Dissociating Long-term Memory Systems: Comment on Nyberg and Tulving (1996)

Nyberg and Tulving (1996) presented functional, developmental, psychopharmacological and neuropsychological evidence for each possible pairwise dissociation between episodic, semantic, procedural and PRS memory systems and concluded that these systems are therefore independent. I argue that this exercise is questionable on a number of grounds, and consider in detail the evidence that Nyberg and Tulving cite in favour of one particular dissociation, that between episodic and procedural memory. I suggest that a truer interpretation of the evidence is that these types of memory are closely linked, and that the multiple memory systems view fails to account for a variety of findings.