pyramidal neurons in mouse cerebral cortex expressing green fluorescent protein

We often compare the human body to a machine. That metaphor is a product of the Industrial Age. Food becomes fuel, your digestive system is a kind of engine and so on. In this Information Age, we often compare our brain to a computer – memory, storage, files not found and so on.

We have also compared the way the brain makes decisions to forms of government for a much longer time. If you use that metaphor, then you have to ask if our brain is a democracy or dictatorship, or some form not as familiar to us.

The democracy or dictatorship of the brain is the topic of an article by Ari Berkowitz. He tells us that back in 1890, psychologist William James argued that in each of us “[t]here is… one central or pontifical [nerve cell] to which our consciousness is attached.” Then, in 1941, Sir Charles Sherrington argued against the idea of a single pontifical cell in charge. He suggested that the nervous system is “a million-fold democracy whose each unit is a cell.”

Berkowitz has a book, Governing Behavior, that covers experiments on “decision-making architectures in nervous systems” and they show forms from dictatorship, to oligarchy, to democracy. Yes, a single “dictator neuron” can take charge of complex behaviors, but not in all cases.

But there is always a danger in using and extending metaphors.

To answer the question of which form is most like our brain, you need to accept that the brain is not like the countries that cover our planet. Perhaps, our brain should be compared to Earth with multiple forms of government (or architectures) simultaneously, rather than to one country/government. Thank goodness we have some dictatorships in that gray matter that can act quickly without consulting others or (and this would be frightening) forming a committee to consider all the possibilities.

Many studies have been done on non-human brains, and it is also dangerous to extrapolate what happens in a monkey or mouse brain to our own. But that’s what scientists do, often out of necessity.  So, we know that more “democratic” circuits, such as the ones that control eye movements in monkeys, are compared to decisions determined by a tally of “votes” from a large “population” of neurons.

Nervous systems are not restricted to using one set of procedures at a time. Evolution allows them to use whichever ways are most effective and combine multiple forms of “government simultaneously.” I’m not sure we would say that the governments of the Earth have been able to operate with multiple governments in a similar harmony.

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