Based on evidence from physiopsychological and animal studies, variation in the temperament dimensions is thought to be influenced by activity in specific neurotransmitter pathways (Cloninger, 1986, 1987) – Novelty Seeking by dopaminergic activity, Harm Avoidance by serotonergic activity, and Reward Dependence by noradrenergic activity. Gerra et al. (2000) found that individual’s hormonal response to specific neurotransmitter agonists correlated with TPQ scale scores in accordance with Cloninger’s theory, but further evidence is needed to support the relationship between the different neurotransmitter pathways and Cloninger’s temperament scales.
