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Although formulas have greatly improved over the years, no formula can fully replicate the immunological benefits of mother’s milk.
“For every organ, there is a critical period, often very brief, when it goes through development,”
“It happens for different organs at different times. After birth only the liver and the brain and the immune system remain plastic. Everything else is done.”
PAIN IS A strange and troublesome thing. Nothing in your life is more necessary and less welcome.
Pain is full of paradoxes.
Exactly how pain works is, as you will gather, still largely a mystery.
Perhaps the weirdest irony of all is that the brain has no pain receptors itself, yet it is where all pain is felt.
“an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage,”
Nociceptors respond to three kinds of painful stimuli: thermal, chemical, and mechanical, or at least so it is universally assumed.
The swift A delta fibers give you the sharp ouch of a hammer blow; the slower C fibers give you the throbbing pain that follows.
Even so, as an aid to responding quickly, we have reflexes, which means that the central nervous system can intercept a signal and act on it before passing it on to the brain.
The spinal cord, in short, is not just a length of impassive cabling carrying messages between the body and the brain but an active and literally decisive part of your sensory apparatus.
That’s why spicy foods taste hot, for instance. They chemically activate the same nociceptors in your mouth that respond thermally to real heat. Your tongue can’t tell the difference.
The person who first identified nociceptors—who can indeed fairly be called patriarch of the central nervous system altogether—was Charles Scott Sherrington (1857–1952), one of the greatest and most inexplicably forgotten British scientists of the modern era.
He proposed the law of reciprocal innervation for muscles, which states that when one muscle contracts, a companion muscle must relax—essentially explaining how muscles work.
While studying the brain, he developed the concept of the synapse, coining the term “synapse” in the process. This in turn led to the idea of proprioception—another Sherrington coinage—which is the body’s ability to know its own orientation in space.
The central nervous system is the brain and spinal cord.
The nerves radiating out from this central hub—the ones that reach out to the other parts of your body—are the peripheral nervous system.
The nervous system is additionally divided by function into the somatic nervous system, which is the part that controls voluntary actions (like scratching your head), and the autonomic nervous system, which controls all those things like heartbe...
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The autonomic nervous system is further divided into sympathetic and pa...
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The sympathetic is the part that responds when the body needs sudden actions—what is generally referred to a...
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“rest and digest” or “feed...
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An oddity of human nerves is that those in the peripheral nervous system can heal and regrow when damaged, whereas the more vital ones in the brain and spinal cord cannot.
The most common category is nociceptive pain, which simply means stimulated pain.
A second type is inflammatory pain, for when tissue becomes swollen and red.
A third category is dysfunctional pain, which is pain without external stimulus and that causes no nerve damage or inflammation.
A fourth kind of pain is neuropathic pain, in which nerves are damaged or grow sensitive, sometimes as a result of trauma...
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When pains don’t go away, pain goes from being a...
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Wall singled out cancer pain as “the apogee of pointlessness.” Most cancers don’t cause pain in their early stages when it might usefully alert us to take remedial action. Instead, all too often cancer pain becomes evident only when it is too late to be useful.
“Patrick Wall was in an era when people kept trying to hypothesize a purpose for chronic pain,” she says.
But chronic pain has no purpose. It’s just a system gone wrong, in the same way that cancer is a system gone wrong.
“But when nerves are damaged, they do exactly the opposite—they switch on. Sometimes they just won’t switch off, and that is when you get chronic pain.”
Generally, we don’t feel pain in most of our internal organs. Any pain that arises from them is known as referred pain because it is “referred” to another part of the body.
The brain is also without feelings, which raises the natural question of where do headaches come from? The answer is that the scalp, the face, and the other outer parts of the head all have plenty of nerve endings—more than enough to account for most headaches.
You would think that if any condition is universal, it is the headache, but 4 percent of people say they have never had one.
Migraines are almost wholly a mystery. They are highly individual.
Pain is curiously mutable. It can be increased, attenuated, or even ignored by the brain depending on the situation. In extreme circumstances, it may not register at all.
By one estimate, about 60 percent of all infectious diseases are zoonotic (that is, from animals).
The particular tragedy of it is that she could have spared her unfortunate victims if she had just washed her hands before handling food.
Smallpox is almost certainly the most devastating disease in the history of humankind.
Smallpox only infects humans, and that proved to be its fatal weakness.
When talking of diseases, people often use “infectious” and “contagious” interchangeably, but there is a difference. An infectious disease is one caused by a microbe; a contagious disease is one transmitted by contact.
“The early history of cancer is that there is very little early history of cancer.”
Today some 40 percent of us will discover we have cancer at some point in our lives. Many, many more will have it without knowing it and will die of something else first.
fact, cancer is entirely internal, a case of the body turning on itself.
What it comes down to really is cancer is, appallingly, your own body doing its best to kill you. It is suicide without permission.
It is only when tumors grow big enough to press on nerves or form a lump that we become aware that something is wrong. Some cancers can quietly accrete for decades before they become evident. Others never become evident at all.
Even when seemingly defeated, it may leave behind “sleeper” cells that can lie dormant for years before springing to life again.
“They have evolved to avoid detection,” says Vormoor. “They can hide from drugs. They can develop resistance. They can recruit other cells to help them. They can go into hibernation and wait for better conditions. They can do any number of things that make it hard for us to kill them.”
We need to remind ourselves from time to time that these are brainless cells we are considering here.
