From the outside, it just appears that a concussive is quirky and unreasonable about the noise of garbage trucks and the need for quiet in the household. He is slow in responding to simple questions about car keys, and asking such questions can make him unaccountably distressed. This does not make much sense to others, who are not aware of the processing overload that is going on under the hood.
You will often hear concussives complain that they “can only do one thing at a time.” And this is true. The sad fact, however, is that normal cognition, even when only doing one thing at a time on the surface, often requires many layers of simultaneous processing in the brain.
DAEMON GUILT. Around this time, still in the early days after the accident, I had my first encounters with episodes of undifferentiated guilt: a guilt that crept up on me, and was triggered by subconscious processes, but which was not bound to any specific intentional actions I had taken. Such guilt feelings became quite common over the years.
Typically, I would be unsuccessfully trying to perform some task in my life—such as feeding myself during the apple-or-salami incident. I knew that I knew exactly how to perform the task, but I could not seem to access that knowledge of how to do it. At this point a “guilt daemon” would fire up, presumably to get me to stop screwing around and conform to societal conventions of handling my own problems, instead of acting so helplessly: after all, as far as the daemon was concerned, all the knowledge to get the job done was available to me.
I was left with this often-repeating circumstance where I knew how to act, knew what was to be done, felt guilty that I was not acting, but was powerless to initiate action toward my goals. But I was unable to make the guilt daemon “understand” that there was no way I could live up to the principle for which I was being held accountable. So, it would not go away, and actually made things worse by itself consuming precious resources.
Several years after the crash, Jake and I were leaving the Century Movie Theater in Evanston. Jake recognized that I was having some trouble walking—the parallel lines and moving planes on the long escalator ride down to the lobby were playing havoc with my highly vision-dependent balance systems. So, just as we were exiting through the glass doors of the theater, he said, “You can stay here if you want, and I’ll go get the car.”
Because of cognitive slowing (which we’ll discuss in detail in a later section), one symptom of which was my inability to turn spoken sentences into meaning quickly enough to keep up with normal speech, I did not quite make out what he said. After some error correction, based on the few words I did get, and the overall sound of his utterance, I mistakenly thought Jake had said, “You can stay here if you want, and I’ll try to make out what those are.”
There were some pretty female Northwestern University grad students on the sidewalk to our left. As near as I could tell, Jake, an always-interested bachelor, was referring to the attractive women, although I couldn’t figure out what his comment meant. I wondered what my staying by the door of the theater had to do with Jake and the students.
While I was thinking this over, I crossed the street with Jake, slowly walking alongside him, following him back toward the car. I looked toward the women and said, “I’m sorry, Jake, could you explain what you mean? I don’t know how to decide if I should wait while you figure out what something is.”
At exactly the time I started to speak, I also began to feel very distinctly guilty, which was unpleasant—a feeling of unnamed dread.
But this time, rather than deal with it on my own, I mentioned it to Jake. I was ready to look for some answers, and to analyze the details of what had just happened. Jake was game: scientific analysis of most any aspect of the natural world was something that he and I engaged in often. So we sat in his car and worked it out.
When Jake first spoke his sentence, I honestly did not hear all of the words clearly. This happens to all of us. Fortunately, however, most of us are almost instantaneously—and certainly without conscious thought—able to disambiguate an incorrectly heard utterance by replacing some words with others, so that the expressions make sense in the current circumstances: “. . . stay here if you want, and I will go get the car.” In computer science terms this is simply a matter of meeting the constraints of the words that we did hear and those of the context in which we heard them, while searching for possible candidate-phrases with which to fill in the blanks, and then ranking our proposed solutions for viability. At some point one of the solutions is deemed good enough and we abandon further search.
However, my own ability to perform this kind of constraint-based searching for the purposes of verbal stream error correction had been compromised, which is why certain kinds of conversations could make me very tired, very quickly. Yet this was a matter of degree: my error-correction processing was mostly still intact—just moving slowly.
Thus by the time I had determined the need for further information, formed the sentence that could request this information from Jake, and constructed the sounds necessary for uttering the question, a different part of my brain had already figured out what Jake had actually said.
Under the hood, so to speak, two daemons, S (Search for meaning) and Q (ask Question), had been started up, followed later by a third, G (Guilt). S was an independent search daemon whose job it was to find out the meaning of Jake’s utterance. Failing to retrieve enough information to disambiguate the sentence on its own, S activated a query daemon, Q, to ask Jake to explain. But in the meantime, S kept searching. Because Q involved the forming of an utterance—a spoken sentence—it became the center of my attentional focus. That is, I was intentionally asking Jake a question; thus, everything else receded into the background, including the ongoing search by S for the error-corrected meaning of what Jake had originally said to me. In the middle of actually asking Jake the question, S had simultaneously figured out what Jake had said—obviating the need to ask the question at all.
