weakness in your left side and experience difficulties walking. For the
past three days, you have also had a more specific problem: Somehow,
you keep losing control of your left hand—it is acting on its own. Last
night, you awoke several times because your left hand was trying to choke you, and you had to use your right hand to fight it off. During the
day, your left hand sometimes unbuttons your hospital gown just after
your right hand has buttoned it up. Your left hand crushes the paper
cups on your tray or starts fighting with your right hand while you’re
trying to answer the phone. It’s an unpleasant situation, to say the
least—as if someone “from the moon” were controlling your hand.
Sometimes you wonder whether it has a mind of its own. What does it mean for something to “have a mind of its own”? Having
a mind means possessing inner states that have content and embedding
such thoughts and inner images of the world into a self-model.
Then the organism harboring them can know that they are occurring
within itself. So far, so good. But there is an important aspect of having a
mind of your own that we’ve not yet discussed: You also need explicit
representations of goal-states—your requirements, your desires, your
values, what you want to achieve by acting in the world. And you need a
conscious Ego to appropriate these goal-states, to make them your own.
Philosophers call this having “practical intentionality”: Mental states are
often directed at the fulfillment of your personal goals. Having a mind
means being not only a thinker and a knower but also an agent—an acting
self, with a will of one’s own.
That is where the Alien Hand syndrome, the neurological disorder
just described, comes in. The syndrome was first described in 1908, but
the term was not introduced until 1972, and it still isn’t clear what the
necessary and sufficient conditions in the brain for this kind of disorder
are. The alien hand crushing cups on the tray and fighting with
the healthy right hand seems to have a will of its own. When the alien
hand begins unbuttoning the patient’s gown, this is not automatic behavior
like the knee-jerk reflex; it appears to be guided by an explicit
goal-representation. Apparently a little agent is embedded in the bigger
agent—a subpersonal entity pursuing its own goals by hijacking a body
part that belongs to the patient. In another typical case, a patient will
pick up a pencil and begin scribbling with one hand, reacting with dismay
when she becomes aware of this. She will then immediately withdraw
the pencil, pull the alien hand to her side with her “good” hand,
and indicate that she did not initiate the scribbling herself. Another such case study describes the patient’s left hand groping for nearby objects
and picking and pulling at her clothes to the point that she refers to
her errant hand as an autonomous entity. These cases are interesting from a philosophical point of view, because
any convincing philosophical theory of the conscious self will
have to explain the dissociation of ownership and agency. Patients suffering
from Alien Hand syndrome still experience the hand as their own
hand; the conscious sense of ownership is still there, but there is no corresponding
experience of will in the patient’s mind. As philosophers say,
the “volitional act” is missing, and the goal-state driving the alien hand’s
behavior is not represented in the person’s conscious mind. The fact
that the arm is clearly a subpersonal part of the body makes it even more
striking to see how the patient automatically attributes something like
intentionality and personhood to it, treating it as an autonomous agent.
This conflict between the hand and the willing self can even become a
conflict between the hand and the thinking self. For instance, when one
patient’s left hand made a move he did not wish to make in a game of
checkers, he corrected the move with his right hand. Then, to his frustration,
the isolated functional module in his brain that was driving his
left arm caused it to repeat the unwanted move. Here is the philosophical problem: Is the unwanted move in the game
of checkers an action—that is, a bodily movement directly caused by an
explicit goal-representation—or is it only an event, something that just
happens, caused by something else? At one extreme of the philosophical
spectrum, we find denial of the freedom of will: No such things as “actions”
or “agents” exist, and, strictly speaking, predetermined physical
events are all that have ever existed. We are all automata. If our hardware
is damaged, individual subsystems may act up—a sad fact, but certainly
no mystery. The other extreme is to hold that there are no blind, purely
physical events in the universe at all, that every single event is a goal-driven
action, caused by a person—for instance, by the mind of God. Nothing
happens by chance; everything is purposeful and ultimately willed.
