جستجو برای حافظه اپیزودیک در حیوانات و کودکان: چشم انداز برای یک مینیمالیسم جدید
|کد مقاله||سال انتشار||مقاله انگلیسی||ترجمه فارسی||تعداد کلمات|
|33631||2009||11 صفحه PDF||سفارش دهید||12720 کلمه|
Publisher : Elsevier - Science Direct (الزویر - ساینس دایرکت)
Journal : Neuropsychologia, Volume 47, Issue 11, September 2009, Pages 2330–2340
Because animals and young children cannot be interrogated about their experiences it is difficult to conduct research into their episodic memories. The approach to this issue adopted by Clayton and Dickinson [Clayton, N. S., & Dickinson, A. (1998). Episodic-like memory during cache recovery by scrub jays. Nature, 395, 272–274] was to take a conceptually minimalist definition of episodic memory, in terms of integrating information about what was done where and when [Tulving, E. (1972). Episodic and semantic memory. In E. Tulving, & W. Donaldson (Eds.), Organisation of memory (pp. 381–403). New York: Academic Press], and to refer to such memories as ‘episodic-like’. Some claim, however, that because animals supposedly lack the conceptual abilities necessary for episodic recall one should properly call these memories ‘semantic’. We address this debate with a novel approach to episodic memory, which is minimalist insofar as it focuses on the non-conceptual content of a re-experienced situation. It rests on Kantian assumptions about the necessary ‘perspectival’ features of any objective experience or re-experience. We show how adopting this perspectival approach can render an episodic interpretation of the animal data more plausible and can also reveal patterns in the mosaic of developmental evidence for episodic memory in humans.
About the most profound result of the conceptual revolution set in train by Endel Tulving’s introduction of the notion of episodic memory (Tulving, 1972) was that it revived the scientific study of experience, as opposed to behaviour and representation. This is because episodic memory is essentially the re-experiencing of a situation. Adult humans can, of course, report on their experiences and can indeed judge whether they simply know something or whether they can recollect experiencing it (Gardner, 1988 and Tulving, 1985). But how should this reintroduction of experience impact upon the scientific study of animals and young children? This is the question we shall tackle in our paper, by examining the implications for a new form of minimalism about episodic memory for comparative and developmental psychology. First, we need to explain what is intended by the term minimalism. The original definition of episodic memory offered by Tulving is an example of conceptual minimalism, in our terms. For, to say that “Episodic memory stores and retrieves information about temporarily-dated episodes or events, and temporal–spatial relations among events (Tulving, 1972, p. 385) and that ‘To ask a person about some item in episodic memory means to ask him when did event E happen, or what events happened at time T′ ( Tulving, 1972, p. 388) would seem to be to omit a lot of what is seemingly essential to human episodic memory in terms of subjective experience and of conceptual abilities. Of course, over the years Tulving, 1983, Tulving, 1985, Tulving, 2000, Tulving, 2002 and Tulving, 2005 has added layers to this minimalism until it contains all one could desire in terms of phenomenal and conceptual richness: ‘[Episodic memory] is probably unique to humans. It makes possible mental time-travel through subjective time—past, present and future. This mental time travel allows the “owner” of the episodic memory (“self”), through the medium of autonoetic awareness, to remember one’s own previous “thought about” experiences…” ( Tulving, 2005, p. 15). Meanwhile, over in developmental psychology, Josef Perner has stressed both the necessary contribution to episodic memory of the theory-like ability to appreciate how past perceptual experiences can cause current knowledge (Perner, 2001) and the role of introspective abilities that are similarly theory-like (Perner, Kloo, & Stöttinger, 2007). This too is a far cry from the minimalism of the early 1970s. What, then, is the empirical cash-value of the early minimalism espoused by Tulving and later denied by theorists such as Tulving and Perner? It is that if an organism, not necessarily a human adult, can recall what happened where, and when (a WWW memory) then it has achieved episodic recall. According to one of us, this implication follows from the kind of 1972 definitions quoted here ( Clayton & Dickinson, 1999); and the legitimacy of this reading has never been challenged by Tulving. Indeed he has acknowledged that “Nicola Clayton’s scrub-jays would have been certified as full-fledged episodic creatures back in 1972” ( Tulving, 2005, p. 47). It goes without saying, that this view of episodic memory does not invite the phrase ‘is probably unique to humans’. Given this background, it is not surprising that there is currently an impasse between those who argue that the existence of WWW memories in animals (in Western Scrub-Jays in particular) means that they possess episodic memories, and those who believe that we should take episodic memory to mean just what Tulving’s later elaborations of it mean (principal members of the latter camp are Suddendorf and Corballis, and Tulving and his collaborators; e.g. Suddendorf and Corballis, 1997 and Suddendorf and Corballis, 2007; Tulving, 2002 and Tulving, 2005). Meanwhile, enthusiasts for the minimalist definition can reply that there is no reason why one may not prefer a psychologist’s earlier phase of theorising to later ones, and that indeed we have witnessed this in Hulme and Mackenzie (1992) on Baddeley’s model of working memory and Pinker and Jackendoff (2005) on Chomsky’s theory of syntax. But the sceptic will reply, in turn, that it is not just a question of early versus late-phase theorising, because there is a very good reason why Tulving made the theoretical elaborations he made, namely, in order to capture these additional features of human episodic memory. It is one thing to use the empirical framework afforded by the 1972 definition to collect evidence for ‘episodic-like’ memory (Clayton & Dickinson, 1998; Clayton, Bussey, & Dickinson, 2003) but quite another to refer to the jays’ performance in terms of ‘mental time travel’. We feel, however, that the enthusiast’s reply is a strong, if not unanswerable, one. Episodic memory involves an organism re-experiencing an earlier situation. Given this, it stands to reason that just as human episodic memory will inherit what is present in human experience, so will avian episodic memory inherit the character of avian experience. It is a datum that human experience takes place within a background of self-awareness and networks of conceptual abilities, while it is our best bet that avian experience does not do so, or at least does so to a lesser extent. Therefore, we should adopt a minimalist non-conceptual account to study avian episodic memory. In itself, however, this answer will not allow an escape from the impasse, mainly because it is so easy to describe WWW memories in semantic terms, that is, in terms of the animal just knowing what was hidden where and when as opposed to re-experiencing the caching event. But we believe the case for a minimalist account of episodic memory has been made, if we are serious about the very possibility of its existing in animals. Our aim, then, is to introduce a new form of minimalism. In later sections we shall describe this and then show how it can be applied to some current developmental data. All we will say about it for now is this: Our form of minimalism claims as a necessary component of episodic memory in all creatures, and perhaps as a sufficient condition for episodic memory in animals, that the organism re-experiences a perceptual relation between itself and data of some kind. We call this a “perspective”; and hence use the term perspectivism. This relation is most naturally understood in the case of spatial coding, but it also exists in terms of temporal relations and can also be easily appreciated with respect to modal relations. We shall elaborate this claim in Section 2. In fact, the following issues will be covered in this paper. 1. A review of the evidence for episodic memory in animals, with particular attention to the WWW experiments. 2. Minimalism explained. We discuss the meaning of “non-conceptual content” in relation to episodic memory, and set out the perspectivism thesis, describing its roots in Kantian theory. 3. The implications of the perspectivism thesis for the development of episodic memory are followed through. The discussion of how episodic cognition can be assessed in children will illustrate the empirical cash-value of the thesis, because in some developmental tasks perspectivism has been assessed and in others it has not. 4. We take stock and also sketch some novel tasks that could be given to children and animals in order to directly assay the perspectival nature of their memory traces.