Psychology
2013. Vol.4, No.7A, 19-24
Published Online July 2013 in SciRes (http://www.scirp.org/journal/psych) http://dx.doi.org/10.4236/psych.2013.47A003
Ostensive Cues Orient 10-Month-Olds’ Attention toward the
Task But Delay Learning
Rana Esseily1, Jacqueline Fagard2
1Laboratoire Ethologie, Cognition et Développement, Université Paris Ouest Nanterre, La Défense, France
2Laboratoire Psychologie de la Perception, UMR 8158, CNRS-Université Paris Descartes, Paris, France
Received April 23rd, 2013; revised May 25th, 2013; accepted June 22nd, 2013
Copyright © 2013 Rana Esseily, Jacqueline Fagard. 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 aim of this study is to investigate how ostensive cues modify infants’ visual attention to task dem-
onstration, and the extent to which this enhances the performance in an imitative learning task. We hy-
pothesized that ostensive cues would help orient infants’ attention toward relevant parts of the demonstra-
tion. We investigated the looking behavior of 41 10-month-old infants while observing an adult demon-
strating a novel target action after having either provided ostensive cues or not. Infants’ looking behavior
was measured using an eye tracker. Two areas of interest were analyzed: the targeted object and the
adult’s face. Infants’ performance after demonstration was also analyzed. The results show that infants’
looking behavior varied across groups. When ostensive cues were not provided, infants looked mainly at
the experimenter’s face. However, when ostensive cues were provided, infants oriented their attention
toward the targeted object. These results suggest that ostensive cues help infants orient their attention to-
ward task-relevant parts of the scene. Surprisingly, infants in the non-ostensive group improved their per-
formance faster after demonstration than infants in the ostensive group. These results are discussed in
terms of a video effect and dissociation between separate cognitive systems for social and non-social cog-
nition.
Keywords: Ostensive Cues; Attention Orientation; Eye Tracking; Imitative Learning
Introduction
Over the last five years, an emerging body of research has
been showing how infants’ imitative learning capacities are
enhanced when the experimenter communicates with the infant
before or during the demonstration of a target action. The
communication used in these studies can be social interaction
unrelated to the task (e.g. playing with the infant before testing)
(Nielsen, Simcock, & Jenkins, 2008) or ostensive cues directly
related to the target action (Brugger, Lariviere, Mumm, &
Bushnell, 2007; Carpenter, Call, & Tomasello, 2005; Esseily,
Rat-Fischer, O’Regan, & Fagard, 2013; Southgate, Chevallier,
& Csibra, 2009; Topàl, Gergely, Miklosi, Erdohegyi, & Csibra,
2008). In this paper we focus exclusively on how ostensive
cues modify the infant’s visual attention to the demonstration
and the resulting effects on performance. Ostensive cues in-
clude visual and auditory cues such as eye contact, eyebrow
raising, infant-directed speech, saying the infant’s name, illus-
tration of the experimenter’s intention, etc. Csibra and Gergely
(2009) hypothesized that ostensive cues enhance infants’ per-
formance by guiding them to the information to be learned,
hence leading infants to pay more attention to the demonstra-
tion. However, to our knowledge, it has not yet been empiri-
cally shown that ostensive cues guide infants’ attention in an
imitative learning task. One way to test this hypothesis is to
measure infants’ looking behavior in an imitative learning task
while the experimenter is demonstrating a target action after
having provided ostensive cues (or not). The goal of this study
was to see whether ostensive cues actually help infants orient
their attention to the demonstrated target action.
A number of studies have focused on the effect of ostensive
cues on infants’ reproduction of a demonstration. Some studies
have found that infants primarily imitate effective ways of
achieving goals, ignoring apparently unnecessary actions unless
the demonstrator makes it manifest to them through ostensive
cues that these actions are relevant to the task (Brugger, La-
riviere, Mumm, & Bushnell, 2007; Carpenter, Call, & Toma-
sello, 2005; Carpenter, Nagell, & Tomasello, 1998; Gergely,
Bekkering, & Kiràly, 2002; Nielsen, 2006; Southgate, Cheval-
lier, & Csibra, 2009). In study of Brugger et al. (2007) for ex-
ample, infants saw a model perform a multi-step action in
which the first action was either necessary or unnecessary to
attain the goal. They showed that when the experimenter pro-
vided ostensive cues by speaking directly to the infant before
performing the first action, thus marking that action as an im-
portant step, the action was imitated in both the necessary and
unnecessary conditions, showing the importance of ostensive
cues in a learning context. In a slightly different procedure,
showing the experimenter’s intention or goal before demonstra-
tion of the target action was shown to improve infants’ per-
formance in an imitative learning task (Esseily, Rat-Fischer,
O’Regan, & Fagard, 2013). In this study, 16-month-old infants
were shown a novel means-end action (retrieving an out-of-
reach toy using a tool). The authors observed that infants

R. ESSEILY, J. FAGARD
tended to ignore the demonstration and tried to reach directly
for the object with their bare hand. However, in the condition
when the experimenter tried to reach for the object with bare
hand while saying “I can’t get it” before providing the demon-
stration, infants reproduced the action of using the tool signifi-
cantly more frequently.
