Content uploaded by Jean Decety
Author content
All content in this area was uploaded by Jean Decety on Feb 19, 2022
Content may be subject to copyright.
Motor cognition: a new paradigm to study self–other interactions
Philip L Jackson and Jean Decety
Accumulative empirical evidence has been reviewed in support
of the notion that the production and perception of action as well
as the interpretation of others’ actions are functionally
connected, and indeed, rely on common distributed neural
systems in the premotor and parietal cortices. We suggest that
these neural systems sustain shared representations between
self and other that are crucial in social interactions. The inferior
parietal cortex plays a special role in the sense of agency, which
is a fundamental aspect to navigate within this neural network.
The role of other brain areas that implement and regulate these
shared representations remains to be specified.
Addresses
Social Cognitive Neuroscience, Institute for Learning and Brain
Sciences, University of Washington, Box 357988, Seattle,
Washington, USA
e-mail: decety@u.washington.edu
Current Opinion in Neurobiology 2004, 14:259–263
This review comes from a themed issue on
Cognitive neuroscience
Edited by John Gabrieli and Betsy Murray
0959-4388/$ – see front matter
ß2004 Elsevier Ltd. All rights reserved.
DOI 10.1016/j.conb.2004.01.020
Abbreviations
fMRI functional magnetic resonance imaging
Introduction
Say you have lost your car keys and you are anxious as
time passes because you might miss your morning flight.
An efficient way to find them is to stop wandering around,
then retrace in your mind what you have done the
previous evening, where in your house you have been,
with whom you have interacted, and so forth. Such a
mental simulation reactivates, amongst other things, your
motor representations in working memory and hopefully
will help you to spot your keys. This everyday example
illustrates the intimate and deeply rooted link between
motor systems and cognition. The concept of ‘motor
cognition’ grasps the notion that cognition is embodied
in action, and that the motor system participates in what is
classically considered as high-level mental processing,
including those processes involved in our social interac-
tions. The fundamental unit of this paradigm is action,
defined as the movements produced to satisfy an inten-
tion towards a specific goal, or in reaction to a meaningful
event in the physical and social environments. Motor
cognition takes into account the preparation and pro-
duction of actions, as well as the processes involved in
recognizing, anticipating, predicting and interpreting the
actions of others. In this review, we draw on the most
recent evidence from several fields of research to illus-
trate the broad reach of motor cognition and its impact
on human social interactions.
Perception-action and shared
representations
The continuity between action and cognition is primarily
formed on the basis of perception and action cycles, which
are the fundamental foundation of the nervous system.
These processes are functionally intertwined: perception
is a means to action and action is a means to perception.
Indeed, the vertebrate brain has evolved for governing
motor activity with the basic function of transforming
sensory patterns into patterns of motor coordination [1].
Gibson [2] proposed the metaphor of ‘affordance’ to
account for the direct link between perception and action
in 1966. Later, Shepard [3] argued that as a result of
biological evolution and individual learning, the organism
is, at any given moment, tuned to resonate to the incom-
ing patterns that correspond to the invariants that are
significant for it. These patterns, according to Shepard,
have become deeply internalized (i.e. represented), and
even in the complete absence of external information, the
system can be excited entirely from within (while imag-
ining, for example). Today, the common coding theory
claims parity between perception and action [4]. Its core
assumption is that actions are coded in terms of the
perceivable effects (i.e. the distal perceptual events) that
they should generate [5,6]. This theory also states that
perception of an action should activate action representa-
tions to the degree that the perceived and the represented
action are similar [6]. As such, these representations may
be shared between individuals. Indeed, the meaning of a
given object, action, or social situation may be common to
several people and activate corresponding distributed
patterns of neural activation in their respective brains
[7
]. There is a growing number of behavioral and neu-
rophysiological studies that demonstrate that perception
and action have a common coding and that this leads to
shared representations between self and others.
