Sometimes a separate vector of outputs
and/or phase angles
A matrix of weights (dimensions n X n)
A task
A set of input vectors
(Sometimes) a set of target vectors
An activation rule
A weight rule
A connectionist unit
Why connectionism?
Connectionist models implement parallel constraint satisfaction in
a straightforward way.
This permits processing as the interaction of diverse knowledge sources.
Connectionist networks are good at solving best-match problems.
When a familiar pattern enters the memory system, the
response is a stronger version of the input (recognition).
When an unfamiliar pattern enters the memory system, it is
dampened (unfamiliarity).
When part of a familiar pattern enters the memory system,
the system fills in the missing parts (recall, content-addressable
memory).
When a pattern similar to a stored pattern enters the memory
system,
the response is a version of the input distorted toward the stored
pattern (assimilation).
When a number of similar patterns have been stored, the system
will respond to the central tendency of the stored patterns, even if
the central tendency itself never appeared (prototype effects).
Connectionist networks are robust.
They are resistant to noise.
They gracefully degrade when they are damaged.
They gracefully degrade when they are overloaded with information.
Connectionist networks are based loosely on brains.
Control is distributed.
Computation is handled by massively connected, simple processors
which repeatedly update on the basis of weighted inputs.
Learning consists in enhancing or inhibiting on the basis of local
information the degree to which signals are transmitted between processors.
Memories are distributed.
(Distributed) connectionist representations are flexible.
They are graded.
They are context-dependent.
Connectionist models offer the possibility of grounding
internal representations in perception, action, and affect.
Low-level representations are continuous.
High-level representations can be categorical.
Similarity between patterns is represented directly, and there is
automatic generalization to similar inputs.
There is a wide range of relatively simple, local connectionist
learning algorithms.