ABSTRACT
Smoking cessation treatment outcomes may be heavily influenced by genetic variations among smokers. Therefore, identifying specific variants that affect response to different pharmacotherapies is of major interest to the field. In the current study, we systematically review all studies published in or after the year 1990 which examined one or more gene-drug interactions for smoking cessation treatment. Out of 644 citations, 46 articles met the inclusion criteria for the systematic review. We summarize evidence on several genetic polymorphisms (CHRNA5-A3-B4, CYP2A6, DBH, CHRNA4, COMT, DRD2, DRD4 and CYP2B6) and their potential moderating pharamacotherarpy effects on patient cessation efficacy rates. These findings are promising and call for further research to demonstrate the effectiveness of genetic testing in personalizing treatment decision-making and improving outcome.
Subject(s)
Pharmacogenetics/trends , Smoking Cessation , Smoking/genetics , Tobacco Use Disorder/genetics , Cytochrome P-450 CYP2A6/genetics , Genetic Variation , Humans , Nerve Tissue Proteins/genetics , Nicotine/genetics , Nicotine/metabolism , Receptors, Nicotinic/genetics , Smoking/physiopathology , Tobacco Use Disorder/epidemiology , Tobacco Use Disorder/pathologyABSTRACT
Stroop interference is attenuated in mostly incongruent lists, as compared with mostly congruent ones. This finding is referred to as the list-wide proportion congruence effect. The traditional interpretation refers to the strategic biasing of attention via list-wide control. In mostly incongruent lists, attention is biased away from the irrelevant words, whereas in mostly congruent lists, words are more fully processed. According to the item-specific account, the list-wide proportion congruence effect reflects stimulus-driven mechanisms, and not list-wide control. The unambiguous evidence available to date strongly favors the item-specific account. Using a picture-word Stroop task, we demonstrate a list-wide proportion congruence effect for 50% congruent items that are embedded in mostly incongruent and mostly congruent lists. This novel finding illustrates that the list-wide proportion congruence effect is not entirely dependent on item-specific contributions and supports the list-wide control account. We discuss factors impacting the emergence of list-wide control in Stroop tasks.
Subject(s)
Attention , Pattern Recognition, Visual , Stroop Test , Adolescent , Female , Humans , Male , Photic Stimulation , Reaction Time , Young AdultABSTRACT
The item-specific proportion congruency (ISPC) effect is the finding of attenuated interference for mostly incongruent as compared to mostly congruent items. A debate in the Stroop literature concerns the mechanisms underlying this effect. Noting a confound between proportion congruency and contingency, Schmidt and Besner (2008) suggested that ISPC effects are entirely contingency based. We introduce a broader theoretical analysis that points to the contribution of both contingency and item-specific control mechanisms. Our analysis highlights that proportion congruency is not confounded with contingency when the relevant dimension functions as the ISPC signal, and predicts that evidence of item-specific control should be obtained by shifting the signal from the irrelevant to the relevant dimension. We examine this prediction in a picture-word Stroop paradigm. When the relevant dimension functions as the ISPC signal (Experiments 1 and 2), evidence of control is obtained. When the irrelevant dimension functions as the ISPC signal (Experiment 3), contingencies can account for the ISPC effect. These patterns support our theoretical analysis, challenge a pure contingency account, and favor the inclusion of control in accounts of ISPC effects.
