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Can 18-Month-Olds Revise Attributed Beliefs?

Ildikó Király1,2

, Katalin Oláh1, and Ágnes M. Kovács2

1MTA-ELTE Social Minds Research Group, Psychology Institute, Eötvös Loránd University, Budapest, Hungary
2Department of Cognitive Science, Central European University, Budapest, Hungary

Mots clés: theory of mind, episodic memory, prospective and retrospective processes in
mindreading, memory development

un accès ouvert

journal

ABSTRAIT

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Successful social interactions rely on flexibly tracking and revising others’ beliefs. These can
be revised prospectively, new events leading to new beliefs, or retrospectively, when realizing
that an attribution may have been incorrect. Cependant, whether infants are capable of such
belief revisions is an open question. We tested whether 18-month-olds can revise an attributed
FB into a TB when they learn that a person may have witnessed an event that they initially
thought she could not see. Infants first observed Experimenter 1 (E1) hiding two objects into
two boxes. Then E1 left the room, and the locations of the objects were swapped. Infants then
accompanied Experimenter 2 (E2) to the adjacent room. In the FB-revised-to-TB condition,
infants observed E1 peeking into the experimental room through a one-way mirror, alors que
in the FB-stays-FB condition, they observed E1 reading a book. After returning to the
experimental room E1 requested an object by pointing to one of the boxes. In the FB-stays-FB
condition, most infants chose the non-referred box, congruently with the agent’s FB. Cependant,
in the FB-revised-to-TB condition, most infants chose the other, referred box. Ainsi, 18-month-
olds revised an already attributed FB after receiving evidence that this attribution might have
been wrong.

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INTRODUCTION

In everyday life, humans continuously engage in social interactions, they communicate, coor-
dinate, collaborate or even compete with each other. These activities require tracking others’
mental states adequately (Byom & Mutlu, 2013; Boyd & Richerson, 1996) in situations where
the environment is constantly changing, and one’s own beliefs, as well as those attributed to
others, have to be frequently updated. Ainsi, the mindreading system must be highly effective
and dynamically adaptive to the needs of such a dense social milieu, raising the question of
how and when flexible mindreading is achieved in ontogeny. Here we aim to investigate
whether already infants can revise an already ascribed belief in the face of new and relevant
information.

Beliefs can be attributed to others in at least two different ways: prospectively, and retro-
spectively (Király et al., 2018). Prospective belief tracking refers to the processes via which an
observer tracks what another person can and cannot witness of the unfolding events and uses
this as a basis to infer which representations the other may form. Dans de tels cas, as soon as there
is a change in the situation, which should bring about a belief change in the observed agent,
the observer performs the adequate inferences and updates in a prospective manner, depuis

Citation: Király, JE., Oláh, K., & Kovács,
Á. M.. (2023). Can 18-Month-Olds Revise
Attributed Beliefs? Open Mind:
Discoveries in Cognitive Science,
7, 435–444. https://est ce que je.org/10.1162
/opmi_a_00087

EST CE QUE JE:
https://doi.org/10.1162/opmi_a_00087

Supplemental Materials:
https://doi.org/10.1162/opmi_a_00087

Reçu: 24 Février 2023
Accepté: 29 May 2023

Intérêts concurrents: The authors
declare no conflict of interests.

Auteur correspondant:
Ildikó Király
kiraly.ildiko@ppk.elte.hu

droits d'auteur: © 2023
Massachusetts Institute of Technology
Publié sous Creative Commons
Attribution 4.0 International
(CC PAR 4.0) Licence

La presse du MIT

Can 18-Month-Olds Revise Attributed Beliefs?

Király, Oláh, and Kovács

infancy onwards (Ganea & Harris, 2010; Kovács, 2016; Song et al., 2008; Schulze &
Buttelmann, 2022; Tauzin & Gergely, 2018). Par exemple, in the classical Sally Anne task,
after attributing a false belief to Sally (par exemple., that the marble is in the basket), if she later happens
to look into the box and sees her marble there, she must update her belief. Based on the
directly available evidence that has a causal role in forming a new belief (seeing leads to
knowing), the observer will attribute a new belief to Sally.