The question we raise in this paper is why infants’ imitative
learning performance is better when ostensive cues are pro-
vided. Do these cues guide infants’ attention? Some studies
using joint attention tasks have tried to answer this question.
These studies have investigated what infants attend to, depend-
ing on eye contact conditions, using gaze direction measure-
ments (Senju & Csibra, 2008; Senju, Csibra, & Johnson, 2008).
The results showed that infants follow an experimenter’s gaze
toward an object only if the experimenter makes eye contact
with the infant before a gaze shift toward the object. However,
few existing studies have investigated what infants attend to in
an imitative learning task when ostensive cues are provided
before or during demonstration.
Thus, in the study presented here, we sought to test infants'
attention through gaze direction measurements during an
adult’s demonstration of a novel target action after either pro-
viding ostensive cues or not. We suppose here that an infants’
gaze reflects what they are attending to in a scene. We hy-
pothesized that ostensive cues would direct infants’ gaze to the
part of the demonstration that is relevant for learning, namely
the action performed or the object manipulated. By contrast,
when no ostensive cues are provided, infants may be less likely
to know where to look in the demonstration, and their attention
may be attracted to salient but less relevant targets such as the
experimenter’s face (e.g. Franck, Vul, & Johnson, 2009; Hen-
richs, Elsner, Elsner, & Gredebäck, 2012).
Because ostensive cues partly rely on infants’ joint attention
capacities (Gergely & Csibra, 2006) and because infants' joint
attention has been shown to emerge around 10 months of age
(Carpenter, 1998), we decided to investigate 10-month-old in-
fants’ looking behavior when presented with an adult demon-
strating a complex target action. The target action consisted of
holding an opaque wooden container with one hand and pulling
out an inserted transparent tube with the other hand, an action
that infants are known to be spontaneously successful at around
the age of 11 months (Fagard, 1998). Infants observed a movie
of the adult demonstrating the target action, either preceded by
ostensive cues or not. The use of video was based on a previous
study in which we showed that 10-month-old infants were ca-
pable of imitating novel means-end actions from video models
(Esseily & Fagard, 2012).
Infants' looking behavior was measured using an eye tracker.
We also compared infants’ performance before and after dem-
onstration in each of the two groups. We expected to observe
better learning capacities in the ostensive group as compared to
the non-ostensive group.
Method
Participants
A total of 41 healthy full-term infants participated in this ex-
periment (22 females). The mean age at the time of testing was
10 months (range: 9 months 7 days to 10 months 13 days). The
infants were recruited from a local list of families who ex-
pressed interest in participating in the study. Parental consent
was granted before observing the infants.
Materials
We chose a target action that is rarely successfully performed
spontaneously at the age tested (Fagard, 1998). It consisted in
pulling a tube out of a container with one hand while holding
the container with the other hand, thus requiring bimanual co-
ordination of complementary movements. The transparent plas-
tic cylindrical tube (12 cm long × 1.5 cm diameter) with an
orange cap was inserted into a wooden container 9 cm long ×
2.5 cm wide.
Procedure
Testing occurred in the university infant testing room. The
infant sat at a table on a parent’s lap. Parents were asked not to
interfere with their infants’ activity. Once the infants were
judged to be accustomed to their surroundings and comfortable,
testing began. Infants were randomly assigned to one of the two
groups: a non-ostensive group (n = 20) where infants observed
a movie of an adult performing the target action; and an osten-
sive group where infants observed a movie of an adult looking
at them and addressing them in infant-directed speech saying
“Hi baby, look!” before performing the target action (n = 21).
Videos were used to ensure that ostensive cues were compara-
ble for all participants. The experimenter who modelled the
target action was a stranger to the infants, and different from
the experimenter testing the infants.
In both groups, the model repeated the demonstration three
times in a row for a total duration of approximately 12 seconds.
The video was displayed on a 17” LCD screen placed on the
table at 70 cm from the infant. In both groups, the video began
with an attractive image of a cartoon character with music to
draw infants’ attention toward the screen.
