than endure the indignity, he used his great physical strength to bring down the temple upon himself and his tormentors. The neutrophils do the same.

While many of the neutrophils simply perform their duty in the conventional way by engulfing and internalizing the invaders, others, for unknown reason, commit suicide and take the invading hordes with them.

How do they do it?

Fuchs and his colleagues observed that the process begins by the breakup of the nuclear membrane. Once this is accomplished, the nuclear chromatin (the material that makes up the chromosomes, DNA and its protein coating) leaks out into the cytoplasm. While this is happening, the membranes that surround granules that reside in the cytoplasm disintegrate as well. These granules are deadly to microbes-they are made up of enzymes that wreak havoc with their structure, and kill them. The chromatin now binds with the granules and together they organize themselves into a mesh, or network.

Finally, the neutrophil’s cell membrane disintegrates and the mesh gets outside the cell, or more accurately-the ghost of the cell, since it had died when all its internal structure disintegrated. But the mesh serves as a trap for the microbes. Once they get enmeshed in the sticky net, the deadly enzymes of the granules finish the job.

Final Thoughts .

So there you have it. A cell sacrificing itself, with no benefit for itself, for the good of the ‘society’ of cells that make up the organism. It keeps fighting the invading microbes after it has long died. And it doesn’t even get a silver medal or a purple heart for this heroic feat.

Just think of it: here is an unbroken, albeit mechanistically ever more complex, line of courageous and selfless behavior that started in some lowly cells close to a billion years ago, became part of us hundreds of thousands years ago, and somehow led to the heroic sergeant--fascinating, and awe inspiring.