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Abstract

Background: One issue that has received relatively little attention in the analyses of the neophobic responses to a novel flavor is the influence of the context in which the flavor is first encountered, along with the effect of this context on the habituation of neophobia when the flavor is repeatedly consumed. Considering the predictions of the Contextual Safety Hypothesis, which proposes that the previous appetitive or aversive history of the context will modulate the intensity of neophobia and its habituation, we designed an experiment to evaluate the role played by the context in neophobia and its habituation to a new flavor. Method: Male Wistar rats had access to a new flavor solution (0.1% sacharin) in presence of a context previously submitted to a treatment intended to turn it into appetitive, aversive or merely familiar. An additional group of rats received the new flavor in their home cages. Results: After four days of saccharin exposure, those animals in the Appetitive and Home conditions showed significant faster neophobia habituation as compared to those in the Aversive and Familiar groups. Conclusions: These results revealed the potential applied value of using contextual manipulations to promote healthy eating behavior both in animals and humans.
617
The considerable differences in food preferences observed
between individuals are clearly indicative of the importance of
experience and learning —along with genetic predisposition— in the
development of food preferences (e.g., Birch, 1999). One mechanism
that has evolved and is part of the foundation of food preferences and
rejections is avor neophobia, expressed behaviorally by the reduced
consumption of a novel avor in comparison with consumption of an
already familiar avor (see, for a review, Reilly, 2018). Neophobia
tends to habituate progressively when the avor is repeatedly
consumed without being followed by aversive consequences,
resulting in a progressive increase of consumption across successive
encounters with the avor (e.g., Domjan, 2018).
The neophobia habituation process has traditionally been
considered an example of non-associative learning, but there is recent
evidence indicating that neophobia habituation shares neural circuits
with mechanisms of declarative memory (Grau-Perales et al., 2019;
Morillas et al., 2017), thus representing a more complex form of avor
memory. In fact, neophobia habituation has been proposed, along
with other classical conditioning processes, as a learning mechanism
that determines the acquisition of preference or rejection to speci c
avors (e.g., Reilly, & Schachtman, 2009; Sclafani, 1995).
Considering that the role of context in which the avor is rst
encountered has received little attention in previous research on
neophobia and neophobia habituation, we conducted an experiment
analyzing the effects of such variable on consumption of a new
avor (saccharin) in laboratory rats. Previous results showed that
presenting a new avor in presence of a new context resulted in
a reduction in consumption compared with the case in which the
animals received the novel avor in an already familiar context
(e.g., De la Casa et al., 2003). These results were interpreted as the
result of a non-associative process induced by the new context that
increased the level of arousal of the animals, which consequently
resulted in an increase in the exploratory responses that compete
with taste consumption (Honey et al., 1992). More recently,
some experimental results have revealed that the role of context
in neophobia and its habituation goes beyond its mere novelty or
familiarity. Thus, De la Casa (2018) have proposed the so-called
ISSN 0214 - 9915 CODEN PSOTEG
Copyright © 2021 Psicothema
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Context Properties Modulate Flavor Neophobia Habituation
Lucía Vicente1, and Luis Gonzalo De la Casa2
1 Universidad de Deusto, and 2 Universidad de Sevilla
Abstract Resumen
Background: One issue that has received relatively little attention in
the analyses of the neophobic responses to a novel avor i s the in uence
of the context in which t he avor is rst encountered, along with the
effect of this context on the habituation of neophobia when the avor
is repeatedly consumed. Considering the predictions of the Contextual
Safety Hypothesis, which proposes that the previous appetitive or aversive
history of the context will modulate the intensity of neophobia and its
habituation, we designed an experiment to evaluate the role played by
the context in neophobia and its habituation to a new avor. Method:
Male Wistar rats had access to a new avor solution (0.1% sacharin) in
presence of a context previously submitted to a treatment intended to turn
it into appetitive, aversive or merely familiar. An additional group of rats
received the new avor in their home cages. Results: After four days of
saccharin exposure, those animals in the Appetitive and Home conditions
showed signi cant faster neophobia habituation as compared to those in
the Aversive and Familiar groups. Conclusions: These results revealed
the potential applied value of using contextual manipulations to promote
healthy eating behavior both in anima ls and humans.
