I Forgot to Remember: A Memoir of Amnesia (7 page)

I tell a therapist “I am feeling good today.” However, she notices and writes that my “patience with everyday activities is very short.”

More testing. More results: “Patient manifested mild word-finding difficulties as well as mild to moderate mental calculation difficulties.”
The psychologist, David Wilson, prepares another checklist:

Attention: severely impaired

Language comprehension: severely impaired

Memory: moderately impaired

Calculation: moderately impaired

Abstract reasoning and judgment: severely impaired

A nurse notes, “Patient very angry and agitated at times by external stimuli. Patient and husband require teaching re safety, limitations, medications.”

Hospital notes suggest that Jim and I spent the previous evening home with family. A therapist writes, “Patient stated she became frustrated at home last night, too many people in the room.”

I take (and apparently pass) a “safety evaluation”: crossing a street, walking in a crowd, and riding a bike. On the bike evaluation, I start and stop on command and weave left and right to avoid objects tossed in front of me.

Overnight, my condition seems to have improved dramatically. A chorus of upbeat reports signals my rapid recovery. My discharge is scheduled for the following day. A therapist notes, “Patient has shown remarkable improvement in all areas. . . . Previous cognitive deficits appear resolved.” Another therapist concurs: “Patient
showed a dramatic change in status over the weekend [an odd statement, coming on a Thursday] and upon reassessment, all skills appear to be within normal limits, certainly functional for her to return home.”

Dr. Garcia adds, “Patient is not agitated anymore.”

My social worker notes, “Patient has met almost all her goals in a very short time, but still may have some mild cognitive deficits. [Personality tests] showed a lot of denial, probably related to head injury.” For outpatient follow-up: “No therapies recommended, but psychotherapy is recommended.”

“Home today,” Dr. Garcia notes. “Patient and husband instructed about safety precautions. Dr. Wilson, the psychologist, meets with Jim and me to discuss “the benefits of supportive therapy. They declined, but said they would call if they felt the need. They [probably Jim] indicated that counseling was not a ‘drug’ that worked with them.”

Another battery of tests. I am given the Wechsler Adult Intelligence Scale test and show an IQ of exactly 100 in the final write-up, although buried in the middle of the report is another reference that puts my IQ at 70. On a test of visual-spatial skills, I perform at the level of a six-year-old. And on a personality test, I respond “in a defensive manner, attempting to present herself in the best possible light.”

The psychologist notes my emotional fragility: “She has resources available to handle personal stresses of everyday living, but probably not the aftermath of a closed-head injury. She has strong need for affection and a tendency toward ill-considered, impulsive
behavior. There are definite visual motor deficits which are exacerbated by her impulsivity.” He concludes, “Patient and family’s decision to not accept outpatient services is a negative prognosticator with regard to her overall recovery.”

A nurse restates that my condition has improved “significantly” since the previous weekend. At this time my “cognitive and communication status are functional enough to return home.” She writes, “No further speech or cognitive therapy [is] recommended on an outpatient basis.” The nurse notes that I tell her I will have a nanny to help with the children at home.

Dr. Wilson Garcia writes an upbeat dismissal summary: “On admission to the rehabilitation unit, the patient could not walk and needed assistance with all of her activities of daily living. She was complaining of double vision and photophobic. The patient was started in our head injury program. She made a remarkable improvement to the point that when she left the hospital, she was walking by herself and doing all of her activities without any assistance. On admission to the rehabilitation unit, she was at cognitive level 4, and when she left she was at cognitive level 8.” (Dr. Garcia is referring to the Rancho Levels of Cognitive Functioning Scale, used to assess patients who emerge from a coma. A score of 1 is comatose. A 4 is “confused/agitated.” An 8 is normal.) “This patient made a remarkable improvement,” Dr. Garcia writes, although she was “agitated and she needed medication for that.” Thus improved, he wrote, “the patient went back home with recommendations for outpatient psychotherapy.”

And just like that, I was on my way home.

—Peter Gabriel

A
ccording to Miller family lore, I took a trip to Niagara Falls with my family when I was three. Walking along the rim, I heard the falls roaring in my ears and felt the mist pelting my face. Since I was so young, my parents didn’t yet know just how bad my eyesight was. I could feel the mist and hear the roar, but couldn’t see where those things were coming from. I grew frightened, and that fear swelled into panic. Suddenly I broke away from my mother’s grip and dashed out into the street. Luckily, my parents grabbed me and pulled me out of the road before I could be hurt.

