The Neural Substrates of Emotional Attention and Inhibition Across Adolescence

Lay Summary

Imaging the Teen Brain To Understand Emotional Development and Vulnerability To Mood Disorders

Brain regions involved in emotional responsiveness and regulation during adolescence will be imaged with fMRI to examine the influence of age and pubertal hormone levels on these developing brain systems and on adolescents’ potential vulnerability to mood disorders.

Adolescence, a time of considerable brain maturation and behavioral change, is also accompanied by a notable increase in emotional intensity.  While parents traditionally sigh and say “hormones,” little is currently known about the cascade of developmental processes triggered by pubertal hormones.  Improvements in executive functioning parallel prefrontal cortex development, and begin in puberty and continue throughout adolescence.  Increases in emotional responsiveness, risk-taking and novelty-seeking behaviors, in contrast, are likely associated with the early influences of pubertal hormones on the brain.

The Oregon investigators hypothesize that regulatory (executive functioning) brain systems develop during the later teen years as a function of age and experience, while emotional systems activated by pubertal hormones occurs in early adolescence, and that this juxtaposition of  regulatory and emotional development may help to explain the rise in depression in this age group.

They will use fMRI to examine the neural systems of emotional attention (limbic system) and inhibition (prefrontal cortex) in 35 female and 35 male adolescents between the ages of 10 to 15, and examine the respective influences of age and pubertal hormones on these developing brain systems.  They will correlate these imaging findings with endocrine and psychological measures.

Abstract

The Neural Substrates of Emotional Attention and Inhibition Across Adolescence

Adolescence is a time of considerable neuromaturation and behavioral change.  While the development of sophisticated inhibitory and regulatory functions is paralleled by late maturation of prefrontal brain regions, early increases in adolescent emotionality and risk-taking appear to coincide with the activation of limbic structures and associated rise in gonadal hormone levels during puberty.  Given that studies of intact emotional inhibition in adults suggest top-down control of affective limbic systems by regulatory prefrontal systems in the brain, the immaturity of this network during early adolescence may contribute to increased emotionality and may explain rising rates of depression during the teen years.

To better understand this vulnerability, this cross-sectional study will examine the unique influences of adolescent age and gonadal hormone levels on the neural substrates of emotion.  Specifically, the proposed study will use functional magnetic resonance imaging (fMRI) methods to examine the neural substrates of emotional attention and inhibition in 70 healthy 10-15-year-old youth and will examine the respective influences of age and gonadal hormones on these developing neural systems.

Understanding these relationships may help to explain adolescent and sex-specific vulnerability to depression and may ultimately permit the development of strategies aimed at reducing mood disorders that are targeted at specific age and risk groups.