Observation–execution matching system
The discovery of ‘mirror neurons’ provided the first
convincing physiological evidence for a direct matching
between action perception and action execution. Mirror
neurons are found in the ventral premotor cortex of the
macaque monkey, and they fire both when it carries out a
goal-directed action and when it observes the same action
performed by another individual [8]. More recently, it was
www.sciencedirect.com Current Opinion in Neurobiology 2004, 14:259–263
found that a subset of these mirror neurons also respond
when the final part of an action is hidden and can only be
inferred, however when the action is seen in its entirety
this part is crucial in triggering the response [9]. There-
fore, specific neurons in this region respond to the repre-
sentation of an action rather than to the action itself.
Ongoing work by this laboratory extends this idea by
showing that some neurons in the same region display
mirror properties between motor sense and other mod-
alities such as audition [10,11
]. This demonstrates that
single neurons are concerned with some actions regard-
less of the modality through which they are inferred, and
suggests that it is the consequence of the action that is
represented. Such neurons are not restricted to the pre-
motor cortex but have also been identified in other areas
of the brain, notably in the posterior parietal cortex in
relation to actions performed with objects [12
].
Evidence for a matching system in humans continues to
accumulate. For instance, it was found that when subjects
observe a block stacking task, the coordination between
their gaze and the actor’s hand is predictive rather than
reactive, and is highly similar to the gaze-hand coordina-
tion when they perform the task themselves [13]. These
results indicate, in accordance with the common coding
theory, that during action observation subjects implement
eye motor programs directed by motor representations of
manual actions. Consistent with this view, hemodynamic
increases have been detected in the premotor cortex, the
intraparietal cortex, the parietal operculum and inferior
frontal gyrus when subjects observe grasping movements
towards an object [14]. These regions were activated to a
higher degree during actual execution of the same task. In
another domain it has been found that speech listening is
associated with an increase of motor-evoked potentials
recorded from the listeners’tongue muscles when the
presented words strongly involve tongue movements
when uttered [15
]. Moreover, a functional magnetic
resonance imaging (fMRI) study showed a common func-
tional organization between motor recognition and lang-
uage production [16].
This matching system offers a parsimonious explanation
of how we understand the actions of others: by a direct
mapping of the visual representation of the observed
action into our motor representation of the same action
[17]. This interpretation is also compatible with the
simulation theories, which assume that when one observes
the actions of others, one covertly simulates the same
action (but see update; [18]).
From motor priming to social facilitation
One consequence of the functional equivalence of per-
ception and action is that watching an action performed
by another person facilitates the later reproduction of that
action in oneself. A series of psychophysics studies have
shown that when subjects are asked to produce gestures
on cue, the response is quicker when stimulus and
response gestures are matched than when they are incon-
gruent [19]. The response is also faster when subjects are
asked to produce the response under imitative cueing
rather than under symbolic cueing conditions (e.g. when
shown a certain color).
Castiello and co-workers [20] have also explored the
nature and specificity of motor priming by examining
behavioral responses to actions produced by a robotic arm
versus those produced by a human arm. They showed a
priming advantage for the latter. Cerebral correlates of
this effect seem to involve the right inferior parietal
lobule as demonstrated by Perani et al. [21], who reported
greater activity in this region when subjects observed
grasping movements executed by a human hand than
when the same actions were performed by a virtual hand.
Thus, perception of actions performed by real hands taps
into existing action representations, whereas similar
conditions involving virtual reality do not access the
full motor knowledge available. Subsequent work by
Castiello [22
]showed priming effects even when the
kinematics (i.e. the movement properties) of a model
were not available, and suggested that the motor inten-
tion of conspecifics can be inferred from their gaze. A
further argument in favor of the common mechanism for
observed and executed action is provided by the study of
Kilner et al. [23
]. Altogether, such findings suggest that
the observation of action can prime a similar response in
theobserver,andthatthedegreetowhichtheobserved
action facilitates a similar response depends on the
kinematics and visual similarity between the prime
and the response. These findings also cast some light
onto the phenomenon called ‘social facilitation’,which
accounts for the demonstration that the presence of other
people can affect individual performance. An elegant
series of experiments on spatial compatibility based on
reaction time by Sebanz et al. [24] demonstrated that
actions at the disposal of another agent are represented
and have impact on one’s own actions, even when the
task at hand does not require taking the actions of another
person into account.