Inversement, retrospective processes are recruited when, based on some new information, it
becomes likely that a specific belief might have been incorrectly attributed, et par conséquent,
it must be revised, (similarly to how the backtrack re-evaluation of causal relations takes place,
Gerstenberg et al., 2013, or how we modify our earlier inferences in other domains). As an
example of how we re-evaluate our own beliefs based on retrieving earlier events, imagine
you are a fire safety representative and one day the fire alarm goes on. You first arrive to
the conclusion that all present colleagues know about it and have safely left the building.
Cependant, afterwards you realize that someone could have been working in the soundproof
booth at the time of the alarm. To decide whether there may be such a person, you will rely
on your memory and try to recall all the people you met on the way out, to figure out whether
someone is missing.

En fait, retrospective, memory-based processes require the observer to recall and take into
account information not previously considered, and use the novel piece of information for
modifying one’s own description and inference of the original situation (Klein et al., 2009).

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A study by Király et al. (2018) aimed to disentangle the contribution of prospective and
retrospective processes in the belief attribution of children. Dans cette étude, after hiding two
objects into two boxes, the experimenter put on a pair of sunglasses, and the locations of
the objects were swapped by another person. Alors, the experimenter left, and participants
could explore her sunglasses, which turned out to be either opaque or transparent. In the test,
the experimenter returned, pointed to one of the boxes and asked for an object. After learning
that the sunglasses were opaque, children could retrospectively revise the experimenter’s
belief from ‘true’ to ‘false’ and (concernant)-compute its content concerning the location of the objects.
In the condition where the sunglasses were transparent, retrospective revision was not neces-
sary. The results suggested that 36-month-olds, but not 18-month-olds, responded differently in
the two conditions, only the older age group showing evidence for retrospectively attributing a
false belief (Király et al., 2018).

Cependant, such attributions could happen either by (je) revising an already (prospectively)
attributed TB into a FB, or by (ii) computing the FB of the experimenter triggered by the novel
piece of information fully retrospectively, without having computed a true belief earlier. Impor-
tantly, these two alternatives are different not only in the involved processes, but invite differ-
ent explanations for why 18-month-olds might have failed in this task.

En particulier, according to the first alternative (je), that relies on revising a prospectively
attributed belief, young children may mainly use the prospective route for attributing beliefs
to others, and retrospective revisions may pose a challenge. Ainsi, a belief is attributed as the
events unfold (par exemple., the agent seems to have visual access to the location swap), and it is main-
tained to serve future predictions or interactions (par exemple., to interpret the protagonist’s requests for
an object). The prospective route involves belief ascriptions that are based on the access of the
protagonist to specific information (what the protagonist is aware of ). Par conséquent, retrospec-
tive update processes should operate on these already attributed beliefs. When the observer
realizes that the sunglasses worn by the protagonist were opaque (and remembers that she
wore those sunglasses at the moment of the swap), a retrospective revision of her belief is

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Can 18-Month-Olds Revise Attributed Beliefs?

Király, Oláh, and Kovács

initiated. The prospectively attributed, but unwarranted true belief is identified (‘she believes
object A is in the box on the left’) and discarded, and by the retrieval of the original episode
(the event she could last see) the new belief is computed (‘she believes object A is in the box
on the right’), via retrospective revision.

Alternativement, one may argue for the second alternative (ii) that such situations do not trigger
retrospective revisions but retrospective attributions, in case true beliefs were not computed in
the task. One could argue that we attribute beliefs to others only when a perspective diver-
gence is detected. Par exemple, in the Sally Anne task, when Sally leaves the scene and the
object’s location changes, this event triggers not only an update of one’s own belief about the
state-of-affairs, but one may ascribe a divergent belief to Sally at this point based on what she
has witnessed earlier. Surtout, an initial true belief ascription is not necessary in this pro-
cess. When there is no divergence, one may simply tag one’s own representation as shared
with another person (see Martin & Santos, 2016), or encode this congruency as part of com-
mon knowledge. Ainsi, if no belief was ascribed, no belief can be revised, but specific events
may nevertheless trigger retrospective attributions. In the task of Király et al. (2018) when chil-
dren learned that the sunglasses were opaque, this could have induced a search in memory
regarding how this information could alter the agent’s perception of the events (c'est à dire. not seeing
the location change) and consequently her beliefs.

In light of these two alternatives, 18-month-olds might have failed the task of Király et al.
(2018) either because they could not revise an already attributed true belief (failure of retro-
spective belief revision), or because of difficulties in computing a belief retrospectively upon
receiving new, belief-relevant information (failure of retrospective belief attribution), if true
beliefs were not computed earlier. Ainsi, it is still unclear whether 18-month-olds can revise
already attributed beliefs at all, as the earlier used tasks may not necessarily mandate the attri-
bution of true beliefs (see recent debates in Phillips et al., 2021 and related commentaries,
Kampis & Csibra and Dudley & Kovács, 2021).