Each infant was assigned randomly to one of the two groups,
and went through four trials. The first was a spontaneous trial
where infants played with the object during one minute of free
manipulation. The second, third and fourth trials were test trials,
each consisting in one minute of manipulation and each pre-
ceded by the same video demonstration, corresponding to the
infant’s group (ostensive or non-ostensive). We decided to
show each infant the demonstration three times because of the
video deficit effect observed in many other studies: additional
exposure is needed when the demonstration is presented on
video rather than live (Barr, Dowden, & Hayne, 1996; Barr &
Hayne, 1999; Barr, Muentener, Garcia, Fujimoto, & Chavez,
2007). During the demonstration, the experimenter stood be-
hind the infant and the parents, and the real object was put out
of the infant’s sight. During testing, the experimenter stood
facing the infant and handed the object to her. A video camera
recorded the infant’s behaviour during the whole experiment.
The whole session lasted a maximum of 10 minutes.
Eye Tracking
A Tobii X120 eye tracker and a screen were placed at a dis-
tance of 70cm from the infant’s eyes. Gaze direction was re-
corded using a Tobii studio program. The infant’s line of gaze
was computed by the eye tracker based on the pupil-corneal
reflection at a sampling rate of 120 Hz.
The experiment started with a calibration. The experimenter
turned on the calibration stimulus, a bouncing ball, whenever
the infant was looking at the screen. Five points of calibration
were used, one at each corner of the screen and one at the cen-
20

R. ESSEILY, J. FAGARD
tre. If the infant looked away during the calibration, an ani-
mated stimulus popping on the screen was used to redirect the
infant’s gaze toward the screen, and the experimenter calibrated
the missing points.
Coding
Eye Tracking Analysis
Data from the eye tracker were analyzed using the Tobii stu-
dio software. Fixation times were first calculated on three areas
of interest (AOI): face, tube and container. At the beginning of
the video, the tube is inside the container and only the cap of
the tube is visible. The model holds the container still during
the demonstration and pulls the tube out of it in a linear move-
ment. As the tube and the container are both part of the same
object, we decided to pool the two parts together in the same
area of interest, called “object”. Thus, two areas were ultimately
considered: the face and the object (tube + container). In the
two groups, the face occupied 1.32% of the screen and the ob-
ject 0.73%. Fixations away from both the face and the object
were considered to be out of areas of interest (OAOI). Fixation
points were easy to code on relatively static areas like the face
and the container. To code dynamic areas like the tube, we did
a frame-by-frame analysis to mark each fixation’s correspond-
dence to the movement of the tube.
We analyzed the following data: total fixation time on the
demonstration (including both AOI and OAOI fixation times),
and fixation time on each AOI.
As mentioned in the procedure section, each demonstration
was repeated three times on each trial, for a total duration of
approximately 12 seconds. Thus, each demonstration lasted
approximately four seconds. We first analysed data separately
for the three demonstrations. We found no significant differ-
ence in AOI and OAOI fixations between the three demonstra-
tions, and thus, to simplify the results, we present the mean
AOI and OAOI fixations over the three demonstrations in the
first trial. We had eye tracking data for all three trials, but be-
cause of substantial data loss from the second and third trials,
only the eye tracking data from the first trial will be presented
here. This was because infants were more distracted in the sec-
ond and third trials than in the very first trial where attention
was at its maximum.
When the effects were not significant, we calculated the ef-
fect size using Cohen’s d (Cohen, 1977).
Behavioral Analysis
The video recordings were coded by two independent ob-
servers. Infants’ spontaneous activity and behaviour after each
demonstration was coded in relation to the target action. A
behaviour was coded as the target action if the infant removed
the tube from the container bimanually (holding the container
with one hand and pulling the tube with the other hand).
Non-target actions with the tube included shaking the tube,
putting it into the mouth, or striking the table with it. If by
chance these manipulations led to the tube leaving the container,
or if the infants pulled the tube out of the container unimanually,
which happened only three times, we gave the object back to
the infant to check whether the action would be intentionally
repeated. If the infant re-enacted the action bimanually, it was
coded as a success.
For each group, the arcsine transformation of the percentage
of infants who produced the target action during spontaneous
activity and during the test trials following demonstration was
compared. If infants imitatively learned the target action, then a
significant increase was expected in the percentage of infants
producing the target action after the demonstrations as com-
pared to the spontaneous trial. There was 100% agreement on
the possible outcomes between the two observers.
Results
Eye Tracking
We obtained eye tracking data for 37 out of the 41 infants
(20/20 in the non-ostensive video group and 17/21 in the osten-
sive video group), because of technical problems with the eye
tracker that occurred during the experiment with the remaining
subjects.
