The dopaminergic system

Background: Many addictive substances can lead to changes in dopamine levels in the brain. For example, both cocaine and alcohol are associated with elevated levels of baseline striatal dopamine. Although other neurotransmitter systems have been implicated, there is strong evidence that substance addiction primarily involves the dopamine (dopaminergic) system. The dopaminergic system also seems to play a key role in behavioural addictions, especially pathological gambling

Suggested Readings: van Holst et al. (2018), DSM-V (2013) criteria for Pathological Gambling, Nutt et al. (2015)

Question : What do the findings of van Holst et al. (2018) tell us about dopamine in the brains of pathological gamblers?