Your Brain on Metaphors

While we were still primates who hadn’t fully developed into human beings, we had no use for, or understanding of, metaphors; but as our brains developed the capacity for language, all that changed. The ability to understand metaphor did not, however, create new brain regions. Rather, the new ability was crammed into existing brain structures concerned with the senses and the physical world.

Consider, for example, the metaphor, “He has a warm personality.” No one literally has a personality with a temperature that’s warmer than someone else’s personality. But the evolving brain put the ability to understand the metaphor into temperature-sensing regions of the brain, resulting in the brain’s occasional confusion between literal and metaphorical.

For example, in a study by Lawrence Williams of the University of Colorado and John Bargh of Yale, a covert experimenter seemed to be struggling with an armful of folders while holding either a cup of hot or iced coffee. The experimenter would ask the research subject to hold the coffee for just a moment while he got a better hold on all his materials. Later, the subject would read the description of a person, and those subjects who had held the warm coffee would rate the described personality as warmer than those subjects who had held the iced coffee.

Another example. A brain structure called the insula senses whether food is rotten or whether something distasteful like a cockroach is being eaten (or even thought about being eaten). In short, the insula registers sensory disgust. Now imagine a disgusting moral situation like an old woman beaten to death by thugs, and the insula activates. Evolution put moral disgust into the same brain region that handles sensory disgust.

Religion, of course, is full of metaphors. We have no direct knowledge of God. So, we compare God to things in our human experience. God is like a father or a king or—more nebulously—like light. God’s love for us is like the motherly love of the Virgin Mary for Jesus; and, in times past, Catholics spoke of Mother Church. Catholics also metaphorically “eat” Christ’s Body and “drink” His Blood although they also want to dissolve the metaphor into real flesh and blood.
Certainly, these religious metaphors activate specific brain regions that were originally “designed” for the physical world of the senses. Although I have no research to support my theory, I imagine that when we associate God with motherliness, the amygdala—a fear-generating structure—is quiescent, and dopamine-rich areas of the brain—like the ventral tegmental area and the caudate nucleus—come alive. (Dopamine is—loosely speaking—the “pleasure molecule.”)

I would suppose that brain regions relating to eating and drinking activate during Holy Communion. After all, communicants do eat the wafer and drink the wine. Likewise, when Quakers experience the Inner Light, does the occipital lobe—primary processor for vision—light up in brain-imaging machines? Or perhaps only the visual associative regions increase their activity?

One thing is sure. We may be spiritual beings, but our spirituality is rooted in our physical bodies and brains.

(This post was inspired by, and partly based on, Dr. Robert Sapolsky’s Teaching Company course, Being Human: Life Lessons from the Frontiers of Science.)

~ Richard Russell