Imitation
Imitation involves perception–action coupling but cannot
be reduced to a simple motor resonance mechanism, as
opposed to motor mimicry. It implicates executive func-
tions and the sense of agency [25], but simple imitation
may occur without conscious awareness [26]. Although it
is still controversial whether or not non-human primates
possess the ability to imitate spontaneously, imitation
occurs naturally in human infants [27]. Research shows
that young children are capable of rational imitation in the
sense that they appear to view human action in terms of
the relation between the agent, the means and the goal
(physical outcome) of the action [28
]. On the other
hand, individuals with autism have often been found to
260 Cognitive neuroscience
Current Opinion in Neurobiology 2004, 14:259–263 www.sciencedirect.com
be impaired at imitation [29]. Recently, Avikainen and
co-workers [30] showed that adults with Aspergers syn-
drome or high-functioning autism were impaired at imi-
tating in a mirror-images manner, a form of imitation that
is favored by normal adults.
A neuroimaging study [31
]found relative distinct neural
instantiation of processing the goal and the means in an
imitation paradigm. A new fMRI study demonstrated left
versus right hemispheric specificity in the premotor cor-
tex related to the object and the movements that can be
performed with the objects [32
].
There are other neuroimaging studies of imitation that
reported bilateral activation of the inferior frontal gyrus
and premotor cortex when subjects imitated finger and
hand movements [33,34]. Interestingly, the activity in
the inferior frontal gyrus was greater for goal-directed
finger movements than it was when movements had no
explicit goal. Tanaka and Inui [35] also reported similar
activation in the inferior frontal gyrus for imitation of
finger configurations, but not for imitation of hand/arm
postures. Schubotz and Von Cramon [36] proposed that
the lateral premotor cortex transforms into a somatoto-
pic representation not only during observed action but
during any kind of sequential perceptual event. The
role of the premotor cortex in such a context lies within
the representation of the ‘pragmatic features’,orthe
potential motor significance of attended sensory events
[37,38].
An fMRI study has demonstrated that imitation and
observation of emotional facial expressions activate a
similar network of brain areas [39]. Comparison of these
two actions showed that there was greater activity during
imitation in different premotor areas, the superior tem-
poral cortex, insula and amygdala. The authors proposed
that the insula is fundamental to the system that uses
action representation to understand the emotions of
others.
Whereas imitation is useful for learning new skills, the
recognition that someone is imitating us plays an impor-
tant role in communicative exchanges and in the devel-
opment of intersubjectivity [40,41]. Two neuroimaging
studies explored the extent to which being imitated and
imitating another individual rely on similar neural
mechanisms [42,43
]. When the conditions of imitation
were contrasted to the control condition in which subjects
acted differently from the experimenter, specific activa-
tion was found in the inferior parietal lobule, in addition
to a common set of cortical areas including the right
inferior frontal gyrus, the superior and medial prefrontal
cortex. The left inferior parietal lobule was activated
more when subjects imitated the other, whereas the right
homologous region was associated with being imitated
by the other.
The sense of agency and action identity
The research reviewed here strongly supports tight func-
tional coupling between actions produced by the self and
actions produced by others. This coupling is underpinned
by a distributed pattern of activation in the premotor and
parietal cortex that reliably fires in response to both an
action internally generated and the perception of the
same action produced by another person. However, in
normal circumstances there is no confusion between
actions produced by the self and actions produced by
another. Several models have been proposed to account
for the sense of agency (i.e. the sense of being the initiator
or source of a movement, action, or thought) including
forward models [44]. In fact, there is an asymmetry
between observing one’s own actions and observing
someone else’s actions. Individuals are more accurate
in recognizing their own actions than the actions per-
formed by another [6]. There is good evidence that the
inferior parietal cortex and the insula are crucial compo-
nents for the sense of agency [42,43
,45–49]. In a study
designed to investigate the brain correlates of the feeling
of being in control of an action, Farrer and co-workers
[50
]demonstrated an increase in activity in the right
inferior parietal lobule as the ‘feeling of control’over
the manipulation of a virtual hand decreased (Figure 1).
