Basic task included visual search for two complex stimuli (pseudowords). Visual similarity of each item to the target was manipulated. Both Mean and Survivor interaction contrast indicated overall overadditivity in processing. Typical signatures of standard serial and parallel processing were not observed.
Also additional experiments indicated that additivity and consequentially seriality could be observed when either mutual visual similarity of the search items is reduced or when processing is forced to be serial by sequential presentations of the search set.
Several models were tested that includes possible dependency between processes, different mixtures of serial and parallel and model with interaction between items in the search set.
Both Serial and Parallel processing models exhibit similar predicative behavior under specific set of assumptions and fit the data well.
Memory Search (James Townsend, Mario Fific, Leslie Blaha)
Methodology involving factorial variation in order to determine mental architecture and to assess processing capacity has been greatly expanded over the past several decades. However, it has never been adapted to study the realm where much of the interest began in the 1960s: short-term memory search. We present a new method of manipulating probe-to-memory item processing speed and our initial results for loads n=2,4. Three variables were manipulated in this experiment: number of processing elements (2), phonemic dissimilarity of a target to the particular memorized element (high, low) and duration between memorized set and a target (short-long). We employ the recent results involving the distribution functions rather than means alone. Our results suggest that some observers really are serial whereas others are strongly parallel. Thus, these fine grained analyses portend quite striking individual differences in this basic cognitive task.
