Rashomon Revisited—or How We Remember
The way in which we store our memories in the brain—and replay them over
time—is another important factor in how we are affected by childhood adversity.
Four siblings in a family can have four entirely different ideas about what
happened twenty years ago when Mom and Dad divorced, taking different sides
on the issue, rehashing their reasons for feeling the way they do. As in the movie
Rashomon
, each sees the events of the past differently, drawing different
conclusions.
Georgia says that when she and her sisters discuss their childhood, they can’t
agree on what growing up was really like. Georgia feels her sisters don’t validate
her experiences; they feel that Georgia overemphasizes the negative aspects of
life when they were kids, is still overreacting, and can’t let go of the past.
Some of this difference in how we remember is genetic; part of it is due to the
fact that each child in a family has different experiences within family life, and
some is also due to how the brain stores long-term memories and reshapes them
over time.
The brain’s ability to remember a fear or trauma response has been crucial to
the survival of our species. As our ancestors evolved, they had to be able to
remember, for instance, that certain berries are toxic and make them sick. So
they made a lifelong association between the berry and severe illness. Every
time they saw that red berry, they thought, don’t eat it, you could die.
When we have suffered Chronic Unpredictable Toxic Stress, simply
remembering a person or event that was hurtful or humiliating may trigger us to
relive that earlier hurt in vibrant detail—and cause us to experience a similar
deep-fear response again. We don’t want to be reexperiencing that stress, and yet
all too often our worst memories are those we recall the most.
Why are these memories so potent, even when we don’t want them to be?
Specific hormones dramatically change developing brain synapses when we
feel fear, love, or rage. When something traumatic occurs, the hormone
noradrenaline—the brain’s equivalent of adrenaline—alters the chemical and
electrical pathways in the areas of the brain responsible for memory formation.
These hormones trigger a complex biochemical process in which the brain
captures, stores, and encodes these traumatic memories—a process
neuroscientists refer to as “consolidation.” That’s why our most robust human
memories—our vivid autobiographical snapshots from childhood—are
associated with strong emotional events during which we felt potent fear,
anxiety, love, humiliation, or rage.
Most people consider powerful memories to be like snapshots or video clips
that we can review and replay, and assume our memories are a true rendition of
the past.
But those captured memories actually get revised all our lives. Even after a
memory has been consolidated—encoded and stored in our amygdala and
hippocampus—it doesn’t
stay
consolidated. Our brain rewrites those memories
over time, based on new information and experiences. Each time we remember
an incident of childhood adversity, that particular memory becomes labile, or
susceptible to changes in how and what we remember about what happened.
Neuroscientists call this process “memory reconsolidation” because we
continually update and revise our existing memories as time goes by. We rewrite
some details based on new input, erasing others. And yet, that memory is always
encapsulated by the same feelings we felt when the experience first occurred, at
whatever age we were at the time. For instance, each time Harriet recalls how
her grandfather forced her into the bathtub, she reexperiences that five-year-
old’s feeling of vulnerability, that same terrible sense of rage, helplessness, and
shame she felt then. When we mentally revisit an event, we are always that
young age.
Without realizing it, we make a lot of our life decisions based on powerful,
key life memories. Big events become family stories of moral import passed
down from generation to generation, affecting family dynamics. Families can
even break down and break apart over differing ideas of what happened decades
ago, and who was to blame. We learn not to be taken advantage of in business
because of what Uncle so-and-so did to our mom. We avoid certain types of
people and situations because of the time our dad had that incident in his youth
that he tells us changed the trajectory of his life.
But to some degree, memory plays hoaxes on us all. The thing you are so very
certain about—the black stiletto heels your mother was wearing on the fateful
day she told you she was leaving your father—may not have been black stilettos
after all. You simply added that detail years later, based on later input; on
another occasion when she was angry with you and yelling, she was wearing
black heels. You’ve rewritten your earlier memory to add in “stiletto heels.”
You’ve layered more onto the original memory.
Our brains construct a world that no one else can see, touch, or hear. Or, as
Buddhist teachers sometimes say, “The truth is a pathless land.”