In fact, in some psychiatric syndromes, patients experience every
consciously perceived event in their environment as directly caused by
themselves. In other mental diseases, such as schizophrenia, one may feel that one’s body and thoughts are remote-controlled and that the
whole world is one big machine, a soulless and meaningless mechanism
grinding away. Note that both types of observations illustrate my claim
in chapter 1 that we must view the brain as a reality engine: It is a system
that constantly makes assumptions about what exists and what
doesn’t, thereby creating an inner reality including time, space, and causal
relations. Psychiatric diseases are reality-models—alternate ontologies
developed to cope with serious and often specific problems. Interestingly,
in almost all cases these alternate ontologies can be mapped onto
a philosophical ontology—that is, they will correspond to some wellestablished
metaphysical idea about the deeper structure of reality (radical
determinism, say, or the omnipotent, omnipresent God’s-eye view).
But to return to the original question: Do actions as such really exist?
A position between the two philosophical extremes would define “action”
as a particular kind of physical event. Most events in the physical
universe are only events, but an extremely tiny subset are also actions—
that is, events caused by an explicit goal-representation in the conscious
mind of a rational agent. Goal-states must be owned by being part of a
self-model. No Ego Tunnel, no action.
The alien hand, however, is not a distinct entity with an Ego Tunnel.
It is just a body part and has no self-model. It does not know about its
existence, nor does a world appear to it. Due to a brain lesion, it is
driven by one of the many unconscious goal-representations constantly
fighting for attention in your brain—plausibly, it is driven by visually
perceived objects in your immediate vicinity that give rise to what psychologists
and philosophers call affordances. There is good evidence
that the brain portrays visual objects not only as such but also in terms
of possible movements: Is this something I could grasp? Is this something
I could unbutton? Is this something I could eat or drink?
The self-model is an important part of the selection mechanism.
Right now, as you are reading this book, it is protecting you from these
affordances, preventing them from taking over parts of your body. If I
were to put a plate of your favorite chocolate cookies in front of you
and if you had the firm determination not to reach for it, how long
could you keep concentrating on the book? How long before a brief episode of Alien Hand syndrome would pop up and your left hand
would do something you hadn’t told it to do? The stronger and more
stable your self-model, the less susceptible you are to the affordances
surrounding you. Autonomy comes in degrees; it has to do with immunization,
with shielding yourself from infection by potential goal-states
in the environment.
The phenomenal experience of ownership and the phenomenal experience
of agency are thus intimately related, and both are important
aspects of the conscious sense of self. If you lose control over your actions,
your sense of self is greatly diminished. This is also true of inner
actions; for example, many schizophrenics feel that not only their bodies
but even their thoughts are controlled by alien forces. One of my pet
ideas for many years might well turn out to be true—namely, that thinking
is a motor process. Could thoughts be models of successfully terminated
actions but from a God’s-eye view—that is, independent of your
own vantage point? Could they be abstract forms of grasping—of holding
an object and taking it in, into your self? As I discuss in the chapter
on the Empathic Ego, there is solid empirical evidence showing that the
hand is represented in Broca’s area, a part of our brain that is of recent
evolution, distinguishes us from monkeys, and has to do with language
comprehension and abstract meaning. The thinking self would then
have grown out of the bodily self, by simulating bodily movements in an
abstract, mental space. I have been flirting with this idea for a long time,
because it would solve Descartes’ mind-body problem; it would show
how a thinking thing—a res cogitans—could have evolved out of an extended
thing, a res extensa. And this points to a theme running through
much of the recent research on agency and the self: In its origin, the Ego
is a neurocomputational device for appropriating and controlling the
body—first the physical one and then the virtual one.
There is a kind of agency even more subtle than the ability to experience
yourself as a coherent acting self and the direct cause of change:
This is what I call attentional agency. Attentional agency is the experience
of being the entity that controls what Edmund Husserl described as
Blickstrahl der Aufmerksamkeit—the “ray of attention.” As an attentional
agent, you can initiate a shift in attention and, as it were, direct your inner flashlight at certain targets: a perceptual object, say, or a specific
feeling. In many situations, people lose the property of attentional
agency, and consequently their sense of self is weakened. Infants cannot
control their visual attention; their gaze seems to wander aimlessly from
one object to another, because this part of their Ego is not yet consolidated.
