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 Drone vs. truck deliveries: Which create less carbon pollution?
31.05.2017 | University of Washington

nachricht New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

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: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>