Keywords: Neophobia; habituation; context; eating behavior.
Las Propiedades del Contexto Modulan la Habituación de la Neofobia
Gustativa. Antecedentes: la in uencia del contexto en presencia del que
aparece un sabor nuevo sobre la neofobia gustativa y su habituación es un
as p ec to que ha re ci bi do re lat iv am en te po ca at en ci ón en l a i nv es tig ac ió n. En
este artículo describimos un experimento diseñado pa ra evaluar el papel
que juega el contexto sobre la neofobia y su habituación partiendo de las
predicciones de la Hipótesis de Segu ridad Contextual, que propone que
la historia previa apetitiva o aversiva del contexto modulará la intensidad
de la neofobia y su habituación. Método: se expuso una muestra de ratas
Wistar macho a una disolución de un sabor nuevo (sacarina al 0,1%) en
presencia de un contexto previamente sometido a un tratamiento diseñado
para convertirlo en apetitivo, aversivo o meramente familiar. Un grupo
adicional de ratas recibió el nuevo sabor en sus jaulas hoga r. Resultados:
después de cuatro días de exposición a la sacarina, los animales en las
condiciones Apetitivo y Hogar mostraron una habituación a la neofobia
signi cativamente más rápida que los de los gr upos Aversivo y Familiar.
Conclusiones: estos resultados revelan el potencial valor aplicado del uso
de manipulaciones contextuales para promover conductas alimentarias
saludables tanto en animales como en humanos.
Palabras clave: neofobia; habituación; contexto; conducta alimentaria.
Psicothema 2021, Vol. 33, No. 4, 617-622
doi: 10.7334/psicothema2021.164
Received: May 3, 2021 • Accepted: July 28, 2021
Corresponding author: Luis Gonzalo De la Casa
Dpto. Psicología Experimental
Universidad de Sevilla
41018 Sevilla (Spain)
e-mail: delacasa@us.es
Article
Lucía Vicente, and Luis Gonzalo De la Casa
618
contextual safety hypothesis, which proposes that the appetitive
or aversive features of a speci c context will serve to modulate
consumption of the novel avor. Therefore, when appetitive
consequences consistently appear in a speci c context, as occurs,
for instance, in the animals’ home cages, such a context will acquire
safety properties that will be transferred to any novel stimuli
that appear in its presence. Conversely, if aversive stimuli have
appeared in the context, then the latter will become a predictor of
aversive consequences, which will affect responding to any stimuli
that are presented in this context in the future.
Departing from this hypothesis, the main purpose of the
present experiment was to assess water-deprived male Wistar rats
consumption of a novel saccharin solution for a 10-min period on
four consecutive days as a function of context. Speci cally, those
animals in the Appetitive (App) Group were tested in a context
that previously had been paired with food (half salty cracker) and
subjected to an environmental enrichment treatment (e.g., Birch et
al., 2013; Simpson & Kelly, 2011) for endowing the context with
appetitive properties. It has been proven that pairing a context with
food (Mustaca et al., 1991), or with new stimuli (e.g., Bevins et al.,
2002) has rewarding properties as showed by place preference tests.
The rats in the Aversive (Avers) Group were tested in presence of a
context that had been paired with the presentation of mild shocks.
In addition, two groups were included in the experimental design:
A Familiar (Fam) Group, tested in presence of a context that was
already familiar, and a Home Group for which the experimental
context was the rats’ home cages, since this context has already
been shown to attenuate neophobia and expedite its habituation
(e.g., De la Casa et al., 2013).
According to the predictions derived from the Contextual Safety
Hypothesis, we expected to observe increased neophobia and
slower habituation to neophobia when a novel avor is presented in
the aversive context, but reduced neophobia and faster habituation
to neophobia in the appetitive context and in the rat´s home cage.
