It's no mystery that the brain develops before birth and continues throughout adulthood. But we may not have considered that brain development is analogous to building a house: laying the foundation, framing the rooms and installing electrical wiring. Obviously, laying a solid foundation builds a strong brain structure, while a weak foundation creates a faulty structure.

We are born with billions of neurons, the same number as adults. These specialized cells have to be connected or "wired" to form circuits to control different functions from basic to biological ones.

The most intense development occurs during the first three years. Over the past two decades, neuroscientists have gathered plenty of evidence that serious physical and sexual abuse during early childhood not only is emotionally damaging, but such abuse can also short-circuit normal brain development.

That abuse includes bullying.

Tracy Vaillancourt, a psychologist at the University of Ottawa, has conducted a range of studies into the emotional and psychological effects of bullying. In 2008, she found that bullied boys have higher levels of the stress hormone cortisol than their nonbullied peers, whereas bullied girls have much lower levels of cortisol compared with their peers.

So we have to wonder if experience external to our bodies can measurably change the physical properties of an organ so intrinsic to functioning as our brains.

Vaillancourt's long-term study involves following teenagers — some of whom have been bullied by their peers — and assessing their cognitive functioning every six months. She used magnetic resonance imaging (MRI) to scan the brains of the teens for evidence of damage to the hippocampus, the part of the brain that is involved in memory forming, organizing, and storing.

In a previous study, neuroscientist Martin Teicher scanned the brains of 63 young adults who reported being verbally bullied and found abnormalities in the corpus callosum, a region of the brain consisting of a bundle of fibers connecting the brain's left and right hemispheres, important in visual processing and memory.

Recently, a study showed strong evidence of an association between childhood maltreatment and the volume of cerebral gray matter. Joaquim Radua's study used a neuroimaging technique called voxel based morphometric (VBM) to compare the brains of 56 children and 275 adults who had a history of childhood maltreatment with 56 children and 306 adults who had no history of maltreatment.

Radua discovered that participants who had been exposed to maltreatment exhibited significantly smaller volumes of gray matter in several brain regions, possibly explaining why people with a history of child abuse are more likely to possess affective and cognitive deficits.

There is still much that neuroscientists need to sort out, such as cause and effect. However, these findings show the serious consequences of adverse childhood environments on brain development. Hopefully, the results of this latest study will help to reduce environmental risks during childhood and develop treatments to stabilize such morphologic alterations.