—Woody Allen Yesterday Joan tripped on a step. She didn’t suspect that she’d injured herself—but today she has just become aware of a terrible pain in her knee. She’s been working on an important report and tomorrow she plans to deliver it. “But if this keeps up,” she hears herself think, “I won’t be able to take that trip.” She tries to make herself get back to work, but shortly she drops her pen and moans, “I really must get rid of this pain.” She attempts to visit her medicine shelf, to find a pill that could bring some help, but a stab of pain makes her sit back down, and instructs her not to use that leg. She clutches her knee, catches her breath, and tries to think about what to do next—but the pain so overwhelms her mind that she can’t seem to focus on anything else.
How does Joan know where her pain is located? That’s easy to do for each place on her skin—because she is born with ‘maps’ of her skin in various different parts of her brain, like this one in the sensory cortex.
www.sm.luth.se/.../ Sensory%20homunculus.png
Many textbooks about the brain explain that those maps help us to determine the locations of tactile sensations—but those books don’t ask what advantage we gain from having those maps—considering that the skin itself could serve for that. (We’ll discuss this in TopoQualia.) However, we are not nearly so good at locating the causes of interior pains. It seems that our brains do not come equipped to represent the locations of structures inside our skins. Presumably, good maps for these have never evolved because they would not have been of much use to us: before the era of medicine, there was no way to protect one’s spleen, except to guard one’s whole abdomen—hence all one actually needed to know is when one had a bellyache. In particular, one never says, “I feel a terrible pain in my brain,” because we never had any remedies for injuries to the brain itself—so we never evolved any sense of pain in our brains, or of the spatial locations of mental events.
In any case, for Joan’s pain to be useful to her, it must make her focus her thoughts on that knee—while also postponing her other goals. “Get rid of Me,” Joan’s pain demands, “and get back into your Normal State.” She won’t be able to work on her report until she can satisfy that imperative.
How does our sense of pain actually work? Our scientists know quite a lot about the very first few events that result when a part of your body is traumatized. First, the injured cells release chemicals that cause a special type of nerve to send signals to your spinal cord. Then certain neural networks send other signals up to your brain. However, our scientists understand much less of what happens, then, in the rest of the brain. In particular, I’ve never seen any good high-level theories of how or why pain leads to suffering. Instead we find mainly descriptions like this:
The sense of pain originates when special nerves react to high temperature, pressure, etc. Then their signals rise up to your thalamus, which sends them to other parts of your brain—in ways that on various ways involve hormones, endorphins, and neurotransmitters. Eventually, when some of those signals reach your limbic system, this results in such emotions such as sadness, anger, and frustration.
However, that doesn’t explain what suffering is—because it isn’t enough only to know which parts of the brain are involved with pain. We must also know what those parts do and how each affects the other ones, both when we’re in our most usual states and (to make sense of suffering) when we’re subject to larger cascades. Ronald Melzack and Patrick Wall, who pioneered theories of how pain works, cautiously note that:
“An area within the functionally complex anterior cingulate cortex has a highly selective role in pain processing, consistent with an involvement in the characteristic emotional/motivational component (unpleasantness and urgency) of pain.[33]
But we also know that that pain is involved with many other parts of the brain.[34] Thus Melzack and Wall go on to say,
“The concept [of a pain center] is pure fiction unless virtually the whole brain is considered to be the ‘pain center’ because the thalamus, the limbic system, the hypothalamus, the brain stem reticular formation, the parietal cortex, and the frontal cortex are all implicated in pain perception.”
Furthermore, our reactions to pain depend on other mental conditions:
Daniel Dennett: “Real pain is bound up with the struggle to survive, with the real prospect of death, with the afflictions of our soft and fragile and warm flesh. ... There can be no denying (though many have ignored it) that our concept of pain is inextricably bound up with (which may mean something less strong than essentially connected with) our ethical intuitions, our senses of suffering, obligation, and evil.”[35]
In general, we still do not know much about how physical pain leads to suffering. For although we have learned a good deal about where many functions are done in the brain, we still know very little about how each of those brain-parts actually work—because we still need theories (like those in this book) about what those resources actually do.
Perhaps we’ll find more clues about such things in a rare condition that results from injuring certain parts of the brain: the victims of ‘Pain Asymbolia’ still recognize what the rest of us describe as pain—but do not find those feelings unpleasant, and may even laugh in response to them. Perhaps they have lost some resources that cause what, in others, are cascades of torments.
??????????????????? Physical vs. Mental ‘Pain’
Citizen: Physical pain is just one kind of pain—and emotional pains can be just as intense; they can even drive people to suicide. How could your theory also explain those other kinds of agonies?
Are mental and physical pains the same? They frequently seem to have similar ways to make changes in our mental states. What kind of relation could there be between how we react to, say, pinching or burning of the skin, and ‘painful’ events inside our minds, like,
The pain of losing a long-term companion.
The pain of watching the pain of others.
The pain of sleep deprivation.
The pain of humiliation and perceived failure.
The pain of excessive and prolonged stress.
Suppose that you were to hear Charles say, “I felt so anxious and upset that it felt like something was tearing my gut.” You might conclude that Charles’s feelings reminded him of times when he had a stomachache.