Regarding the group tested in the familiar context, we expect an
increase of neophobia and slower habituation as compared to
Home and App groups, but a reduced effect of neophobia and faster
habituation as compared to the Avers group, since in the Fam group
the effect of neophobia would not be affected by novelty nor the
appetitive or aversive properties of the context (De la Casa, 2018).
We registered two dependent variables: uid consumption for
all animals, that was considered as an index of neophobia and its
habituation, and mean percentage of locomotor activity for those
rats in App, Avers, and Fam groups, as an indirect way of evaluating
the effectiveness of the experimental treatments in endowing the
contexts with appetitive or aversive properties (e.g., Rescorla et
al., 1985).
Method
Participants
32 male Wistar rats, (n=8 per group) with weights ranging from
290 to 455 g participated in this experiment. At the arrival to the
laboratory, the animals were housed in groups of 2/3 (depending
on the animals’ weight) in type IIIH cages (820 cm2), with wood
shavings as bedding and other materials available in the cages (pieces
of fabric, cardboard and wood, stones, etc.), except for the time
they were submitted to the experimental procedure when they were
individually housed to obtain a better control for water/food intake
across the experimental procedure. Speci cally, after a two weeks
period of adaption to the vivarium, the animals were individually
housed in 40 × 20 × 24 cm Plexiglas cages with wood shavings as
bedding and maintained on a regular 12:12-h light/dark cycle (lights
on at 07:00 A.M.) during the experimental period. All behavioral
testing was conducted during the light period of the cycle, starting
at 9:00 A.M. The vivarium was illuminated by four 100W bulbs.
All animals were placed on a water deprivation schedule (30 min/
day access to water) that was maintained across the entire duration
of the experiment. All experimental procedures were approved by
the Ethics Committee for Animal Research of University of Seville
(code number CEEA-US2015-28/4), and conducted in agreement
with the guidelines established by the EU Directive 2010/63/EU for
animal experiments, and the Spanish R.D. 53/2013.
Instruments
All experimental sessions were conducted either in the home
cages of the animals for Group Home, or in four experimental
chambers (Panlab, model LE 111) designed to detect and record
mean percentage activity for App, Avers, and Fam groups. Each
chamber was enclosed in a soundproofed module (model LE 116),
and the oor of the experimental chambers was composed of
stainless steel rods, 2 mm in diameter, spaced 10 mm apart (center
to center), resting on a platform that registered and recorded each
animal’s movements, which were then converted into analog signals
by a piezoelectric unit attached to the platform. These signals were
digitized and stored by a computer as a linear parameter. All uids
were provided at room temperature in 150 ml graduated plastic
bottles, tted with stainless steel spouts. The bottles were attached
to the front wall of each cage during the experimental drinking
sessions. The amount of uid intake was measured by calculating
the difference between the weight of the bottle before and after uid
presentation. The avor was a 0.1 % sodium saccharin solution
dissolved in tap water. A 0.5 mA, 1-sec unscrambled AC 50-Hz
foot shock from a constant-current generator (Model LE100-26)
was delivered to the oor of each chamber, as described in the
Procedure section for the Avers Group. For the App Group, a 5 × 5
cm piece of fabric, a cardboard tube from a toilet paper roll, a 5 ×5
cm egg carton, and half of a salty cracker were introduced inside
the experimental context for each trial.
Procedure
The rats were randomly assigned to the Home, App, Avers, and
Fam groups. On the rst day of the experiment, a water deprivation
schedule (with each animal having daily access to 30-min of uid)
was implemented and maintained for the entire duration of the
experiment.
