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Trust pervades human societies. Trust is indispensable in friendship, love, families and organizations, and plays a key role in economic exchange and politics. In the absence of trust among trading partners, market transactions break down. In the absence of trust in a country's institutions and leaders, political legitimacy breaks down. Much recent evidence indicates that trust contributes to economic, political and social success. Little is known, however, about the biological basis of trust among humans. Here we show that intranasal administration of oxytocin, a neuropeptide that plays a key role in social attachment and affiliation in non-human mammals, causes a substantial increase in trust among humans, thereby greatly increasing the benefits from social interactions. We also show that the effect of oxytocin on trust is not due to a general increase in the readiness to bear risks. On the contrary, oxytocin specifically affects an individual's willingness to accept social risks arising through interpersonal interactions. These results concur with animal research suggesting an essential role for oxytocin as a biological basis of prosocial approach behaviour.
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Oxytocin increases trust in humans
Michael Kosfeld
1
*, Markus Heinrichs
2
*, Paul J. Zak
3
, Urs Fischbacher
1
& Ernst Fehr
1,4
Trust pervades human societies
1,2
. Trust is indispensable in friend-
ship, love, families and organizations, and plays a key role in
economic exchange and politics
3
. In the absence of trust among
trading partners, market transactions break down. In the absence
of trust in a country’s institutions and leaders, political legitimacy
breaks down. Much recent evidence indicates that trust contrib-
utes to economic, political and social success
4,5
. Little is known,
however, about the biological basis of trust among humans. Here
we show that intranasal administration of oxytocin, a neuro-
peptide that plays a key role in social attachment and affiliation
in non-human mammals
6–8
, causes a substantial increase in trust
among humans, thereby greatly increasing the benefits from social
interactions. We also show that the effect of oxytocin on trust is
not due to a general increase in the readiness to bear risks. On the
contrary, oxytocin specifically affects an individual’s willingness
to accept social risks arising through interpersonal interactions.
These results concur with animal research suggesting an essential
role for oxytocin as a biological basis of prosocial approach
behaviour.
In non-human mammals, the neuropeptide oxytocin has a central
role in general behavioural regulation, particularly in positive social
interactions. Aside from its well-known physiological functions in
milk letdown and during labour, oxytocin receptors are distributed
in various brain regions associated with behaviour
9,10
, including pair
bonding, maternal care, sexual behaviour, and the ability to form
normal social attachments
6–8,11–15
. Thus, oxytocin seems to permit
animals to overcome their natural avoidance of proximity and
thereby facilitates approach behaviour. Given that oxytocin is
believed to promote social attachment and affiliation in non-
human mammals, we hypothesized that oxytocin might also pro-
mote prosocial approach behaviours
such as trust
in humans.
Recent research has shown that neuropeptides cross the blood-brain
barrier after intranasal administration
16
, providing a useful method
for studying the central nervous system effects of oxytocin in
humans
17,18
. We used a double-blind study design to compare
trusting behaviour in a group of subjects that received a single dose
of intranasal oxytocin with that of subjects in a control group that
received placebo.
We analysed the effect of exogenously administered oxytocin on
individuals’ decisions in a trust game with real monetary stakes
19–22
.
In this trust game, two subjects interacting anonymously play either
the role of an investor or a trustee (Fig. 1). First, the investor has the
option of choosing a costly trusting action by giving money to the
trustee. If the investor transfers money, the total amount available for
distribution between the two players increases but, initially, the
trustee reaps the whole increase. The trustee is then informed
about the investor’s transfer and can honour the investor’s trust by
sharing the monetary increase generated by the investor’s transfer.
Thus, if the investor gives money to the trustee and the latter shares
the proceeds of the transfer, both players end up with a higher
monetary payoff. However, the trustee also has the option of
violating the investor’s trust. As sharing the proceeds is costly for
the trustee, a selfish trustee will never honour the investor’s trust
because the investor and the trustee interact only once during the
experiment.
The investor is therefore caught in a dilemma: if he trusts and the
trustee shares, the investor increases his payoff, but he is also subject
to the risk that the trustee will abuse this trust. In the latter case, the
investor is worse off than if he had not trusted at all and, adding insult
to injury, the trustee has an unfair payoff advantage relative to the
investor. Substantial evidence exists to show that humans are averse
to such risks
22–24
. Moreover, the aversion of investors to abuse of trust
seems to have an important role across different human cultures and
social groups in the context of our game
22,25
. The investors have to
overcome their aversion against these risks in order to trust, allowing
us to address the question of whether oxytocin modulates this
trusting behaviour in humans.
