Open Journal of Philosophy
2013. Vol.3, No.4, 435-442
Published Online November 2013 in SciRes (
Open Access 435
Phenomenal Consciousness and the Sensorimotor
Approach. A Critical Account
Alessandro Dell’Anna1, Alfredo Paternoster2
1Department of Philosophy, University of Genova, Genova, Italy
2Department of Arts Philosophy, Un iversity of Bergamo, Bergamo, Italy
Email: a_dellanna@ ho, alfr
Received July 17th, 2013; re vised August 17th, 2013; accepted August 2 5th, 2013
Copyright © 2013 Alessandro Dell’Anna, Alfredo Paternoster. This is an open access article distributed under
the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any
medium, provided the original work is properly cited.
The paper discusses some recent suggestions offered by the so-called sensorimotor (or enactivist) theo-
rists as to the problem of the explanatory gap, that is, the alleged impossibility of accounting for phe-
nomenal consciousness in any scientific theory. We argue in the paper that, although some enactivist
theorists’ suggestions appear fresh and eye-opening, the claim that the explanatory gap is (dis)solved is
much overstated.
Keywords: Sensorimotor Approach; Enaction; Phenomenal Consciousness; Externalism; Explanatory Gap
In this paper we shall discuss whether the sensorimotor
approach to perceptual experience, in its different versions
(O’Regan & Noë, 2001; Noë, 2004; Thompson, Palacios, &
Varela, 1992; see also Hurley, 1998) has the theoretical re-
sources to address the problem of consciousness, and in par-
ticular the so-called explanatory gap, as some of its propo-
nents argued ( see e.g. O’Regan, Myin, & Noë, 2005; Thomp-
son, 2005; Thompson & Varela, 2001). We shall argue that
the sensorimotor approach provides some evidence for the
role of external (non-cranial and extra-bodily) factors in the
“production” of conscious experience, thereby restating the
issue to some extent, but it is not able to definitely remove,
or deflate, the so-called explanatory gap.
In the first section we shortly introduce the sensorimotor
account, focusing on the aspects relevant to the issue of con-
sciousness. The second section is devoted to a critical dis-
cussion of the two main arguments offered by sensorimotor
theorists aiming to show that the explanatory gap can be re-
moved or explained away. In the third section we qualify the
kind of externalist strategy pursued by sensorimotor theorists
to deal with the problem of conscious experience and we
assess to what extent it is successful. In the fourth section we
discuss a different strategy for dealing with the problem of
consciousness in the sensorimotor framework. In the last
section we draw some conclusion s.
The Sensorimotor Account of Perceptual
Although the expression “sensorimotor account” was intro-
duced by O’Regan and Noë (2001) and, narrowly interpreted, it
denotes their specific view on perception, in a broader sense we
can regard the sensorimotor approach as a family of theories
agreeing on a critical attitude as regards computational theories
of perception (and to classical computationalism in general).
Sensorimotor theories include the approach of enactive vision
(see e.g. Thompson, Palacios e Varela, 1992; Noë, 2004;
Thompson, 2007), the research program of animate vision
(Ballard, 1991, 1996) and the behavior-based approach (or
situated robotics: Brooks, 1991, 1999). Dynamical approaches
to cognitive science (for instance, Thelen, & Smith, 1994;
Kelso, 1995) can also be traced back, in certain aspects, to the
sensorimotor paradigm.
In this paper we focus on those versions of the theory that are
most relevant to the issue of consciousness, that is, the sen-
sorimotor approach in the narrow sense of the term or the
so-called enactive vision. The core of this view can be charac-
terized by the conjunction of the two following theses:
1) Perception is the activity of exploring the environment, an
activity which is carried out by exploiting a systematic interde-
pendency of sensorial information and motor behavior. Much in
the spirit of ecological optics (Gibson, 1979), every kind of
action structures the optic array (in the case of vision) in a pe-
culiar lawful way.
2) Perception is constituted by, rather than merely depending
on, the possession of sensorimotor knowledge. This knowledge
consists in the ability to perform movements appropriate to a
successful “navigation” of the environment, including in this
latter notion the pursuit of basic ecological goals such as
grasping an object. Sensorimotor knowledge is tacit and deter-
mined by bodily structure.
Taken together, these two theses can be summarized by say-
ing that perception is a kind of activity that is performed thanks
to the possession of a certain kind of physical competence or
ability, a kind of bodily know-how. What we perceive is deter-
mined by what we do, and what we do is part of the perceptual
The leading intuition in the sensorimotor view is that there is
a sort of loop in our sensorimotor relation to the world: on the
one hand, changes in the stimulation modify our experience-
things appear different; on the other hand, agents’ movements
change the stimulation (and experience as well). Indeed chan-
ges in the stimulation typically require agents to move, for ex-
ample, in order to keep a moving object in the focus of atten-
tion. It is for this reason that the content of sensorimotor ability
consists essentially of the knowledge of how one has to move
in order to track changes. We could say that an important com-
ponent of perception is anticipatory, since agents are competent
in the sensorimotor domain to the extent they know how stimu-
lation will change following movement. Changes in stimulation
according to variations of the body (and vice-versa) are called
“sensorimotor dependencies”, or (less perspicuously) “sensori-
motor contingencies”.
An important implication of such a view is that perception is
not a brain process, but, rather, a competent activity performed
by the whole animal. This is the main point of departure from
(classical) computationalism, which tended to identify the per-
ceptual system with a part of the nervous system (though de-
scribed at an algorithmic level).
Now, whatever may be the other merits and shortcomings of
the computational approa ch in the domain of perception, it must
be recognized that computationalism has many difficulties in
dealing with consciousness. The basic reason for this is that
computational functionalism has deliberately put aside the con-
scious aspect of mental processes, in at least three senses. First
of all, whether a process is conscious or not is definitely not
relevant for a computational theory. In fact, computational
theories are typically descriptions of subpersonal processes.