From Days 2 to 5, animals in the App, Avers, and Fam groups
were introduced into the experimental cages where they remained
for 60-min each day. The animals in the Home group were simply
removed and immediately returned to the home cages. The rats in
the Avers group received 3 shocks on each session (0.5 mA, 1 sec.)
with a mean inter-shock interval of 15 min (+/- 5 min). The rats in the
App group were allowed to eat the half salty cracker and to interact
with the stimuli described in the Apparatus section (introduced into
the experimental cages as a means of producing environmental
enrichment). The animals in the Fam group remained for 60-min in
the experimental cages without any additional stimulation. In order
Context Properties Modulate Flavor Neophobia Habituation
619
to equate the experience with the salty cracker that was presented
during the environmental enrichment trials for the App group, half
of a salty cracker was placed in each home cage for the animals in
the Fam, Avers, and Home groups on each day of this phase. After
the experimental treatment, all animals had access to 30-min of
water in their home cages in the same bottles that were used during
the neophobia trials.
On Days 6 and 7 the animals remained undisturbed in their home
cages and received water for the corresponding 30-min period.
From Days 8 to 11, all animals received 10-min access to the
0.1 % saccharin solution in the corresponding experimental (Fam,
App, and Avers groups) or home cages (Home group) to evaluate
the intensity of neophobia and subsequent habituation of this
response. No additional stimuli were introduced at testing. The
bottles were weighed before and after each session, and the mean
percentage of motor activity was recorded for App, Avers, and Fam
groups on each session.
To evaluate the effect of context on neophobia and its habituation
we analyzed mean saccharin intake on each day. Neophobia
would induce differences in consumption across groups on the
rst day, and neophobia habituation would result in differences
in consumption across successive days. In addition to saccharin
consumption, we recorded the percentage of locomotor activity for
the rats in the App, Avers, and Fam groups on the neophobia tests
in order to detect whether the appetitive or aversive properties of
the context induce different levels of activity.
Data analysis
All statistical analyses were conducted with the version 24 of
the statistical program SPSS. We explored our hypotheses using
repeated measures mixed ANOVAs, with Trials (within-subject),
and Groups (between-subject: Fam vs. Home vs. Avers vs. App) as
main factors. LSD post-hoc comparisons between all groups, and
analyses of simple effects using a α-level of 0.05 were conducted to
identify the source of the signi cant main effects and interactions.
In order to discard any potential effect of differences in rats’
weight at the start of the experiment on consumption, an ANOVA
with main factor Groups was performed on such variable. The
analysis revealed that there were no signi cant differences between
groups, F(3,21)<1.
Figure 1 depicts mean saccharine consumption as a function of
groups for the four test days. As can be seen in the Figure, there
was a general effect of neophobia habituation across trials that was
faster for the Home and App groups as compared to the Avers and
Fam groups.
The ANOVA conducted on mean saccharine consumption
revealed a signi cant main effect of Trials, F(3,84)=10.88; p<.001;
η2=.28, re ecting the overall effect of neophobia habituation across
trials. The main effect of Groups was also signi cant, F(3,26)=2.09;
p<.05; η2=.33, revealing that mean consumption was different
between groups. Post hoc comparisons between groups (p<.05)
performed on such dependent variable revealed that the main effect
of Groups was due to higher mean saccharin consumption for the
Home and App groups (Mean = 8.65 ml., SEM = .58 and Mean =
9.15 ml., SEM = .75, respectively) as compared to the Fam and
Avers groups (Mean = 6.76 ml., SEM = .38, and Mean = 6.39 ml.,
SEM = .77, respectively). Finally, the Trials × Groups interaction
was also signi cant, F(9,84)=3.03; p<.01; η2=.18. In order to
explore the interaction we conducted separate repeated measures
ANOVAs with Trials as the main factor on mean consumption
for each group, and ANOVAs between groups for each trial. The
repeated measures ANOVAs revealed a signi cant effect of Trials
for the App, Home, and Avers groups, Fs(3,21) > 4.1; ps<.05;
ηs2>.37, due to an increase in consumption across trials indicating
the habituation of neophobia to the new avor. The effect of Trials
was non-signi cant for the Fam group, F(3,21)<1.