To directly address this question, we target scenarios where relying on common knowledge
is not sufficient, and infants have to first attribute beliefs to others (c'est à dire. when attributing diver-
gent or false beliefs), in order to investigate whether they can later flexibly revise these. Evi-
dence from different tasks seems to suggest that by 18 mois, infants are able to attribute false
beliefs via monitoring the perceptual access of the protagonist (Kovacs et al., 2010; Senju,
Southgate, Snape, Leonard & Csibra, 2011; Knudsen & Liszkowski, 2012; Scott & Baillargeon,
2017; Southgate et al., 2010; Király et al., 2018; but see also replication problems in Schuwerk
et coll., 2018; and Crivello & Poulin-Dubois, 2018).

In the present task, successful performance would necessarily require updating an attrib-
uted belief: infants will need to revise an already attributed false belief upon learning that
the agent could have witnessed a situation that they initially thought had not been perceived
by her. While 3-year-olds can retrospectively update attributed beliefs in such tasks (Király
et coll., 2018, Exp. 3), the question of whether 18-month-olds can revise their attributed false
beliefs was not directly tested before.

In the current study, 18-month-olds first observe two novel objects hidden by Experimenter
1 (E1) into two boxes. Then E1 leaves the room, and the locations of the objects are swapped.
Infants are then asked to accompany Experimenter 2 (E2) to the neighboring room to call E1
back. When they enter the room, infants in the FB-revised-to-TB condition, observe E1 peeking
into the experimental room through a one-way mirror. In in the FB-stays-FB condition, E2 is
reading a book and the one-way mirror is covered. In a third condition (FB condition), infants
do not leave the experimental room and receive no extra information. After returning to the

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Can 18-Month-Olds Revise Attributed Beliefs?

Király, Oláh, and Kovács

room, E1 requests an object by pointing to one of the two boxes. In line with previous studies
(Southgate et al., 2010; Király et al., 2018), we expect infants to interpret the gesture as refer-
ring to the object which the experimenter believes to be inside, thus this referent mapping is
dependent on the attributed belief. If infants attribute false beliefs, they should choose the non-
referred box, given that the experimenter was not present when the location of the objects was
swapped. En outre, if they can revise a false belief into a true belief after seeing E1 peeking
through a one-way mirror, they are expected to choose the referred box.

MÉTHODES

Participants

Sixty 18-month-old infants were recruited (20 per condition). 12 children were excluded
because of experimenter error (2 per condition) or quitting the experiment before the test
phase (FB:2; FB-revised-to-TB:1; FB-stays-FB:1), or choosing both objects during the test phase
(FB-revised-to-TB: 2). The final sample was 15 infants in the FB-revised-to-TB condition; 16
infants in the FB condition, et 17 infants in the FB-stays-FB condition (âge moyen = 18.12
mois, range: 17.5-18.5 month).

Procedure

The procedure and sample size selection were based on Király et al. (2018) Experiment 3.
Warm up trials preceded the testing phase (see details in supplemental materials, https://osf
.io/7jvpf) and test trials had three phases.

Belief Induction Phase. E1 first gave the infants the two novel objects to explore for about 10
seconds. These objects were not labelled in this phase. E1 then placed an object in each box
and closed the lids. The location of the objects was counterbalanced across infants. At this
indiquer, Experimenter 2 (E2) asked E1 to go out for a while. After E1 left, E2 deceptively
approached the boxes, switched the objects, and closed the boxes. This phase was identical
for all three conditions.

In the FB condition, replicating Southgate et al. (2010), infants stayed in
Belief Revision Phase.
the room, while E2 went to call back E1 alone. In the FB-revised-to-TB and FB-stays-FB con-
ditions all infants accompanied E2 to the adjacent room to call E1 back. In FB-revised-to-TB
condition, when they entered the adjacent room, infants saw E1 peeking into the experimental
room through a one-way mirror. Despite the arrival of E2 and the child, the experimenter con-
tinued looking through the one-way mirror and did not interact with them. E2 encouraged the
child to look through the one-way mirror (all children looked through it). Note that during all
this time, the objects were not visible (were in the closed boxes). In the FB-stays-FB condition,
when they entered the adjacent room, infants saw E1 sitting on a chair and reading a book,
while the one-way mirror was covered with a curtain. Here too, despite E2 and the child being
là, the experimenter continued reading and did not interact with them. After being away
environ 45 seconds, E2 asked E1 and the child to return to the experimental room in
both conditions, without any further interaction.

