section_path: Developmental biological model
section_name: Developmental biological model
paragraph_text: Developmental biological model
  
  Modern conceptions of personality, such as the Temperament and Character Inventory have suggested four basic temperaments that are thought to reflect basic and automatic responses to danger and reward that rely on associative learning. The four temperaments, harm avoidance, reward dependence, novelty-seeking and persistence, are somewhat analogous to ancient conceptions of melancholic, sanguine, choleric, phlegmatic personality types, although the temperaments reflect dimensions rather than distance categories.
  
  The harm avoidance trait has been associated with increased reactivity in insular and amygdala salience networks, as well as reduced 5-HT2 receptor binding peripherally, and reduced GABA concentrations. Novelty seeking has been associated with reduced activity in insular salience networks increased striatal connectivity. Novelty seeking correlates with dopamine synthesis capacity in the striatum and reduced auto receptor availability in the midbrain. Reward dependence has been linked with the oxytocin system, with increased concentration of plasma oxytocin being observed, as well as increased volume in oxytocin-related regions of the hypothalamus. Persistence has been associated with increased striatal- mPFC connectivity, increased activation of ventral striatal-orbitofrontal-anterior cingulate circuits, as well as increased salivary amylase levels indicative of increased noradrenergic tone.