Conduct Disorder: Predictors, Gender and Genetics

Genetic factors contribute to risk for many childhood mental disorders.

Gender issues in childhood psychopathology are also important factors.

Boys show higher rates for conduct disorder (CD), oppositional defiant disorder (ODD) and attention deficit hyperactivity disorder (ADHD).

Nora Kerekes and colleagues in Sweden and Australia examined a large twin study of childhood behavioral and neurobehavioral disorders. The aims of this study were to better understand the developmental and genetic features with attention to gender issues.

Key features of design of this study included:

• Twin status identical (monozygotic-MZ) vs fraternal (dizygotic-DZ) was assigned via algorithm and saliva samples
• Clinical features were assessed using the Autism-Tics, AD/HD and other Comorbidities inventory
• Data analysis included descriptive statistics and twin gene-environment modelling

As expected, ODD and CD rates were higher in boy twins than in girl twins. For ODD the boy:girl prevalence rates were 3.5%:2.1%. For conduct disorder the boy:girl prevalence rates were 1.3%:0.6%.

The research team found two distinct neurodevelopmental predictors. Early concentration/attention problems led to an increase in later ODD in both boys and girls. Additionally, early social interaction problems was linked to increased CD rates in both genders.

Higher monozygotic versus dizygotic twin concordance rates indicate a significant genetic contribution. The original figure above shows the MZ v DZ rates for the boy twins abstracted from the manuscript. All three behavioral disorders as well as autism spectrum disorder (ASD) showed significant genetic contributions in the boy twins.

For girl twins a genetic contribution was identified for ODD, ADHD and ASD. Of note, CD rates were not increased in MZ girl twins compared to DZ girl twins.

The authors note their findings have clinical implications including:

• Clinicians need to be aware of the differences between boys and girls with ODD and CD
• Inattention problems are important but less evident that behavioral problems. Clinicians should be diligent in looking for attentional problems in girls as a risk for later CD
• Social interaction problems are common predictors and common comorbid features in ODD and CD
• Treatment of ODD and CD in both boys and girls should include family interventions with multimodal interventions targeting improvement in "social interaction and communication abilities".

This is an important study that emphasizes a comprehensive surveillance and assessment program for behavioral problems in both boys and girls.

Readers with more interest in this study can access the free full-text manuscript by clicking on the DOI link in the citation below.

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Kerekes, N., Lundström, S., Chang, Z., Tajnia, A., Jern, P., Lichtenstein, P., Nilsson, T., & Anckarsäter, H. (2014). Oppositional defiant- and conduct disorder-like problems: neurodevelopmental predictors and genetic background in boys and girls, in a nationwide twin study PeerJ, 2 DOI: 10.7717/peerj.359

How Video Games Reward the Brain: TED Video

Tom Chatfield provides an overview of how games stimulate brain reward processing. Chatfield is game enthusiast who edits the arts and books section of the UK magazine, Prospect.  Here are my notes from the TED video.
 

Chatfield begins by stating he is in awe of the power of virtual games to transfix us.

Video gaming is the fastest growing of all forms of media ($50 billion per year).

People spend enormous time and money on virtual game rewards.  Farmville has over 70 million players around the world.

The good news is this gaming teaches us about brain rewards.

Video games produce huge data sets of reward processing.

We have evolved in special ways. Here are seven ways games teach us about brain rewards.

1. Measuring progress aids reward-games use constant score updating to reward players
2. Multiple long and short-term gains--by adding complexity, gamers are less likely to become bored
3. Reward for effort-every time you get something for effort, negative feedback is not very helpful
4. Feedback is frequent, rapid and clear
5. Element of uncertainty- uncertainty of reward is a neurological and psychological gold mine.  Dopamine is the brain's reward learning chemical and is released more with unexpected reward
6. Windows of enhanced engagement-in gaming, developers use moments of enhanced memory and increased confidence
7. Social interaction-playing with other people enhances reward and is more likely to keep gamers involved in the game

These principles have implications in business.  Real time energy meters could provide immediate feedback on progress in saving energy.

Implications are important for education.  We can use game technologies to enhance learning.

Finally, in government we may learn how to reward people to change complex behaviors and combat problems like obesity.

Games teach us the the key role of engagement--how to keep people involved in tasks to promote individual and social engagement.  If we can learn from how games promote engagement, we may have something very revolutionary.

Chatfield has written a book titled Fun, Inc where he outlines how virtual games can be a good place to learn new approaches in the real world.

I think Chatfield is on to an important issue here.  Why can't we take some of the principles of popular games and apply them to things like learning algebra or organic chemistry?  So far, educational software has not progressed at the speed or complexity of video gaming.  Perhaps by learning how gamers are rewarded and engaged in virtual reality games we can provide more effective online educational software.

Photo of Juno Beach, Florida sun rise with filter from the author's private collection.