LETTERS
Figure 1 | The trust game. Both subjects receive an initial endowment of 12
monetary units (MU). The investor can send 0, 4, 8 or 12 MU to the trustee.
The experimenter triples each MU the investor transfers. After the investor’s
decision is made, the trustee is informed about the investor’s transfer. Then
the trustee has the option of sending any amount between zero and his total
amount available back to the investor. For example, if the investor has sent
12 MU, the trustee possesses 48 MU (12 MU own endowment þ 36 MU
tripled transfer) and can, therefore choose any back transfer from 0 to
48 MUs. The experimenter does not triple the back transfer. The investor’s
final payoff corresponds to the initial endowment minus the transfer to the
trustee, plus the back transfer from the trustee. The trustee’s final payoff is
given by his initial endowment plus the tripled transfer of the investor,
minus the back transfer to the investor. At the end of the experiment, the
earned MU are exchanged into real money according to a publicly
announced exchange rate (see Methods). Each subject made four decisions
in the same player role while paired with four different, randomly selected
interaction partners.
1
University of Zurich, Institute for Empirical Research in Economics, Blumlisalpstrasse 10, CH-8006 Zurich, Switzerland.
2
University of Zurich, Department of Clinical Psychology
and Psychotherapy, Zurichbergstrasse 43, CH-8044 Zurich, Switzerland.
3
Center for Neuroeconomics Studies, Claremont Graduate University, Claremont, California 91711-6165,
USA.
4
Collegium Helveticum, Schmelzbergstrasse 25, CH-8092 Zurich, Switzerland.
*These authors contributed equally to this work.
Vol 435|2 June 2005|doi:10.1038/nature03701
673
© 2005 Nature Publishing Group
Our hypothesis that oxytocin increases the trusting behaviour of
investors implies that the investors in the oxytocin group (n ¼ 29)
will show higher money transfers than those in the placebo group
(n ¼ 29). In fact, our data show that oxytocin increases investors’
trust considerably. Out of the 29 subjects, 13 (45%) in the oxytocin
group showed the maximal trust level, whereas only 6 of the 29
subjects (21%) in the placebo group showed maximal trust (Fig. 2a).
In contrast, only 21% of the subjects in the oxytocin group had a trust
level below 8 monetary units (MU), but 45% of the subjects in the
control group showed such low levels of trust. These differences in
the distribution of trust result in higher average and median trust
levels for subjects given oxytocin (Table 1). The investors’ average
transfer is 17% higher in the oxytocin group (Mann-Whitney U-test;
z ¼ 21.897, P ¼ 0.029, one-sided), and the median transfer in the
oxytocin group is 10 MU, compared to a median of only 8 MU for
subjects in the placebo group.
In the trust game, the risk on the part of the investor’s is due to the
uncertainty of the trustee’s behaviour
that is, a social interaction
with a specific trustee constitutes the risk. This raises the question of
whether oxytocin helps humans to overcome a general aversion
against risks or whether oxytocin specifically affects trusting beha-
viour in social interactions. In order to answer this question, we
conducted a risk experiment in which the investor faced the same
choices as in the trust game but in which a random mechanism, not
the trustee’s decision, determined the investor’s risk. The random
mechanism in the risk experiment replicated the trustees’ decisions in
the trust experiment. Therefore, the investors faced exactly the same
risk as in the trust experiment (see Methods); however, their transfer
decisions were not embedded in a social interaction because there
were no trustees in the risk experiment.
In this risk experiment, the investors’ behaviour does not differ
between the oxytocin and the placebo groups (Table 1 and Fig. 2b).
The median transfer is 8 MU and the average transfer is 7.5 MU in
both groups (Mann-Whitney U-test; z ¼ 0.022, P ¼ 0.983; two-
sided test, n ¼ 31 in oxytocin group, n ¼ 30 in placebo group).