Test-phase. After returning E1 greeted the infant, and sat behind the two boxes. E1 then
pointed at one of the boxes (counterbalanced across infants) and said (in Hungarian), “Do
you remember what I put here? I put a sefo here. Shall we play with the sefo?», alternating
gaze between the infant and the referred box twice. E1 then grasped both boxes, extended
her arms towards the child and simultaneously opened the lids of both boxes that were

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Can 18-Month-Olds Revise Attributed Beliefs?

Király, Oláh, and Kovács

oriented towards the child. À ce point, the contents of the boxes became visible only to
the child. E1 then said, “Can you give me the sefo?», while looking directly at the child,
and not looking towards either box. E1 repeated the question until the child began to
approach one of the boxes, pointed towards one of the boxes, or until 180 seconds had
passed (voir la figure 1).

Coding

The sessions were video-recorded and coded off-line. The dependent measure was the choice
that children made in response to E1’s request. The first response towards one of the boxes,
after E1 had said, ‘Can you give me the sefo?’ was coded as the child’s choice and was cat-
egorized as choosing the referred or the non-referred box. Both reaching and pointing
responses were accepted as valid choices. All sessions were coded also by a second observer,
blind to the experimental condition. Interrater agreement was 97% (Cohen’s Kappa: 0.933).

RÉSULTATS

In the FB condition 14 participants (87,5%) chose the non-referred box and 2 (12,5%) chose
the referred one. In the FB-stays-FB condition which includes an intervention phase with no
belief relevant elements, 15 infants (88,24%) chose the non-referred box, et 2 (11,76%) le
referred one. Cependant, importantly, in the FB-revised-to-TB condition, in which children wit-
nessed E1 peeking through the one-way mirror, infants showed the expected opposite pattern,
13 infants (86,66 %) chose the referred box, and only 2 of them (13,33%) chose the non-
referred one (voir la figure 2, data is available at: https://osf.io/c9zs5.

UN 2 × 3 chi-square test revealed a difference in the pattern of choices between the three
conditions (chi-square = 25,1, df = 2, p = .00001). Fisher’s exact tests confirmed that the num-
ber of infants choosing the referred box differed significantly between the FB-revised-to-TB and
FB-stays-FB conditions (p = .00003; OR: 48.75), and also between the FB-revised-to-TB and
FB conditions (p = .00005, OR: 45.5), while FB and FB-stays-FB conditions did not differ from
l'un l'autre.

Results in the FB condition replicated the results of Southgate et al. (2010) as infants chose
the non-referred box above chance level (binomial test, p = .0018). Regarding the FB-stays-FB
condition, a binomial test similarly yielded that infants chose the non-referred box above
chance level (p = .001) providing yet a further conceptual replication that infants take into
account the experimenter’s false belief when disambiguating the referent in the two condi-
tion. Surtout, in the FB-revised-to-TB condition, infants chose the referred box signifi-
cantly above chance level (p = .003), providing clear evidence for retrospective belief revision
at such an early age.

DISCUSSION

False Belief Attribution and Retrospective Revision in 18-Month-Olds

Across three conditions, we found that infants as young as 18 months can not only track
others’ false beliefs to identify the correct referent in a communicative context, mais quand
new information comes in that warrants retrospective belief revision, they can also flexibly
update these attributed beliefs.

Flexibly monitoring the mental states of communicative partners is essential for successful
and rapid information exchange in social interactions (Sperber & Wilson, 2002). This could be
established by prospective belief attributions based on fast mapping information the

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Can 18-Month-Olds Revise Attributed Beliefs?

Király, Oláh, and Kovács

Chiffre 1. The schema of the experimental design. je. Belief induction phase: E1 puts two objects into two different boxes. After this, in her
absence, E2 swaps their locations. II. Intervention phase: children accompany E2 to call E1 back to the room, and children find E1 in the other
room a) looking through the one way mirror (FB revised to TB condition); b) reading a book (FB stays FB condition). In the third condition c)
children stay in the room and wait till E1 returns (FB-No intervention). III. Test phase: E1 points to a box and labels one object, then asks for that
object via naming it while holding both boxes towards the child.

interaction partner has direct access to, or via retrospective attributions relying on revising an
already maintained belief in light of indirect evidence.