Perhaps some pieces of these processes emerge at the level of
consciousness, but this is not necessary and does not make a
difference for the functional-computational nature of the proc-
ess. Second, some authors have explicitly endorsed the assump-
tion that the best strategy for addressing the study of mind is to
separate intentionality (or “content”) from consciousness (cf.,
for instance, Dennett, 1969; Fodor, 1980). As a matter of fact,
this separation has for many years involved addressing just
intentiona lity, leaving consciousness apart. Third, paradigmatic
phenomenal states, such as pain, can hardly be accounted for in
purely functional terms; so, computational theories, qua func-
tional, are not able to deal with phenomenal states, or with the
phenomenal aspect of mental states. In a nutshell, in the com-
putational account consciousness turns out to be a bothersome
Of course there is a ruthless way to reply to these considera-
tions, consisting of the rejection of the premise according to
which there is something like a phenomenal quality to account
for (Dennett, 1991, 2005). Although we believe that Dennett is
right on some important points (cf. infra), it seems to us that the
concept of phenomenal consciousness cannot be simply ruled
out in the way it is by Dennett.
Are sensorimotor approaches in a better position to deal with
the problems of consciousness? We shall consider, to begin
with, some arguments put forward by the most representative
supporters of the sensorimotor approach (Hurley, 1998; Hurley
& Noë, 2003; Noë, 2004; Noë & Thompson, 2004; O’Regan,
Myin, & Noë, 2005; Myin & O’Regan, 2008)—what Clark
(2008) calls the “strong sensorimotor approach”. These argu-
ments aim to show that the sensorimotor approach is able to
close, or at least to deflate, the “explanatory gap”, that is, the
alleged impossibility of accounting for phenomenal conscious-
ness in terms of whatever scientific (psychological or neuron-
logical) explanation (Levine, 1983; Chalmers, 1996).
Two Arguments for Removing
(or Explaining Away) the Explanatory Gap
The core intuition of enactivists as to the problem of the ex-
planatory gap can easily be stated in a phrase: (phenomenal)
consciousness does not come from the brain, so there is no
explanatory gap at all, since the alleged gap is regarded to be
between the brain and the person. The idea is that if one gives
up the assumption that consciousness supervenes only onto the
brain, then there is no gap any longer: the question how could
such and such neural state give rise to such and such feeling is
misleading, because, although the neural state has a causal role
in producing the feeling, it does not exhaust the base of super-
venience. Brains are at most a causal (but not constitutive) fac-
tor of consciousness, since, “rather than directly producing phe-
nomenal experience, neural activity is involved in phenomenal
experience because of what it allows organisms to do” (O’Re-
gan, Myin, & Noë, 2005: p. 371), and “the perceived quality of
sensory stimulation is determined by the particular way subjects
interact with their surroundings rather than by the specific
character of any intervening brain processes or representations”
(Myin & O’Regan, 2008: p. 192).
Why should we believe that the supervenience base of “the
perceived quality” includes (to say the least) bodily know-how
and external factors? It seems to us that two main arguments
can be traced in the discussion of sensorimotor theorists: the
argument from the virtual nature of experience (briefly, the
argument from virtual experience), and the argument from sen-
sory substitution (which we call, for brevity, the “TVSS argu-
ment”, since the discussion usually concerns Paul Bach-y-Rita
(1972) Tactile Vision Sensory Substitution system). Let us
discuss each of them, one at a time.
The Argument from Virtual Experience
According to sensorimotor theorists experience is virtual in
the sense that experience is in part constituted by what one
could do, rather than being only constituted by actual feelings.
For example, when your fingers are in contact with some points
of the surface of an object, you have the sensation of perceiving
the object as a whole, i.e., you have the feeling of grasping the
entire object, although you are actually in contact only with
some parts of its surface. This is an instance of the general,
well-known phenomenon of amodal completion (see e.g.
Kanizsa, 1979). On the sensorimotor view, amodal completion
can be explained by our knowing what we could do with the
object by exploring it, that is, by our sensorimotor ability
(O’Regan, Myin, & Noë, 2005). The same explanation is taken
to account also for a different kind of “completion”, the fact
that we do not experience any “visual gap” although there is the
so-called blind spot (“macula cieca”) in the retina: we have
visual experiences of certain features that are actually not pre-
sent in the proximal stimulation, since they would fall in the
region, devoid of photoreceptors, where the optic nerve departs.
Therefore, it could be argued that the experience of an object
depends on the sensorimotor knowledge, rather than being di-
rectly provided by some neural activity. Far from being consti-
tuted by what actually happens, experience is in part constituted
by what one could do, something that, as virtual, cannot have
an actual cerebral realization. As Alva Noë put it, “my sense of
the perceptual presence of items at the periphery of my visual
Open Access
field… is not a sense that I actually see these features, but that I
have access to them, due to the fact that my relation to them is
mediated by patterns of sensorimotor contingency” (2004: p.
216, our italics). One can talk about a perceptual virtual pres-
ence since, even if one cannot really see a virtual item, one has
rather some (normally satisfied) expectations: virtual presence
is a dispositional property which, however, is usually made
actual some instants later.
The argument of virtual experience is strengthened by the
remark that perceptual experience has two phenomenal features.
First, sensorial information suddenly changes as soon as one
performs the slightest movement. This property, called by
O’Regan, Myin & Noë (2005) “corporality”, or “bodiliness”,
would explain the “intimate” quality of perceptual experience:
“because sensory information is so exquisitely sensitive to body
motions, it is almost as though it were part of you” (ibid., p.
374). The second feature, called “alerting capacity” or, in other
essays, “grabbiness” (see e.g. Myin & O’Regan, 2008), consists
of the very fast focalization of attention when there are sudden
changes in the stimulation. In the visual case, for instance, a
change in the visual field triggers a movement of the eye so that
the fovea turns out to be lined up to the location of the change.