Ordinarily this information from S would rise to the conscious level, and would abort the question-asking process, Q. But because of the brain damage, this communication from S to Q (and thus to my conscious level) could not take place. I still didn’t “know” what Jake had said in any way I could make use of. For example, I couldn’t make use of the information to stop walking, and tell Jake, “Thanks for your consideration. I’ll wait for you here.”
Meanwhile, under the surface, the preconditions for firing off a guilt daemon had been met: I was inconveniencing my friend, who was trying to help me. I was “pretending” not to have heard what he said. I was exacerbating my deceitfulness by now asking him to clarify his statement, even though I already knew the answer to my question. Each of these was a violation of one of my moral principles, and so an internal censure had been issued: guilt (G) rose of its own accord, independent of any conscious logic. I could not control it, and I could not make it go away.
It is interesting that whatever nonconscious process it was that triggered the guilt daemon (G) had access to both the process of my asking for information (Q), and the process that was reporting already having found that same information (S). But G did not have access to the abnormal structural constraint caused by the brain damage: while I had retrieved the missing information, I could not access it in any way that was useful to me. This makes sense, we might suppose. The first two processes are normal, and the guilt daemon is set up to handle them; but the guilt daemon was not designed to make use of a constraint solely caused by brain damage.
My intuition is that this had to do with what we will later understand were my ongoing difficulties with the integration of central attentional focus, and peripheral contextual information—important parts of the visual/spatial reasoning capabilities of the brain. In this case the detail/focus aspect of my interaction with Jake was my asking him questions about what he meant, and the peripheral context was that I had simultaneously already figured out what he had originally said.
Alas,
guilt is not pleasant, especially when there is a feeling of having done something really bad but not knowing what it was. So this was a big moment for me—to understand why I had been feeling so guilty, so often, for two years, yet could never figure out how to “act right” so that I would not suffer from such relentless internal censuring. Our analysis allowed me to form a plan about this kind of recurring guilt such that, while it did not allow me to stop the emotion from occurring, it did allow me the solace of understanding what was happening to me: I could now ignore my guilt and simply shrug my shoulders in wonder at the marvelous design of the human mind.
BALANCE IN THE SYMBOLIC WORLD
Unless you have, yourself, lost efficacy in your balance system, you probably have no idea how devastating the effects of this can be in one’s life. Because of inner-ear damage—yet another result of the crash—I had to deal with balance issues every day. In this section we’ll start with the obvious challenges with basic motion for the concussive, but then must get progressively more sophisticated in our analysis as we examine the effects of balance difficulties on hearing, body sense, and even the most elemental aspect of cognition that make us human: the symbol creation of thinking.
THE THREE BALANCE SYSTEMS. Roughly speaking, the balance system uses three overlapping components: (a) the vestibular system, or “inner ear”; (b) the visual system; and (c) proprioception, the feeling of our bodies in the space around us—a position-movement sensation. While the vestibular system is primary, the other two are also very important, and the interaction among the three systems is far more complex than we generally consider.
Our vestibular and proprioceptive systems give direct information to our bodies to help them stay upright. But there is also a critical feedback loop between these two systems—processed in our brain stem—and our eyes. The vestibulo-ocular reflex, for example, takes input from the sensing of movement through neurological assessments of position and velocity and uses this information to stabilize our gaze by making microcontrolled adjustments in the extraocular muscles in the eyes so they counter head and body movements: the instant we move our head, our eyes adjust to stay fixed on an object. You can see this effect by looking directly at your own eyes in a mirror and moving your body around. In addition, these subsecond microadjustments are integrated with our ability to simultaneously adjust for the pursuit of objects moving in our environment as well, so we can turn our heads and bodies while still following the path of a bird flying across our yard. So our balance system controls our eyes.
But the relationship between our eyes and our balance system works in the other direction as well, and our eyes control our balance: when our vestibular system is underfunctioning—as often happens with head injury—our eyes can take over much of the load. We can illustrate this with a simple exercise: (1) Stand on one leg with your eyes open and your other knee up high—usually this is not too much of a problem. Notice the muscle adjustments in the foot that is on the floor. (2) Close your eyes, but continue standing on the one leg. Depending on how effective your vestibular and proprioceptive systems are, you will experience varying degrees of increased difficulty when losing your visual input (and a corresponding increase in the microadjustments in your foot). The more your balance is dependent on your vision system, the more you’ll start to wobble when you close your eyes.
MOTION DISORIENTATION. Like many concussives, I had many episodes involving motion sickness that gave me trouble. For example, several weeks after the crash I tried to take the El train downtown. Within a few stops I was so sick that I vomited in the train car and had to roll myself out through the doors onto a platform.
“I’m sorry!” I said to the variously disgusted and concerned passengers. “I don’t know what happened. I’m sorry.” It took me three hours to recover sufficiently before I could walk home.
