Yes, there is a preferential detection of negative stimuli. A response to Labiouse.

Abstract

In a previous issue of Psychological Science, we (Dijksterhuis & Aarts,2003) reported evidence supporting the hypothesis that less stimulusinput is needed to detect negative stimuli than to detect positivestimuli. Commenting on that research, Labiouse (2004) stated that it‘‘suffers from a number of limitations, methodological flaws, andtheoretical ambiguities’’ (p. 364). Because he did not elaborate on thesupposed theoretical ambiguities, we focus on methodological aspectsof our work in this reply. We show that a significant part of Labiouse’scriticism stems from a misreading of our report. As for the more well-founded side of his critique, which concerns the limitations of onedesign we used, we qualify his conclusions and discuss supportiveevidence recently obtained from a more appropriate paradigm.Labiouse reviewed our experiments separately. In Experiment 1,participants were briefly presented with masked stimuli consisting of25% positive words, 25% negative words, and 50% nonwords. Oneach trial, participants had to indicate whether the stimulus was aword or not. As hypothesized, participants reported having seen aword more often when presented with a negative word (54.5%) thanwhen presented with a positive word (40.1%) or a nonword (33.5%).Labiouse concluded that it is possible that participants respondedrandomly to the trials. Unfortunately, this conclusion builds on amisreading of our article. Labiouse inferred that the mean ‘‘word’’response rate was 60% across conditions, which would indeed havebeen problematic. However, this percentage was not 60 but 40.4, ascan be easily derived from the percentages listed in the previousparagraph. Thus, Labiouse’s criticism appears to be entirely un-founded: Participants were significantly better at detecting negativethan positive information (i.e., 54.5% vs. 40.1%), and their detectionof negative information (i.e., 54.5%) was better than what would beexpected from the average ‘‘word’’ response rate (i.e., 40.4%).Labiouse criticized Experiments 2 and 3 on different grounds. Inthese experiments, participants were presented with words only; 50%of the words were positive and 50% were negative. Participants’ taskwas to indicate whether each stimulus was a positive or negative word.In both Experiments 2 and 3, the number of correctly categorizednegative words was significantly higher than the number of correctlycategorized positive words. In addition, the correct categorization ofnegative words differed significantly from chance, whereas correctcategorization of positive words did not. Admittedly, however, inter-pretation of these data remains problematic, as this design does notallow one to assess detection of negative and positive words inde-pendently of response bias.Being unable to assess detection independently of response bias isan issue, however, only when the direction of this bias is such that itoffers an explanation that is an alternative to the authors’ conclusions.In order to prevent throwing out the baby with the bathwater, a closerlook at the data of Experiments 2 and 3 is warranted. In Experiment 2,participants categorized as negative 56.3% of the negative words and52.0% of the positive words. Because responses to both negative andpositive words contributed to a response bias toward ‘‘negative’’ re-sponses, Labiouse was right to conclude that this data set does notallow useful conclusions.For Experiment 3, however, the situation is quite different. In thiscase, participants categorized as negative 57.7% of the negative wordsand 48.7% of the positive words. That means that in this experimentthe reponse bias toward negative responses was caused solelyby...indeed, the negative words. Now is this really a response bias?Labiouse did not discuss Experiment 3 explicitly in his note, whereaswe feel this experiment shows that we should indeed be careful withthe bathwater. We would like to keep the baby, if possible.But let us go one step further. Despite the support for our hypothesisthat we have just discussed, the paradigm used in Experiments 2 and3 did not allow an independent comparison of participants’ sensitivityto positive and negative information. This comparison can be made inthe context of an experiment involving four tasks: affective decisionson positive words (i.e., deciding whether positive and neutral wordsare positive or neutral), lexical decision on positive words (i.e., de-ciding whether positive words and nonwords are words or nonwords),affective decisions on negative words (i.e., deciding whether negativeand neutral words are negative or neutral), and lexical decision onnegative words (i.e., deciding whether negative words and nonwordsare words or nonwords).We recently conducted such a study (Corneille, Vermeulen, Lumi-net, & Dijksterhuis, 2003). We relied on a signal detection analysis to