People Who Grew Up In Difficult Homes Often Experience These 7 Lasting Brain Changes
Freeman Studio | ShutterstockGrowing up in a difficult home can change the brain in lasting ways.
If you've ever wondered why you've been struggling a little too hard for a little too long with chronic emotional or physical health conditions that just won't let up, a growing field of scientific research may offer hope, answers, and a better way to understand what happened. In 1995, physicians Vincent Felitti and Robert Anda launched a large-scale study that examined the childhood histories of more than 17,000 people and compared their early experiences with their adult health records. The results showed that Adverse Childhood Experiences, often called ACEs, were linked to a higher risk of stress-related physical and mental health problems later in life. Now, neuroscientists are learning more about how growing up in a difficult home can affect the brain, the body, and the way people respond to stress for years after childhood ends.
Here are 7 brain changes people may experience after growing up in a difficult home:
1. Their stress response may stay stuck on high
When we're repeatedly thrust into stress-inducing situations during childhood or adolescence, our physiological stress response shifts into overdrive, and we lose the ability to respond appropriately and effectively to future stressors, 10, 20, even 30 years later.
This happens due to a process known as gene methylation, in which small chemical markers, or methyl groups, attach to the genes involved in regulating the stress response, preventing them from doing their jobs. As the function of these genes is altered, the stress response is reset to "high" for life, promoting inflammation and disease.
This can make us more likely to overreact to the everyday stressors we encounter in our adult lives: an unexpected bill, a disagreement with a spouse, or a car swerving in front of us on the highway, thereby creating more inflammation. This, in turn, predisposes us to a host of chronic conditions, including autoimmune disease, heart disease, cancer, and depression.
Yale researchers found that children who'd faced chronic, toxic stress showed changes "across the entire genome," in genes that not only oversee the stress response but also in genes implicated in a wide array of adult diseases.
This new research on early emotional trauma, epigenetic changes, and adult physical disease breaks down longstanding delineations between what the medical community has long seen as "physical" disease versus what is "mental" or "emotional."
2. Certain areas of the brain may become smaller or work differently
When the developing brain is exposed to chronic stress, the body's stress response can remain activated for too long, releasing stress hormones such as cortisol. Research suggests that childhood maltreatment and higher ACE scores may be associated with reduced gray matter volume in brain regions involved in memory, decision-making, emotion, and fear, including the hippocampus, prefrontal cortex, and amygdala.
Kids whose brains have been altered by Adverse Childhood Experiences are more likely to become adults who overreact to even minor stressors.
3. They may be more likely to struggle with mood disorders
A. C. / Unsplash+
Children have an overabundance of neurons and synaptic connections; their brains are hard at work, trying to make sense of the world around them. Until recently, scientists believed that the pruning of excess neurons and connections was achieved solely in a "use-it-or-lose-it" manner, but a surprising new player in brain development has appeared on the scene: non-neuronal brain cells known as microglia, which make up one-tenth of all the cells in the brain and are actually part of the immune system, participate in the pruning process.
These cells prune synapses like a gardener prunes a hedge. They also engulf and digest entire cells and cellular debris, thereby playing an essential housekeeping role.
When a child faces chronic, unpredictable stress, research suggests it may affect microglia, the brain's immune cells that help shape developing neural circuits. Studies have linked early-life stress to changes in microglial function, which may play a role in neuroinflammation and later problems with mood, memory, and stress regulation.
That means that kids who come into adolescence with a history of adversity and lack the presence of a consistent, loving adult to help them through it may become more likely to develop mood disorders or have poor executive functioning and decision-making skills.
4. Their cells may show signs of faster aging
Early trauma can make children seem "older" than their peers, and research suggests Adverse Childhood Experiences may also age them at the cellular level.
Adults who'd faced early trauma show greater erosion of telomeres, the protective caps at the ends of DNA strands, like the caps on shoelaces, that help keep the genome healthy and intact. As our telomeres erode, we're more likely to develop the disease, and our cells age faster.
5. They may have trouble figuring out what's safe and what isn't
Inside each of our brains, a network of neurocircuitry, known as the "default mode network," quietly hums along, like a car idling in a driveway. It unites brain regions associated with memory and thought integration, and it's always on standby, ready to help us figure out what we need to do next.
"The dense connectivity in these areas of the brain helps us to determine what's relevant or not relevant so that we can be ready for whatever our environment is going to ask of us," explains Ruth Lanius, a neuroscientist and PTSD researcher at the University of Ontario.
But when children face early adversity and are routinely thrust into a state of fight-or-flight, the default mode network starts to go offline; it's no longer helping them to figure out what's relevant, or what they need to do next.
According to Lanius, kids who've faced early trauma have less connectivity in the default mode network, even decades after the trauma occurred. Their brains don't seem to enter that healthy idling state, so they may have trouble responding appropriately to the world around them.
6. Their emotional stress may show up as physical pain or illness
Until recently, it was widely accepted that the brain is "immune-privileged," or cut off from the body's immune system. But that turns out not to be the case, according to a groundbreaking study conducted by researchers at the University of Virginia School of Medicine.
Researchers found that an elusive pathway travels between the brain and the immune system via lymphatic vessels. The lymphatic system, part of the circulatory system, carries lymph, a fluid that helps eliminate toxins, and moves immune cells from one part of the body to another. Now we know that the immune system pathway includes the brain.
The results of this study have profound implications for ACE research. For a child who's experienced adversity, the relationship between mental and physical suffering is strong: the inflammatory chemicals that flood a child's body when she's chronically stressed aren't confined to the body alone; they're shuttled from head to toe.
7. They may have a higher risk of anxiety and depression
University of Wisconsin researcher Ryan Herringa found that children and teens who'd experienced chronic childhood adversity showed weaker neural connections between the prefrontal cortex and the hippocampus. Girls also displayed weaker connections between the prefrontal cortex and the amygdala.
The prefrontal-cortex-amygdala relationship plays an essential role in determining how emotionally reactive we're likely to be to the things that happen to us in our day-to-day life, and how likely we are to perceive these events as stressful or dangerous.
According to Herringa, "If you are a girl who has had Adverse Childhood Experiences and these brain connections are weaker, you might expect that in just about any stressful situation you encounter as life goes on, you may experience a greater level of fear and anxiety."
Girls with these weakened neural connections, Herringa found, stood at a higher risk for developing anxiety and depression by the time they reached late adolescence. This may be one reason girls with high childhood adversity face a higher risk of anxiety and depression later in life.
This science can feel heavy, especially for parents or anyone who recognizes their own childhood in it
The good news is that, just as our scientific understanding of how adversity affects the developing brain is growing, so is our scientific insight into how we can offer the children we love resilient parenting, and how we can all take small steps to heal body and brain.
Just as physical wounds and bruises heal, just as we can regain our muscle tone, we can recover function in under-connected areas of the brain. The brain and body are never static; they are always in the process of becoming and changing.
Donna Jackson Nakazawa is an award-winning researcher, writer, and public speaker on health and family issues.