On an evening almost a year later, I was exhausted from teaching class and it was hard for me to walk—it had taken me an hour to get down the stairs of the classroom building. I didn’t want to face walking up the stairs again in the building where my office was, so I talked myself into thinking it would be okay to take the elevator up to the sixth floor. This was a mistake. Once the elevator doors opened on six, I tumbled out onto the floor and crawled to the wall, where I could prop myself up. I rested there for fifteen minutes, pretending to be sitting on the floor reading a book whenever students came by. Then I crawled to my office on my hands and knees, and rested on the floor for an hour to recover my equilibrium.
We’ll see later that because of the strong link between our balance systems and our eyes, it is possible that many people who suffer from what they assume to be congenital motion sickness would improve by treating their visual systems.
BALANCE, VISION, AND THOUGHT.* Because I had suffered vestibular system damage, this meant that my already-overtaxed and poorly functioning visual system had to take on the additional load of providing for many of my balance needs as well. But at the same time, any sort of high-level thinking also required the use of exactly those same visual/spatial systems in creating the internal images of thought.
Thus we have the following: Under the cognitive load of thinking—which almost always entailed visualization, pattern matching, and generating the spatial imagery to form analogies—my damaged brain would rapidly grow fatigued. The visual/spatial circuitry would get overloaded, and could no longer manage its double-duty making up for the vestibular system, and I would lose my balance. As we will see, the same thing would happen when I had to use my visual/spatial circuitry to interpret meaning in complex sensory input—such as speech, or the complicated visual patterns on store shelves. One of the worst combinations would be when I had to use the visual systems in my brain simultaneously for both complex thinking, or sensory interpretation, and intense balance calculations.
As my brain fatigue grew during even short periods of cognitive load my balance would grow progressively worse, and nausea would almost immediately set in. Depending on what I was thinking about, or the physical task I was working on, I would start to lose my balance within five minutes.
I developed a surreptitious remedial balance technique: whenever I walked around the university—where I had to think throughout the day—I would simply run an index finger along a wall as though I were goofing around. People tended not to notice this much, especially if I kept my hand low on the wall, and it was much better than looking drunk by weaving around in hallways and classrooms.
A neurological oddity that presented itself in my case, and that you might notice in a concussive who is having balance problems, was that my index fingers would flex upward, with my thumbs out-thrust, while the rest of my fingers were relaxed downward, forming a flexed “L” between the thumb and index finger of each hand. If you put your arms out at slightly less than a forty-five-degree angle and raise your index fingers in this way, you will likely perceive this as a kind of balance-vigilant position.
WHERE THE BODY ENDS. Our balance systems are integrated with other important but little-considered systems as well. For example, a collection of nerves in the superior parietal lobe is thought to help us distinguish where our bodies end and where the external world takes over. Without the capability to make this distinction, it would be difficult for us to navigate our way through a world filled alternately with obstructions and openings through them. At times, brain activity in this area is naturally reduced and our sense of where our bodies end is appropriately minimized—for example, when we drop off to sleep, or fall into a deep meditative state.
This body-demarcation sense is something that normals take for granted, but it can be quite troubling when it disappears at unnatural times. It is an interesting question to consider the relationships among the brain’s visual cortex, our balance systems, and this body-versus-surroundings demarcation sense. My experience suggests that there is a link. Under brain stress—primarily visual, and especially when making excessive demands on my visual system for
balance—the boundary line between my body and the rest of the world became blurred.
This was most easily noticed in my almost ubiquitous (though relatively mild) difficulty passing through doorways, down tunnels (such as stairways and Jetways), and getting into cars, when my brain was tired. I would have to put my arms out to “feel” the spatialness of the opening—using my eyes to carefully examine the distinctions between my hands and the surrounding objects—and thus guide myself through manually.
A more striking example of this loss of body-environment demarcation occurred five years after the crash, as a result of a set of intense visual-balance demands:
One of the fifty-foot trees in my back yard had been identified as having Dutch elm disease, which can spread throughout a neighborhood, so it had to be cut down. High-ladder tree work of this kind is intense, and not for the faint of heart. I couldn’t afford to have it professionally removed, so in the end I had to manage it on my own.*
I knew I would have to contend not only with the normal rather striking visceral reactions of being so high up, but also with the added complications from my brain damage. The following diary passage is from a day when I had climbed thirty feet into the tree to cut off the highest branches, which themselves reached another twenty feet over my head. This episode simultaneously taxed my visual/spatial system for three separate tasks: the intense spatial planning of where the heavy tree branches were to be cut, and would fall; the meaningful interpretation of the incoming barrage of sensory input; and the essential need to keep my balance based primarily on the constantly moving visual input.
The Ghost in My Brain Page 8
