Fear-object perception: does it entail the involuntary capture of attention?

The idea that fearful stimuli are automatically detected i.e. without attention, is challenged by the hypothesis that detection of threatening stimuli is facilitated by the involuntary, stimulus-driven recruitment of attentional resources. In order to clarify this question, we studied spiders detection in arachnophobic individuals by means of an iconic version of the Attentional Blink Task (AB). The experiment consisted of two tasks: 1) Probe detection within a rapid sequence of distractors, including a Critical Distractor (CD); 2) Probe detection and identification of the CD (Target). In this case, the close temporal proximity of CD-Target and Probe typically produces the so-called AB effect, that is the decrease of Probe visibility, due to competition for limited attentional resources. In both tasks, CD-Target was either a spider (50%) or an innocuous animal shape (50%), and Probe (a rabbit icon) was presented at one out of 3 possible lags from the CD-Target. At lag I (100 ms), arachnophobics, at difference with controls, exhibited an AB effect also when the spider was the CD to be ignored. Moreover, Probe detection scores were inversely correlated with spider recalls at lag I. In conclusion, our findings contrast the automatic view of threat detection, and support an attention capturing mechanism automatically driven by the fearful connotation of the stimulus.