Who Needs Emotions? The Brain Meets the Robot

eware the passionate robot 345
what happens” is constrained by biological data linking behavior to anatomy
and neurophysiology, though without a necessary analysis of the underlying
genes. The aim is to discover relations between modules (neural circuits at
some grain of resolution) that implement basic schemas (functions, as distinct
from structures) in simpler species with those that underlie more elaborate
schemas in other species. Clearly, the evolutionary path described in
this way is not necessarily substantiated as the actual path of evolution by
natural selection that shaped the brains of the species we study today but
has two benefits: (1) making very complex systems more comprehensible
and (2) developing hypotheses on biological evolution for genetic analysis.
In 2003 I offered a conceptual evolutionary perspective on brain models for
frog, rat, monkey, and human. For rat, I showed how a frog-like taxonaffordance
model (Guazzelli, Corbacho, Bota, & Arbib, 1998) provides a
basis for the spatial navigation mechanisms that involve the hippocampus
and other brain regions. (As in Chapters by Rolls and Kelley, taxis [plural
taxes] are simple movements in response to a set of key stimuli. Affordances
(Gibson, 1966) are parameters for motor interactions signaled by sensory
cues without the necessary intervention of “high-level processes” of object
recognition.) For monkey, I recalled two models of neural mechanisms for
visuomotor coordination. The first, for saccades, showed how interactions
between the parietal and frontal cortex augment the superior colliculus, seen
as the homolog of the frog tectum (Dominey & Arbib, 1992). The second,
for grasping, continued the theme of parietofrontal interactions, linking
parietal affordances to motor schemas in the premotor cortex (Fagg & Arbib,
1998). This further emphasized the mirror system for grasping, in which
neurons are active both when the monkey executes a specific grasp and when
it observes a similar grasp executed by others. The model of human brain
mechanisms is based on the mirror-system hypothesis of the evolution of
the language-ready brain, which sees the human Broca’s area as an evolved
extension of the mirror system for grasping. In the next section, I will offer
a related account for vision and next note how dexterity involves the emergence
of new types of visual system, carrying forward the mirror-system hypothesis
of the evolution of the language-ready brain. The section ends with
a brief presentation of a theory of how human consciousness may have evolved
to have greater linkages to language than animal awareness more generally.
However, these sections say nothing about motivation, let alone emotion. Thus,
my challenge in the section From Drives to Feelings is to use these insights to
both apply and critique the evolutionary frameworks offered in Chapters 3–
5 by Kelley, Rolls, and Fellous & LeDoux and thus to try to gain fresh insight
into the relations between emotion and motivation and between feelings and
behavior. The mirror-system hypothesis, with its emphasis on communication,
provides one example of how we may link this brain-in-the-individual