Another study found right posterior superior temporal
sulcus activation that correlated positively with the
temporal delay introduced online between the action of
Figure 1
Current Opinion in Neurobiology
R123
Conditions
4
0
–4
4
2
–2
–6
–8 C1 C2
Hemodynamic variation (% change)
(a)
(b)
Parietal cortex and the sense of agency. Right inferior parietal lobule
activation (x ¼56, y ¼56, z ¼36) superimposed into (a) coronal and (b)
sagittal sections of T1-weighted MRI. The histogram shows the relative
hemodynamic variations in the right inferior parietal lobule across the
experimental conditions. The conditions were; (1) the participant moved a
joystick while seeing the exact visual effect on a virtual hand; (2) angular
distortions were introduced into the system at various angles from 258;
(3) 508; or (4) another person moved the joystick. The experiment was
also performed in control conditions, in which participants produced
random movements (C1) whilst seeing their consequences, and (C2)
while they watched the virtual hand moving. Adapted from [50
].
Motor cognition Jackson and Decety 261
www.sciencedirect.com Current Opinion in Neurobiology 2004, 14:259–263
the hands and their visual feedback [51]. Thus, distinct
networks are involved in perceiving spatial versus temporal
features of one’s own movements. Finally, an experiment
recently demonstrated that the neurodynamic activity
starts earlier in several cortical regions involved in motor
control when participants made judgements about their
own actions versus those of others [52
]. This shows that
the dynamics of neural activation within the shared
cortical network are an important aspect to distinguish
one’s own actions from the actions of others.
Conclusions
Motor cognition arises from action/perception cycles
that can be mediated by internal representations. This
enables us not only to react to our environment but also to
anticipate the consequences of our actions. Moreover,
these representations not only guide our own behavior
but are also used to interpret the behavior of others,
because they are shared across individuals [25]. Important
questions for future research concern the respective
computational role of each brain area that subserves
shared representations between self and other, as well
as a better description of what precise aspects of an action
are actually represented. The temporal distribution of
these representations is also likely to shed some light on
the various mechanisms that fall under motor cognition.
Update
A recent fMRI experiment has shown that the motor
system is engaged when participants use arbitrary visual
cues to prepare their own actions, and also when they use
the same sues to predict the actions of other people [53
].
However, these two tasks activate separate sub-circuits
within the premotor cortex. Forming an explicit repre-
sentation of another person’s intention as an intentional
agent necessitates an additional neural/computational
mechanism (requiring the participation of the medial
prefrontal cortex), beyond the shared representation level.
References and recommended reading
Papers of particular interest, published within the annual period of
review, have been highlighted as:
of special interest
of outstanding interest
1. Sperry RW: Neurology and the mind-body problem.
Am Sci 1952, 40:291-312.
2. Gibson JJ: The Senses Considered as Perceptual Systems. Boston:
Houghton-Mifflin; 1966.
3. Shepard RN: Ecological constraints on internal representation:
resonant kinematics of perceiving, imagining, thinking, and
dreaming.Psychol Rev 1984, 91:417-447.
4. Prinz W: Perception and action planning.Eur J Cogn Psychol
1997, 9:129-154.
5. Hommel B, Mu
¨sseler J, Aschersleben G, Prinz W: The theory
of event coding; a framework for perception and action.
Behav Brain Sci 2001, 24:849-878.
6. Knoblich G, Flach R: Action identity: evidence from self-
recognition, prediction, and coordination.Conscious Cogn
2003, 12:620-632.
7.
Decety J, Sommerville JA: Shared representations between
self and others: a social cognitive neuroscience view.
Trends Cogn Sci 2003, 7:527-533.
The authors present a comprehensive up-to-date multi-disciplinary
review, which includes findings from developmental science, social
psychology, neuropsychology and cognitive neuroscience about the
development of shared representations and their functional role in inter-
personal awareness.
