During acute intoxication:

• Mesolimbic pathway becomes activated and dopamine is upregulated
• This leads to positive reinforcing symptoms like euphoria
• Other neurotransmitter systems in positive reinforcement include endogenous opioids, γ-aminobutyric acid, glutamate, neuropeptide Y, and glucocorticoids
• The frontal cortex function is important in the effects of craving and inhibitory behavioral control