Thus, a visual variation is immediately recognized and ana-
lyzed. Grabbiness makes all parts of the visual field very vivid
and present (again, intimately related to us). In this way, certain
qualitative aspects of experience—those aspects that make the
experience mine (cf. e.g., Metzinger 2003)—are explained in
terms of objective features of the way our perceptual systems
It is not very clear whether the notions of corporality and
grabbiness are intended to be applied to the “real” experience
rather than to the virtual one. They are perhaps better to be
considered as further evidence for the thesis that the superven-
ience basis of (phenomenal) consciousness is crucially consti-
tuted by sensorimotor competence, i.e., by a bodily know-how.
Be that as it may, the phenomenon of virtual presence would
show that experience does not supervene on neural facts, since,
for instance, the hidden face of a perceived object is not actu-
ally available to photoreceptors nor, then, to the brain. Of
course there are some parts of the experiential content which
are “actual”, but the point is that the possibility of being present
to consciousness despite not being available to receptors is a
sufficient condition to show that (in general) experience need
not possess a cerebral basis. As we said above, the problem of
the explanatory gap would vanish insofar as sensation is not
regarded as being supervenient on neurophysiological patterns.
It is worth to point out that this argument concerns specifically
perceptual experience, as opposed to the experience of having a
thought, or to the experience of pain. Thus, even if the argu-
ment were sound, it would be limited in scope.
Now, it could be replied, first of all, that the most plausible
causal source of the fact that something is present to con-
sciousness, despite not being really (“objectively”) present in
the portion of environment available to receptors is after all the
brain. The hypothesis that the alleged virtua l part of expe rience
is produced by the brain not only makes sense, but seems
(prima facie) to be the most likely one, as is particularly appar-
ent in the case of the blind spot (see, e.g., Churchland &
Ramachandran, 1996).
It must be conceded, however, that the case of blind spot is
not exactly analogous to the case of amodal completion (the
notion of virtual seems to fit better the latter rather than the
former), and that there is at least some plausibility in the enac-
tivist account of amodal completion. For, as we said above,
there is a clear sense in which a hidden part is not actually
available to the brain despite of being phenomenally “avail-
able” (to the whole person). As far as the issue of the nature of
the supervenience basis is concerned, it is not very clear who
has the burden of proof.
However, even if one grants this point to sensorimotor theo-
rists, the argument from virtual experience seems to face an-
other serious difficulty. Clark (2009) discharges the argument
from virtual experience for—he claims—it faces the following
dilemma: either experience is only in part virtual, or experience
is entirely virtual. If the former, then the explanatory gap is still
there because we need an explanation of how the real (=
non-virtual) experience is produced. If the latter, the problem is
that we lack a clear justification of the claim that experience is
always virtual, which appears (at least prima facie) hardly be-
lievable. Noë (2006) claimed that experience is virtual “all the
way in” (p. 421), but, as Clark correctly points out, this is ab-
solutely obscure. Even if what is meant by Noë is that “what
fixes any experience is not a snapshot moment of neural activ-
ity but a process extended in time (…) then all that seems to
matter is that the neural activity evolves over time in such-
and-such way” (Clark, 2009: pp. 974-975).
In sum, what the argument from virtual experience at most
shows is that there are non-cranial factors which are relevant to
explain the phenomenon of virtual experience, but this does not
undermine at all the thesis that non-virtual experience is deter-
mined by the cerebral machinery.
The TVSS Argument
Sensorimotor theorists take the experiments on the so-called
sensory substitution systems, such as the famous, pioneering
TVSS (Bach-y-Rita, 1972), as further evidence for the thesis
that consciousness is not (only) produced by the brain. In the
TVSS blind subjects are able to feel visual-like experiences
through a tactile perception system arranged on their shoulder.
For instance, a typical visual feature echoed in their experience
is spatial localization: after training, subject feel the objects
located in the external space, rather than in their skin; and they
entertain typical visual feelings such as parallax, zoom, per-
spective. As Hurley & Noë (2003) point out, in structural re-
spects TVSS-perception after adaptation is more like vision
than it is like touch. In fact, both in ordinary vision and in
TVSS-vision, we make perceptual contact with objects arrayed
out before us at a distance in space: unlike touch, there is no
immediate physical contact with perceptual objects.
Why are sensory substitution systems taken to provide evi-
dence for the failure of supervenience of experiential content
onto the brain? Because they would seem to show that the qual-
ity of experience does not depend on the activity of some spe-
cific brain areas, but, rather, on the sensory system organization.
According to O’Regan, Myin & Noë (2008), for instance, neu-
ral activation is just a way to code information, and it is hard to
see why neural activation in (brain-area) A rather than in B
should make a difference in perceptual quality; intermodal dif-
ferences in experiential quality are better explained by differ-
ences in sensorimotor dependencies. Thus, the prediction is that,
if we replace one sensory system (say, a visual system) with
another (say, a tactile one) and keep the sensorimotor depend-
encies of the former, we shall obtain the quality of the former.
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The crucial point is that TVSS is a “quasi-visual” modality
since it shares with vision a common sensorimotor structure.
“Changes in qualitative expression are to be explained not just
in terms of the properties of sensory inputs and of the brain
region that receives them, but in terms of dynamic patterns of
interdependence between sensory stimulation and embodied
activity. What drives changes in qualitative expression of a
given area of cortex (…) is not simply a remapping from the
sources of input, whether internal or external, to that area of
cortex, but rather higher-order changes, in relations between
mappings from various different sources of input to different
areas of cortex and from cortex back out to effects on those
sources of input, which are in turn fed back to various areas of
cortex” (Hurley & Noë, 2003: p. 146).
However, the quasi-visual nature of the TVSS experience
can seriously be called into question: if it is true that some vis-
ual features are actually reproduced, other salient visual fea-
tures, such as color, are not, and, on the whole, the quality of
the TVSS-experience is still quite different from “normal” vis-
ual experience–in a word, TVSS subjects do not really see, as
Bach-y-Rita himself was quite ready to concede.
Of course, supporters of the sensorimotor paradigm are well
aware of this difficulty. They reply by saying that the partial
inadequacy of the TVSS as a visual tool depends, at least in
part, on the fact that the system is not sophisticated enough.
