HEAL has a line of research dedicated to understanding the causes, consequences, and manifestations of drug intoxication and withdrawal by using drug administration and deprivation paradigms.

Notable Contributions:

  • Urge to smoke and negative affect are among the most robust tobacco withdrawal symptoms,1 anhedonia appears to be a valid withdrawal symptom,2 and withdrawal – related smoking urge, negative affect, and diminished positive affect mediate the effect abstinence on smoking reinstatement and relapse propensity.3
  • There are three causes of tobacco withdrawal symptoms – pharmacological (nicotine reduction), sensorimotor (loss of the smoking ritual), and expectancy (beliefs about the effects of stopping smoking) effects on tobacco withdrawal – that each of these processes may have different effects on the expression of withdrawal symptoms.4
  • Amphetamine produces robust effects on mood, the drug effect profile of amphetamine varies according to one’s personality and emotional functioning.5
  • The smoking cessation medications of nicotine patch, nicotine lozenge, and bupropion differ in their overall effectiveness,6 and may be more effective for people with certain genes, psychiatric histories, and other charcteristics.7
  • In work lead by collaborators at UCLA, naltrexone may an effective for smoking cessation, methamphetamine addiction, and other problems depending on context.8


This work advances basic knowledge on the neuropharmacological underpinnings of mood, the addictiveness of drugs, and the expression of withdrawal—a core element of addiction. Furthermore, this work furthers the impact of existing medications for addiction and may lead to the development of novel medications.