TY - JOUR PY - 1993// TI - What enumeration studies can show us about spatial attention: evidence for limited capacity preattentive processing JO - Journal of experimental psychology: human perception and performance A1 - Trick, Lana M. A1 - Pylyshyn, Z. W. SP - 331 EP - 351 VL - 19 IS - 2 N2 - Subitizing, the enumeration of 1-4 items, is rapid (40-120 ms/item) and accurate. Counting, the enumeration of 5 items or more, is slow (250-350 ms/item) and error-prone. Why are small numbers of items enumerated differently from large numbers of items? It is suggested that subitizing relies on a preattentive mechanism. Ss could subitize heterogeneously sized multicontour items but not concentric multicontour items, which require attentional processing because preattentive gestalt processes misgroup contours from different items to form units. Similarly, Ss could subitize target items among distractors but only if the targets and distractors differed by a feature, a property derived through preattentive analysis. Thus, subitizing must rely on a mechanism that can handle a few items at once, which operates before attention but after preattentive operations of feature detection and grouping.
Language: en
LA - en SN - 0096-1523 UR - http://dx.doi.org/ ID - ref1 ER -