Moreover, they reject the idea that visual experience is a matter
of “all or nothing” (O’Regan & Noë, 2001: p. 958): it is true
that color and stereo vision are absent, and resolution is ex-
tremely poor. But, just as color blind, stereo blind, one-eyed or
low-sighted people can be said to “see,” people using the TVSS
should also be said to see. Seeing with the skin probably in-
volves laws that are not exactly the same as seeing with the
eyes, just as seeing colors in the dark is not quite the same as in
the light1.
Yet, quite independently of the way the experiential quality
of the TVSS is assessed, it seems to us that the role played by
the brain in the production of experience is underestimated:
even if one acknowledges that neural activation is just a way of
coding information, still the fact that certain areas receive pro-
jections from, say, A-receptors rather than B-receptors, does
make a difference, and this is an internal difference. There is no
compelling evidence from the TVSS for the failure of super-
venience of experiential content onto the brain2. Today we
know that there are many projections from cortical areas back
to the periphery of the nervous system, so it comes not as a
surprise that knowledge flowing from the center permeates
what the senses detect. Moreover this would corroborate the
anticipatory character of sensorimotor knowledge, that Noë
himself is emphasizing, and is coherent with an important re-
mark O’Regan and Noë (2001: p. 944) make in order to clarify
the sensorimotor contribution to consciousness: “For a creature
(or a machine for that matter) to possess visual awareness, what
is required is that, in addition to exercising the mastery of the
relevant sensorimotor contingencies, it must make use of this
exercise for the purpose of thought and planning” (our empha-
sis). That is, the simple exploitation of a sensorimotor contin-
gency remains a sub-personal process, whereas its merging
with thought processes makes it poised for consciousness. We
assume that thought processes, qua higher-order mental proc-
esses, are implemented in higher areas of the brain, providing
the feedback that a virtual presence, as Noë would have it,
might require.
Clark (2009) has an even stronger reply to the argument from
TVSS. He claims that the argument from TVSS falls into the
fallacy of mistaking a causal property for a constitutive prop-
erty. As he put it, the argument from TVSS “depends on taking
evidence for the role of whole sensorimotor loops in training
and tuning the neural systems that support conscious perception
for evidence of the ongoing role of such loops (…) in conscious
perception itself” In other words, consciousness depends on
neural modifications; sensorimotor loops are the causal sources
of these modifications, but the “real work” is made by neural
circuits: if neural circuits were not affected by sensorimotor
loops, the quasi-visual consciousness would hardly be pro-
The causal-for-constitutive fallacy is familiar in the debate
on (various kinds of) externalism in philosophy of mind. Indeed,
the typical argument for externalism on intentional content rests
on the intuition that a difference in the environment can make a
mental difference despite of all internal factors being equal3.
Internalists, however, can reply to this that a difference in en-
vironment makes a mental difference only provided that the
environmental difference is taken into account by sensory sys-
tems. For instance, if a change in a distal condition does not
yield a corresponding change in the proximal stimulus—in the
retinal image—intentional content will not change (see, e.g.,
McGinn 1989). Of course, an environmental change normally
determines a proximal change, but this is not the case in the
counterfactual hypothesis set out in thought-experiments. In-
deed, in order to test our intuitions on how intentional content
should be individuated, modal considerations are crucial. When,
as usual, there is a causal chain of events which determine, in
the end, a certain kind of mental event, all the links of the chain
are causally relevant, but the distal cause—the environmental
condition—is “screened off” by the proximal condition. That’s
why the distal condition has a causal but not constitutive role,
as the counterfactual scenario makes explicit.
Yet, there is a move available to externalists, and they actu-
ally made it: they can argue that our ways to ascribe mental
contents imply that the distal/causal element is part of the in-
tentional content. That would make the distal causal factor
content-constitutive. Is this reasonable? And, supposing it is so,
is this move available even in the case of phenomenal content?
Sensorimotor Accounts and Varieties of
We saw two arguments aiming to show that the sensorimotor
approach can remove or dissolve the explanatory gap, and we
rose some doubts on the plausibility of these arguments. Maybe
other arguments can be reconstructed from the examples dis-
cussed by enactivist scholars (see, e.g., what Clark 2009 calls
the “argument from the variable neural correlate”), but, in es-
sence, all sensorimotor considerations and examples are in-
stances of one and the same strategy: arguing for some kind of
1Indeed, it could be argued that the TVSS is a new kind of sensory system,
neither visual nor tactile.
2The experiments on rubber arms (see e.g. Botvinick & Cohen,1998;
Ramachandran & Blakeslee, 1998) are also regarded as (perhaps equally
controversial) cases against the brain supervenience of phenomenal con-
3Here we are r eferring to percep tual content. We leave apart belief co ntent.
Perspectives of externalism are arguably worse in the case of belief content.
Open Access
externalism as to phenomenal facts.
Externalism on phenomenal facts is regarded as a sufficient
condition for removing the explanatory gap4. Therefore, two
questions are in order here: 1) do the arguments from virtual
experience and from TVSS provide evidence for endorsing
externalism of phenomenal consciousness? 2) Is externalism of
phenomenal conte nt indeed sufficient for c losin g t he gap?
As we are going to argue, our answers are “maybe” (or, “it
depends”) to the first question, and “not at all” to the second
one. Even if one wishes to concede that some version of exter-
nalism as to phenomenal facts is true, still it is hard to under-
stand why externalism of phenomenal content should be suffi-
cient for dissolving the explanatory gap, since to say that the
brain does not exhaust the supervenience base does not amount
to say, of course, that brain is not involved at all.
We could describe the situation as follows. According to
sensorimotor theorists, the content of perception is determined
by sensorimotor ability (or competence), and sensorimotor
ability involves crucially external factors, thereby justifying
externalism as to phenomenal content. However, there are two
problems. First, the enactivist strategy faces the following di-
lemma: either sensorimotor competence is a (genuine kind of)
knowledge represented in the brain, or sensorimotor compe-
tence is distributed (rather than represented) as is claimed, for
instance, in the extended mind model (Clark & Chalmers,
1998). If the former, of course, externalism fails and the ex-
planatory gap is still there (this corresponds to the causal/con-
stitutive fallacy); therefore, we can take for granted that sen-
sorimotor theorists endorse the second horn of the dilemma.