An ANOVA with Groups as main factor conducted on mean
consumption for each trial revealed signi cant differences between
groups for the second, third, and fourth trial, Fs(3,28) > 3.48; ps<.05;
ηs2>.27. Post hoc comparisons between groups (p<.05) revealed a
signi cant increase in consumption in the App and Home groups
as compared to the Fam and Avers groups for the second, third
and fourth test trials, except for the third trial when the difference
between Fam and Home groups was non-signi cant.
12
10
8
6
4
2
0
Means Saccharine Consumption (ml)
Trials
1234
FAM APP AVERS HOME
Figure 1. Mean saccharine consumption as a function of groups (Familiar,
Home, Aversive, and Appetitive) at testing. Error bars represent SEMs
100
80
60
40
20
0
Mean Percent Activity
Trials
1234
FAM APP AVERS
Figure 2. Mean percent activity as a function of groups (Familiar, Home,
Aversive, and Appetitive) at testing. Error bars represent SEMs
Lucía Vicente, and Luis Gonzalo De la Casa
620
Figure 2 depicts mean percent activity as a function of groups
for the four test days. As can be seen in the Figure, mean percent
activity was lower in the Avers as compared to the App and Fam
groups during the rst two test trials.
The ANOVA conducted on mean percent activity collapsed
across each 60 min session revealed signi cant main effects of
Trials and Groups, F(3,63)=5.00; p<.01; η2=.19, and F(2,21)=10.01;
p<.05; η2=.49, respectively. The main effect of Trials was due to a
progressive reduction of activity across trials. The main effect of
Groups re ects the lower mean percent of activity collapsed across
trials for the Avers (Mean = 42.77 %, SEM = 5.3) as compared to
Fam and App groups (Mean = 65.57 %, SEM = 3.62, and Mean
= 61.9 %, SEM = 1.92, respectively), as revealed by post hoc
comparisons (p<.05) between groups. The 2-way interaction was
also signi cant, F(6,63)=4.11; p<.01; η2=.39. Separate repeated
measures ANOVAs with Trials as main factor for each group,
and ANOVAs between groups for each trial were conducted on
mean percent activity to identify the source of the interaction. The
analyses revealed a signi cant effect of Trials for the Avers and
the App groups, F(3,21)=4.68; p<.05; η2=.40, and F(3,21)=10.85;
p<.001; η2=.61, respectively. The effect of Trials for the Avers group
re ects the progressive increase of activity across trials, probably
due to extinction of the context’s aversive properties. The main
effect of Trials for the App group re ects a decrease of activity
across trials that could be re ecting context habituation. The effect
of Trials for the Fam group was non-signi cant, F(3,21)=2.55;
p>.08; η2=.27.
An ANOVA with Groups as main factor conducted on mean
percent activity for each trial revealed signi cant differences
between groups for the rst and the second trial, F(2,21)=16.35;
p<.001; η2=.61, and F(2,21)=17.02; p<.001; η2=.62, respectively.
Post hoc comparisons between groups (p<.05) revealed lower
percent activity in the Avers as compared to the Fam and App
groups for the rst and second trials.
Discussion
The main objective of the experiment reported in this paper
was to analyze neophobia and its habituation to a novel avor
(a saccharin solution) when it was presented in the presence of
familiar, appetitive/home, or aversive contexts. We observed that
the context did not affect neophobia on the rst day of consumption,
contrary to what has been observed in previous experiments in
which consumption of saccharin, when presented for the rst
time in the home cage, was signi cantly higher in comparison
with the case in which this avor was presented in either a new or
familiar context (De la Casa & Díaz, 2013, Exp. 2). However, in
the mentioned experiment the saccharin concentration used was
0.04%, which is notably weaker than the concentration used in the
present experiment (0.1%). It is likely that the effect of context on
neophobia was weaker when the neophobic response was more
intense.