While previous studies suggested that 18-mo-olds can use the prospectively attributed
belief content of a communicator for referent disambiguation (Southgate et al., 2010; Knudsen
& Liszkowski, 2012), and served as evidence for the early use of belief ascription in social
interactions, the robustness and replicability of these results is disputed (see Grosse Wiesmann
et coll., 2017; Dörrenberg et al., 2018 for non-replication and Király et al., 2018 for replication).
The FB condition of the present experiment successfully replicated the results of Southgate
et autres. (2010) (direct replication) and serves as a conceptual replication of the FB-FB condition
of Király et al. (2018). En outre, data from the current FB-stays-FB condition also counts as
an additional conceptual replication of these experiments. These together support the proposal
that 18-month-olds prospectively attribute false beliefs to communicative partners.

Surtout, results from the crucial condition of the current study, the FB-revised-to-TB
condition, suggest that 18-month-olds could retrospectively revise an already attributed belief.
They revised a false belief into a true belief in a situation in which they first assumed that the
communicator had no perceptual access to the critical events, as she was not present, Et ainsi
first attributed a false belief. Surtout, upon encountering new information that warranted
belief revision (realizing that E1 could see the events through the window from the other
room), children inferred that, although she was not present in the room, she did have percep-
tual access to the critical events and successfully revised her earlier computed belief. A recent
study of Liszkai-Peres et al. (2021) found an analogous pattern of mnemonic competence in 2-
year-old children: they appropriately recalled playful goal directed actions (par exemple., reaching for
an object with a long wooden spoon) after a week delay, and they were also able to revise
their strategies of goal attainment in a changed context. En particulier, they computed the rel-
evance of the tool use given specific environmental constraints (when the objects were far),
and switched to a simpler solution when it became clear that it was no longer relevant (quand

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Can 18-Month-Olds Revise Attributed Beliefs?

Király, Oláh, and Kovács

Chiffre 2. The proportion of 18-month-old infants choosing the non-referred box (as opposed to
the referred one) in the three conditions with 95% bootstrapped confidence intervals.

objects were close). These updating processes likely rely on infants’ developing working mem-
ory capacities, which seem reliable already in the second year of life (Cheng et al., 2019),
allowing infants to retrieve multi-step (3 component) event sequences for complex planning
(Blankenship & Kibbe, 2022).

Potential Mechanisms Supporting Belief Revision

While retrospective belief revision is rather impressive at such a young age, it is still an open
question which mechanisms may support this process. At minimum, belief revision should (je)
necessarily operate on actively maintained belief contents, et (ii) relate new information to
already encoded contents. These seem mandatory in triggering the process of revision, namely
that one should recognize whether the observed novel information (c'est à dire., that the other person
could peek into the room) is relevant for the attributed belief and if so, a revision should be
appliqué.

Critique, as mentioned earlier, retrospective revisions should necessarily operate on a spe-
cific belief content in the light of new evidence (je + ii). This requires forming a link between
two belief-relevant events–that the protagonist did not see the location change and that it was
later discovered she could see through the one-way mirror – as there can be no revision with-
out making a connection to a past event. Ainsi, we conjecture that to allow for retrospective
revisions, attributed belief representations should include some information about their ori-
gins, specifically about what serves as a basis for forming the belief in the first place. In the
current task, one could initially encode that the agent did not see the location change, lequel
results in a specific belief, based on what she has seen earlier. Ainsi, when later belief-relevant
information is encountered (one learns that the protagonist could see through the one-way
mirror), this will be in conflict with the premise based on which the false belief was attributed
(‘not seeing event B, therefore believing A’). If this premise is stored together with the belief
content and marked as invalid, this should render the belief unjustified, triggering the need for
a revision. Ainsi, a successful precondition for retrospective revision is identifying that a belief
is unjustified and discarding it.

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Can 18-Month-Olds Revise Attributed Beliefs?

Király, Oláh, and Kovács

Cependant, to be able to respond flexibly to a given situation, besides discarding the initial
belief content, one should be able to revise the attributed belief with new, justified content.
Finding the adequate new belief content that replaces the old one could be realized via
recruiting at least two different kinds of mechanisms.

According to the first possibility, termed here ‘Retrospective revision via reverting to com-
mon knowledge’, after the revision process has started, and the initial belief has been identified
as unwarranted and is discarded, the new belief content is defined via substituting the old one
with the observer’s own knowledge. Par exemple, realizing that the partner could have seen
everything that the observer has seen recently, could result in the recognition that the model
has the same knowledge about reality. Donc, the related first person representation –
about the actual location of the objects – is selected.

