Who Needs Emotions? The Brain Meets the Robot

how do we decipher others’ minds? 149
states are embodied (i.e., transcribed into bodily states) and to the extent
that their intentions, feelings, emotions, and attitudes can be read by an
external observer.
In this chapter, emphasis will be clearly put on communication between
selves at the embodied level. We will show how mental states of others can
be accessed through mind reading, a general human ability for understanding
other minds with the purpose of establishing communication with them.
From a philosophical point of view, a classical account of mind reading is
the simulation theory. Accordingly, it is thought that we exploit our own
psychological responses in order to simulate others’ minds or, in other words,
that we internally simulate others mental states in our own mind. The outcome
of this simulation process provides us with information about how
others think or feel by reading our own mind (Goldie, 1999; for a full account
of the philosophical issues raised by the simulation theory, see Davies
& Stone, 1995).
We will first describe experiments that support the notion of simulation
from a solipsist point of view, i.e., outside the realm of communication
with others. The reason for this choice is that most of the empirical arguments
for the simulation theory have been developed on the basis of how a
subject represents his or her own actions to him- or herself and, more specifically,
how the representation of actions reflects changes in brain activity.
We will extend the notion of simulation to the observation of others on the
basis of more recent experimental data which suggest that actions and emotions
of others can be represented by an observer to the same extent as he or
she represents his or her own actions. Finally, we will see that this mechanism
is not immune to errors of identification: simulation of one’s own mind
or of the minds of other individuals can yield to misattribution of mental
states in either direction, i.e., self-attribution of the mental states of others
as well as attribution to others of one’s own mental states.
THE SIMULATION THEORY IN THE SOLIPSIST CONTEXT
The simulation theory postulates that covert actions are in fact actions in
their own right, except for the fact that they are not executed. Covert and
overt stages represent a continuum such that every overtly executed action
implies the existence of a covert stage, whereas a covert action does not
necessarily turn into an overt action. As will be argued below, most of the
neural events which lead to an overt action already seem to be present in
the covert stages of that action. The theory therefore predicts a close similarity,
in neural terms, of the state where an action is internally simulated
and the state which precedes execution of that action (Jeannerod, 1994).