We will first present fixations on the screen, then fixations
on the areas of interest: the face and the object (AOI), as well as
fixations out of areas of interest (OAOI).
Total Fixation Time on the Demonstration
The time infants spent looking at the screen in the non-os-
tensive group and the ostensive group was 3.7 seconds (SD =
0.7) and 3.5 seconds (SD = 1.2) respectively. An ANOVA on
fixation time with group as an independent measure showed no
main effect of group. Thus, infants in both groups looked
equally at the overall demonstration.
Fixation Time on AOI and OAOI
As can be seen in Figure 1, infants in the ostensive group
looked less out of the area of interest (OAOI) than infants in the
non-ostensive group. In both groups, infants looked more at the
model’s face than at the object. However, in the non-ostensive
group, infants looked more than twice as much at the face (2.06)
than at the object (0.8), whereas in the ostensive group, the
difference between time of fixation on the face (1.78) and on
the object (1.34) was much smaller. An ANOVA with fixation
time on the face, on the object and OAOI as dependent meas-
ures and group as independent measure showed a main effect of
group (F (2), 32) = 3.9; p = .01). A post hoc LSD test showed
that the main effect was due to the difference in fixation times
on the object (p = .03) and OAOI (p = .01). There was no sig-
nificant difference for fixations on the face. A one-sample t-test
Figure 1.
Fixation times on the face, on the object and OAOI as a function of
group.

R. ESSEILY, J. FAGARD
conducted separately for each group on time spent looking at
the face and at the object showed that the difference was sig-
nificant in the non-ostensive (T (18) = 3.19, p < .01) but not in
the ostensive group.
Thus, infants in the ostensive group looked less outside the
areas of interest and fixated the object more than infants in the
non-ostensive group.
Percentage of Infants Producing the Target Action
The percentage of infants who produced the target action in
the spontaneous and test trials is presented in Table 1. A gen-
eralized linear model was used to compare the percentage of
infants who spontaneously produced the target action, and no
effect of group was found. This suggests that the groups were
equivalent in terms of spontaneous manipulation, and therefore
can be compared for the trials after demonstration.
To check for an effect of ostensive cues on performance after
demonstration, we compared the spontaneous trial with the
three trials after demonstration by performing a 4 (trial, re-
peated measures) × 2 (group) ANOVA on the arcsine transfor-
mation of the percentage of infants who produced the target
action. We found a main effect of trial (F (3, 114) = 8.6; p
< .01), no main effect of group, and no Group x Trial interac-
tion. The percentage of infants who produced the target action
increased significantly after demonstration compared to the
spontaneous trial. A post-hoc LSD analysis indicates that the
trial effect is due to a significant change between the spontane-
ous trial and the first test trial in the non-ostensive group (p
= .01), and a significant change between the spontaneous trial
and the third test trial (p = .002) in the ostensive group.
Thus, infants improved their performance right after the first
set of demonstrations in the non-ostensive group, but only after
the third set of demonstrations in the ostensive group.
Discussion
The goal of this experiment was to investigate how ostensive
cues modify infants’ visual attention to demonstrations, and the
extent to which this enhances performance. Our hypothesis was
that the role of ostensive cues provided before demonstration is
to orient infants’ attention to the actions to be learned. In the
absence of ostensive cues, instead of looking at the demonstra-
tion, infants would instead be attracted by salient targets. In
particular, the face is known to attract infants’ attention when
observing a complex scene as early as 3 months of age (Frank,
Vul, & Johnson, 2009; Henrichs, Elsner, Elsner, & Gredebäck,
2012). We tested our hypothesis using gaze direction measure-
ment to examine infants’ looking behaviour while they were
showng a demonstration of a target action, either preceded by
ostensive cues or not.
Eye tracking results show that infants spent at least half of
the time of the demonstration looking at the face of the model
Table 1.
Percentage of infants performing the target action as a function of trials
and groups.
Spontaneous Test 1 Test 2 Test 3
Non-ostensive
(N = 21) 25% 45%
45% 55%
Ostensive
(N = 20) 19% 19% 35%
45%
whether ostensive cues were provided or not. One interpretation
could be that infants are seeking information about the novel
task by looking at the model’s eyes to establish the direction of
her gaze, or through her emotional expressions. This behaviour,
known as social referencing, is typically seen in ambiguous
situations, when strangers are present for example (e.g. Fein-
man & Lewis, 1983). Social referencing studies demonstrate
that infants look at adults and use some of the ostensive cues
that adults provide to guide their behaviour. Indeed, our results
confirm these conclusions: even though infants in the ostensive
group looked at the object manipulated, most of them first
made eye contact with the model before directing their gaze to
the object, showing social referencing.