8. Rizzolatti G, Fadiga L, Gallese V, Fogassi L: Premotor cortex and
the recognition of motor actions.Brain Res Cogn Brain Res 1996,
3:131-141.
9. Umilta MA, Kohler E, Gallese V, Fogassi L, Fadiga L, Keysers C,
Rizzolatti G: I know what your are doing: a neurophysiological
study.Neuron 2001, 31:155-165.
10. Keysers C, Kohler E, Umilta MA, Nanetti L, Fogassi L, Gallese V:
Audiovisual mirror neurons and action recognition.Exp Brain
Res 2003, 153:628-636.
11.
Kohler E, Keysers C, Umilta MA, Fogassi L, Gallese V, Rizzolatti G:
Hearing sounds, understanding actions: action representation
in mirror neurons.Science 2002, 297:846-848.
This single-cell recording study in the monkey demonstrates that some
neurons in the premotor cortex discharge when the animal performs a
specific action and when it hears a sound related to this action. Most of
these neurons also discharge when the monkey observes the same
action, and are thus referred to as audiovisual mirror neurons.
12.
Gallese V, Fogassi L, Fadiga L, Rizzolatti G: Action representation
and the inferior parietal lobule.InAttention and Performance,
vol 19. Edited by Prinz W, Hommel B. New York: Oxford University
Press; 2002:247-266.
The authors present the first electrophysiological evidence of mirror
neurons in the monkey posterior parietal cortex.
13. Flanagan JR, Johansson RS: Actions plans used in action
observation.Nature 2003, 424:769-771.
14. Gre
`zes J, Armony JL, Rowe J, Passingham RE: Activations
related to ‘mirror’and ‘canonical’neurones in the human brain:
an fMRI study.Neuroimage 2003, 18:928-937.
15.
Fadiga L, Craighero L, Buccino G, Rizzolatti G: Speech listening
specifically modulates the excitability of tongue muscles: a
TMS study.Eur J Neurosci 2002, 15:399-402.
This transcranial magnetic stimulation study shows that during speech
listening there is an increase of motor-evoked potentials from the listen-
ers’tongue muscles to perceived words that involve important tongue
movements when uttered. These data suggest that speech motor areas
are activated by word listening according to phoneme-specific rules.
16. Hamzei F, Rijntjes M, Dettmers C, Glauche V, Weiller C, Buchel C:
The human action recognition system and its relationship to
Broca’s area: an fMRI study.Neuroimage 2003, 19:637-644.
17. Rizzolatti G, Fogassi L, Gallese V: Neurophysiological
mechanisms underlying the understanding and imitation of
action.Nat Rev Neurosci 2001, 2:661-670.
18. Dokic J, Proust J: Simulation and Knowledge of Action. Edited by
Dokic and Proust. Philadelphia: Benjamins Publishers; 2002.
19. Sturmer B, Ascherleben G, Prinz W: Correspondence effects
with manual gestures and postures: a study of imitation.
J Exp Psychol Hum Percept Perform 2000, 26:1746-1759.
20. Castiello U, Lusher D, Mari M, Edwards M, Humphreys GW:
Observing a human or a robotic hand grasping an object:
differential motor priming effects.InCommon Mechanisms in
Perception and Action. Edited by Prinz W, Hommel B. New York:
Oxford University Press; 2002:315-333.
21. Perani D, Fazio F, Borghese NA, Tettamanti M, Ferrari S, Decety J,
Gilardi MC: Different brain correlates for watching real and
virtual hand actions.Neuroimage 2001, 14:749-758.
22.
Castiello U: Understanding others’ people actions: intention
and attention.J Exp Psychol Hum Percept Perform 2003,
29:416-430.
The findings from this multiple-experiment study show how the observa-
tion of an action performed by a human actor or a robotic arm may prime
the performance of someone about to execute a similar action. Most
fascinating were the results supporting the notion that motor intentions
can be inferred solely by monitoring the gaze of an individual.
262 Cognitive neuroscience
Current Opinion in Neurobiology 2004, 14:259–263 www.sciencedirect.com
23.
Kilner JM, Paulignan Y, Blakemore SJ: An interference effect
of observed biological movement on action.Curr Biol 2003,
13:522-525.
