Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Toddlers' aggression is strongly associated with genetic factors

21.01.2014
New study provides greater understanding of how to address childhood aggression

The development of physical aggression in toddlers is strongly associated genetic factors and to a lesser degree with the environment, according to a new study led by Eric Lacourse of the University of Montreal and its affiliated CHU Sainte-Justine Hospital. Lacourse's worked with the parents of identical and non-identical twins to evaluate and compare their behaviour, environment and genetics.

"The gene-environment analyses revealed that early genetic factors were pervasive in accounting for developmental trends, explaining most of the stability and change in physical aggression, " Lacourse said. "However, it should be emphasized that these genetic associations do not imply that the early trajectories of physical aggression are set and unchangeable. Genetic factors can always interact with other factors from the environment in the causal chain explaining any behaviour."

Over the past 25 years, research on early development of physical aggression has been highly influenced by social learning theories that suggest the onset and development of physical aggression is mainly determined by accumulated exposure to aggressive role models in the social environment and the media. However, the results of studies on early childhood physical aggression indicate that physical aggression starts during infancy and peaks between the ages of 2 and 4. Although for most children the use of physical aggression initiated by the University of Montreal team peaks during early childhood, these studies also show that there are substantial differences in both frequency at onset and rate of change of physical aggression due to the interplay of genetic and environmental factors over time. Genetically informed studies of disruptive behavior and different forms of aggression across the lifespan generally conclude that genetic factors account for approximately 50% of the variance in the population.

Lacourse and his colleagues posited and tested three general patterns regarding the developmental roles of genetic and environmental factors in physical aggression. First, the most consensual and general point of view is that both sources of influence are ubiquitous and involved in the stability of physical aggression. Second, a "genetic set point" model suggests a single set of genetic factors could account for the level of physical aggression across time. A third pattern labeled 'genetic maturation' postulates new sources of genetic and environmental influences with age. "According to the genetic maturation hypothesis, new environmental contributions to physical aggression could be of short duration in contrast to genetic factors," Lacourse explained.

About the twins cohort

This twin study was initiated by Michel Boivin of Laval University and Richard Tremblay, who is also affiliated with the University of Montreal and University College Dublin. All parents of twins born between April 1995 and December 1998 in the Greater Montreal area (Canada) were invited to participate, which resulted in the participation of 667 monozygotic and dizygotic twin pairs. Monozygotic means the twins originated from the same embryo – they are genetically identical. Dizogytic means they developed in separate embryos, meaning they are not identical.

Mothers were ask to rate their twins physical aggression, by reporting behaviour such as hitting, biting, kicking and fighting, at the ages of 20, 32 and 50 months. "The results of the gene-environment analyses provided some support for the genetic set-point hypotheses, but mostly for the genetic maturation hypotheses," Lacourse said. "Genetic factors always explained a substantial part of individual differences in physical aggression. More generally, the limited role of shared environmental factors in physical aggression clashes with the results of studies of singletons in which many family or parent level factors were found to predict developmental trajectories of physical aggression during preschool." Our results suggest that the effect of those factors may not be as direct as was previously though.

Long-term studies of physical aggression clearly show that most children, adolescent and adults eventually learn to use alternatives to physical aggression. "Because early childhood propensities may evoke negative responses from parents and peers, and consequently create contexts where the use of physical aggression is maintained and reinforced, early physical aggression needs to be dealt with care," Lacourse said. "These cycles of aggression between children and siblings or parents, as well as between children and their peers, could support the development of chronic physical aggression." We are presently exploring the impact of these gene and social environment interactions.

###

About this study

Eric Lacourse, PhD, Michel Boivin, PhD, Mara Brendgen, PhD, Amélie Petitclerc, PhD, Alain Girard, MSc, Frank Vitaro, PhD, Stéphane Paquin, PhD candidate, Isabelle Ouellet-Morin, PhD, Ginette Dionne, PhD and Richard E. Tremblay, PhD published "A longitudinal twin study of physical aggression during early childhood: Evidence for a developmentally dynamic genome" in Psychological Medicine on January 21, 2014.

This research was supported by grants from the National Health Research Development Program, the Social Sciences and Humanities Research Council of Canada, the Quebec Ministry of Health and Social Services, the Canadian Institutes of Health Research, the Canada Research Chair program, the Fonds Québécois de la Recherche sur la Société et la Culture, and the Fonds de la Recherche en Santé du Québec.

E. Lacourse, M. Boivin, M. Brendgen, A. Girard, F. Vitaro, S. Paquin, I. Ouellet-Morin, G. Dionne, and R. E. Tremblay, are affiliated with Research Unit on Children's Psychosocial Adjustment, Ste-Justine Hospital Research Center, affiliated with the University of Montreal. E. Lacourse and S. Paquin are affiliated with the University of Montreal's Department of Sociology, F. Vitaro with its Department of Psychoeducation, and I. Ouellet-Morin with its School of Criminology and the university's affiliated Mental Health Institute of Montreal Research Center. A. Petitclerc is affiliated with the National Center for Children and Families, Teachers College at Columbia University. M. Boivin and G. Dionne are affiliated with the School of Psychology at Laval University. M. Brendgen is affiliated with the Department of Psychology at Université du Québec. R. E. Tremblay is also affiliated with the University of Montreal's departments of psychology and pediatrics and with the School of Public Health, Physiotherapy and Population Science at University College Dublin, Ireland. The University of Montreal is officially known as Université de Montréal.

Julie Gazaille | EurekAlert!
Further information:
http://www.umontreal.ca

More articles from Studies and Analyses:

nachricht Win-win strategies for climate and food security
02.10.2017 | International Institute for Applied Systems Analysis (IIASA)

nachricht The personality factor: How to foster the sharing of research data
06.09.2017 | ZBW – Leibniz-Informationszentrum Wirtschaft

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>