And here we face the second problem: enactivists have to show
that the external “components” of sensorimotor ability deter-
mine also the phenomenal aspect of perceptual content.
As we saw in the previous section, however, the inference
from the cases discussed by sensorimotor theorists to external-
ism as to phenomenal content (please take hereafter the expres-
sion “phenomenal content” as short for “phenomenal compo-
nent of mental content”) cannot easily be drawn. Moreover,
there are different kinds of externalism: at the very least, vehi-
cle externalism and content externalism. So, it is perhaps a
good idea trying to deepen the kind of externalism involved
here, assessing whether the relevant kind of externalism can
actually vindicate the claim according to which the explanatory
gap is removed.
Let us suppose, to begin with, that the sensorimotor approach
is committed to externalism about intentional content. The idea
of enactivists seems to be that it is impossible to disentangle
purely intentional aspects from purely phenomenal aspects (see
e.g. Noë, 2004: Chap. 3). Or, perhaps, they think that there are
no phenomenal properties that are not intentional either (but see
below). Yet there are many authors (for example, Chalmers,
1996) who take phenomenal properties as not supervenient on
intentional properties. If these authors were right, externalism
about intentional content would not imply externalism about
phenomenal content. Therefore, two possibilities are open to
the sensorimotor theorist: either she endorses the intentionalist
theory of mental states, according to which phenomenal proper-
ties can be reduced to intentional properties—there are no phe-
nomenal properties over and above the intentional ones—or she
can try to show that even phenomenal properties (qua distinct
from the intentional ones) are not supervenient on cerebral
The second strategy is not much promising, because, as we
saw in the previous section, the standard strategy to vindicate
content externalism consists in claiming that a distal causal
factor is constitutive of content; however, if this could sound
reasonable for intentional content (at least in the case of per-
ception), it is not equally plausible for phenomenal content. In
fact the very idea of distinguishing intentional aspects from
phenomenal aspects gives a prima facie reason for thinking that
the latter supervenes on purely internal factors. In any case, as
we saw in the previous section, it is hard to find in the enactiv-
ist essays an argument for thinking otherwise.
As to the first strategy, it would arguably be more promising.
However, there is no clear evidence that it is endorsed by sen-
sorimotor theorists. After all, they present their view as also
able to account for phenomenal consciousness, i.e., for the
qualitative properties; this seems to suggest that they are dis-
posed to acknowledging some kind of (non-reducible) differ-
ence between intentional aspects and phenomenal aspects.
Moreover, if they were actually intentionalist (that is, if they
held that phenomenal states can be reduced to externally indi-
viduated intentional states), then, in order to remove the ex-
planatory gap, they could simply argue for a functionalist
treatment of intentional content—of course the relevant kind of
functionalism would be a wide one (cf. Wilson 2004)5.
In sum, the inferenc e from external ism on intent ional conten t
to externalism of phenomenal content does not seem to be a
much manageable strategy for the sensorimotor theorist. Even
if enactivists are certainly committed to perceptual content ex-
ternalism, there is no easy way from here to the removal of the
explanatory gap. Let us take into consideration, then, vehicle
Enactivists are clearly committed to vehicle externalism.
This commitment is a consequence of the thesis that perception,
far from being a linear bottom-up processing flow, is a collec-
tion of looping interactions involving neural circuitry (connect-
ing “higher” to “lower” brain areas, and encompassing both
cognitive and motor systems) and bodily actions (Hurley, 1998;
cf. also Clark, 2009: Section 5). On this view, the physical ve-
hicles of experiential content (so, the subpersonal processes and
events) are extended dynamic loops7.
5Arguably, the insistence on the temporal dimension of experience and the
related remark that taking experience as a sequence of “snapshots” is mis-
leading make somewhat unpalatable the notion of content itself (but it is
worth to point ou t that Noë, 2004 uses syste matically the word “content” ).
6Sometimes, sensorimotor theorists appear to be inclined to eliminativism.
Cf. e.g., “There is no explanatory gap. We do not claim that it is possible to
explain the physical basis of conscious experience by appeal to sensorimotor
contingencies. How, one might ask, can sensorimotor contingencies explain
henomenal consciousness any better than other proposals that have been
made? Rather, we argue, as should by now be clear, that the conception o
phenomenal consciousness itself must be (and can be) rejected, and so there
is no longer any puzzle about how to explain that ” (O’Regan & Noë, 2001:p
963). This oscillation (which can also be attributed to Dennett,1991) can
erhaps be explained by different interpretations of what one means by
“experiential properties”. For instance, O’Regan & Noë (2001:p. 960) hold
that it is one thing to say that (perceptual) experience has a qualitative char-
acter, and quite another to say that there are some properties, the qualia o
experiential states: qualia do not exist, whereas the so-called experiential
states are actually ways of acting; experience is something we do and its
qualitative features are a spects of this activity.
4Since ther e are many v ers io ns o f ext ernal ism, t hi s cl aim sh oul d be q ual ifi ed
(see infra). F or the moment, by “externalism o f ph enomenal facts” we intend
the thesis that phenomenal consciousness does not supervene on the brain
Open Access 439
Now, we think that this view is a bit vague, and that much
research has still to be done in order to get a reasonably clear
picture of how all this works (the traditional picture is perhaps
wrong, but is much clearer). However, independently of what
are the perspectives for the dynamical systems theory in cogni-
tive science—the kind of models clearly implied by the ex-
tended loops view—one can suppose that extra-cranial factors
are part and parcel of the processes underlying our perceptual
Suppose, then, to grant all that. We could still ask whether
this is enough to claim that the explanatory gap is removed. It
seems to us that it is sufficient to escape the causal-constitutive
fallacy, but not sufficient to remove, or deflate, the explanatory
gap, since the brain is still a relevant component of the process.