According to a second possibility, termed here ‘Retrospective revision via (true) belief com-
putation’, after the initial belief was identified and discarded, the new belief content is defined
by computing and attributing a new (true) belief. Based on the updated visual access of the
interlocutor regarding the past event, one computes that they have a true belief about the loca-
tion of the objects.

One might wonder how to adjudicate between these possibilities, given the challenges of
distinguishing between the attribution of knowledge and/or true beliefs (Phillips et al., 2021).
Based on parsimony arguments, one might suggest that the mechanisms recruited by the first
alternative may seem simpler in terms of their representational requirements, as there is no
need to recollect the original episode to compute the belief content of the partner. Plutôt,
encoding the information monitored in the situation (first person knowledge) as shared may
be enough for the success of revision. In contrast, the second alternative would hypothesize
that in order to identify the actual true belief in the situation, the emerging task for infants
would be to compute a new belief retrospectively, which would necessitate relying on episodic
memory processes. Ainsi, in terms of the contribution of memory processes, while both alter-
natives require the tracking of the sources of (false) beliefs, the second alternative – which is an
actual retrospective attribution process – requires the accurate use of episodic memory capac-
ities as well (Mahr & Csibra, 2018) to retrieve what event details might be relevant given the
updated perceptual access information. In either case, independent from what mechanisms
are recruited to fill in the new belief content, the results suggest that infants are able to monitor
the validity of already attributed beliefs, and discard them appropriately and replace them with
a new content.

In light of the present findings, one might argue that the failure of 18-month-olds in the
study of Király et al. (2018) could have been due to the difficulties in ascribing a belief
retrospectively, given that infants likely did not attribute a true belief that could be later
revised, and not due to the lack of the ability to revise itself, as the present study provides
evidence for flexible belief revision. En effet, there is no reason to suppose that the revision
of a false belief would be easier in the present task than that of a true belief in Király et al.
(2018). This capacity constraint may be similar to that of found by Liszkai-Peres et al.
(2021) in a different domain regarding the re-computation of the relevance of tool-use in
a novel context. Two-year-old children could recall the tool use when it was first relevant
and remained relevant, and even revised its relevance when it turned irrelevant in the
novel context. Cependant, they did not recall the tool use when it was originally irrelevant,
but it turned to be relevant in the novel context, suggesting that given that relevance was
not computed earlier, they could not revise it and a retrospective re-assignment of rele-
vance did not take place.

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Can 18-Month-Olds Revise Attributed Beliefs?

Király, Oláh, and Kovács

One might wonder whether there are alternative accounts that might explain our findings.
One could propose that infants, after inferring that the protagonist could have seen everything,
became confused, et par conséquent, abandon any attribution. According to this explanation,
infants would decide to follow the pointing gesture with fidelity because they are uncertain
about what E1 might believe. Cependant, please note that this ‘confusion’ was triggered by a
very specific event, which resulted in discarding an earlier attributed false belief just as
described above, recruiting revision mechanisms that necessarily operate on a specific belief
content in light of new evidence. Surtout, this possible ‘confusion’ was specific to the con-
dition where the model was peeking into the room, and not the result of an intervening event
in general – i.e. going to the adjacent room. The necessary implication is then that the disrup-
tion was caused by the interpretation of the observed event, namely, inferring that the model
might have seen everything, and that the earlier computed false belief must be discarded.
Ainsi, even this alternative account in which infants may be uncertain whether the experi-
menter could see the events, seems to support infants’ capacity for (je) attributing a false belief
et (ii) realizing when it is adequate to discard it.

In sum, the current findings suggest that infants engage in complex retrospective belief revi-
sion processes, that entail attribution, maintenance and even some justification of beliefs, et
if found to be unjustified, their discarding. Future research should uncover whether this basic
tracking of the sources and the justification of beliefs, specifically the (lack of ) perceptual
access of the partner, could be seen as the prerequisite of source memory (Kampis et al.,
2018). The present data support the view that early belief attribution is flexible, and retrospec-
tive belief revision operates early on, which opens up the possibility for social coordination
based on context sensitive and quick inferences about others’ mental states.

REMERCIEMENTS

This study was supported by the Momentum Program of the Hungarian Academy of Sciences
to I. Király (LP-2017-17/2017). Partial funding came from James S. McDonnell Foundation,
Grant n° 220020449. We thank parents and children participating in this study and Baross,
J.. and Hegedűs A. for their help with data collection, and György Gergely for his valuable
comments on the manuscript. Special thanks to the Paris Institute of Advanced Studies, où
the first author was a Resident Fellow during writing up this paper.