That episode, a visceral combination of sight, sound, and powerful emotion, is part of the shared heritage that binds the members of the Miller family—my family—together. It endures as a rich, nearly palpable memory within the minds of both Miller parents and each of their children, remote in time and space but instantly accessible to any Miller at the mere utterance of a simple prompt:
Remember when Su ran out into the street at Niagara Falls?

Brain scientists call these “episodic memories”—recollections of specific events from one’s lived experience. Episodic memory is thought to be a distinctly human trait, one of the few things that set us apart from the other animals, and perhaps the most important quality that defines each of us as individuals.

But I have no memory of that episode at Niagara Falls. In fact, I have no lingering episodic memory, not a stitch, from the first twenty-two years of my life. My sense of who I am, and my relationship with the other Millers, is entirely based on the events of the last twenty years.

For most people, episodic memory is synonymous with memory itself. But it is only one of at least three different kinds of memory, along with “semantic memory” and “procedural memory.” Each has a different purpose, and each resides in different places within the human brain.

Procedural memory is the remembered ability to perform tasks. We never forget how to ride a bike (or to walk, or to talk, or to swing a bat) because of the fundamental strength of our procedural memories. Semantic memory is the recollection of facts: names, concepts, and even specific events, but not events we recall as scenes from our own life. Most people have semantic memories of Woodstock; those who attended have episodic memories as well. All of my memories from childhood are semantic memories;
stories that have been told to me and stories that I can recite, but that don’t feel like any real experiences I have lived. Anyone who has studied psychology in school will also remember the concept of short-term and long-term memories. Short-term memories are disposable, lasting only seconds or minutes: Post-its from our brain. We use short-term memory to recall the digits of a telephone number to be dialed once, the location of a coconut we just spotted in a tree, and other facts useful for our immediate survival but trivial in the broader course of life. Long-term memory is reserved for information useful beyond the present moment: the directions to our house; the phone numbers of loved ones; our blood type; our first date with a spouse.

Repetition—learning—consolidates short-term memories into long-term ones. The consolidation process can be voluntary, as in studying for an exam, or involuntary, as in those conditioning experiments with animals that used electric shocks and treats to “teach” the rat to find the pellet. Long-term memories can endure for weeks or years or decades. The human brain is forever sifting through memories, preserving the ones that matter for our survival and discarding those that don’t. Memories are Darwinian: Only the ones the brain deems most vital to our survival will, themselves, survive.

That was news to me. Jim remembers a dog-walk conversation that we had less than ten years ago when he first realized how I thought my memory was supposed to work. For most of my life I thought that other adults remembered every fact, every image, every scene they had ever lived, recording memories like a twenty-four-hour security camera. But I guess it makes sense: Who could possibly handle that much memory?

Our brain’s anatomy plays a role in memory; the recall of a
memory is thought to involve several areas of the brain. Different regions record sights and sounds, numbers and names, motor skills and three-dimensional spaces. To recall a whole memory, the medial temporal lobe, a section at the brain’s inner core, must fetch each individual component from different places in the brain. The medial temporal lobe is also thought to help us consolidate short-term episodic and semantic memories into long-term ones, although it does not control formation of procedural memories. The frontal lobe, behind the forehead, seems to help us understand episodic memories by helping the brain place them in context, so that they make sense as a coherent whole. Without a functioning frontal lobe, we might remember the Air and Space Museum as semantic, factual knowledge but forget the childhood visit that is the source of that memory.

Most people who suffer amnesia through injury, such as a football tackle or car accident, forget the things that happened shortly before the traumatic event, a mild form of what is called “retrograde” amnesia. The presumed reason is that the injury disrupts the memory-making process, erasing short-term memories before they can become long-term ones. Thus, a driver who hits a tree might never remember whatever he was doing or thinking in the minutes before the impact, because the collision interrupted the conversion of those items into enduring memories. In more serious cases, such as people with profound dementia or Alzheimer’s disease, the oldest memories tend to be the safest. This is called Ribot’s law, after the nineteenth-century French psychologist who first described this pattern. The destruction of memory “advances progressively from the unstable to the stable,” from new memories to old, Ribot wrote.

Even people with severe cases of retrograde amnesia typically
remember their earliest memories. But not everyone. Daniel Schacter, a Harvard psychologist, studied a man named Gene who, following a motorcycle accident, was “unable to recall a single specific episode from any time in his life.” Gene suffered damage to both his frontal and temporal lobes. He can neither create new memories nor retrieve old ones. His brain does not obey Ribot’s law.