Page 78 - Foundations of Cognitive Psychology : Core Readings

The Appeal of Parallel Distributed Processing 77

Figure 4.10
Characteristics of a number of individuals belonging to two gangs, the Jets and the Sharks.(From
‘‘Retrieving General and Specific Knowledge from Stored Knowledge of Specifics’’ by J.L.Mc-
Clelland, 1981, Proceedings of the Third Annual Conference of the Cognitive Science Society,Berkeley,
CA.Copyright 1981 by J.L.McClelland.Reprinted by permission.)

stance node.A probe which contains misleading features will most strongly
activate the node that it matches best.This will clearly be a poorer cue than one
which contains no misleading information—but it will still be sufficient to
activate the ‘‘right answer’’ more strongly than any other, as long as the intro-
duction of misleading information does not make the probe closer to some
other item.In general, though the degree of activation of a particular instance
node and of the corresponding name nodes varies in this model as a function of
the exact content of the probe, errors in the probe will not be fatal unless they
make the probe point to the wrong memory.This kind of model’s handling of
incomplete or partial probes also requires no special error-recovery scheme to
work—it is a natural by-product of the nature of the retrieval mechanism that it
is capable of graceful degradation.
These aspects of the behavior of the Jets and Sharks model deserve more
detailedconsideration than thepresent spaceallows.. ..We do,however,have