Early Stress Makes Child’s Brains Grow Up Too Fast, A sign to worry of

Since 1998, scientists in the Netherlands have been watching 129 people grow up. Over those 20 years, they observed and obsessively measured their patients’ brain matter. The results are in: What they found suggests that childhood stress may accelerate brain maturation, but that’s not necessarily a good thing.

Kids and teens are especially vulnerable.

Since 1998, scientists in the Netherlands have been watching 129 people grow up. Over those 20 years, they observed and obsessively measured their patients’ brain matter. The results are in: What they found suggests that childhood stress may accelerate brain maturation, but that’s not necessarily a good thing.

This research, published Friday in Scientific Reports, showed that the brains of people who had experienced stress in early life — like divorce or illness — were more likely to mature faster. To measure brain maturation, they tracked reductions in the volume of grey matter (GMV) — a cellularly dense tissue scattered throughout the brain. While it may sound counterintuitive that a brain gets smaller as it matures, the reduction is typical during adolescence, lead researcher Anna Tyborowska, P.h.D student and researcher at the Behavioral Science Institute (BSI) at Radboud University, tells Inverse. The general idea is that brains are born bigger than they need, but as life experiences highlight the essential parts, the less crucial bits get “pruned” away.

But there is one crucial catch: There is such a thing as maturing too soon.

“GMV increases during childhood and then starts to decline across adolescence,” Tyborowska tells Inverse. “Structures like the prefrontal cortex and amygdala, which are important for social-emotional processes, also mature during this time. These same structures are also rich in glucocorticoid receptors (stress hormones), which are activated by stress. Therefore, they are particularly susceptible to the effects of stress.”

Early Childhood Stress

The team looked at the link between brain matter and stress during their participants’ life periods: early childhood (age 1 to 5) and adolescence (14-17 years). In participants who experienced two or more early childhood stress events, Tyboroska and her team found that GMV decreased in the prefrontal cortex more than in those who didn’t. She hypothesised that this was due to premature brain maturation: Instead of waiting until adolescence to decline, the GMV in the stressed-out cohort reduced early. The effects of this, she says, are felt most in brain plasticity — the brain’s ability to adapt to changing stimuli.

The researchers hypothesise that there may be an evolutionary reason for pruning in response to early stress. Early life stress might prematurely set the process of brain maturation into motion to help ensure survival. But while a rapidly matured brain might have kept humans alive in leaner times, it may also have hampered brain plasticity — the brain’s ability to adapt.

“It is an adaptive mechanism at a time of heightened stress,” Tyborowska adds. “However, it can also prevent the brain from adjusting to the current environment given the developmental plasticity and flexibility typically afforded during adolescence. This, in turn, can lead to later costs for mental and physical health.”

Stress During Adolescence

People who experienced stress during adolescence — say, having low self-esteem in junior high or high school — had different changes in their grey matter. In participants who experienced stress during this period, GMV was estimated to increase in some portions of the brain, like the right anterior cingulate cortex. This area links the emotional limbic system and the “cognitive” thought mechanisms of the prefrontal cortex. Those who displayed these neurological changes were those who showed “un-emotional and callous traits” or “were disliked by their peers,” suggesting that stress during adolescence can shift brain development in ways that affect teens’ mental health.