Effect of tryptophan depletion on the attentional salience of smoking cues

Psychopharmacology (Berl). 2007 Jun;192(3):317-24. doi: 10.1007/s00213-007-0722-2. Epub 2007 Feb 14.

Abstract

Rationale: There is increasing evidence linking cigarette craving and smoking behavior to serotonergic neurotransmission.

Objectives: The purpose of the current study was to examine the effects of a serotonergic challenge on the attentional salience of various cues associated with cigarettes. We hypothesized that cigarette-related word cues would be more distracting after acute tryptophan depletion than after a placebo challenge. We also hypothesized that smokers vulnerable to recurrent depression would show greater attentional bias towards these cues than smokers without a history of depression.

Methods: Thirty-four smokers diagnosed as having (n = 15) or lacking (n = 19) a history of DSM-IV major depressive disorder (MDD) underwent acute tryptophan depletion (ATD) and placebo challenges in double-blind and counterbalanced order 1 week apart. Five hours after consumption of each mixture, subjects completed a modified Stroop task to measure attentional bias to smoking-related, positive affect, and negative affect word cues. Stroop interference was calculated as a difference score between latencies for the motivationally salient and the neutral (furniture) word lists.

Results: Controlling for change in dysphoric mood from baseline to 5 h, repeated measures MANOVAs showed that ATD, as compared to placebo challenge, produced greater interference for smoking word cues [F(1,29)=4.15, p = 0.05], but not for negative [F(1,29)=2.78, p = 0.11] or positive [F(1,29)=1.60, p = 0.22] affect word cues.

Conclusions: Acutely compromising central serotonergic neurotransmission via ATD heightens the attentional salience of cigarette-related cues, perhaps by triggering reward and motivational deficits underlying nicotine dependence.

Publication types

  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adult
  • Affect
  • Amino Acids / deficiency*
  • Amino Acids / metabolism
  • Attention*
  • Cues
  • Depressive Disorder, Major / psychology
  • Double-Blind Method
  • Female
  • Humans
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Serotonin / metabolism*
  • Smoking / psychology*
  • Smoking Cessation / psychology
  • Tobacco Use Disorder / physiopathology
  • Tobacco Use Disorder / psychology
  • Tryptophan / metabolism*

Substances

  • Amino Acids
  • Serotonin
  • Tryptophan