In the foregoing chapters we have considered the various ways the unity of the self can be disturbed after damage to the brain. One of the important things we learn from these cases is the manner in which mental unity depends on the physical integrity of the brain. In this chapter we will consider a brain structure that figures prominently in the maintenance of mental unity—the corpus callosum.
Splitting the Brain
The upper portions of the brain, including the phylogenetically newest structure, the neocortex, are divided into left and right hemispheres. The corpus callosum, a bundle of nerves containing somewhere between 200 million and a billion fibers, is the main connecting pathway between the two hemispheres.1 This massive fiber bundle connects anatomically symmetric regions of the hemispheres. For instance, cells of a particular region of the parietal lobe of the left hemisphere will connect with cells that mirror the same area in the right hemisphere. It enables each hemisphere of the brain to activate, communicate, and integrate its activity with the opposite side hemisphere (Figure 6-1).
As we saw in the cases of asomatognosia that were discussed in chapter 2., motor control and sensory representation on one side of the body are controlled by the opposite hemisphere. The left hemisphere controls the right side of the body, while the opposite is true of the right hemisphere. Each hemisphere can also control the ipsilateral (same side) parts of the body, but to a very limited degree; the muscles located along the body midline are one such example of parts of the body that are controlled by both hemispheres.
The two hemispheres are also specialized for certain types of activities. As is well known, the left hemisphere controls language capacities in the vast majority of right-handed people. Thus, a right-hander's ability to understand and produce speech, read, and write requires the specialized abilities of left hemisphere. The right hemisphere has a number of its own specialized abilities, including visuospatial functions, attentional
Figure 6–1. The left side of the figure shows a sagittal section of the brain that demonstrates the topography of the corpus callosum, a bridge of axons by which the neurons of the two hemispheres of the brain communicate with one another.
Split-brain patients have this fiber “bridge” cut to control epileptic seizures from spreading from one side of the brain to the other. On the right side of the figure there is a conceptualization of the brain in a person whose corpus callosum is intact (unsplit), as seen from the rear.
control, a special role in emotional behaviors, and a whole host of other capacities to which the right hemisphere makes a greater contribution than the left. When a particular hemisphere controls the function for the entire organism, we refer to that hemisphere as beingdominant for that capacity, although the nondominant hemisphere generally contributes as well to the overall function in question and cooperates with the other hemisphere to produce integrated behaviors.
Humans who have had their hemispheres divided by damage to the corpus callosum either surgically or as a result of stroke, tumor, or other causes demonstrate a partial lack of cross-communication between the hemispheres. These patients are referred to as “split-brain” subjects. The best known and best studied split-brain patients are people with epilepsy who have had an operation called a corpus callosotomy, in which the corpus callosum is cut to prevent the spread of a seizure from one hemisphere to the other.2 Patients who have damage to the corpus callosum offer a unique opportunity to examine to what degree a physical separation of the brain causes a mental division as well.
Due to the manner in which the visual pathways are crossed, visual information from the left visual field goes directly to the right hemisphere, and visual information from the right visual field crosses over to the left hemisphere (Figure 6-2).
Figure 6–2. The visual system.
Objects presented in the left visual field are perceived by the right hemisphere, and vice versa. Normally, information received by the left hemisphere crosses into the right hemisphere via the corpus callosum, allowing “cross-talk” between the two halves of the brain. When this fiber tract is severed, however, as in split-brain patients, visual information from one hemisphere cannot pass to the other hemisphere.
Under normal circumstances, information received by each hemisphere is shared with the opposite hemisphere via the corpus callosum and visual unity is preserved. However, if a split-brain patient fixates his gaze directly forward, and an object is briefly exposed to his right visual field, only the left hemisphere will see it (Figure 6-3). If a picture of a key is briefly flashed in the right visual field, only the speaking left hemisphere will have full knowledge of the word and will be able to say the word aloud. The right hand under the control of the left hemisphere will be able to write the word “key” and be able to pick out a key from a group of objects, but the left hand, under the predominant control of the right hemisphere, will appear completely ignorant of the stimulus.
