The role of working memory in problem solving

The combination of moment-to-moment awareness and instant retrieval of archived information constitutes what is called the working memory, perhaps the most significant achievement of human mental evolution. (Goldman-Rakic, 1992, p. 111) Working memory plays an essential role in complex cognition. Everyday cognitive tasks – such as reading a newspaper article, calculating the appropriate amount to tip in a restaurant, mentally rearranging furniture in one's living room to create space for a new sofa, and comparing and contrasting various attributes of different apartments to decide which to rent – often involve multiple steps with intermediate results that need to be kept in mind temporarily to accomplish the task at hand successfully. (Shah & Miyake, 1999, p. 1) More than 25 years ago, Baddeley and Hitch (1974) lamented, “Despite more than a decade of intensive research on the topic of short-term memory (STM), we still know virtually nothing about its role in normal information processing” (p. 47). The primary concern for Baddeley and Hitch was the presumed centrality of limited-capacity short-term memory in contemporary models of memory, including Atkinson and Shiffrin's (1968) “modal model.” For example, Baddeley and Hitch described a patient with brain-damage (K.F.) who exhibited grossly deficient performance on tests of short-term memory but normal performance on long-term learning tasks. Logically, this could not occur if information passes from short-term memory to long-term memory.