ABSTRACT
INTRODUCTION: The majority of smokers begin consumption in adolescence and the earlier initiation of cigarette smoking is associated with a greater likelihood of cigarette dependence. Graphic health warnings (GHW) are one of the most used strategies to communicate the consequences of cigarette smoking, but little is known about their ability to increase inhibitory control and thus prevent consumption. The objective of the present study was to evaluate the effects of different sizes of GHWs on inhibitory control in adolescents. We hypothesized that GHWs promote inhibitory control, and increasing GHW size, enhance inhibitory control. METHODS: Fifty-nine participants completed a Go/No-Go task during electroencephalographic recording. The No-Go stimuli were pictures of cigarette packs without GHWs, and cigarette packs with GHWs that covered 30% or 60% of the front (main side) of the pack. The event-related potential N200 component and behavioral measures in the Go/No-Go task were analyzed. RESULTS: Separate mixed-model analysis of variance (ANOVAs) were used for N200 component (amplitude and latency) and behavioral data. The GHWs increased the amplitude of the N200 potential, especially GHWs that covered 60% of the front of the pack. The behavioral data showed that GHWs that covered 60% of the front of the pack generated higher a percentage of accuracy in No-Go trials (ie, fewer commission errors). CONCLUSIONS: These results suggest that GHWs increase inhibitory control in adolescents, especially when the GHWs cover 60% of the front of the cigarette pack. IMPLICATIONS: GHWs with an increased size (60% of the front of the cigarette pack vs. 30%, the minimum size, proposed by the World Health Organization) recruit additional cognitive resources and thus can effectively increase inhibitory control both in adolescent smokers and nonsmokers. Accordingly, the use of larger GHW has the potential of becoming an effective public policy strategy to inhibit smoking in adolescents.