Supernormal. Мэг Джей

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СКАЧАТЬ Sam came across passages that described people who divorced as adulterers, he read and reread those night after night, trying to make sense of the strange language and of his strange new life. One afternoon in the car, Sam worked up the courage to ask his mother a question. “Did Dad leave because he’s an adulterer?” Sam inquired casually as he hunched down in his seat and forced himself to stare straight ahead. Sam’s mother slowed the car like she was waiting for her son to continue, so he said, “You know, was there some other woman?”

      Sam’s mother put her foot back on the gas and exhaled quickly. “God, no,” she scoffed. “No one would want him.”

      Sam did not read the Bible anymore after that.

      That December, Sam thought Christmas would never come. Christmas was something so special, so magical—and so wonderfully scripted and ritualistic—that it, and now it alone, seemed untouched by his new circumstances. Santa Claus brought the presents and Santa Claus had not changed. On Christmas Eve, some time after going to bed, Sam needed something—water, maybe—so he tiptoed down the hallway toward the kitchen. When he closed in on the den, it took a moment to understand what he was seeing, but soon he recognized that his mother was wrapping and arranging presents that were supposed to be coming from the North Pole. Sam turned around and sneaked back up the hall, and as he crawled into bed, he realized that all of the men in his life were gone: his father, God, and Santa Claus.

      ***

      Sam recalls these moments so vividly because they are what are sometimes called flashbulb memories. Flashbulb memories are recollections that feel illuminated and frozen in time, like snapshots in the mind. Harvard psychologists Roger Brown and James Kulik introduced this term to the scientific community in a 1977 paper in which they suggested that when we find out about events that are shocking or significant, we permanently imprint those surprises in memory, like photographs. Prototypical flashbulb memories are those of iconic, culturally newsworthy moments, such as the way almost everyone can recall where they were and what they were doing on the morning of September 11, 2001. We probably all remember with great clarity and brightness how we found out that planes had crashed into the World Trade Center, as well as what we did just next.

      While Brown and Kulik were interested in how we remember shocking public events, their findings revealed that the cultural and the personal intersect. In their survey of white and black Americans, equal numbers of respondents reported flashbulb memories for hearing about the assassination of President John F. Kennedy, while far more blacks than whites also reported such memories for learning about the assassinations of civil rights leaders Martin Luther King Jr. and Malcolm X. This underscores the fact that flashbulb memories are not simply a catalog of events that are objectively important or out of the ordinary. Most crucial is how relevant or consequential an event feels to the individual. That is, flashbulb memories are emotional memories, and such memories have long been known to carry special significance in our brains and in our lives. In fact, the power and permanence of emotional memories was one of the founding—and remains one of the most enduring—questions in the study of the mind.

      In 1890, the father of American psychology, William James, wrote that some memories seem indelible because “an impression may be so exciting emotionally as almost to leave a scar upon the cerebral tissues.” Though in the nineteenth century no one understood quite how this scarring might work, many of James’s contemporaries were reaching similar conclusions. The French neurologist and founder of modern neurology Jean-Martin Charcot puzzled over how memories of shocking events were not only persistent but could also be all-consuming, functioning as “parasites of the mind.” In Austria, the neurologist and father of psychoanalysis Sigmund Freud similarly posed that his patients “suffer mainly from reminiscences,” from memories of moments when they felt unbearable feelings such as fright, anxiety, shame, or pain. Back in France, pioneering psychologist Pierre Janet suggested that such “vehement emotions” caused patients to have “the evolution of their lives checked.” Although much of what was first known about the force of emotional memories came from studies of stress and trauma in women’s lives, two world wars soon brought male patients into the fold. American psychoanalyst Abram Kardiner’s writings on the “neurosis of war” are considered by many to be the seminal work on post-traumatic stress, setting the stage for the study of combat stress or the impact that war has on the psyche. “It is not like the writing on a slate that can be erased, leaving the slate like it was before. Combat leaves a lasting impression on men’s minds, changing them as radically as any crucial experience through which they live,” wrote American psychiatrists Roy Grinker and John Spiegel in 1945.

      From an evolutionary standpoint, it makes sense that we take special note of people, places, or situations that seem to threaten or benefit our survival; that there is enhanced memory for emotional experiences. Sometimes these emotional moments are especially happy ones, like sunny days spent riding the waves at the beach, or exciting ones, like watching crabs scamper around on the kitchen floor. Other times, they are distressing or frightening events, like watching a parent walk down the hallway and out of our lives. But while happy and exciting events enrich our experience of being alive, frightening events provide important information about staying alive, and so negative emotional memories tend to be more firmly installed in our minds. As psychology researcher Roy Baumeister summarizes in his often cited paper, “Bad Is Stronger than Good”: At least in our minds, “bad emotions, bad parents, and bad feedback have more impact than good ones, and bad information is processed more thoroughly than good.” This is because our brains are wired to keep us alive, not happy, and I doubt a single paper has been written about, nor a single therapy session devoted to, a client’s being unable to forget an extraordinarily joyful time. It is our shockingly upsetting experiences that are most deeply etched in our minds, and only in the last few decades have we come to better understand how the brain makes it so.

      In the chapters ahead, the region of the brain we will hear about again and again is the amygdala, or the part of the brain neuroscientist Joseph LeDoux calls the “hub in the wheel of fear.” A small almond-shaped region deep in the brain, the amygdala is a complex structure with many functions, but overwhelming evidence suggests it plays a central role in managing danger. When our senses detect disturbances in the environment—any potential physical or social threat—the amygdala is alerted, and within milliseconds it reacts. The amygdala is, again according to LeDoux, “where trigger stimuli do their triggering.”

      One key response that the amygdala triggers is the activation of the HPA axis, or the chain in the neuroendocrine system that consists of the hypothalamus, the pituitary gland, and the adrenal glands. When the HPA axis is stimulated, the adrenal glands release epinephrine, norepinephrine, and cortisol, hormones once commonly called adrenaline because they are produced by the adrenal glands and now more popularly and descriptively known as stress hormones because they help us adapt to stress. In our bodies, stress hormones prepare us for fight or flight, and in our brains, they heighten arousal, attention, and memory. Stress hormones tell our brains to wake up and pay attention, and tell our bodies to get ready to take action. They also tell our brains to remember what we see.

      Brain imaging studies show that when we look at intensely emotional material, such as slides of highly pleasant or unpleasant scenes, activity in the amygdala increases; and to some extent, the greater the activity in the amygdala, the better the recall is weeks later. Very low emotional arousal suggests there is nothing significant to pay special attention to, and so to protect our brains from overload, mundane events like showering or driving to work are not likely to be remembered in great detail or for very long. Our brains protect us from another sort of overload by sometimes failing to remember times when we are too emotionally aroused, especially those times that involve the utmost terror or helplessness. This is why victims of shark attacks or violent crimes, for example, may not remember such traumas at all; the events are too overwhelming to assimilate. Moderate stress, however, alerts us to threats in the environment that we perceive we can and should do something about. “There is nothing like a little stress to create strong, long-lasting memories of events,” says neurobiologist James McGaugh.

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