If a toothbrush is flashed in the left visual hemifield to the right hemisphere, the now limited verbal capacities of the right hemisphere prevent the patient from reading the word aloud. The visual stimulus is received in the right hemisphere; but due to the division of the corpus callosum, the knowledge of the word cannot pass over to the speaking left hemisphere for verbalization. However, when the patient is asked to find the object corresponding to the shown word, the left hand can pick out the toothbrush from a group of tools, while the right hand cannot do this. The same principle applies when objects are placed in the patient's left hand out of sight. Objects felt in this way cannot be named aloud, but the patient may be able to draw the object with the left hand. If two visual
Figure 6–3. If two objects, such as a toothbrush and a key, are simultaneously flashed in opposite visual fields, the split-brain patient can choose the object with the hand controlled by that hemisphere, but that hemisphere has no knowledge of the object that was flashed in the opposite hemisphere. (See text for full explanation.)
stimuli are simultaneously flashed, one to each hemisphere, we find that each hand can retrieve the object shown to its corresponding hemisphere; but the patient, if prohibited from naming the object seen by the right hemisphere, cannot say if the two shown stimuli were the same thing or different (Figure 6-3).3
The Alien Hand Syndrome
The question thus presents itself: To what extent do these patients possess two minds? The idea that two minds can exist in one head actually has a long history. Back in 1844, British physician Arthur Ladbroke Wigan contended that even when the brain was intact, the two hemispheres possessed separate consciousness-each hemisphere having a whole unto itself.4 According to Dr. Wigan, humans possessed a “duality of mind,” even when the hemispheres were in the intact, undivided condition. His belief was largely based on the observation that people who had one of their hemispheres surgically removed could still possess a normal
consciousness. Wigan proposed that the two hemispheres functioned in a coordinated fashion because they had learned to do so. To Wigan, the corpus callosum was “little more than a bond of mechanical union.” The experimental results in split-brain patients have led some scientists to suggest that perhaps Wigan was right, that we should view our two hemispheres as possessing independent minds.5
There are times when callosotomy patients do indeed seem to possess two purposeful minds. The German neurologist Kurt Goldstein described such a patient. In 1908, he reported a fifty-seven-year-old woman who claimed that her left hand acted as if it had a will of its own. The patient, not knowing what had caused this unusual symptom, concluded that her hand must be possessed.
On one occasion the hand grabbed her own neck and tried to throttle her, and could only be pulled off by force. Similarly, it tore off the bed covers against the patient's will. . .she soon is complaining about her hand; that it is a law unto itself, an organ without will [willenloses Werkzeug]; when once it has got hold of something, it refuses to let go: “I myself can do nothing with it; if I'm having a drink and it gets hold of the glass, it won't let go and spills [the drink] out. Then I hit it and say: ‘Behave yourself, hand’ [literally, mein Händchen]” (Smiling,) “I suppose there must be an evil spirit in it.”6
At death, an autopsy of her brain revealed that she had had multiple strokes involving various regions of her brain. But in addition to her multiple strokes, Goldstein discovered an important lesion in the corpus callosum.
I have encountered several cases of this condition now known as the Alien Hand Syndrome (AHS).7 A person with AHS has a hand that acts on its own accord, beyond the patient's conscious, voluntary control. The hand answers the phone and refuses to surrender the receiver to the other hand; it dumps a glass of water into a bowl of cereal; it tries to strangle the patient during sleep, and so on. The sine qua non of AHS is a hand that behaves in a fashion that the patient feels is beyond their control. The hand performs actions that are seemingly purposeful and voluntary, yet the patient claims that the movements are unwanted and involuntary and are not consistent with their conscious intentions.
Patients with this syndrome will differ in the hand that is alien, depending on the location of the brain lesion. When the brain lesion is confined to just the corpus callosum and involves only this structure, it is almost always the left hand that behaves in an alien manner. For instance, AHS
patients who have had their corpus callosum surgically cut develop an alien left hand. Patients with damage to the frontal lobes of the brain often with callosal damage may have a left or right alien hand.8 One of my patients, Stevie, is a good example.
Stevie was a patient in his late sixties who had a left frontocallosal brain lesion (Figure 6-4). One day, one of the resident doctors called me to evaluate some of Stevie's unusual behaviors. After his stroke, Stevie had mild weakness of his right arm and hand, which fortunately resolved almost immediately after the stroke. However, within days, the hand that had been so affected started to display some other rather troublesome behaviors. The first thing Stevie noticed was that at times he could not voluntarily make the hand perform the actions he intended. For instance, if Stevie was holding a cup of juice in the right hand, he might be unable to place it back on the hospital tray, or he might involuntaily crush the cup in his hand, spilling its contents all over him in the process. On one occasion he suddenly threw a spoon across the room. All these actions were understandably of great concern to Stevie. He found these odd behaviors not only inexplicable, but also frightening.