DATA AVAILABILITY STATEMENT

The data that support the findings of this study are openly available in OSF at: https://osf.io
/c9zs5/.

INFORMATIONS SUR LE FINANCEMENT

This study was supported by the Momentum Program of the Hungarian Academy of Sciences
(LP-2017-17/2017). Partial funding came from the James S. McDonnell Foundation, Grant n
220020449.

CONFLICT OF INTEREST DISCLOSURE

The authors are in full consensus on the content of the manuscript and the ordering of authors.
All co-authors contributed to the present manuscript substantially, and will be informed about
any decisions regarding the manuscript by the corresponding author. There are no conflicts of
interests.

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Can 18-Month-Olds Revise Attributed Beliefs?

Király, Oláh, and Kovács

ETHICS APPROVAL STATEMENT

All the experiments presented in the paper were approved by the ethical committee of the Uni-
versity (Ethical Committee of the Eötvös Loránd University, Budapest, approval No.: 2018/126-2).

RÉFÉRENCES

Blankenship, T. L., & Kibbe, M.. M.. (2022). Two-year-olds use past
memories to accomplish novel goals. Journal d'expérimentation
Child Psychology, 214, 105286. https://doi.org/10.1016/j.jecp
.2021.105286, PubMed: 34500114

Boyd, R., & Richerson, P.-J. (1996). Why culture is common, but cultural
evolution is rare. Proceedings of the British Academy, 88, 77–93.
Byom, L., & Mutlu, B. (2013). Theory of mind: Mechanisms, méthodes,
and new directions. Frontiers in Human Neuroscience, 7, 413.
https://doi.org/10.3389/fnhum.2013.00413, PubMed: 23964218
Cheng, C., Kaldy, Z., & Blaser, E. (2019). Focused attention predicts
visual working memory performance in 13-month-old infants: UN
pupillometric study. Developmental Cognitive Neuroscience, 36,
Article 100616. https://doi.org/10.1016/j.dcn.2019.100616,
PubMed: 30769261

Crivello, C., & Poulin-Dubois, D. (2018). Infants’ false belief under-
standing: A non-replication of the helping task. Cognitive Develop-
ment, 46, 51–57. https://doi.org/10.1016/j.cogdev.2017.10.003
Dörrenberg, S., Rakoczy, H., & Liszkowski, U. (2018). Comment (pas) à
measure infant Theory of Mind: Testing the replicability and
validity of four non-verbal measures. Cognitive Development,
46, 12–30. https://doi.org/10.1016/j.cogdev.2018.01.001

Dudley, R., & Kovács, Á. M.. (2021). Do “knowledge attributions”
involve metarepresentation just like belief attributions do?
Behavioral and Brain Sciences, 44, Article e149. https://est ce que je
.org/10.1017/S0140525X20001594, PubMed: 34796829

Ganea, P.. UN., & Harris, P.. L. (2010). Not doing what you are told:
Early perseverative errors in updating mental representations via
langue. Child Development, 81(2), 457–463. https://est ce que je.org/10
.1111/j.1467-8624.2009.01406.x, PubMed: 20438451

Gerstenberg, T., Bechlivanidis C., & Lagnado D. UN. (2013). Back on
track: Backtracking in counterfactual reasoning. En M. Knauff,
M.. Pauen, N. Sebanz, & je. Wachsmuth (Éd.), Proceedings of
the 35th Annual Meeting of the Cognitive Science Society
(pp. 2386–2391). Cognitive Science Society.

Grosse Wiesmann, C., Friederici, UN. D., Chanteur, T., & Steinbeis, N.
(2017). Implicit and explicit false belief development in pre-
school children. Developmental Science, 20(5), Article e12445.
https://doi.org/10.1111/desc.12445, PubMed: 27696613

Kampis, D., Keszei, UN., & Király, je. (2018). Encoding third-person
epistemic states contributes to episodic reconstruction of memo-
ries. Behavioral and Brain Sciences, 41, 29–30. https://est ce que je.org/10
.1017/S0140525X1700139X, PubMed: 29353578

Király, JE., Oláh, K., Csibra, G., & Kovács, Á. M.. (2018). Retrospec-
tive attribution of false beliefs in 3-year-old children. Procédure
of the National Academy of Sciences of the United States of
America, 115(45), 11477–11482. https://doi.org/10.1073/pnas
.1803505115, PubMed: 30322932

