T η
Aimpi inothercases
+ Mccf if Fafcf afτd Aimpf > О
(2)
Another internal behaviour required by this layer is external behaviour selector. The role
of external behaviour selector is to decide which external behaviour will be executed in the
current moment, a process which occurs by taking into account the signals recorded at the
Perceptual Persistents level, through a competition process.
A diagram of our BPS at the stage of the modelling of reactive behaviours can be
appreciated in Figure 8. As it can be seen, at this stage of the modelling, two types of external
behaviours can be produced by BeCA: reflex responses, modelled as direct pathways between
the External Perceptions and the Actions levels; and reactive behaviours, mediated by the
internal behaviours perceptual persistence and external behaviour selector and involving a simple
type of action selection.
If no external signals have been perceived, the motor system will execute a default
behaviour (e.g. stand by or wander).
Figure 8. BeCA at the stage of the modelling of reactive behaviours.
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