When I first met Stevie, he was sitting in a chair near his hospital bed. He appeared composed and alert. I introduced myself and shook his hand, but he was unable to release his grasp for several seconds, although I requested several times that he do so. As I sat down on Stevie's bed and prepared to ask him about his difficulties, I suddenly noticed his right hand creeping up his leg. At first, Stevie appeared unaware that his hand was on the move,
Figure 6–4. Stevie suffered a deep, left, medial frontal infarct (loss of blood to that region of brain—what is commonly known as a “stroke”). The MRI of his brain demonstrated that the stroke resulted in damage to the corpus callosum, which led to the disinhibition of his mischievous alien right hand.
but as the alien hand inched up his leg, he noticed it. He appeared alarmed, and with his other, normal hand, he pulled the alien hand off his leg. At this point, the right hand actually seemed to resist the action of the normal hand. The right hand seemed to try to escape, but Stevie held it so tightly it couldn't get away.
When he decided the hand was quiet, he released it. Almost immediately, the right hand returned to his right knee and began to climb the leg. This time Stevie was ready, and he grabbed it before it could get very far. He held onto the hand even longer, for a good minute or two, before he released it. Nonetheless, when he let the hand go, within seconds it was pulling at his hospital gown. Now Stevie kept an eye on it, but once again it crept up his leg and he was forced to yank it off and restrain it.
FEINBERG: What happened?
STEVIE: What happened. . . it got close to my genitals. . .
FEINBERG: Excuse me?
STEVIE: I got close. . .
FEINBERG: You got close to your genitals?
FEINBERG: Who did? What did?
STEVIE: This thing here [indicating the right hand, which he was holding tightly by the left].
FEINBERG: What is that?
STEVIE: My right arm. My right arm.
FEINBERG: What's the problem with it?
STEVIE: It gets out of hand!
FEINBERG: It gets out of hand, so to speak, huh?
FEINBERG: In what way is that, sir?
STEVIE: It just flies off uncontrolled.
A few moments later I attempted to hand Stevie a spoon. He happened at this moment to be holding the left hand in his right, and with his left hand, he tried to grasp the spoon. Another fight between the hands ensued, but this time it was the left hand that struggled to get free.
FEINBERG: What just happened there?
STEVIE: I was trying to take the spoon with my left hand, and there was a disagreement between my right and my left.
FEINBERG: What disagreed with what?
STEVIE: I think what happened was, I knew I wanted to take the spoon, but
the right hand wanted to be in charge.
FEINBERG: And your left hand didn't agree?
STEVIE: No sir. It never agrees. . .
FEINBERG: It never agrees?
STEVIE: That's right.
After he was discharged from the hospital, I saw Stevie as an outpatient. Now dressed in street clothes, he appeared to be back to his former self. However, the alien hand continued to be a major problem, and Stevie complained about it bitterly. He now referred to the right hand as the “bad one” or the “naughty one,” and the left hand he called “the boss.” The two hands continued their fights, and the left hand, under Stevie's voluntary control, began to “beat up” the right hand. He showed me the scars on the right hand as proof of these battles.
STEVIE: This is the bad boy [indicating the right hand], and this is the good boy [pointing to the left]. I control the good boy. I can't control the bad boy. That's been the problem. This hand over here—which is the good boy-is very dominant over the bad boy—this one here. Because he is my boy [pointing to himself]. You understand that? He does my wishes. . .and “bad boy” goes off on his own.
Stevie also had a lot of difficulty with coordinating actions of the two hands. For instance, tying his shoes was difficult, and zippering up a jacket with both hands was nearly impossible. These difficulties, however, were small in comparison to the problems he experienced with the aggressive actions of the alien hand. The right hand had a mischievous, almost hostile, attitude toward Stevie. The hand was prone to tear up letters. The hand even tore up money—needless to say, a particularly troublesome symptom. He felt the hand at times seemed to try to do him harm, and he continued to retaliate against the right hand with the left.
On one visit he wore a bright blue sock, which he felt kept the hand subdued. Despite my efforts to treat the hand with a series of medications, it remained quite out of control.
STEVIE: The fact is, I ruined about three or four pairs of pajama pants.
FEINBERG: Really? How?
STEVIE: Because I have found that I have been beating up on it and I'm beginning to feel it.
