Compact notation for the ordered 'and'
When we consider the internal structure of |
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using 'wait' elements In producing this sequence (B C), it won't
work for C to come out at the same time as B
the delay on C needs to be long enough
for B to be produced. And in the upward direction, the activation
from B has to wait for the activation for C to arrive, since B will get
there first.
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The Wait Element
Now we must consider exactly what the wait element consists of. It must be able to do two important things:
1) it must keep the activation alive during the period of delay, and
2) it must "know" how long to wait.Pathways of the Brain (pg. 99-102) discusses two means of fullfilling these requirements:
Fixed Interval Timing and Feedback Timing.
for the ordered 'and' (downward direction)
Click here to see an animation of how feedback timing works |
for the ordered 'and' (downward direction)
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For the upward direction, or recognition, the mechanism required is slighly different. It is only necessary to keep alive the activation from the first element until the activation from the second arrives. If no further input is received (i.e. at the end of a sentence or phrase when there is no second element) a centrally located reset turns off the activation kept alive in the loop. |
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