ADHD, substance abuse and conduct disorder develop from the same neurocognitive deficits

August 12, 2014

Researchers at the University of Montreal and CHU Sainte-Justine Research Centre have traced the origins of ADHD, substance abuse and conduct disorder, and found that they develop from the same neurocognitive deficits, which in turn explains why they often occur together.

"Psychopathology exists on multiple continua of brain function. Some of these dimensions contribute to a multitude of , others contribute to specific problems. Together, they explain patterns of comorbidity such as why ADHD and conduct problems co-occur with at such a high rate," explained the study's lead author, Professor Patricia Conrod.

"Our findings suggest that risk for externalizing problems exist on a continuum in the general population, are easily measured and can be targeted before diagnosable problems arise. The findings also help reduce stigma and address some of the complexities when diagnosing and treating concurrent psychiatric problems. The implications are that clinicians can manage multiple psychiatric problems by focusing on how a young person is functioning on a fewkey neurocognitive dimensions. The next step is to develop evidence-based intervention strategies that will target these three areas of brain function"

The findings were established by studying the reward sensitivity and decision making patterns of 1,778 European 14-year-olds of comparable demographic profile. The teens were asked to undertake several tasks while undergoing an MRI and answer personality questionnaires. Clinicians also profiled the participants, once at the time of the testing, and again two years later.. At age 14, 4.4% of participants were identified as having a diagnosis of , ADHD, or both; by 16, this figure had risen to 6.6%. Alcohol and were also identified, with 3.7% and 10.6% prevalence respectively at age 14, and 18.0% and 27.1% respectively at age 16.

The researchers were able to use statistical modelling to see what risk factors were linked to which psychiatric symptoms. "This is the first study to model ADHD, conduct disorder and substance use problems in adolescence by using a novel statistical approach that identifies the shared variance among these problems as well as the neurocognitive risk factors that are common across these problems. Three key neurocognitive dimensions were identified as being implicated is most externalizing problems: impulsive action, impulsive choice (valuing immediate rewards over delayed rewards) and reward sensitivity. A young person's performance and on each of these dimensions were shown to be related to externalizing problems. Self report impulsivity, impulsive actions on a response inhibition task and the extent to which frontal brain regions are hypoactive when committing an impulsive action differentiated youth who were most at risk for ADHD and conduct problems from youth who are at risk for all externalizing behaviours more generally. Thrill or sensation seeking and abnormal activity in frontal brain regions when anticipating rewards differentiated youth who were uniquely at risk for alcohol misuse relative to those at risk for problems generally." explained Natalie Castellanos-Ryan, first author of the study. "There has recently been a trend in psychiatry to reformulate diagnostic categories from a dimensional and neuroscience perspective, fueled mainly by the high rates of comorbidity between certain disorders. This is precisely what we do with regards to externalizing disorders/problems. Our findings provide support for this new "dimensional" approach to psychiatric research by showing these disorder/problems share substantial variance as well as common and that they exist along a continuum in the general population."

The findings shed light on the cognitive deficits that could be targeted in order to potentially help treat comorbid cases (e.g. adolescents who have been diagnosed with both conduct disorder and substance use problems). "Comorbid cases are harder to treat and have worse prognosis than non-comorbid cases, and currently there are very few interventions or clinical strategies that are designed to treat comorbidity," Castellanos-Ryan said. "Prevention and intervention approaches for externalizing problems – ADHD, conduct disorder and substance use – could benefit from incorporating training components that target the brain functions or deficits related to impulsive action, impulsive choice, and reward sensitivity. Furthermore, these findings suggest that new intervention and prevention strategies targeting these deficits, either at the personality, cognitive or neural level, have the potential to concurrently impact on a number of clinical outcomes during adolescence and potentially before problems occur."

Explore further: Study details risk factors for substance use disorders after manic episode

More information: The research team published "Neural and Cognitive Correlates of the Common and Specific Variance Across Externalizing Problems in Young Adolescence" in the American Journal of Psychiatry on July 30, 2014. T

Related Stories

Study details risk factors for substance use disorders after manic episode

July 22, 2014
(Medical Xpress)—Adolescents with bipolar disorder are more likely to develop substance use disorders than adolescents without psychiatric disorders. Now, researchers at the University of Cincinnati (UC) have identified ...

Long-term study data supports association between childhood ADHD and substance abuse risk

May 31, 2011
Analysis of data from two long-term studies of the impact of attention-deficit hyperactivity disorder (ADHD) on the development of psychiatric disorders in young adults confirms that ADHD alone significantly increases the ...

Children with ADHD prone to substance use disorders

July 1, 2014
(HealthDay)—Screening for substance use disorders (SUDs) and the safe use of stimulant medications are important issues in the care of children with attention-deficit/hyperactivity disorder (ADHD), according to research ...

Children's impulsive behaviour is related to their brain connectivity

July 22, 2014
Researchers from the University of Murcia have studied the changes in the brain that are associated with impulsiveness, a personality trait that causes difficulties in inhibiting a response in the face of a stimulus and leads ...

Three hours is enough to help prevent mental health issues in teens

October 3, 2013
The incidence of mental health issues amongst 509 British youth was reduced by 25 to 33% over the 24 months following two 90-minute group therapy sessions, according to a study led by Dr. Patricia Conrod of the University ...

Large study shows substance abuse rates higher in teenagers with ADHD

February 11, 2013
A new study published online in the Journal of the American Academy of Child and Adolescent Psychiatry revealed a significantly higher prevalence of substance abuse and cigarette use by adolescents with attention deficit ...

Recommended for you

Depression changes structure of the brain, study suggests

July 21, 2017
Changes in the brain's structure that could be the result of depression have been identified in a major scanning study.

Many kinds of happiness promote better health, study finds

July 21, 2017
A new study links the capacity to feel a variety of upbeat emotions to better health.

Study examines effects of stopping psychiatric medication

July 20, 2017
Despite numerous obstacles and severe withdrawal effects, long-term users of psychiatric drugs can stop taking them if they choose, and mental health care professionals could be more helpful to such individuals, according ...

Study finds gene variant increases risk for depression

July 20, 2017
A University of Central Florida study has found that a gene variant, thought to be carried by nearly 25 percent of the population, increases the odds of developing depression.

In making decisions, are you an ant or a grasshopper?

July 20, 2017
In one of Aesop's famous fables, we are introduced to the grasshopper and the ant, whose decisions about how to spend their time affect their lives and future. The jovial grasshopper has a blast all summer singing and playing, ...

Perceiving oneself as less physically active than peers is linked to a shorter lifespan

July 20, 2017
Would you say that you are physically more active, less active, or about equally active as other people your age?

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.