Steve Silberman (@stevesilberman on Twitter) is a journalist whose articles and interviews have appeared in Wired, Nature, The New Yorker, and other national publications; have been featured on The Colbert Report; and have been nominated for National Magazine Awards and included in many anthologies. Steve is currently working on a book on autism and neurodiversity called NeuroTribes: Thinking Smarter About People Who Think Differently (Avery Books 2013). This post originally appeared on his blog, NeuroTribes.
Photo by Flickr user Noodles and Beef
Your doctor doesn’t like what’s going on with your blood pressure. You’ve been taking medication for it, but he wants to put you on a new drug, and you’re fine with that. Then he leans in close and says in his most reassuring, man-to-man voice, “I should tell you that a small number of my patients have experienced some minor sexual dysfunction on this drug. It’s nothing to be ashamed of, and the good news is that this side effect is totally reversible. If you have any ‘issues’ in the bedroom, don’t hesitate to call, and we’ll switch you to another type of drug called an ACE inhibitor.” OK, you say, you’ll keep that in mind.
Three months later, your spouse is on edge. She wants to know if there’s anything she can “do” (wink, wink) to reignite the spark in your marriage. She’s been checking out websites advertising romantic getaways. No, no, you reassure her, it’s not you! It’s that new drug the doctor put me on, and I hate it. When you finally make the call, your doctor switches you over to a widely prescribed ACE inhibitor called Ramipril.
“Now, Ramipril is just a great drug,” he tells you, “but a very few patients who react badly to it find they develop a persistent cough…” Your throat starts to itch even before you fetch the new prescription. Later in the week, you’re telling your buddy at the office that you “must have swallowed wrong” — for the second day in a row. When you type the words ACE inhibitor cough into Google, the text string auto-completes, because so many other people have run the same search, desperately sucking on herbal lozenges between breathless sips of water.
In other words, you’re doomed. Cough, cough!
Vaughan Bell is a clinical and research psychologist based at the Institute of Psychiatry, King’s College London and currently working in Colombia. He’s also working on a book about hallucinations due to be out in 2013.
During surgery, a patient awakes but is unable to move. She sees people dressed in green who talk in strange slowed-down voices. There seem to be tombstones nearby and she assumes she is at her own funeral. Slipping back into oblivion, she awakes later in her hospital bed, troubled by her frightening experiences.
These are genuine memories from a patient who regained awareness during an operation. Her experiences are clearly a distorted version of reality but crucially, none of the medical team was able to tell she was conscious.
This is because medical tests for consciousness are based on your behavior. Essentially, someone talks to you or prods you, and if you don’t respond, you’re assumed to be out cold. Consciousness, however, is not defined as a behavioral response but as a mental experience. If I were completely paralyzed, I could still be conscious and I could still experience the world, even if I was unable to communicate this to anyone else.
This is obviously a pressing medical problem. Doctors don’t want people to regain awareness during surgery because the experiences may be frightening and even traumatic. But on a purely scientific level, these fine-grained alterations in our awareness may help us understand the neural basis of consciousness. If we could understand how these drugs alter the brain and could see when people flicker into consciousness, we could perhaps understand what circuits are important for consciousness itself. Unfortunately, surgical anesthesia is not an ideal way of testing this because several drugs are often used at once and some can affect memory, meaning that the patient could become conscious during surgery but not remember it afterwards, making it difficult to do reliable retrospective comparisons between brain function and awareness.
An attempt to solve this problem was behind an attention-grabbing new study, led by Valdas Noreika from the University of Turku in Finland, that investigated the extent to which common surgical anesthetics can leave us behaviorally unresponsive but subjectively conscious.