Another example of consciousness without attentional control is
the dream state, and, as I discuss in the next chapter, the Ego of the
dream state is indeed very different from that of the waking state. In
other cases, too, such as severe drunkenness or senile dementia, you
may lose the ability to direct your attention—and, correspondingly, feel
that your “self” is falling apart.
Then there is cognitive agency, an interesting parallel to what
philosophers call the “cognitive subject.” The cognitive subject is a
thinker of thoughts and can also ascribe this faculty to herself. But often
thoughts just drift by, like clouds. Meditators—like the Tibetan
monks in chapter 2—strive to diminish their sense of self, letting their
thoughts drift by instead of clinging to their content, attentively but effortlessly
letting them dissolve. If you had never had the conscious experience
of causing your own thoughts, ordering and sustaining them,
being attached to their content, you would never have experienced
yourself as a thinking self. That part of your self-model would simply
have dried up and withered away. In order to have Descartes’ experience
of the Cogito—the robust experience of being a thinking thing, an
Ego—you must also have had the experience of deliberately selecting the
contents of your mind. This is what the various forms of agency have in
common: Agency allows us to select things: our next thought, the next
perceptual object we want to focus on, our next bodily movement. It is
also the experience of executive consciousness—not only the experience
of initiating change but also of carrying it through and sustaining a more
complex action over time. At least this is the way we have described our
inner experience for centuries.
A related aspect that bodily agency, attentional agency, and cognitive
agency have in common is the subjective sense of effort. Phenomenologically,
it is an effort to move your body. It is also an effort to focus
your attention. And it certainly is an effort to think in a concentrated, logical fashion. What is the neural correlate of the sense of effort? Imagine
we knew this neural correlate (we will soon), and we also had a precise
and well-tested mathematical model describing what is common to
all three kinds of experiencing a sense of effort. Imagine you are a future
mathematician who can understand this description in all of its intricate
detail. Now, given this detailed conceptual knowledge, you introspect
your own sense of effort, very gently, but with great precision. What
would happen? If you were to gently and carefully attend to, say, the
sense of effort going along with an act of will, would it still appear as
something personal, something that belongs to you?
The Alien Hand syndrome forces us to conclude that what we call the
will can be outside our self-model as well as inside it. Such goal-directed
movements might not even be consciously experienced at all. In a serious
neurological disorder called akinetic mutism, patients do nothing
but lie silently in their beds. They have a sense of ownership of their
body as a whole, but although they are awake (and go through the ordinary
sleep-wake cycle), they are not agents: They do not act in any way.
They do not initiate any thoughts. They do not direct their attention.
They do not talk or move. Then there are those cases in which parts of
our bodies perform complex goal-directed actions without our having
the conscious experience of these being our actions or our goals, without
a conscious act of will having preceded them—in short, without the
experience of being an agent. Another interesting aspect—and the third
empirical fact that any philosophy of the conscious self must explain—
is how, for instance, schizophrenics sometimes lose the sense of agency
and executive consciousness entirely and feel themselves to be remotecontrolled
puppets.
Many of our best empirical theories suggest that the special sense of
self associated with agency has to do both with the conscious experience
of having an intention and with the experience of motor feedback. That
is, the experience of selecting a certain goal-state must be integrated
with the subsequent experience of bodily movement. The self-model
achieves just that. It binds the processes by which the mind creates and
compares competing alternatives for action with feedback from your
bodily movements. This binding turns the experience of movement into the experience of an action. But note, once again, that neither the
“mind” nor the self-model is a little man in the head; there is no one doing
the creating, the comparing, and the deciding. If the dynamicalsystems
theory is correct, then all of this is a case of dynamical selforganization
in the brain. If for some reason the two core elements—the
selection of a specific movement pattern and ongoing motor feedback—
cannot be successfully bound, you might experience your bodily
movements as uncontrolled and erratic (or as controlled by someone
else, as schizophrenics sometimes do). Or you might experience them as
willed and goal-directed but not as self-initiated, as in the Alien Hand
syndrome.
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