This is not to say that your memories are wrong, or that you are wrong to put
great store in them. But you are not the same person you were yesterday,
because what happened yesterday changes you. And it even changes how you
perceive what happened forty years ago.
We store memories in two ways: in explicit or implicit memory. “Explicit
memory” is the recollection of specific events, details, concepts, and ideas. The
greater the sense of danger or pain, the more neurons fire and wire together,
registering an experience in an explicit memory.
An “implicit memory” is the emotional sense of how events have made us
feel; it’s our gut response when we think about something. Many kids who’ve
faced childhood adversity carry forward implicit memories from the first few
years of life—when they were too young to even remember the explicit details
of what happened. Harriet, for instance, recently found hospital records that
showed that she was hospitalized for “dehydration” during her first two years of
life—multiple times. She doesn’t remember those hospitalizations, or feeling
thirsty, or weak and dehydrated, but finding these documents helped her to
understand why she had such a visceral sense that her mother never protected
her or kept her safe. The implicit memory that she was in danger is there, along
with all the explicit memories that she recalls from growing up with her mom.
Indeed, in understanding childhood adversity, the accuracy of who was
wearing what or where people were standing is far less important than the fact
that something emotionally or physically harmful happened that caused the
inflammatory stress response to kick in.
Kat was five when she saw her mother on her father’s office floor, and has
recalled that scene thousands of times in her life. She knew what happened.
Even if over the years she started to reimagine her mom’s shoes in a different
color, she still knew what had happened. The scene was not less true. She felt,
deep within, the bigger picture of what was taking place.
Early memories of raw, emotional intensity cause neurons to wire and fire
together, and they get tweaked continually over time. These memories have a
potent draw on us all our lives, and we revisit and think about that thing that
happened when we are eleven throughout our lives—when we are thirty, or
forty, or even sixty-five.
As the Buddhist teacher Thich Nhat Hanh says, “There is a tendency to want
to go back to the past. Regret and sorrow are always there to draw us back.”
Yet, instead of getting caught in replaying mental videos of what happened in
the past, we need to work it through so that we don’t imbue that past adversity
with more emotional content over time. Working through these memories is
important because strong memories condition us to be on alert for similar
situations in the future—which means we’re always on alert, watching for the
next adverse situation in which we might be made to feel the same way we felt
as children. We’re consciously and unconsciously looking for more information
in order to reconsolidate that memory, continually updating our understanding of
how and when and why such situations represent danger.
That can be a real problem, because the brain’s alert center, the amygdala,
operates much faster than the brain’s cortex. It takes two hundred milliseconds
for the amygdala to compute, based on our past memories, whether to trigger
fight or flight, compared with three to five seconds for the cortex to make a more
judicious decision and weigh what’s happening—which means our memories
can influence us to have a knee-jerk reaction before we think. If your boss is
wearing the same perfume that your narcissistic, borderline mother wore, or if
she wears black high heels that click in the same way as your mom’s did on the
parquet floor, or if she’s a bit hypercritical in a way that reminds you of your
mother’s passive-aggressive jabs, your brain is going to sense danger, register
fight or flight, and you’re going to have trouble reacting to your boss as your
boss.
Our brain is hyperbusy looking for confirmation that the world is a scary and
dangerous place, and so are the people in it. We begin to overgeneralize our
fearful memories, which can lead to generalized anxiety, worsening our set point
of well-being.
When you are drawn back again and again into the past without taking steps
toward healing, recovering from childhood wounds can prove difficult, if not
impossible. Exploring your adverse experiences, telling your story, in order to
understand and better work through the past, is a crucial step in healing.
The good news is that, as we will see in Chapter Seven, researchers have been
using this new understanding of the constantly evolving process of
reconsolidating our past memories to understand how we might revisit painful
memories in ways that finally remove their power over us. We can become more
like those centenarians that Harvard researchers studied, who wavered under the
weight of life’s suffering, grieved for their losses, and then moved on with their
lives.
Meanwhile, as we will see in the next chapter, among the many factors that
affect how Adverse Childhood Experiences will influence your body and brain,
perhaps the most important one of all is the sex that you were born.
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