The aggressive quality of Stevie's alien hand is not an uncommon feature of the syndrome. As was in the case in Goldstein's patient, strangling actions are a particularly frightening problem and have occurred in
several cases. The case described by cognitive neuroscientist Michael Gazzaniga had a very violent left hand:
The patient would sometimes find himself pulling his pants down with one hand and pulling them up with the other. Once, he grabbed his wife with his left hand and shook her violently, while with the right trying to come to his wife's aid in bringing the left belligerent hand under control. Once, while I was playing horse-shoes with the patient in his backyard, he happened to pick up an axe leaning against the house with his left hand. Because it was entirely likely that the more aggressive right hemisphere might be in control, I discretely left the scene—not wanting to be the victim for the test case of which half-brain does society punish or execute.9
Another patient with an aggressive alien hand was reported by neurologist D. H. Geschwind and coworkers.10 This patient was a sixty-eight-year-old woman who had a stroke that was confined to the corpus callosum. Soon after the stroke, the family had noted that the patient's left hand was “performing on its own.”
She awoke several times with her left hand choking her, and while she was awake her left hand would unbutton her gown, crush cups on her tray, and fight with the right hand while she was answering the phone. To keep her left hand from doing mischief, she would subdue it with the right hand. She described this unpleasant sensation as if someone “from the moon” were controlling her hand.11
These alien hands seem to want to do the opposite of the person's conscious intentions, a condition called intermanual conflict. Goldberg and Bloom described a fifty-three-year-old woman who had a stroke that damaged parts of her right frontal lobe and the corpus callosum.12Her left hand wandered about in what they described as the “alien mode” when it was not restrained.
She reported an episode during a meal when the right hand was putting a spoonful of cereal in her mouth while, at the same time, the left hand brought a piece of bread to her mouth. Another incident occurred when the right hand picked up a bowl of hot soup and the left hand threw it to the ground. On another occasion, her left hand began to remove a cigarette from her mouth as she was about to light it with the right hand. She stated that the left hand “was trying to keep me from smoking.”13
Several patients have described situations when the normal hand opens a drawer or closet and the alien limb will close it. Neurosurgeon Joseph Bogen reported that one of his callosotomy patients, RY, while buttoning up his shirt with one hand, found that the other hand was “coming along right behind it undoing the buttons.”14 Stevie's attempts to restrain the alien hand are also a characteristic feature of the disorder. It has been dubbed the “Dr. Strangelove effect.”15 This appellation derives from the character in the movie by the same name, vividly portrayed by Peter Sellers, who feels compelled to make a Nazi salute while the other limb attempts to restrain it.
The Self Finds a Way to Remain Whole
These examples do suggest that when we divide the brain physically, we also bisect the patient's mind. But to what degree is consciousness actually divided in the split-brain patient? Despite our ability to objectively demonstrate the lack of brain integration under certain circumstances, and the occasional occurrence of an alien hand syndrome, the vast majority of people with split brains do not feel different than they did prior to the division of their corpus callosums. Indeed, one of the most striking features about split-brain patients is the degree to which they act, feel, and experience themselves as completely intact.16 I am astounded that split-brain patients never wake up after their brain surgery, shake their heads, and proclaim how peculiar they feel! These people under most circumstances have no subjective “inner sense” that their brain has been divided. How can this be?
There are a number of possibilities. First, not all the information coming into the two hemispheres is completely crossed, so each hemisphere may, independently from the other, receive a whole composite of the world. The amount of missing information is minimized, and the patient is less likely to notice anything perceptually different or wrong, even if the two hemispheres have limited “cross-talk.” Incoming signals for sensations such as temperature, position of the joints in space, touch, and pain from each half of the body project for the most part to the opposite hemisphere. But sensory information passes through the spinal cord and its rostral extention, the brainstem, on its way to the cortex, and there are numerous uncrossed pathways at these lower levels. So each hemisphere receives ipsilateral (uncrossed) projections, as well as crossed contralateral projections, whether or not the callosum is intact.
The same is true for motor behavior. Each hemisphere, though predominantly
controlling the opposite side of the body, also has to a certain extent control over the ipsilateral limb. Additionally, each hemisphere can control eye movements in both directions. It has also been shown that the visual fields are not entirely divided by callosotomy, and primitive visual information from right and left hemifields are partially shared; for some types of elementary visual processes, such as simple detection of light or form, cutting of the corpus callosum does not fully separate the visual fields.17
With the brainstem and spinal cord left intact, one does not really split the ego, or split the neurological self, by cutting the corpus callosum. Rather, one splits certain patterns of information processes and certain patterns of voluntary control that may on occasion lead to disunity of experience and action. One cannot help wondering what would happen if one actually divided the entire nervous system in half, actually split it right down the middle—through the corpus callosum, through the brainstem, all the way down through the spinal cord. While the thought of this experiment is somewhat gruesome, it is fascinating nonetheless to think about whether one would have a feeling of distinct division—a feeling of missing one's other half.
