source, food source, etc.), and (2) a signal (representing an internal need) associated with the
unconditioned stimulus from the Drive level of the motivational node was projected to the
Consummatory Preferents level of the cognitive node. These modifications of the coupling
strengths can be seen as learning processes, and they are similar to the adjustment of the
connection weights in an artificial neural network.
The classical conditioning in BeCA is expressed in terms of three types of learning,
which are referred to as: (1) learning of the motor action pattern, consisting in the modification
of coupling strengths of the external behaviour selector elementary behaviours, (2) learning of
the biological meaning, which consists in the modification of the coupling strengths of the
intero/extero/drive congruence elementary behaviours, and (3) learning at a motivational level,
which consists in the modification of coupling strengths of the attention to preferences
elementary behaviours. The rule for the modification of the coupling strengths used by the
three types of learning is given by expression (10).
¾∣7 + 1) =
'(1- ∕5⅛f w+ (z(oj"(i))∕(cr w)) .1 iff (V? (г))
>0
mother case
(10)
where: Fa is the modifiable coupling strength of the elementary behaviour i with respect to the
signal j; O in is the value associated to the condition signal j; O out is the value associated to the
action signal i; $ is a parameter that determines the proportion taken from the coupling
strength corresponding to the previous instant, (0 # $ # 1); 8 is a factor regulating the speed
of the conditioning; and : determines the speed of the extinction of conditioning (0 # : # 1).
The first part of expression (10) regulates the conditioning, whereas the second part regulates
the extinction of the conditioning. For values of $ equal to :, the two parts of this equation
could be reduced to the first.
The coupling strengths will be modified when O out is greater than zero. If Ojin is also
greater than zero, the coupling strength will be increased, while if O in is equal to zero, the
coupling strength will be decreased.
As it can be seen in Figure 10 and Figure 11, each of these learning processes is able to
form or reinforce a segment in the corresponding behavioural column to a neutral stimulus.
Figure 10 shows the crossed trajectory segments by neutral stimuli (grey solid circles) and
unconditioned stimuli (black solid circles) before classical conditioning. Figure 11 shows the
crossed trajectory segments by the neutral stimulus (now, a conditioned stimulus) when the
three types of learning have occurred.
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