USF neuroscientist Brendan Walker has found that when kappa opioid receptors in the brain are activated by alcohol-induced “feel bad” peptides called dynorphins, they can stimulate brain dysregulations that lead to maladaptive behaviors—including overconsumption of alcohol and possibly leading to alcohol dependence.

These brain dysregulations include dysphoria associated with negative emotional states like depression and anxiety, as well as impaired motivation, judgment, and decision-making. Walker says these dysregulations can “extend to all drugs of abuse, whether it be opiates like heroin, or psychostimulants like cocaine,” because they cause similar brain changes.

• Brendan Walker