Psychology Memory Formation
Key words: Episodic Memory; Hippocampus; Binding; Recruitment
Abstract
The memorization of events and situations (episodic memory) requires the rapid formation of a memory trace consisting of several functional components. A computational model is described that demonstrates how a transient pattern of activity representing an episode can lead to the rapid recruitment of appropriate circuits as a result of long-term potentiation within structures whose architecture and circuitry match those of the hippocampal formation, a neural structure known to play a critical role in the formation of such memories.
1 Introduction
We remember our experiences in terms of events and situations that record who did what to whom where and when, or describe states of affairs wherein multiple entities occur in particular configurations. This form of memory is referred to as episodic memory [23] and it is known that the hippocampal system (HS) serves a critical role in the formation of such memories [10, 21, 4, 22].
A number of researchers have proposed models to explain how the HS subserves the episodic memory function.
These include macroscopic system-level models that attempt to describe the functional role of the HS as well as more detailed computational models that attempt to explicate how the HS might realize its putative function (e.g.,
[11, 14, 22, 8, 13, 12]. While our understanding of the HS and its potential role in memory formation and retrieval has been enhanced by this extensive body of work, several key representational problems associated with the encoding of episodic memories have remained unresolved. In particular, most existing computational models view an item in episodic memory as a feature vector or as a conjunction of features. But for reasons summarized below, such a view of episodic memory is inadequate for encoding events and situations (also see [16, 18]).
First, events are relational objects, and hence, cannot be encoded as a conjunction of
Abstract
The memorization of events and situations (episodic memory) requires the rapid formation of a memory trace consisting of several functional components. A computational model is described that demonstrates how a transient pattern of activity representing an episode can lead to the rapid recruitment of appropriate circuits as a result of long-term potentiation within structures whose architecture and circuitry match those of the hippocampal formation, a neural structure known to play a critical role in the formation of such memories.
1 Introduction
We remember our experiences in terms of events and situations that record who did what to whom where and when, or describe states of affairs wherein multiple entities occur in particular configurations. This form of memory is referred to as episodic memory [23] and it is known that the hippocampal system (HS) serves a critical role in the formation of such memories [10, 21, 4, 22].
A number of researchers have proposed models to explain how the HS subserves the episodic memory function.
These include macroscopic system-level models that attempt to describe the functional role of the HS as well as more detailed computational models that attempt to explicate how the HS might realize its putative function (e.g.,
[11, 14, 22, 8, 13, 12]. While our understanding of the HS and its potential role in memory formation and retrieval has been enhanced by this extensive body of work, several key representational problems associated with the encoding of episodic memories have remained unresolved. In particular, most existing computational models view an item in episodic memory as a feature vector or as a conjunction of features. But for reasons summarized below, such a view of episodic memory is inadequate for encoding events and situations (also see [16, 18]).
First, events are relational objects, and hence, cannot be encoded as a conjunction of
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