Moreover, even though the corpus callosum is sectioned, there are alternative pathways between the two hemispheres of the brain that remain intact. Some of the information that is exclusively crossed and destined for one hemisphere only may pass to the other hemisphere in the absence of a corpus callosum. One such pathway, though quite small in comparison to the corpus callosum, is called the anterior commissure. It may remain intact in some patients with callosal lesions that are either surgically or accidentally induced. An intact anterior commissure makes some degree of hemispheric “cross-communication” possible, even if the corpus callosum is divided.18
As we have already seen, patients who have split-brain operations do not share complex visual information such as written words across the visual fields. If a picture of a full face is flashed in the center of the visual field, only the right half of the face is seen by the left hemisphere, and only the left half of the face is seen by the right hemisphere. Under these conditions, the right hemisphere should be unaware of what the left hemisphere saw, and the left hemisphere is unaware of what the right hemisphere saw. That is, when the two halves of the stimulus don't match—if the left side is a female face and the right half is a male face, for example—the patient is unaware of the disparity. These unmatched stimuli, which neuropsychologists have used to study the divided hemispheres, are called chimerics.19
From the standpoint of subjective unawareness, it is a rather remarkable fact that these patients are not aware that they have seen chimeric figures. They do not comment that they have seen the halves of things, even though the hemispheres are processing simultaneously competing stimuli.
Trevarthen, a psychologist and an early investigator in this area, discovered that even though one of his patients was able to respond toboth sides of a chimeric simultaneously, he never became aware that a stimulus was a chimeric.20 Psychologist Jerre Levy noted that when the two hemispheres were given conflicting chimeric information,
if the right hemisphere responded, there was no indication, by words or facial expression, that the left hemisphere had any argument with the choice made, and, similarly, if the left hemisphere responded, no behavior on the part of the patient suggested a disagreement by the right hemisphere.21
Levy noted that when the patient's left hemisphere responded verbally, and even confabulated a response to a stimulus that only the right hemisphere knew, the right hemisphere of this patient never indicated that it knew via a “frown or head shake”whether the response was in error. And the patient's left hemisphere did not verbally object to a right hemisphere response.22
Trevarthen further noted that when a verbal response was called for, split-brain patients shown only the right side of a face completed the missing left side and reported seeing a whole face.23 Thus, each hemisphere is capable of experiencing a “whole”stimulus, though each actually saw only half. When patients fictitiously make up or fill in whatever is missing of the stimulus in the ipsilateral hemifield, we call this “confabulatory completion.”24 In this manner, each hemisphere may be capable of generating a complete and total subjective experience of the world. If this is the case, it may be that the split-brain patient has two conscious and partially independent half brains, each one aware of what it would normally be aware of in the intact brain state and making up or filling in what it is missing in the divided state (Figure 6-5).
As we have seen, some philosophers have argued that indeed this is the case, that there are two “consciousnesses” in the split-brain patient. However, if this were true, the two hands (hemispheres) would never agree on anything! So I doubt that the two hemispheres have two independent yet concurrent “consciousnesses” or volitions. Rather, I suspect that given whatever the patient's momentary intentions are, either hemisphere has the capacity to organize and control behavior. Depending on the circumstances,
Figure 6–5. Each hemisphere of the patient with a split brain may “fill in” the missing half of a stimulus. In this case, a “chimeric” stimulus—left half a woman's face, right half a man's face—is presented to opposite visual fields. Each hemisphere of this patient's brain imagined that it saw a whole face. This is an example of confabulatory completion.
the other hemisphere will adopt a subordinate role and function in a fashion along with whichever hemisphere happens to be in control. Only momentarily does dual consciousness exist.
The separation of cognitive functions that is created when the hemispheres are divided by corpus callosotomy is one of the most striking findings in behavioral neurology. However, I am just as impressed with the split-brain patient's ability to experience a unified awareness in spite of the seemingly overwhelming obstacle of the surgical division of the hemispheres. The fact that one hemisphere may oppose the other in the split brain only highlights the extraordinary fact that under most circumstances these patients behave in a fully integrated fashion and subjectively feel unified. Moreover, despite their troublesome hands, my patients with alien hands do not experience any change in their basic personalities. In the same ways that they did before they developed neurological problems, these patients still love their wives and walk their dogs. Rather than arguing about whether the split-brain patient possesses two consciousnesses, I would contend that it is an extraordinary fact that split-brain patients largely retain their ability to function in a unified fashion despite callosal division.
