A recent study published in JAMA Psychiatry found that some adolescents, especially males, who lived in disadvantaged neighbourhoods showed abnormal changes in brain structure from early to late adolescence.
Positive parenting may protect against changes in brain structure, counteracting the biological and functional consequences associated with disadvantage. The biological, psychological, and social consequences of socioeconomic disadvantage have been well documented across the life span. In particular, a disadvantage has been associated with alterations in brain development, although not all children or adolescents who experience disadvantage display alterations. Environmental factors may protect them from neurobiological damage, explaining why some experience alterations and others do not. Positive parenting may help to explain these differences, protecting children and adolescents from neurobiological alterations that negatively impact lifelong functioning.
In a recent longitudinal study published in JAMA Psychiatry, researchers investigated the potential protective effect of positive parenting on the relationship between socioeconomic disadvantage and adolescent brain development. They also examined the association between brain development measured across the adolescent years and adolescents’ global and academic functioning. Family-level and neighbourhood socioeconomic disadvantage was assessed, as previous research has shown differential effects of disadvantage on developmental outcomes depending on the measure used. The researchers also tested for sex-specific differences in all analyses.
The study was conducted using data previously collected from 166 Australian adolescents aged 11 to 20 years. The adolescents completed magnetic resonance imaging (MRI) scans 1 to 3 times over the study period, at average ages of 13, 17, and 19 years, to assess changes in brain structure. Parental occupation, educational level, and income-to-needs ratio (i.e., income relative to Australian poverty line for household size) were used as measures of family socioeconomic disadvantage. Neighborhood disadvantage was measured using a regional socioeconomic index based on economic and social indicators specific to small geographical regions. The researchers assessed positive parenting by observing and coding video-recorded mother-adolescent interaction tasks. Positive parenting behaviours were characterized by happy or caring effect, as well as approval, validation, affection, or humor expressed with neutral affect.
Only neighbourhood socioeconomic disadvantage was associated with changes in brain structure from early to late adolescence. Adolescents, especially males, who lived in more disadvantaged neighbourhoods showed alterations in the amygdala and frontal cortex.While parenting behaviours influenced the relationship between both family-level and neighbourhood disadvantage and brain structure, positive parenting exerted a protective effect for adolescents experiencing high levels of neighbourhood disadvantage. Disadvantaged adolescents whose mothers displayed more positive parenting behaviours showed frontal and temporal lobe structure similar to adolescents with lower levels of disadvantage. The combination of high levels of disadvantage and less positive parenting was especially detrimental for males who showed alterations in brain structure, as these alterations predicted higher rates of school noncompletion.
While this study was limited by single assessments of parenting behaviour and socioeconomic disadvantage, as well as the use of two MRI scanners, it provides the first evidence that positive parenting might shield disadvantaged adolescents from the detrimental effects of changes in brain structure. It calls attention to the effect of neighbourhood disadvantage on brain development, suggesting that this effect is particularity pronounced for males. Further research is needed to explore the male-specific nature of the findings; given the immaturity of some brain regions in males compared to females, these regions may be more likely to respond to positive environmental influences. As not all changes in the brain regions studied were associated with functional outcomes like school completion, more research is needed to study these associations and the mechanisms that drive them.
Written By: Suzanne M. Robertson, Ph.D
Reference: Whittle, Sarah, et al. “Role of Positive Parenting in the Association Between Neighborhood Social Disadvantage and Brain Development Across Adolescence.” JAMA psychiatry (2017).