Distributed Representation
A distributed representation is a concept that is central to connectionism. In a connectionist network, a distributed representation occurs when some concept or meaning is represented by the network, but that meaning is represented by a pattern of activity across a number of processing units (Hinton et al, 1986). In other words, the meaning is not locally represented by a single unit that is analogous to a "grandmother cell".
One advantage of distributed representations is that they provide damage resistance and graceful degradation (Medler et al., 2005). A disadvantage of such representations is that they make the internal structure of a trained network very difficult to interpret (Dawson, 2004).
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(Added November 2009)