The name is absent

Then, we will add a layer to our BPS for reactive behaviours. Next, we will add another layer
dealing with the problem of motivated behaviours. Finally, we will refine these layers,
incorporating learning schemes to obtain a higher adaptiveness in the behaviour production.
We will illustrate each layer and refinement process with experiments using our Behaviours
Virtual Laboratory in Chapter 6.

3.5. Modelling Reflex Behaviours

Reflex is one of the simplest forms of behaviour exhibited in animals. In this type of
behaviour a fast action is triggered when a particular external stimulus is perceived. The key
characteristic of a reflex is that the intensity and duration of the triggered action completely
depend on the intensity and duration of the stimulus. There is a rigid relationship between the
stimuli and the action executed (Manning, 1979; McFarland, 1981; Anderson and Donath,
1990). Duration and intensity of reflex behaviours might depend on internal states, but for one
type of stimuli, the triggered action will be of a specified type. This means that in reflex
behaviours there is no action selection problem, because for every stimulus perceived, the
corresponding behaviour will always be executed.

In BeCA we will model reflex behaviours in the following way: for every signal received
from the perceptual system, a corresponding signal will be sent to the motor system.

In the initial approach of our BPS, the reflex behaviours are modelled as a first layer,
which includes the definition of the following components: the External Perceptions, Actions,
and Internal Perceptions blackboard levels, the reflex actions internal behaviour, and the
interface mechanisms exteroceptors, interoceptors, and actuators. These last elements will allow
us to establish connections between the perceptual and motor systems.

From this first layer, we will assume the existence of an internal medium (needs/goals),
although it does not play a role in the control of reflex and reactive behaviours. This is the
reason why the connections between the nodes will appear only at the third layer, for the
modelling of motivated behaviours.

At the External Perceptions level the signals from the external medium are projected,
first sensed and processed by a perceptual system. At the Actions level signals that indicate
which external behaviour must be executed are created. When a signal is created at this level,
the external behaviour associated with this element will be invoked, and the action will be
executed by a motor system. At the Internal Perceptions level signals from the internal medium
are projected, which are sensed by the interoceptors mechanisms.

The exteroceptors mechanisms establish the interface between the perceptual system and
BeCA. Once they receive signals from the perceptual system, they process them (multiplying
them by a specific coupling strength) and register the resulting signals in the External
Perceptions level. In a similar way the interoceptors establish the interface between the internal
medium and BeCA, registering signals in the Internal Perceptions level.

The role of the reflex actions internal behaviour is to allow the immediate activation of
the behavioural columns representing reflex actions, which do not require an internal input for
the execution of the external action associated with this column. The winners of a competition

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