In this study, participants executed arm movements while observing either
a robot or another human producing the same or qualitatively different arm
movements. The results show that observing another human make
incongruent movements interferes with movement execution but observ-
ing a robotic arm making incongruent movements does not.
24. Sebanz N, Knoblich G, Prinz W: Representing others’actions:
just like one’s own? Cognition 2003, 88:B11-B21.
25. Decety J, Chaminade T: When the self represents the other:
a new cognitive neuroscience view of psychological
identification.Conscious Cogn in press.
26. Tessari A, Rumiati RI, Haggard P: Imitation without awareness.
Neuroreport 2002, 13:2531-2535.
27. Meltzoff AN, Decety J: What imitation tells us about social
cognition: a rapprochement between developmental
psychology and cognitive neuroscience.Philos Trans R Soc
Lond B Biol Sci 2003, 358:491-500.
28.
Gergely G, Bekkering H, Kiraly I: Rational imitation in preverbal
infants.Nature 2002, 415:755.
In this ingenious study, 14-month-old infants were shown an event in
which a human actor activated a tap light using her head. If the reason that
the actor failed to use her hands to activate the light was clear (e.g. she
was holding a blanket around her body) toddlers imitated only the goal of
the event (i.e. turned on the light with their hand). However, if it was not
apparent why the actor used her head instead of her hand to activate the
light, toddlers reenacted both the means and the goal (i.e. they used their
head to activate the light).
29. Rogers SJ: An examination of the imitation deficit in autism.
In Imitation in Infancy. Edited by NJ Butterworth G. Cambridge:
Cambridge University Press; 2001:254-283.
30. Avikainen S, Wohlschlager A, Liuhanen S, Hanninen R, Hari R:
Impaired mirror-image imitation in Asperger and high-
functioning autistic subjects.Curr Biol 2003, 13:339-341.
31.
Chaminade T, Meltzoff AN, Decety J: Does the end justify the
means? A PET exploration of imitation.Neuroimage 2002,
15:318-328.
In this study, subjects observed an experimenter building block con-
structions, and they were asked to imitate one of: a) the whole action
performed by the experimenter (means and goal), b) the goal only (end-
state of the object manipulation), or c) the means only (the motor program
used). Partially overlapping clusters of activation were found in the right
dorsolateral prefrontal cortex and in the cerebellum when subjects
imitated either the goal or the means suggesting that these regions
are involved in processing both aspects of the action. Moreover, specific
activity was detected in the medial prefrontal cortex during the imitation of
the means, whereas imitating the goal was associated with increased
activity in the left premotor cortex.
32.
Manthey S, Schubotz RI, von Cramon Y: Premotor cortex in
observing erroneous action: an fMRI study.Brain Res Cogn
Brain Res 2003, 15:296-307.
This study investigated the neural response in subjects while they payed
attention to various goal-directed hand actions, which were either correct
or erroneous with regards to employed objects or to be performed
movements. Left premotor areas were more involved in the analysis of
objects, whereas right premotor areas were dominant in the analysis of
movements.
33. Koski L, Wohlschlager A, Bekkering H, Woods RP, Dubeau MC,
Mazziotta JC, Iacoboni M: Modulation of motor and premotor
activity during imitation of target-directed actions.
Cereb Cortex 2002, 12:847-855.
34. Koski L, Iacoboni M, Dubeau MC, Woods RP, Mazziotta JC:
Modulation of cortical activity during different imitative
behaviors.J Neurophysiol 2003, 89:460-471.
35. Tanaka S, Inui T: Cortical involvement for action imitation of
hand/arm postures versus finger configurations: an fMRI
study.Neuroreport 2002, 13:1599-1602.
36. Schubotz RI, von Cramon DY: Predicting perceptual events
activates corresponding motor schemes in lateral premotor
cortex: an fMRI study.Neuroimage 2002, 15:787-796.
37. Fadiga L, Fogassi L, Gallese V, Rizzolatti G: Visuomotor neurons:
ambiguity of the discharge or ‘motor’perception?
