Phantoms in the Brain: Probing the Mysteries of the Human Mind (26 page)

"Mrs. Macken, how are you doing?"

"Fine."

"Can you walk?"

"Sure."

"Can you use your right hand?"

"Yes."

"Can you use your left hand?"

"Yes."

"Are they equally strong?"

"Yes."

After the nystagmus, I asked again, "How are you feeling?"

"My ear's cold."

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"What about your arms? Can you use your arms?"

"No," she replied, "my left arm is paralyzed."

That was the first time she had used that word in the three weeks since her stroke.

"Mrs. Macken, how long have you been paralyzed?"

She said, "Oh, continuously, all these days."

This was an extraordinary remark, for it implies that even though she had been denying her paralysis each time I had seen her over these last few weeks, the memories of her failed attempts had been registering somewhere in her brain, yet access to them had been blocked. The cold water acted as a "truth serum" that brought her repressed memories about her paralysis to the surface.

Half an hour later I went back to her and asked, "Can you use your arms?"

"No, my left arm is paralyzed." Even though the nystagmus had long since ceased, she still admitted she was paralyzed.

Twelve hours later, a student of mine visited her and asked, "Do you remember Dr. Ramachandran?"

"Oh, yes, he was that Indian doctor."

"And what did he do?"

"He took some ice−cold water and he put it into my left ear and it hurt."

"Anything else?"

"Well, he was wearing that tie with a brain scan on it." True, I was wearing a tie with a PET scan on it. Her memory for details was fine.

"What did he ask you?"

"He asked me if I could use both my arms."

"And what did you tell him?"

"I told him I was fine."

So now she was denying her earlier admission of paralysis, as though she were completely rewriting her

"script." Indeed, it was almost as if we had created two separate conscious human beings who were mutually amnesic: the "cold water" Mrs. Macken, who is intellectually honest, who acknowledges her paralysis, and the Mrs. Macken without the cold water, who has the denial syndrome and adamantly denies her paralysis!

Watching the two Mrs. Mackens reminded me of the controversial clinical syndrome known as multiple personalities immortalized in fiction as Dr. Jekyll and Mr. Hyde. I say controversial because most of my more hard−nosed colleagues refuse to believe that the syndrome even exists and would probably argue that it is simply an elaborate form of "playacting." What we have seen in Mrs. Macken, however, implies that such 105

partial insulation of one personality from the other can indeed occur, even though they occupy a single body.

To understand what is going on here, let us return to our general in the war room. I used this analogy to illustrate that there is a sort of coherence−producing mechanism in the left hemisphere—the general— that prohibits anomalies, allows the emergence of a unified belief system and is largely responsible for the integrity and stability of self. But what if a person were confronted by several anomalies that were not consistent with his original belief system but were nonetheless consistent with each other? Like soap bubbles, they might coalesce into a new belief system insulated from the previous story line, creating multiple personalities. Perhaps balkanization is better than civil war. I find the reluctance of cognitive psychologists to accept the reality of this phenomenon somewhat puzzling, given that even normal individuals have such experiences from time to time. I am reminded of a dream I once had in which someone had just been telling me a very funny joke that made me laugh heartily—implying that there must have been at least two mutually amnesic personalities inside me during the dream. To my mind, this is an "existence proof" for the plausibility of multiple personalities.12

The question remains: How did the cold water produce such apparently miraculous effects on Mrs. Macken?

One possibility is that it "arouses" the right hemisphere. There are connections from the vestibular nerve projecting to the vestibular cortex in the right parietal lobe as well as to other parts of the right hemisphere.

Activation of these circuits in the right hemisphere makes the patient pay attention to the left side and notice that her left arm is lying lifeless. She then recognizes, for the first time, that she is paralyzed.

This interpretation is probably at least partially correct, but I would like to consider a more speculative alternative hypothesis: the idea that this phenomenon is somehow related to rapid eye movement (REM) or dream sleep. People spend a third of their lives sleeping, and 25 percent of that time their eyes are moving as they experience vivid, emotional dreams. During these dreams we are often confronted with unpleasant, disturbing facts about ourselves. Thus in both the cold−water state and REM sleep there are noticeable eye movements and unpleasant, forbidden memories come to the surface, and this may not be a coincidence.

Freud believed that in dreams we dredge up material that is ordinarily censored, and one wonders whether the same sort of thing may be happening during "ice water in the ear" stimulation. At the risk of pushing the analogy too far, let's refer to our general, who is now sitting in his bedroom late the next night, sipping a glass of cognac. He now has time to engage in a leisurely inspection of the report given to him by that one scout at 5:55 a.m. and perhaps this mulling over and interpretation correspond to what we call dreaming. If the material makes sense, he may decide to incorporate it into his battle plan for the next day. If it doesn't make sense or if it is too disturbing for him, he will put it into his desk drawer and try to forget about it; that is probably why we cannot remember most of our dreams. I suggest that the vestibular stimulation caused by the cold water partially activates the same circuitry that generates REM

sleep. This allows the patient to uncover unpleasant, disturbing facts about herself—including her paralysis—that are usually repressed when she is awake.

This is obviously a highly speculative conjecture, and I would give it only a 10 percent chance of being correct. (My colleagues would probably give it 1 percent!) But it does lead to a simple, testable prediction.

Patients with denial should
dream that they are paralyzed.
Indeed, if they are awakened during a REM

episode, they may continue to admit their paralysis for several minutes before reverting to denial again. Recall that the effects of calorically induced nystagmus—Mrs. Macken's confession of paralysis—lasted for at least thirty minutes after the nystagmus had ceased.13

Canst thou not minister to a mind diseased, Pluck from the memory a rooted sorrow, Raze out the written
troubles of the brain, And with some sweet oblivious antidote Cleanse the stuffed bosom of that perilous stuff
Which weighs upon the heart?