Patently, nothing in the extended dynamic loops picture allows
to rule out the possibility that the minimal machinery underly-
ing conscious experience is limited to the processes running
into the brain.
Sensorimotor Subjectivity
Evan Thompson (2005, 2007) has recently put forward an
original proposal which, although belonging to the same sen-
sorimotor/enactive framework illustrated in the first paragraph,
differs from it in some aspects. We will offer two criticisms of
this proposal. They are strictly related, but whereas the former
has to do with Thompson’s hypothesis of a “pre-reflective bod-
ily self-consciousness” (PBSC from now on), the latter deals
with the primacy of the first person perspective (with respect to
the third person), that the author seems to advocate in cognitive
science (in Dennett’s 1991 terms, we could talk of the primacy
of phenomenology over heterophenomenology).
Thompson introduces the concept of PBSC as the solution to
the “body-body problem”, that is, the problem concerning the
relation between the lived-body, the body as a subject of action
and cognition, and the living-body, the body as a biological
object. According to Thompson (2005: p. 409), if the problem
of consciousness is put this way, the gap is no longer “between
two radically different ontologies (physical and mental), but
between two types within one typology of embodiment (subjec-
tively lived body and living body)”. Filling this gap seems to be
much less hard. The notion of PBSC would allow the re-con-
nection of the living body—the body as an observable ob-
ject-with the lived body, i.e., the body as a subject, the tran-
scendental condi t i o n8 for the living body itself.
There is indeed a clear difference between feeling our own
arm while we are touching it with our hand and feeling our
hand touching the arm. But we maintain that the main short-
coming of the concept of PBSC is exactly the same as that of
the Kantian transcendental; that is, its formal character, or, in
other words, its empirical emptiness. Supposing that the body-
body problem is a more tractable problem than the mind-body
(mental-physical) one, it is not at all clear why postulating a
PBSC (as Kant postulated an “I THINK that must be able to
accompany every representation of mine”) should be a more
satisfactory solution. In fact, the problem seems in this way to
be displaced rather than solved: from the subjectivity of the
lived body to the PBSC9.
Establishing an analogy between the concept of PBSC and
the concept of “biological selfhood”, typical even of the most
elementary forms of life-the prokaryotes-cannot be of any help
either. This kind of selfhood, according to Maturana and Varela
(1987)’s autopoiesis thesis (to whom Thompson appeals here),
rests upon the distinctive autonomy of living systems, which
consists in their being constituted by their own biological proc-
esses. These processes neatly separate the organism, producing
boundaries/membranes, from the rest of the world. In multicel-
lular organisms endowed with a nervous system (metazoans,
that is, animals), the biological identity is determined by the
way the brain cyclically couples movement and sensory infor-
mation (by means of the above-mentioned “sensorimotor
loops”), disclosing a point of view or a perspective on the world
(2005: pp. 418-419). It is worth to point out that, according to
the autopoiesis thesis, biological processes are cognitive proc-
esses, so much so that there’s no need for an organism to be
endowed with a nervous system in order to have knowledge (of
course, here we are dealing again with a sort of knowing-how,
rather than a knowing-that). But, if so, what are the origin and
the function of this alleged PBSC? Are humans the only organ-
isms endowed with it? Maybe primates? Animals in general? It
is not at all clear.
Note that, so far, Maturana, Varela and Thompson’s picture
does not seem to diverge from the account offered by Dennett,
an author still sympathetic to the computational paradigm. In-
deed, talking about the first forms of replicators, which are
similar to the first forms of living being, prokaryotes, Dennett
“When an entity arrives on the scene capable of behavior that
staves off, however primitively, its own dissolution and de-
composition, it brings with it into the world its ‘good’. That is
to say, it creates a point of view from which the world's events
can be roughly partitioned into the favourable, the unfavourable
and the neutral. And its own innate proclivities to seek the first,
shun the second and ignore the third, contribute essentially to
the definition of the three classes. As the creature thus comes to
have interests, the world and its events begin creating reasons
for it—whether or not the creature can fully recognize them”
(1991: p. 189).
But, once such a minimal biological selfhood is accepted, ei-
ther the concept of PBSC turns out to be redundant, given that
it doesn’t add much to it, or, as we said, it is empirically vacu-
ous, since it merely postulates a formal (conscious) unity sim-
ply superimposed on the biological identity. In both cases
PBSC lacks any explicative power.
This corroborates our judgment that the capacity of sensori-
motor theories to deal with the explanatory gap depends essen-
tially on the endorsement of vehicle externalism, notwithstand-
ing Thompson’s insistence on his being able to explain the
subjective side of experience by means of PBSC. One could say,
indeed, that Thompson’s argument entailing the presence of a
subjective pole in front of an objective one (holding intentional
7According to Clark (2009), this argument from “dynamic entanglement” is
the best argument for the externalism of phenomenal content. More on this
in next section.
8Here Thompson (2005: p. 410) refers explicitly to the notion of “transcen-
dental” in Kant, remarking that within the phenomenological tradition (in
particular Merleau-Ponty and Husserl) the transcendental is identified with
the function of the live d-body.
9Our remark is sympathetic with Dennett’s (2007: p. 267) criticism of the
same concept: “What is this remarkable implicit awareness or pre-reflective
self-consciousness? Thompson doesn’t say […] I want to substitute ‘Newto-
nian’ qu estions: what do es implicit awar eness do? […] What ki nd of things
can a sub ject do that she wouldn’t be able to do if it weren’t for the gift o
pre-reflective self-consc iousness?”
