Search and decision processes in semantic memory

The present study investigated the role of semantic variables, derivable from multidimensional scaling, in search and decision processes. In Experiment I, both the number of categories defining the memory set and the semantic distance separating the categories were shown to influence latency decisions for two types of tasks differing in task specificity: a Defined condition, in which the category names and positive members were specified, and an Undefined condition, in which only the category names were provided. In Experiment II, the importance of semantic distance on negative decisions was shown for both tasks. Evidence that maximal semantic separation among categories in the memory set may result in a self-terminating search was found for both the Defined and Undefined conditions. It was concluded that a Sternberg scan for presence-absence and a category verification task involving category membership may be similarly affected by semantic variables.