The results related to habituation of neophobia were in
general consistent with the hypotheses proposed according to the
contextual safety theory (De la Casa, 2018), since habituation of
neophobia was signi cantly faster when the test was conducted in
the rats’ home cages and in an appetitive context in comparison
with merely familiar or aversive contexts. The reduction in
consumption when the test is conducted in the presence of the
new context has previously been interpreted in the literature as
being the result of an increase in the arousal level of the animals,
which would lead to an increase in orientation responses to the
context that are incompatible with the response of drinking (e.g.,
Honey et al., 1992). In fact, such non-associative effect could be
responsible of the absence of neophobia habituation observed in
the Fam group, since the levels of activity for such group did not
decrease across trials, indicating that four days of exposure to the
experimental context was not effective enough to successfully
reduce orientation/exploratory responses. However, such non-
associative interpretation is unable to explain the changes in
habituation of neophobia observed in the Avers group, since the
reduced consumption observed in such group was not due to an
increase in exploration of the context that is incompatible with the
drinking response (in fact, there were a signi cant decrement in
activity for the animals tested in the context associated with the
electric shocks). Also, the reduced consumption in the Avers as
compared to the App and Home groups can be interpreted as the
result of freezing induced by a process of fear conditioning to
the context in the Avers group, but the lack of differences when
comparing locomotor activity between the groups for trials 3 and 4
make such possibility unlikely.
The absence of differences in neophobia habituation between
the Fam and the Avers groups was unexpected, since we predicted
higher levels of saccharine consumption in the former as compared
to the latter. A possible explanation of this result could come from
two sources: First, the lack of effectiveness of the context exposure
to reduce the rats’ exploratory activity that could have compete
with the drinking response in the Fam group; second, the use of
mild shocks in the Avers group could have reduced the aversive
properties of the context. Both alternatives merit additional
experimental analysis (for instance, by incrementing the number
of context familiarization sessions, and/or increasing the intensity
of the aversive stimuli).
The observed increase in the speed of habituation to neophobia
(manifested as an increase in consumption of the novel avor) in
the presence of an appetitive context is a nding that is somewhat
dif cult to interpret from a non-associative perspective. This result
was observed both when the avor was presented in the home cage,
and when it appeared in a context that had received a treatment
designed to turn it into appetitive. One possible explanation for the
effect of the appetitive context on consumption comes from the
idea of energization proposed by Konorski (1967), which implies
that an appetitive Conditioned Stimulus (CS) increases the activity
of the positive motivational system, whilst aversive CSs increase
activity of the negative motivational system. Thus, similar to what
occurs in a Pavlovian-instrumental transfer experiment when the
presence of an appetitive CS increases the rate of responding
maintained by an appetitive reinforcer (e.g., Lovibond, 1983)
whilst an aversive CS increases an avoidance response (e.g.,
Rescorla y Lolordo, 1965), the presence of an appetitive context
in a neophobia situation would increase activity of the positive
motivational system, favoring the consumption of the novel avor,
whilst the opposite would occur in the aversive context.
A possible shortcoming of this study is related to recent evidence
revealing that neophobia in rats differs as a function of sex, in
such way that female rats display stronger neophobia than male
rats (Angulo & Arévalo-Romero, 2021). Therefore, the results of
our experiment should be taken cautiously since our sample only
included males. Future research on this domain should incorporate
both males and females rats in order to check for possible sex
Context Properties Modulate Flavor Neophobia Habituation
621
differences in neophobia and its habituation, and in the effect of
context on neophobia.