Int J Psychophysiol 2000, 35:165-177.
38. Schubotz RI, von Cramon DY: Functional-anatomical concepts
of human premotor cortex: evidence from fMRI and PET
studies.Neuroimage 2003, 20(Suppl 1):S120-S131.
39. Carr L, Iacoboni M, Dubeau MC, Mazziotta JC, Lenzi GL: Neural
mechanisms of empathy in humans: a relay from neural
systems for imitation to limbic areas.Proc Natl Acad Sci U S A
2003, 100:5497-5502.
40. Hobson P: The Cradle of Thought. London: Macmillan 2002.
41. Trevarthen C, Aitken KJ: Infant intersubjectivity: research,
theory, and clinical applications.J Child Psychol Psychiatry 2001,
42:3-48.
42. Decety J, Chaminade T, Grezes J, Meltzoff AN: A PET exploration
of the neural mechanisms involved in reciprocal imitation.
Neuroimage 2002, 15:265-272.
43.
Chaminade T, Decety J: Leader or follower? Involvement of
the inferior parietal lobule in agency.Neuroreport 2002,
13:1975-1978.
The main finding of this neuroimaging experiment is that distinct pre-
frontal and inferior parietal areas are involved when, respectively, sub-
jects guide the actions of another individual, and when their actions are
led by someone.
44. Blakemore SJ, Wolpert DM, Frith CD: Abnormalities in the
awareness of action.Trends Cogn Sci 2002, 6:237-242.
45. Blanke O, Ortigue S, Landis T, Seeck M: Stimulating illusory
own-body perceptions. The part of the brain that can induce
out-of-body experiences has been located.Nature 2002,
419:269-270.
46. Daprati E, Sirigu A, Pradat-Diehl P, Franck N, Jeannerod M:
Recognition of self-produced movement in a case of severe
neglect.Neurocase 2000, 6:477-486.
47. Farrer C, Frith CD: Experiencing oneself vs. another person as
being the cause of an action: the neural correlates of the
experience of agency.Neuroimage 2002, 15:596-603.
48. Ruby P, Decety J: Effect of subjective perspective taking during
simulation of action: a PET investigation of agency.
Nat Neurosci 2001, 4:546-550.
49. Ruby P, Decety J: What you believe versus what you think they
believe: a neuroimaging study of conceptual perspective-
taking.Eur J Neurosci 2003, 17:2475-2480.
50.
Farrer C, Franck N, Georgieff N, Frith CD, Decety J, Jeannerod M:
Modulating the experience of agency: a positron emission
tomography study.Neuroimage 2003, 18:324-333.
This study shows that activity within the inferior part of the parietal lobe,
specifically on the right side, was inversely proportional to the feeling of
control subject felt during the production of movements with a virtual
hand. Also, the reverse covariation is observed within the insula.
51. Leube DT, Knoblich G, Erb M, Grodd W, Bartels M, Kircher TTJ:
The neural correlates of perceiving one’s own movements.
Neuroimage 2003, 20:2084-2090.
52.
Gre
`zes J, Frith CD, Passingham RE: Infering false beliefs from
the actions of oneself and others: an fMRI study.Neuroimage
in press [DOI: 10.1016/S1053-8119(03)00665-7].
In this study, subjects were presented with videoclips of themselves and
of others lifting boxes of different weights. They were asked to decide
whether the actor had a correct or false expectation of the weight. Action
related structures in the frontal and parietal cortices were found to be
activated, and the activity started earlier when subjects made judge-
ments about their own actions as opposed to actions performed by
others.
53.
Ramnani N, Miall R: A system in the human brain for predicting
the actions of others? Nat Neurosci 2004, 7:85-90.
Using fMRI, the authors tested whether the neural processes involved in
preparing one’s own actions are also used for predicting the future
actions of others. They found that areas within the action control system
are activated when predicting others’actions, but a different action sub-
system is activated when preparing one’s own actions.
Motor cognition Jackson and Decety 263
www.sciencedirect.com Current Opinion in Neurobiology 2004, 14:259–263
