Understanding Adolescent Brain Development: A time of change - a period of vulnerability and opportunity Michael L. Lindsey, JD, PhD Nestor Consultants, Inc. Dallas, Texas

In order to understand adolescent development... We must understand development in the context of one’s whole life, i.e., the factors that place our youth at risk, and those factors that protect them

Adolescent’s maturity cycle Bigger Stronger Faster Improved reasoning ability Increased ability to tolerate environmental stressors

Increased rates Accidents Suicide Homicide Assaults/violence Depression Alcohol and substance abuse

The adolescent mind works differently Emotional instability Over valuing of short term benefits Reckless risk-taking Impulse control Experimentation with sex Experimentation with drugs Misattribution of affect

Until recently many scientists believed that the brain was largely a finished product by age 12, as well as completed cognitive development (Formal Operations). Studies have since proved that both gray and white matter undergo extensive changes well past puberty

Brain Development The brain develops in a predictable fashion (primitive to most complex) Sensitive periods are “windows of vulnerability” – most affected by environmental impact

brain's plasticity in action. But not all parts of the brain are equally plastic       

     

Brain Growth Humans achieve maximum brain-cell density between the 2 nd and 3 rd month of gestation. During the final months before birth our brains undergo extensive pruning of unnecessary brain-cells. A second wave of pruning occurs during adolescence that affects our higher mental functions. This pruning impacts the number and quality of connections between cells.

Change in amount of gray matter, and white matter reflecting change in size and complexity of neurons Maximal thickness for girls at age 11 and for boys age 12 Brain of 8 year old is different than a 13 year old During pruning, connections that are used will survive and strengthen; those not used will atrophy

Executive Functions- Frontal Cortex Planning Setting Priorities Organizing thoughts Suppressing impulses Weighing the consequences of our actions

Adolescent Brain Higher cognitive processes not fully matured Processing speed less efficient including working memory Integration less than optimal for supporting top-down cognitive control of behavior

Puberty and Brain Development Some brain changes precede pubertal changes Some brain changes are the consequence of pubertal changes Some are totally independent of pubertal changes

The past 150 years are noted by a quiet revolution in human development; children generally are growing faster, reaching reproductive and physical maturity at earlier ages, and achieving adult physical development sooner than at anytime in history

Raging Hormones As the brain shifts from expanding neural connections to pruning, the body also experiences the onslaught of puberty. The parts of the brain responsible for sensation seeking are becoming more activated, and the parts responsible for impulse control are under construction

Puberty and motivation/emotion Strongest link to pubertal changes are in romantic motivation, sexual interests, emotional intensity Increased risk taking, sensation-seeking and novelty seeking

Adolescents are not children but also not adults

Some adolescents enter this transitional period with poor regulation and affect tolerance skills. They do not have what is required to negotiate the challenges, particularly those in high risk, low supportive environments.

Adolescence ~ Summary Thoughts Establishes new links between more complex ways of thinking and access to emotions as a resource Opportunities for intervention and prevention in high risk populations Increased understanding of both normal and deviant patterns entering and leaving transition to young adulthood