Growing up in poverty or experiencing early childhood adversity, such as abuse or neglect, can put a child at risk of poor health, including mental health disorders, later in life. Although the underlying mechanisms are poorly understood, several studies show that adverse childhood experiences leave lasting (and possibly irreversible) imprints on brain structures.
As neuroscientists who study sensitive periods of human brain development, we agree that a safe and nurturing environment is a prerequisite for healthy brain development and lifelong well-being. Therefore, preventing childhood adversity definitely leads to a healthier life.
Poverty and adversity can cause changes in brain development. Harm can result from exposure to violence and toxins, nutrition, caregiving, sensory and cognitive stimulation, and lack of verbal interaction. Neuroscientists have demonstrated that these factors critically influence human brain development.
However, we do not know if these changes would be reversed by more favorable circumstances in later years. This question is very difficult to investigate in humans. First, it is difficult to unravel the multiple biological and psychological factors by which poverty and adversity affect brain development. This is because they often occur simultaneously. Abandoned children often experience a lack of nurturing as well as exposure to malnutrition and physical violence. Second, it is difficult to define a clear beginning and end for adverse experiences. Finally, it is almost impossible to completely reverse the harsh conditions in the natural environment, as it is almost impossible to separate children from their families and communities.
In a recently published study, cerebral cortex, we and colleagues investigated the reversibility of changes in brain structure in individuals who regained their sight after suffering from congenital blindness. Visual deprivation can be considered an extreme form of abnormal childhood experience, and congenital blindness is known to cause a reduction in brain surface area similar to other types of abnormal childhood experience.
This joint German-Indian study used non-invasive magnetic resonance imaging (MRI) to examine the structure of the cerebral cortex. The cerebral cortex is the folded outer layer of the brain that is home to billions of nerve cells and oversees perception, behavior and higher order thought. In our study, 21 individuals aged 6 to 36 years at the time of the study who were born blind due to dense bilateral cataracts and gained vision by cataract removal surgery only months or in some cases years later We studied children and adults. Cataracts are the most common cause of treatable blindness worldwide. In Western countries, newborns born with cataracts usually undergo surgery shortly after birth. However, in many resource-poor countries, cases often go untreated for years. Inverted cataract patients can be completely cleared of the cause of their blindness at a well-defined point in their lives, making them a unique human being for assessing the reversibility of impaired brain structures after abnormal childhood experiences. Configure your model. Previous research suggests that despite vision-restoring surgery, people whose congenital blindness is delayed in treatment usually do not regain full visual ability and remain visually impaired for the rest of their lives.
In our recent study, a person with inverse congenital cataract was identified by the LV Prasad Eye Institute, Hyderabad, India. They had been blind for an average of 7 years and had had cataract removal surgery 11 years before the study. We compared this group to his three others. Vision-impaired individuals who were born sighted and later developed cataracts. and visualized controls. A three-dimensional model of each participant’s brain was created from brain scans and used to measure the surface area and thickness of the cerebral visual cortex.
We examined the visual portion of the cerebral cortex to understand how early experiences shape the brain during development. In typical brain development, cortical surface area expands until puberty, while cortical thickness increases during the first two years of life and then decreases. This initial increase in cortical thickness is thought to reflect the explosion of connections between synapses, or neurons, while subsequent thinning reflects the pruning of unused connections. It is believed that Structural changes are essential for the refinement and maturation of neural circuits.
In our study, we observed that patients with reversed congenital cataracts had a smaller visual cortical surface area and a thicker thickness compared to sighted individuals of their respective ages. Despite many years of visual acuity recovery, those who recovered had visual cortices that closely resembled the corresponding visual cortices of those with permanent blindness. Similar changes were not detected in patients with reversed cataracts that developed later in childhood. Importantly, the degree of structural impairment predicts how well a patient has learned to see.
These results suggest that brain structures damaged by aberrant experiences in early childhood are not fully recovered by restoring typical experiences later in life. Unlike the local effects of blindness on visual regions of the brain, the effects of poverty and adversity are often much more widespread throughout the brain, probably due to the combined effect of multiple biological and psychological hazards. It is considered to be due to Therefore, based on our recent findings, we would expect that experiencing harsh environments early in life would result in irreversible structural changes in multiple regions of the brain, which may explain why these individuals are suffering from mental disorders. It may explain how susceptible you are to ill health, including
This new finding highlights the important role of preventive measures in promoting healthy brain development in children. Ensuring access to a safe environment, affordable health care, healthy diets and appropriate education gives children the opportunity to develop and maintain physical and mental health.
This is an opinion and analysis article and the views expressed by the author are not necessarily those of the author. Scientific American.
