CA critical review of
‘An exploration of the serotonin system in antisocial boys with high levels of callous-unemotional traits’ by
C. Moul, C. Dobson-Stone, J. Brennan, D. Howes and M. Dadds (2013)
Aggressiveness is a complicated study due to the fact that it does not act as an integral trait, and increased interest towards the matter of anti-social behaviour is partly explained by the apparent escalation of aggression in contemporary society (Popova, 2006). The human expression of anger is due to a combination of endocrine, neural and behavioural mechanisms and as such, a central question of human history. Children with aggressive behaviour form a heterogeneous ...view middle of the document...
One of these factors is the neurotransmitter serotonin or variations of the serotonin transporter gene (5HTT). In a study by Beitchman, Zai, Muir, Berall, Nowrouzi, Choi and Kennedy (2012) results suggested that there is a significant relationship between oxytocin polymorphism and CU traits in highly aggressive children, with stronger findings among boys. It has also been suggested that genetic changes in particularly sensitive developmental periods and in combination with environmental factors (e.g. parenting styles, socioeconomic status, hormones, puberty) are more likely to produce high Callous-Unemotional (CU) traits in young children (Frick & Viding, 2009). Similarly, in their study Baker, Bezdjian and Raine (2006) conclude that although heritability of antisocial traits makes a strong case, environment plays a crucial role in displaying and magnifying those genetic influences in deviant behaviour. In a study by Viding, Larsson and Jones (2008) it has been reported that high CU traits children exhibit strong genetic effects (heritability of 0.81), but are not affected by environmental factors; whereas those with low CU traits showed moderate genetic dominance (heritability of 0.30) and apparent environmental effects.
In review of Moul, Dobson-Stone, Brennan, Hawes and Dadds’s (2013) evidence of the association between serotonin system and levels of callous-unemotional (CU) traits in anti-social boys the present paper acknowledges its significance of findings. Nevertheless, considering the biological factors underpinning CU traits in young anti-social children should involve other biological risk factors, for example, the role of hormones, neurotransmitters, frontal lobe function etc. Assessing the true origin of anti-social behaviour it is probably worth considering that genetic factors could be moderated by environmental variables, such as the distinct layers of the ecological micro and macro system of the child’s development (Bronfenbrenner, 1979). It is an overall satisfactory constructed study and a well operationalised experiment consistent of good methodology and systematic significant findings, which highlights a possible association between the serotonin system levels in antisocial young male population and levels of CU traits. Sample size; gender specific behavioural patterns; participants’ ethnicity limitations and the wide age range are the main weaknesses of the present study under review.
The authors of the study hypothesised that boys with antisocial behaviour problems and high levels of CU traits would have lower levels of serum serotonin than boys with antisocial behaviour problems and low levels of CU traits. In order to test their hypothesis they have employed 157 boys (3-16 years for the genetic sample and 4-12 years for the serum sample). The sample sizes used for the main measures were split in three separate groups: serotonin system single nucleotide polymorphisms (SNP’s) – Caucasian only...