I have encountered patients with other neurological conditions who demonstrate a remarkable resiliency of the self despite their neurological
damage. Although the majority of patients I examine have dramatic behavioral problems that are caused by significant neurological disease, occasionally I see a patient who has relatively mild difficulties but a major neurological disorder. One case that was remarkable in this regard was Sonia.
Sonia was a thirty-two-year-old secretary who came to me accompanied by her brother. Sonia had an unremarkable background. There was nothing unusual about her childhood and she was a good student in high school and college. She graduated from college and became an executive secretary at a large computer firm. Everything was fine with Sonia until a few months ago when her brother noticed that she had become mildly paranoid. Otherwise, Sonia had been able to function at home and on the job from day to day without any major disruptive incidents. She saw another doctor who wanted to give her antipsychotic drugs, but he first asked me to perform a neurological exam to determine whether anything else might be wrong with her.
While her neurological exam was normal, I did notice when she walked into my office that her head was unusually large. Why this characteristic did not catch anyone else's attention, I have no idea. I pulled my tape measure out of my lab coat to determine the circumference of her head. Sure enough, it was two standard deviations larger than normal, so I ordered a CAT scan (Figure 6-6). The scans shocked me. They revealed that over three-quarters of her cerebral cortex was missing: Just a ribbon of cortex around the outside of her brain remained, and her fluid-filled lateral ventricles, which are normally no
Figure 6–6. As you can see from the figure of Stevie's brain (Figure 6-4), the lateral ventricles—the curved fluid-filled spaces inside each hemisphere of the brain—are no larger than two index fingers.
In Sonia's case, however, the ventricles have abnormally ballooned out within her hemispheres to occupy a space the size of two very large baked potatoes inside her skull.
larger than the size of two index fingers, were the size of Lake Erie. Most of her brain was composed of cerebrospinal fluid, a condition called hydrocepbalus. It was amazing to me that Sonia had made it so far in life with so little brain. Somehow, she managed to make the most of what she did have.
Hydrocephalus as severe as Sonia's, when it develops suddenly in an adult, is fatal. If the lateral ventricles balloon out to this degree, they rapidly compress the surrounding brain, and if the condition is not immediately corrected neurosurgically, the patient goes into coma. The reason Sonia survived with this striking degree of ventricular enlargement that left her with so little brain is that her hydrocephalus was present from birth or early childhood. In her case, the ventricular enlargement developed gradually, and her nervous system was able to accommodate to the increased pressure. Also, her problem developed when Sonia was very young and, in general, the child's brain is more resilient than that of the adult.
Another patient who showed a remarkable capacity to adjust to brain damage was Seymour. The complaints that initially brought Seymour to my office were mild, so I wasn't expecting to find much wrong with him neurologically. As with Sonia, however, something had happened to Seymour's brain in the past, something that only came to light many years later.
Seymour came to my office with the complaint that he was “a little nervous.” He was an older man, well into his seventies. He was immaculate in appearance, spoke in a refined manner, and carried himself like a real gentleman. He was now retired, but had been an accountant his entire adult life. His only complaint was that he occasionally gets a little “nervous” and he would like to try some medication that might calm him down. The only unusual thing occurred when we went over his past medical history. Initially, Seymour denied any surgical procedures, but he subsequently recalled that, indeed, he did have a “bit of surgery” on his brain when he was much younger, perhaps when he was in his late teens or early twenties. He was not sure why the surgery was performed, but he thought it may have been for “nerves.” In any event, that was a long time ago.
Now I was really curious. Before I treated Seymour with any medications, I suggested we get a CAT scan and see exactly what was done to his brain. When I saw the scan, once again I was amazed (Figure 6-7). Some time in his past, Seymour had had a frontal lobotomy, and substantial portions
Figure 6–7. Despite his normal appearance and neurobehavioral exam, Seymour's CAT scan revealed that he had undergone a frontal lobotomy. The surgical procedure created symmetric areas of encepalomalacia in both of Seymour's frontal lobes. The areas of damage extended from the front of the lateral ventricles to the region where the frontal lobes should have been.
of his frontal lobes had been removed. I assume Seymour had the operation for a psychiatric condition, but to this day neither Seymour nor I know why the operation was performed.
Patients like Seymour do not come along every day. Indeed, I have never since seen a patient who was unaware that they had had a lobotomy.