Brain Development During Adolescence

Synaptogenesis is a hallmark of brain development that involves synapse formation between neurons in the nervous system. While it occurs throughout an individual’s lifetime, there is a surge of synaptogenesis during infancy and a second during adolescence, which facilitates learning, memory, and adaptation. MRI studies have demonstrated a surge of neuronal growth and thickening of the grey matter in the brain right before puberty, similar to neuronal growth during infancy. Crucial developmental changes occur in a young person’s brain that are incomplete until around age 25. While there is no set age range to define adolescence, it is generally described as a time including puberty and teenage years and a transition from childhood into adulthood. In terms of brain development, some researchers define adolescence as the time between age 10 and 24.

The brain plasticity of adolescence allows a time for intellectual and emotional growth, an ability to adapt, and acts as a time to develop lifelong interests, talents, and passions. Dopamine, serotonin, and melatonin are 3 neurotransmitters that play a major role in adolescent behavior and produce both positive and negative emotions and reactions. Impulse control is impacted by decreased levels of serotonin, earning teenagers the reputation of being risk-takers. Taking risks is a part of growth and personal development, but when these risks involve drug and alcohol abuse, oftentimes it is no longer a method of temporary self-exploration but an action that can have serious and long-time effects on brain development.

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Drug Use During Brain Development

Due to the neurodevelopmental processes that occurs during adolescence, teenagers are more likely to take risks, including drug use, than children and adults according to research published by the National Institutes of Health. This drug use can be particularly dangerous, as drug use as an adolescent significantly increases the risk of developing a substance use disorder later in life. Some research has found that the earlier the onset of drug use, the higher the chance that a person will develop a drug problem. When drug use and other negative occurrences, like trauma and chronic stress, take place during early brain development, this can have a damaging impact on brain maturation.

When someone uses certain drugs, the substances flood the brain with dopamine. Dopamine is the neurotransmitter often referred to as the “feel good” neurotransmitter, as it plays a large role in feelings of pleasure. When the brain is overloaded with dopamine because of a drug, the brain responds by producing less dopamine naturally. With continued drug use, a person may be unable to feel happy without their drug of choice. Depending on the substance and frequency of use, it can take hours or weeks for the brain to regain balance.

Alcohol Abuse During Brain Development

Among American youth, alcohol is the most widely abused substance. In fact, over 29% of teens have already tried alcohol by age 15. Young people drink in larger quantities than adults, with 90% of the alcohol consumed by young people being alcohol consumed via binge drinking. Binge drinking is defined as a female having 4 or more drinks within a 2-hour period, and a male having 5 or more drinks within a 2-hour period. Drinking heavily during adolescence should not be considered a normal part of growing up, as it can come with serious and long-term effects.

Research by the EEG and Clinical Neuroscience Society found that, “Abnormalities have been seen in brain structure volume, white matter quality, and activation to cognitive tasks, even in youth with as little as 1–2 years of heavy drinking and consumption levels of 20 drinks per month.” The critical period of brain development in youth may be interrupted by alcohol abuse, and cause issues later in life related to academic, occupational, and social functioning. Drug and alcohol abuse may also put people more at risk for mental health disorders and risky sexual activity. Some research has suggested that heavy alcohol abuse can reduce the size of the hippocampus; the part of the brain that is involved in the formation of memories as well as learning.

In one study examining alcohol, Marijuana, and stimulant use among youth, the youth with a history of light drinking performed better on cognitive tasks than youth with a history of heavy drinking. Those who had displayed alcohol withdrawal symptoms like nausea and irritability had decreased performance skills, primarily on tests of spatial functioning. Another study found that the prefrontal cortexes of adolescent drinkers were smaller in heavy drinkers, compared to non-drinkers. This difference was especially pronounced in females. Animal studies have also demonstrated long-lasting changes in functional brain activity when adolescent rats were administered ethanol vapors.

Substance Abuse Treatment For Youth

Many adolescents take unnecessary risks and make decisions that can be difficult for the adults in their lives to understand. While a young person needs the freedom to start making their own choices and figuring out who they want to be, it is important to intervene when drug and alcohol abuse become present. A professional diagnosis that examines any underlying mental health disorders and understands their pattern of abuse is crucial for formulating the most appropriate treatment option for each individual. Early intervention can make a world of difference during a time when youth are so susceptible, and it could prevent the development of a substance use disorder later in life. Contact a treatment provider to find out more about treatment options for people of all ages.

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Dr. Ashish Bhatt

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  • Dr. Ashish Bhatt, MD, MRO is an accomplished physician, addiction medicine specialist, and psychiatrist with over 20 years of medical and administrative leadership.

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