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—
William Shakespeare

Memory has legitimately been called the Holy Grail of neuroscience. Although many a weighty tome has been written on this topic, in truth we know little about it. Most of the work carried out in recent decades has fallen into two categories. One is the formation of the memory trace itself, sought in the nature of physical changes between synapses and in chemical cascades within nerve cells. The second is based on the study of patients like H.M. (briefly described in Chapter 1), whose hippocampus was removed surgically for epilepsy and who was no longer able to make new memories after the surgery, though he can remember most things that happened before surgery.

Experiments on cells and on patients like H.M. have given us some insights about how new memory traces are formed, but they completely fail to explore equally important narrative or constructive aspects of memory.

How is each new item edited and censored (when necessary) before being pigeonholed according to when and where it occurred? How are these memories progressively assimilated into our "autobiographic self,"

becoming part of who we are? These subtle aspects of memory are notoriously difficult to study in normal people, but I realized that one could explore them in patients like Mrs. Macken who "repress" what happened just a few minutes earlier.

You don't even need ice water to chart this new territory. I found that I could gently prod some patients into eventually admitting that the left arm is "not working" or "weak" or sometimes even "paralyzed" (although they seemed unperturbed by this admission). If I managed to elicit such a statement, left the room and returned ten minutes later, the patient would have no recollection of the "confession," having a sort of selective amnesia for matters concerning his left arm. One woman, who cried for a full ten minutes when she realized that she was paralyzed (a "catastrophic reaction"), couldn't remember this event a few hours later, even though it must have been an emotionally charged and salient experience. This is about as close as one can get to a Freudian repression.

The natural course of the denial syndrome provides us with another means of exploring memory functions.

For reasons not understood, most patients tend to recover completely from the denial syndrome after two or three weeks, though their limbs are almost always still paralyzed or extremely weak. (Wouldn't it be wonderful if alcoholics or anorexics who reject the awful truth about their drinking or their body image were able to recover from denial so quickly? I wonder whether ice water in the left ear canal will do the trick! ) What if I were to go to a patient after he is "over" the denial of his paralysis and ask, "When I saw you last week and asked you about your left arm, what did you tell me?" Would he admit that he had been in denial?

The first patient whom I asked about this was Mumtaz Shah, who had been denying her paralysis for almost a month after her stroke and then recovered completely from the denial (although not from the paralysis). I began with the obvious question: "Mrs. Shah, do you remember me?"

"Yes, you came to see me at Mercy Hospital. You were always showing up with those two student nurses, Becky and Susan." (All this was true; so far she was right on target.)

"Do you remember I asked you about your arms? What did you say?"

"I told you my left arm was paralyzed."

"Do you remember I saw you several times? What did you say each time?"

"Several times, several times—yes, I said the same thing, that I was paralyzed."

(Actually she had told me each time that her arm was fine.)

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"Mumtaz. Think clearly. Do you remember telling me that your left arm was fine, that it wasn't paralyzed?"

"Well, doctor, if I said that, then it implies that I was lying. And I am not a liar."

Mumtaz had apparently repressed the dozens of episodes of denial that she had engaged in during my numerous visits to the hospital.

The same thing happened with another patient, Jean, whom I visited at the San Diego Rehabilitation Center.

We went through the usual questions.

"Can you use your right arm?"

"Oh, yes."

"Can you use your left arm?"

"Yes."

But when I came to the question "Are they equally strong?" Jean said, "No, my left arm is stronger."

Trying to hide my surprise, I pointed to a mahogany table at the end of the hall and asked her whether she could lift that with her right hand.

"I guess I could," she said.

"How high could you lift it?"

She assessed the table, which must have weighed eighty pounds, pursed her lips and said, "Oh, I suppose I could lift it about an inch."

"Can you lift a table with your left hand?"

"Oh, sure," Jean replied. "I could lift it an inch and a half!"

She held up her right hand and showed me with her thumb and index finger how high she could hoist a table with her lifeless left hand. Again, this is a "reaction formation."

But the next day, after she had recovered from her denial, Jean repudiated these same words.

"Jean, do you remember I asked you a question yesterday?"

"Yes," she said, removing her eyeglasses with her right hand. "You asked me if I could lift a table with my right hand and I said I could lift it about an inch."

"What did you say about your left hand?"

"I said I couldn't use my left hand." She gave me a puzzled look.14

The "model" of denial that we considered earlier provides a partial explanation for both the subtle forms of denial that we all engage in, as well as the vehement protests of denial patients. It rests on the notion that the left hemisphere attempts to preserve a coherent worldview at all costs, and, to do that well, it has to sometimes 108

shut out information that is potentially "threatening" to the stability of self.

But what if we could somehow make this "unpleasant" fact more acceptable—more nonthreatening to a patient's belief system? Would he then be willing to accept that his left arm is paralyzed? In other words, can you "cure" his denial by simply tampering with the structure of his beliefs?

I began by conducting an informal neurological workup on the patient, in this instance, a woman named Nancy. I then showed her a syringe full of saline solution and said, "As part of your neurological exam, I would like to inject your left arm with this anesthetic, and as soon as I do it, your left arm will be
temporarily
paralyzed for a few minutes." After making sure that Nancy understood this, I proceeded to "inject" her arm with the salt water. My question was, Would she suddenly admit that she was paralyzed, now that it had been made more acceptable to her, or would she say, "Your injection doesn't work; I can move my left arm just fine?" This is a lovely example of an experiment on a person's belief system, a field of inquiry I have christened
experimental epistemology,
just to annoy philosophers.

Nancy sat quietly for a few moments waiting for the "injection" to "take effect" while her eyes darted around looking at various antique microscopes in my office. I then asked her, "Well, can you move your left arm?"