Klein, S. B., Cosmides, L., Gangi, C. E., Jackson, B., Tooby, J., &
Costabile, K.-A. (2009). Evolution and episodic memory: Un
analysis and demonstration of a social function of episodic rec-
ollection. Social Cognition, 27(2), 283–319. https://est ce que je.org/10
.1521/soco.2009.27.2.283, PubMed: 23378680

Knudsen, B., & Liszkowski, U. (2012). 18-month-olds predict specific
action mistakes through attribution of false belief, not ignorance,
and intervene accordingly. Infancy, 17(6), 672–691. https://est ce que je
.org/10.1111/j.1532-7078.2011.00105.x, PubMed: 32693489

Kovács, Á. M.. (2016). Belief files in theory of mind reasoning.
Review of Philosophy and Psychology, 7, 509–527. https://est ce que je
.org/10.1007/s13164-015-0236-5

Kovács, Á.-M., Téglás, E., & Endress, UN. D. (2010). The social sense:
Susceptibility to others’ beliefs in human infants and adults. Sci-
ence, 330(6012), 1830–1834. https://doi.org/10.1126/science
.1190792, PubMed: 21205671

Liszkai-Peres, K., Kampis, D., & Király, je. (2021). The flexibility of
early memories: Limited reevaluation of action steps in
2-year-old infants. Journal of Experimental Child Psychology,
203, Article 105046. https://doi.org/10.1016/j.jecp.2020
.105046, PubMed: 33285338

Mahr, J., & Csibra, G. (2018). Why do we remember? The commu-
nicative function of episodic memory. Behavioral and Brain Sci-
ences, 41, 1–93. https://doi.org/10.1017/S0140525X17000012,
PubMed: 28100294

Martine, UN., & Santos, L. R.. (2016). What cognitive representations
support primate theory of mind? Tendances des sciences cognitives,
20(5), 375–382. https://doi.org/10.1016/j.tics.2016.03.005,
PubMed: 27052723

Phillips, J., Buckwalter, W., Cushman, F., Friedman, O., Martine, UN.,
Turri, J., Santos, L., & Knobe, J.. (2021). Knowledge before belief.
Behavioral and Brain Sciences, 44, Article e140. https://doi.org
/10.1017/S0140525X20000618, PubMed: 32895070

Schulze, C., & Buttelmann, D. (2022). Infants differentiate between
successful and failed communication in a false-belief context.
Infant Behavior and Development, 69, 101770. https://doi.org
/10.1016/j.infbeh.2022.101770, PubMed: 36113367

Schuwerk, T., Priewasser, B., Sodian, B., & Perner, J.. (2018). Le
robustness and generalizability of findings on spontaneous false
belief sensitivity: A replication attempt. Royal Society Open Science,
5(5), 172273. https://doi.org/10.1098/rsos.172273, PubMed:
29892412

Scott, R.. M., & Baillargeon, R.. (2017). Early false-belief understanding.
Tendances des sciences cognitives, 21(4), 237–249. https://est ce que je.org/10
.1016/j.tics.2017.01.012, PubMed: 28259555

Senju, UN., Southgate, V., Snape, C., Leonard, M., & Csibra, G.
(2011). Do 18-month-olds really attribute mental states to others?
A critical test. Sciences psychologiques, 22(7), 878–880. https://est ce que je
.org/10.1177/0956797611411584, PubMed: 21642553

Song, H. J., Onishi, K.-H., Baillargeon, R.. & Pêcheur, C. (2008). Can
an agent’s false belief be corrected by an appropriate communi-
cation? Psychological reasoning in 18-month-old infants. Cogni-
tion, 109(3), 295–315. https://doi.org/10.1016/j.cognition.2008
.08.008, PubMed: 18976745

Southgate, V., Chevallier, C., & Csibra, G. (2010). Seventeen-month-
olds appeal to false beliefs to interpret others’ referential commu-
nication. Developmental Science, 13(6), 907–912. https://doi.org
/10.1111/j.1467-7687.2009.00946.x, PubMed: 20977561

Sperber, D., & Wilson, D. (2002). Pragmatics, modularity and
mind-reading. Esprit & Language, 17(1–2), 3–23. https://doi.org
/10.1111/1468-0017.00186

Tauzin, T., & Gergely, G. (2018). Communicative mind reading in
infants. Rapports scientifiques, 8(1), Article 9534. https://est ce que je.org/10
.1038/s41598-018-27804-4, PubMed: 29934630

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