Open Access
and phenomenal aspects together, as hypothesi zed by the int en-
tionalist account) is logically valid: if we represent conscious-
ness as a two-place relation, once we identify an object, we
have to admit a subject who is conscious of that object. He
writes (2005: p. 420) that, when I touch a bottle “The inten-
tional object of my tactual experience is the bottle, but at the
same time I live through my grasping feeling in a non-inten-
tional (non-object-directed) manner. To experience the feeling
as mine I do not have to identify it as mine. Instead the feeling
comes with an intrinsic ‘mineness’ or first-personal giveness
that constitutes its subjectivity”. But, again, Thompson is not
clear about which requirements are needed in order to have a
PBSC. Is it enough to have a body without a nervous system? It
doesn’t seem so, because, as we saw, the role of the nervous
system is to couple sensory surfaces and effectors already to the
aim of preserving the biological selfhood. But, then, Thompson
cannot use twice this description, once for the biological self-
hood, and the second time for the PBSC. Is the involvement of
the environment also necessary for the PBSC? But, if so,
Thompson should give us a deeper account of his standpoint
with regards to active externalism (see above).
We agree, on the other hand, with Thompson (2005: p. 424)
in rejecting O’Regan and Noë’s claim that everything outside
of the focus of attention is not conscious (2001: p. 964). This in
fact presupposes an “all-or-nothing” view of consciousness that,
on the other hand, O’Regan and Noë themselves criticize in
other passages. Take Block’s famous example10, in which a
background noise never heard up to that point by a man ab-
sorbed in a conversation is suddenly noticed, and recognized as
having been heard even before it was noticed. Thompson re-
jects both Block’s (1997: p. 386) interpretation, according to
which the man was phenomenally conscious of the noise,
without having access consciousness of it, and O’Regan and
Noë’s interpretation, according to which, since you can’t have
phenomenal consciousness without access consciousness, the
man couldn’t be conscious of the noise before noticing it.
Thompson thinks that the man had some conscious access to
the noise because consciousness (PBSC) comes in a series of
degrees, that is, has a graded structure, which should not be
collapsed on the extreme pole of attention, the point in which
the man comes up and exclaims “there it is. I hear it!”.
This leads us to the second of the objections we mentioned at
the beginning of this section, concerning the quest for the first
person authority. The debate on this issue has been particularly
lively over the last thirty years, but we will restrict ourselves to
discussing a single point: if Thompson, like Dennett, is willing
to propose a distinction of degree among levels of conscious-
ness, shouldn’t he also embrace the method of heterophenome-
nology, worked out by Dennett precisely in order to limit the
first person pretention of knowing better than anyone else what
is happening inside him? Accepting that consciousness is ar-
ticulated in a variety of levels entails, indeed, that sometimes
the subject of experience will not be able to verbally report
what he is experiencing, as also Thompson is ready to admit.
There are cases, as in Block’s example, in which the subject
succeeds in verbalizing it. But let’s suppose that the man in his
example never succeeds in realizing—nor, then, in reporting—
that there was a background noise, up to that moment implicitly
experienced. Who could demonstrate that the noise has ever
been experienced by the subject? Dennett’s heterophenome-
nological method (1991: Ch. 4, 2007) consists of giving the
greatest credit to subjects’ accounts about their experience, but
only up to the point where experimental data contradict them.
In our variation on Block’s example, while the subject could
deny having ever heard any noise, a series of elements gathered
by the scientist could contradict him, for example the fact that
the man moved away from the source of noise, in order to bet-
ter continue his conversation, or the fact that, asked about the
intimacy of the place in which he was chatting, he answered
that the place was not at all intimate. No view from within
could ever settle this matt e r.
Therefore, Thompson’s appeal to the phenomenological tra-
dition, though relevant to the goal of improving first person
descriptions11 (which represent the explanandum of a science of
consciousness), shouldn’t make us forget the various Dennet-
tian insights about the fact that “there are circumstances in
which people are just wrong about what they are doing and how
they are doing it. It is not that they lie in the experimental situa-
tion, but that they confabulate, they fill in the gaps, guess,
speculate, mistake theorizing with observing” (1991: p. 109).
As we hinted above, this doesn’t imply a complete acceptance
of Dennett’s skepticism about phenomenal aspects of con-
sciousness, which, on the contrary, seemed to us originnally
dealt with by the authors belonging to the sensorimotor front.
But the fact that Thompson renamed “pre-reflective bodily
self-consciousness” what Dennett and the majority of the neu-
roscientists usually call “consciousness” or “subjectivity ” doesn’t
really seem to add anything to the explanation of the pheno-
The sensorimotor paradigm provides some insights concern-
ing the problem of consciousness. In particular, the notion of
virtual presence and the related features of grabbiness and
bodiliness offer some suggestions aiming to restate the problem
of phenomenal consciousness so that it can be scientifically
addressed. However, the claim that the explanatory gap is
closed is strongly overstated, for at least two reasons. First, the
enactivist treatment of the issues of virtual presence and TVSS
does not seem to force us to get rid of the brain as a constituent
of the supervenience basis of perceptual experience. At most, it
shows that the supervenience basis also includes some external
factors. Second, even if one endorses the kind of externalism
involved in the so-called extended mind framework (Clark and
Chalmers’s vehicle externalism), still there is no clear evidence
that the brain plays a constitutive role, rather than a merely
causal/instrumental one, in the production of phenomenal con-
Similar considerations can be done for Thompson’s notion of
PBSC. We showed indeed that the alleged role played by PBSC
in a theory of subjectivity can, in part, be filled by the same
notion of biological selfhood that Thompson borrows from
autopoiesis theory. However, the enactivist approach has un-
doubtedly the merit of highlighting the role of bodily compe-
11Thompson, Noë and Pessoa (1999) already stressed this point about the
phenomenological shortcomings of Dennett’s (1991) description of the
filling-in phenomenon in the blind spot. Dennett admitted his descriptive
mistakes, but pointed out that nothing in these authors’ remarks refutes the
heterophen omenological method (2005: p. 163).
10This is an example that has many variations in the XX century history o
philosophy, from Husserl and Merleau-Ponty until the debate between
Dretske (1994) and Dennett (1994) about non epistemic seeing, or “about
differences that make no difference”.
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tence in perception, providing some insights to the study of
conscious experience.
