The Effect of Long-Term Memory Knowledge on Rehearsal and Refreshing in Working Memory

It was suggested that the impact of long-term knowledge on short-term memory (STM) could either be at encoding and maintenance or at recall (Thorn, Frankish, & Gathercole, 2009). In two experiments, we manipulated the characteristics of long-term knowledge through word-frequency or lexicality. We also varied the implication of the mechanisms of maintenance, refreshing or rehearsal. First, the effect of long-term knowledge on refreshing was investigated manipulating frequency of words to remember and attentional load of the concurrent processing. No interaction between word frequency and cognitive load was found. A second experiment investigated the effect of long-term knowledge on both rehearsal and refreshing mechanisms. Words and non-words to remember were used while articulatory suppression and cognitive load were orthogonally manipulated. Neither articulatory suppression nor cognitive load interplayed with lexicality. These findings favour the view that long-term knowledge affects STM at recall, for example through redintegration process (Hulme et al., 1997).