Immediate memory span for two-dimensional spatial arrays: Effects of pattern symmetry and goodness - Howe, E.; Jung, K. (Elsevier)
Two hundred dot patterns set in a 5 x 5 matrix were constructed with array sizes from 1 to 11 and five amounts of whole and part symmetry. In experiment 1 judged pattern goodness was shown to be a highly reliable increasing function of array size and amount of symmetry, the two effects being independent. In experiment 2 subjects attempted graphic reproduction of each pattern following a 1-sec exposure. Within array sizes the probability of correct pattern reproduction was a robust positive function of amount of symmetry and judged goodness, and this finding confirms the pattern goodness effect on a very general basis. Values of the immediate memory span (size of array for which the probability of correct recall was 0.5) were interpolated from fitted quadratic curves. The resulting values of immediate memory span increased dramatically with amount of symmetry, and ranged from 4.0 for quasi-random patterns to 10.8 for wholly symmetrical ones. Two points were argued in the Discussion. First, that the capacity of primary memory is about three spatial locations, and that such capacity is very effectively increased by retrieval of visual and verbal information from secondary memory. Second, that the differential recall effects originate during encoding rather than as a result of either short-term forgetting or response bias.
http://dx.doi.org/10.1016/0001-6918(86)90020-X
Keywords: CL-CZ