We will conclude with a proposal regarding possible applications
of our results to the eld of nutrition and food preferences, both for
animals and humans. Speci cally, since animals in the wild inhabit
a complex and changing environment with high pressure for
survival and continuous exposure to new and varied stimuli, some
studies have indicated that these circumstances are associated with
less food neophobia (Modlinska et al., 2015, 2020; Modlinska &
Stryjek, 2016). Conversely, farm and domestic animals, with stable
housing conditions, have less variability in their environment,
including a low exposure to different foods. The food neophobia
that usually appears when we try to implement changes in the
diet of these animals can result in growth problems or decrease
in weight, especially in animals more reactive and fearful (Neave
et al., 2018). In this vein, several studies have proposed methods
intended to decrease food neophobia, such as masking the new
food with a familiar avor (Launchbaugh et al., 1997) or a familiar
smell (van den Berg et al., 2016), presenting the new avor in
presence of other members of the group (Arrazola et al., 2020;
Modlinska & Pisula, 2018), or using taste preferences conditioning
procedures (Clouard et al., 2012). Considering our results, we can
propose effective strategies to facilitate the introduction of new
types of food in the diet of animals based on the manipulation of
the context where they are presented, since a new food in presence
of a context previously associated with aversive consequences
will increase neophobia and, therefore, hinder the eating process.
Conversely, presenting the new food in the presence of a familiar
of appetitive context will enhance the consumption of new foods.
Also, the notion of contextual control could have relevant
implications for neophobia modulation in children, since
childhood is one of the most critical periods for the formation of
dietary preferences and aversions (e.g., Cashdan, 1994; Cooke
et al., 2003). Experiences with different foods during the rst
year of life can result in the development of dietary habits that
will last for the entire lifespan (e.g., Nicklaus & Monnery-Patris,
2018). In addition, this is the period in which avor neophobia is
more intense, particularly in children between 2 and 5 years old
(Addessi et al., 2005). It has been observed that those children
with intense neophobia eat less fruits, vegetables, and proteins
(Nicklaus & Monnery-Patris, 2018). Considering that neophobia
affects between 40% and 60% of children (Brown et al., 2016),
procedures that can help to attenuate the neophobia response will
be of great relevance for the prevention of possible health problems
derived from inadequate feeding.
Whilst the present results have directly demonstrated the
effect of context on the habituation of neophobia, there is also
converging evidence from experiments with humans that have
shown the relevance of social facilitation (which can be considered
to be a more general type of context) on eating behavior (see, for
a review, Herman, 2015). Thus, for instance, people eating in a
group consume more food than when eating alone (e.g., de Castro
& de Castro, 1989; Herman, 2015), and children are more willing
to eat a particular food when they observe their caregivers or other
children tasting the same food (e.g., Addessi et al., 2005; Hendy &
Raudenbush, 2000).
Given that there is now suf cient evidence to indicate the
in uence of context on neophobia and its habituation, we can take
advantage of such knowledge to promote the consumption of a
healthy and varied diet during childhood. The principles derived
from the contextual safety hypothesis suggest that when introducing
a new food into the diet it is important to consider the context
in which it is presented, since this can play an important role in
determining whether it is accepted or rejected. Thus, if the new
food is presented in a context that has previously been associated
with an unpleasant or aversive event, then neophobia will be
more intense and its habituation slower. For instance, to pressure
or threaten children to try a new food creates an emotionally
negative context that results in an increase in the rejection of such
food (Kaar et al., 2016). According to the results obtained in our
experiments, if we wish to increase the acceptance of a new type of
food, it should be presented in an environment that has previously
been associated with pleasant experiences.
Acknowledgments
This research was funded by Agencia Estatal de Investigación
(AEI) of Spain (grant no.: PID2019-107530GB-I00/AEI/10.13039/
501100011033), and a Seville University (Spain) 2020 research
plan grant.
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... La simpleza del término, su significado y su referente empírico fácilmente asequible ha permitido que este neologismo alcance cierto nivel de popularidad en internet, de hecho, una búsqueda realizada en Google en los últimos días del año 2021 reporta 88,200 resultados. Una vez centrados en el trabajo investigativo la búsqueda de antecedentes de investigación muestra una tendencia orientada exclusivamente a la neofobia alimentaria (Alves, et al. 2021;Chagas, et al. 2019;Colín-Mar, et al 2021;Navarro-González et al. 2019;Oliveira, et al. 2021), aun con denominaciones alternas como neofobia gustativa (Navarro, 2021;Vicente & De la Casa, 2021). ...
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