Our eye tracking data also show that infants looked more at
the targeted object in the presence of ostensive cues than in
their absence, thus confirming our hypothesis. In addition, in-
fants in the ostensive group looked less outside the areas of
interest (face and object) than infants in the non-ostensive
group, suggesting that ostensive cues help infants focus their
attention on the demonstration. These results are in accordance
with studies on joint attention showing that infants look at a
manipulated object more if the experimenter provides ostensive
cues such as eye contact (Senju & Csibra, 2008; Senju, Csibra,
& Johnson, 2008).
Considering these eye tracking results as well as studies
showing the positive effect of ostensive cues on learning, we
expected better imitative learning performance when the ex-
perimenter provided ostensive cues before performing the
demonstration. Surprisingly, we found instead that infants in
the non-ostensive group learned the target action significantly
faster than infants in the ostensive group.
Even though these results may initially seem surprising, they
may be partly explained by a video effect. Indeed, 10-month-
olds may be surprised to see an adult on a video making eye
contact and addressing them with infant-directed speech. Some
studies have shown that infants and older children do not al-
ways believe that characters on a screen can engage in real
communicative interaction (Claxton & Ponto, 2013) and do not
always use information from videos to solve a real-world prob-
lem. For example, Troseth, Saylor, & Archer (2006) showed
that 2-year-old children who were told face-to-face where to
find a hidden toy found it, but children who were given the
same information by a person on video did not. In the same
study, children who engaged in a 5-minute contingent interac-
tion with a person (including social cues and personal refer-
ences) through closed-circuit video before the hiding task used
information provided to find the toy. Taken together, these
studies suggest that the video effect is due to a lack of interac-
tion between the experimenter and the infant. Indeed, the re-
sults of the two additional test trials in our study show that the
performance of infants in the ostensive group improved gradu-
ally over the second and third trials, and their results eventually
became comparable to those of the infants in the non-ostensive
group. These results favour a surprise effect that fades away
with repeated exposure to the video and to ostensive cues,
leading to better performance. It would have been interesting to
see how looking behaviour changed across trials.
Another non-exclusive explanation may contribute to ex-
plaining this apparent contradiction between the greater atten-
tion that infants in the ostensive group pay to the object and
their less successful performance in comparison to infants in
the non-ostensive group. It may be that social and non-social
22

R. ESSEILY, J. FAGARD
cognition depend on separate cognitive systems, as some au-
thors have claimed (Gelman & Spelke, 1981; Legerstee, 2006;
Spelke & Kinzler, 2006). Thus, when the social system faces a
load of ostensive cues, infants may need time to process the
social information at the cost of neglecting the cognitive as-
pects, in this case pulling apart the tube and the container using
bimanual coordination. The results fit with this alternative ex-
planation, given that infants in the ostensive group needed more
time to succeed at performing the task than infants in the non-
ostensive group: this may reflect the time needed to process the
social information provided by the experimenter. Thus, it would
be interesting to test this hypothesis by varying the social and
the cognitive loads in a single experiment, to see whether a
trade-off could be observed between the two systems.
Finally, even though the rate of success after the first demon-
stration was higher in the non-ostensive group, it remains low,
since only 20% out of the 75% of infants who failed spontane-
ously reproduced the target action after demonstration. Two
reasons may explain this low success rate. First, some studies
have shown that 10-month-old infants have limited imitative
learning capacities, and it is not until 12 to 15 months of age
that infants begin to learn novel tasks by imitation (Elsner,
Hauf, & Aschersleben, 2007; Esseily, Nadel, & Fagard, 2010;
Fagard & Lockman, 1998). Second, even though demonstration
via video has been tested in previous studies (Esseily & Fagard,
2012), others have shown a video deficit effect (Barr, Dowden,
& Hayne, 1996; Barr & Hayne, 1999; Barr, Muentener, Garcia,
Fujimoto, & Chavez, 2007; Zack, Barr, Gerhardstein, Dicker-
son, & Meltzoff, 2009). This effect may have contributed to the
low success rate.
In conclusion, this is the first eye tracking study to show that
ostensive cues can serve as a pointer directing infants’ attention
to important elements of a demonstration. However, when os-
tensive cues are provided, infants may be “distracted” by the
social information and ignore the cognitive task. This might be
particularly true at young ages when infants’ social and cogni-
tive capacities are limited. Thus, it would be interesting to pur-
sue this study with older infants to see whether resolving the
task becomes easier with improvement in the capacity to proc-
ess social and cognitive stimuli at the same time.
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