13.6 Glocal Memory 261

13.6 Glocal Memory 261 Glocal memory overcomes the dichotomy between localized memory (in which each memory item is stored in a single location within an overall memory structure) and distributed memory (in which a memory item is stored as an aspect of a multi-component memory system, in such a way that the same set of multiple components stores a large number of memories). In a glocal memory system, most memory items are stored both locally and globally, with the property that eliciting either one of the two records of an item tends to also elicit the other one. Glocal memory applies to multiple forms of memory; however we will focus largely on percep- tual and declarative memory in our detailed analyses here, so as to conserve space and maintain simplicity of discussion. The central idea of glocal memory is that (perceptual, declarative, episodic, procedural, etc.) items may be stored in memory in the form of paired structures that are called (key, map) pairs. Of course the idea of a “pair” is abstract, and such pairs may manifest themselves quite differently in different sorts of memory systems (e.g. brains versus non-neuromorphic AT systems). The key is a localized version of the item, and records some significant aspects of the items in a simple and crisp way. The map is a dispersed, distributed version of the item, which represents the item as a (to some extent, dynamically shifting) combination of fragments of other items. The map includes the key as a subset; activation of the key generally (but not necessarily always) causes activation of the map; and changes in the memory item will generally involve complexly coordinated changes on the key and map level both. Memory is one area where animal brain architecture differs radically from the von Neu- mann architecture underlying nearly all contemporary general-purpose computers. Von Neu- mann computers separate memory from processing, whereas in the human brain there is no such distinction. In fact, it’s arguable that in most cases the brain contains no memory apart from processing: human memories are generally constructed in the course of remembering [Ros88], which gives human memory a strong capability for “filling in gaps” of remembered experi- ence and knowledge; and also causes problems with inaccurate remembering in many contexts [BF71, RM95] We believe the constructive aspect of memory is largely associated with its glocality. The remainder of this section presents a fuller formalization of the glocal memory concept, which is then taken up further in three later chapters: e Chapter ?? discusses the potential implementation of glocal memory in the human brain e Chapter ?? discusses the implementation of glocal memory in attractor neural net systems e Chapter 23 presents Glocal Economic Attention Networks (ECANs), rough analogues of glocal Hopfield nets that play a central role in CogPrime. Our hypothesis of the potential general importance of glocality as a property of memory systems (beyond just the CogPrime architecture) — remains somewhat speculative. The presence of glocality in human and animal memory is strongly suggested but not firmly demonstrated by available neuroscience data; and the general value of glocality in the context of artificial brains and minds is also not yet demonstrated as the whole field of artificial brain and mind building remains in its infancy. However, the utility of glocal memory for CogPrime is not tied to this more general, speculative theme — glocality may be useful in CogPrime even if we’re wrong that it plays a significant role in the brain and in intelligent systems more broadly. HOUSE_OVERSIGHT_013177