Bach-y-Rita, P. (1972). Brain mechanisms in sensory substitution. New
York: Academic Press.
Ballard D. H. (1996). On the function of visual representation. In K.
Akins (Ed.), Perception (pp. 111-131). Oxford: Oxford University
Ballard, D. H. ( 1991). Animate vision. Artificial In telligence, 48, 57-86.
Block, N. (1997). On a confusion about a function of consciousness. In
N. Block, O. Flanagan, & G. Güzeldere (Eds.), The nature of con-
sciousness (pp. 375-416). Cambridge, MA: MIT Press .
Botvinick, M., & Cohen, J. D. (1998). Rubber hand “feels” what eyes
see. Nature, 391, 756.
Brooks, R. (1991). Intelligence without representation. Artificial Intel-
ligence, 47, 139-159.
Brooks, R. (1999). Cambrian intelligence. Cambridge, MA: MIT Press.
Chalmers, D. (1996). The conscious mind. Oxford: Oxford University
Churchland, P. S., & Ramachandran, V. S. (1996). Filling in: Why
Dennett is wrong. In K. Akins (Ed.), Perception (pp. 132-157). Ox-
ford: Oxford University Press.
Clark, A. (1997). Being there. Cambridge, MA: MIT Press.
Clark, A. (1999). Visual awareness and visuomotor action. Journal of
Consciousness Studies, 6, 1- 18.
Clark, A. (2008). Supersizing the mind: Embodiment, action, and cog-
nitive extension. Oxford: Oxford University Press.
Clark, A. (2009). Spreading the joy? Why the machinery of conscious-
ness is (probably) still in the head. Mind, 118, 963-993.
Clark, A., & Chalmers, D. (1998). The extended mind. Analysis, 58,
Dennett, D. C. (1969). Content and consciousness. London: Routledge
& Kegan Paul.
Dennett, D. C. (1991). Consciousness explained. Boston: Little Brown
& C.
Dennett, D. C. (1994). Get real. Phil os op hi cal Topics, 22, 505-568.
Dennett, D. C. (2005). Sweet dreams: Philosophical obstacles to a sci-
ence of consciousness. Cambridge, MA: MIT Press.
Dennett, D. C. (2007). Heterophenomenology reconsidered. Phenome-
nology and the Cognitive Sciences, 6, 247-270.
Dretske, F. (1994). Differences that make no difference. Philosophical
Topics, 22, 41-58.
Fodor, J. A. (1980). Methodological Solipsism considered as a research
strategy in cognitive science. Behavioral and Brain Sciences, 3, 63-
Gibson, J. J. (1979). The ecological approach to visual perception.
Boston: Houghton Mifflin.
Hurley, S. (1998). Consciousness in action. Cambridge: Harvard Uni-
versity Press.
Hurley, S. (2001). Perception and action: Alternative views. Synthese,
129, 3-40.
Hurley, S., & Noë, A. (2003). Neural plasticity and consciousness.
Biology and Philosophy, 18, 131-168.
Kanizsa, G. (1979). Organization in vision. New York: Praeger.
Kelso, S. A. (1995). Dyn amic patte rns . Cam bridge, MA: MIT Press.
Levine (1983). Materialism and qualia: The explanatory gap. Pacific
Philosophical Quarterly, 64, 354-361.
Lycan, W. (1987). Consciousness. Cambridge, MA: MIT Press.
Maturana, H., & Varela, F. (1987). The tree of knowledge. Boston:
McGinn, C. (1989). Mental content. Oxford: Blackwell.
Metzinger, T. (2003). Being no one. The self-model theory of subjectiv-
ity. Cambridge, MA: MIT Press.
Myin, E., & O’Regan, K. (2008). Situated perception and sensation in
vision and other modalities. In P. Robbins, & M. Aydede (Eds.),
Cambridge Handbook of Situated Cognition (pp. 185-200). Cam-
bridge: Cambridge University Press.
Noë, A. (2004). Action in Perception, Cambridge, MA: MIT Press.
Noë, A. (2006). Experience without the head. In T. S. Gendler, & J.
Hawthorne (Eds.), Perceptual experience (pp. 411-434). Oxford:
Oxford University Press.
Noë, A., & Thompson, E. (2004). Are there neural correlates of con-
sciousness? Jour nal of Consciousness Studies, 11, 3-28.
O’Regan, K., Myin, E., & Noë, A. (2005). Sensory consciousness ex-
plained (better) in terms of “corporality” and “alerting capacity”.
Phenomenology and the Cognitive Sciences, 4, 369-387.
O'Regan, K., & Noë, A. (2001). A sensorimotor account of vision and
visual consciousness. B e havior al and Brain Sciences, 24, 939-1011.
Ramachandran, V., & Blakeslee, S. (1998). Phantoms in the brain.
New York: William Morrow.
Thelen, E., & Smith, L. (1994). A dynamical systems approach to the
development of cognition and action. Cambridge, MA: MIT Press.
Thompson, E. (2005). Sensorimotor subjectivity and the enactive ap-
proach to experience. Phenomenology and the Cognitive Sciences, 4,
Thompson, E. (2007). Mind in life. Cambridge, MA: Harvard Univer-
sity Press.
Thompson, E., & Varela, F. (2001). Radical embodiment: Neural dy-
namics and consciousness . Trends in Cognitive Science s, 5, 418-425.
Thompson, E., Noë, A., & Pessoa, L. (1999). Perceptual completion. In
J. Petitot et al. (Eds.), Naturalizing phenomenology. Stanford, CA:
Stanford University Press.
Thompson, E., Palacios, A., & Varela, F. (1992). Ways of coloring:
Comparative color vision as a case study for cognitive science. Be-
havioral and Brain Sciences, 15, 1-74.
Varela, F., Thompson, E., & Rosch, E. (1991). The embodied mind:
Cognitive science and human experience. Cambridge, MA: MIT
Wilson, R. A. (2004). Boundaries of the mind. The individual in the
fragile sciences: Cognition. Cambridge, MA: Cambridge University