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The Motivation System 113

In living systems, it is believed that these individual facets are organized in a highly
interdependent fashion. Physiological activity is hypothesized to physically prepare the
creature to act in ways motivated by action tendencies. Furthermore, both the physiological
activities and the action tendencies are organized around the adaptive implications of the
appraisals that elicited the emotions. From a functional perspective, Smith (1989) and
Russell (1997) suggest that the individual components of emotive facial expression are also
linked to these emotional facets in a highly systematic fashion.
In the remainder of this chapter, I discuss the relation between the eliciting condition(s),
appraisal, action tendency, behavioral response, and observable expression in Kismet’s
implementation. An overview of the system is shown in figure 8.2. Some of these aspects
are covered in greater depth in other chapters. For instance, detailed presentations of the

Motor Expression Oculo-Motor
Face Posture Voice Neck Eyes
net arousal, net valence,
net stance of active emotion
Motor Skills
emotional emotional
expression response
Emotion System Behavior System
Emotion Arbitration Social Stim
J A F D S E
active
elicitor emotion Seek Engage
contributions
Emotion Elicitors
Engage Seek Avoid
JE AE FE DE SE EE
affectively tagged
contributions (behaviors, Flee Withdraw
motivations,perceptions) success,
frustration
High-Level Perceptual System
Affective Assesment Orient Play
perceptual
Releasers
assessments Somatic Markers
Affective and α β
Behavioral χ
Context α χ β
& Drives
Perceptual ε δ [A, V, S] [A, V, S] [A, V, S]
Features
ε δ under-stimulated,
[A, V, S] [A, V, S] balanced,
overwhelmed
Figure 8.2
An overview of the emotion system. The antecedent conditions come through the high-level perceptual system
where they are assessed with respect to the robot’s “well-being” and active goals. The result is a set of behavior and
emotional response-specific releasers. The emotional response releasers are passed to an affective appraisal phase.
In general, behaviors and drives can also send influences to this affective appraisal phase. All active contributions
are filtered through the emotion elicitors for each emotion process. In the emotion arbitration phase, the emotion
processes compete for activation in a winner-take-all scheme. The winner can evoke its corresponding behavioral
response (such as escape in the case of fear). It also evokes a corresponding facial expression, body posture,
and vocal quality. These multi-modality expressive cues are arbitrated by the motor skill system.