Further evidence on the effects of symbolic distance on Stroop-like interference

Pavese and Umilta found that, in an enumeration task, Stroop-like interfere nce is larger when the digit identity is symbolically close to the enumerat ion response than when it is symbolically far. In two experiments testing 4 9 undergraduates, we further explored this phenomenon using Francolini and Egeth's paradigm. We found that symbolic distance affected interference eve n when the stimulus was briefly presented and masked. In Exp. 2, which test ed numerosities outside the subitizing range, individuals used a different enumeration strategy but showed the same symbolic distance effect. These re sults support the hypothesis that Stroop interference found in enumeration tasks depends on a rapid and automatic activation of digits' magnitude repr esentation.