Moreover, there is no significant difference in a comparison of the
placebo group in the trust experiment with the oxytocin group and
the placebo group in the risk experiment (Kruskal-Wallis test;
x
2
¼ 0.533, d.f. ¼ 2, P ¼ 0.766), with identical median transfers
across groups (Table 1). However, if we add the oxytocin group in
the trust experiment to these three samples, significant differences
are observed (Kruskal-Wallis test;
x
2
¼ 8.610, d.f. ¼ 3, P ¼ 0.035),
indicating that only the investors in the oxytocin group of the trust
experiment behave differently. Thus, oxytocin increases the investors’
transfer levels in the trust experiment but not in the risk experiment.
This finding is illustrated by a comparison of Figs 2a and b, which
show that only 10% of the subjects with oxytocin choose the maximal
transfer level in the risk experiment, whereas 45% choose the
maximal level in the trust experiment. Therefore, the differences
between the oxytocin group in the trust experiment and the oxytocin
group in the risk experiment are highly significant (Mann-Whitney
U-test; z ¼ 22.563, P ¼ 0.010, two-sided), suggesting that oxytocin
specifically affects trust in interpersonal interactions.
The risk experiment constitutes a powerful control for the effects
of oxytocin on trusting behaviour because everything is kept con-
stant relative to the trust experiment, except that the investors’ risk in
the risk experiment is not generated through a social interaction.
Specifically, all the indirect effects of oxytocin on the state of a
subject, such as possible effects on mood or calmness, would be
present in both the trust and the risk experiment. Therefore, these
potential indirect effects of oxytocin cannot be responsible for the
effect of oxytocin on trusting behaviour. Moreover, in order to
provide an additional control for non-specific effects that might be
associated with oxytocin administration, we explicitly measured
mood and calmness before substance administration and 50 min
after administration (but before subjects played the trust or the risk
game). We used a questionnaire suitable for repeated measures
within short periods of time, one that is widely used in neuropharma-
cological studies in humans
26
and correlates with physiological
measures
17
. There were no statistical differences in the levels of
mood and calmness before and after the administration of oxytocin
in either the trust or the risk experiment. (Trust experiment:
z ¼ 21.541, P ¼ 0.123 for calmness; z ¼ 1.452, P ¼ 0.146 for
mood; n ¼ 29. Risk experiment: z ¼ 0.620, P ¼ 0.535 for calmness;
z ¼ 20.841, P ¼ 0.400 for mood; n ¼ 31; two-sided Wilcoxon
signed rank tests.) This provides further support for our conclusion
Figure 2 | Transfers in the trust and the risk experiment. Each observation
represents the average transfer amount (in MU) over four transfer decisions
per investor. a, Relative frequency of investors’ average transfers in oxytocin
(filled bars) and placebo (open bars) groups in the trust experiment
(n ¼ 58). Subjects given oxytocin show significantly higher transfer levels.
b, Relative frequency of investors’ average transfers in oxytocin (filled bars)
and placebo (open bars) groups in the risk experiment (n ¼ 61). Subjects in
the oxytocin and the placebo group show statistically identical transfer
levels.
Table 1 | Median and average transfer behaviour of investors
Trust experiment Risk experiment
Oxytocin group Placebo group Oxytocin group Placebo group
Mean average transfer (MU) 9.6 8.1 7.5 7.5
Median average transfer (MU) 10 8 8 8
Standard deviation of transfers (MU) 2.8 3.1 3.3 3.4
Number of observations 29 29 31 30
LETTERS NATURE|Vol 435|2 June 2005
674
© 2005 Nature Publishing Group
that the effect of oxytocin on human trust is not caused by non-
specific, psychotropic effects of oxytocin.
What mechanisms might be involved in generating the effect of
oxytocin on trusting behaviour? One possibility is that oxytocin
causes a general increase in prosocial inclinations. This implies that
oxytocin should affect not only the prosocial behaviour of the
investors but also that of the trustees. We would therefore predict
that those trustees who are given oxytocin should make higher back
transfers at any given level than the trustees who received placebo.
However, trustees given oxytocin do not show more trustworthy
behaviour (Fig. 3). At every positive transfer level (4, 8 or 12 MU),
their back transfers are statistically indistinguishable from those of
placebo trustees (Mann Whitney U-tests; P . 0.243, two-sided tests
for each positive transfer level). Thus, oxytocin does not increase
the general inclination to behave prosocially. Rather, oxytocin
specifically affects the trusting behaviour of investors.
We hypothesize that the differing effect of oxytocin on the
behaviour of investors and trustees is related to the fact that investors
and trustees face rather different situations. Specifically, investors
have to make the first step; they have to ‘approach the trustee by
transferring money. In contrast, the trustees can condition their
behaviour on the basis of the investors’ actions. Thus, the psychology
of trust is important for investors, whereas the psychology of strong
reciprocity
27
is relevant for trustees. The fact that oxytocin affects
subjects’ approach or trust behaviour, but not their degree of
reciprocity, is in agreement with animal studies. There is substantial
evidence that oxytocin promotes prosocial approach behaviour by
inhibiting defensive behaviours
6,13
, but there is no evidence that
oxytocin affects reciprocity in animals.
A second mechanism behind the effect of oxytocin on trust could
be based on subjects’ beliefs. Oxytocin might render subjects more
optimistic about the likelihood of a good outcome. In order to
address this question, we measured the investor’s subjective expec-
tation about the trustee’s back transfer after every transfer decision.
A Mann-Whitney U-test indicates that these expectations do not
differ significantly between oxytocin and placebo groups at every
feasible positive transfer level (P . 0.357, two-sided tests at transfer
levels of 4, 8 or 12 MU). Thus, the investors given oxytocin show
more trusting behaviour but do not hold significantly different
beliefs about the trustworthiness of others. Moreover, oxytocin
does not affect investors’ beliefs about the likelihood of a good
outcome in the risk experiment (P . 0.128, two-sided Mann
Whitney U-tests for transfer levels of 4, 8 or 12 MU).
Finally, there is the possibility that oxytocin helps subjects to
overcome their betrayal aversion in social interactions. This expla-
nation is consistent with the differing effects of oxytocin across the
trust and the risk experiments, and is further supported by the fact
that investors faced a considerable betrayal risk. An increase in the
transfer level from 4 or 8 MU to 12 MU decreased the investor’s
average payoff slightly, whereas it increased the objective risk of very
low back transfers by the trustee. However, betrayal aversion alone
cannot explain why investors given oxytocin make higher transfers in
the trust experiment compared with the risk experiment, because
betrayal is impossible in the risk experiment. The higher transfers in
the trust experiment can be reconciled with betrayal aversion if one
acknowledges that investors’ behaviour in the trust experiment is also
likely to be driven by the motive to increase the available amount for
distribution between the two players
28
. As this motive cannot operate
in the risk experiment, it can only increase transfers levels in the trust
experiment. Our interpretation of oxytocins effect on trust in terms
of betrayal aversion may be seen in the light of animal studies
indicating that increased availability of oxytocin in the central
nervous system facilitates approach behaviour, by linking the over-
coming of social avoidance with the activation of brain circuits
implicated in reward (for example, the nucleus accumbens)
12,15
.
The ubiquity of trusting behaviour is perhaps one of the dis-
tinguishing features of the human species. An element of trust
characterizes almost all human social interactions. Here we have
sought to examine the effect of oxytocin on trust in humans.
Research in non-human mammals suggests that oxytocin has a key
role in social attachment and affiliation. We find that intranasal
administration of oxytocin causes a substantial increase in trusting
behaviour. Subjects given oxytocin seem better able to overcome
trust obstacles such as betrayal aversion. Of course, this finding could
be misused to induce trusting behaviours that selfish actors sub-
sequently exploit. However, our findings may also have positive
clinical implications for patients with mental disorders that are
associated with social dysfunctions (for example, social phobia or
autism). In particular, social phobia ranks as the third most common
mental health disorder and is characterized by marked social deficits,
including persistent fear and avoidance of social interactions. Thus,
our results might lead to fertile research on the role of oxytocin in
several mental health disorders with major public health significance.
METHODS
Subjects. A total of 194 healthy male students (mean age ^ s.d., 22.0 ^ 3.4 yr)
from different universities in Zurich participated in the study. The trust
experiment had 128 participants, and 66 subjects participated in the risk
experiment. Exclusion criteria for participation were significant medical or
psychiatric illness, medication, smoking more than 15 cigarettes per day, and
drug or alcohol abuse. Subjects were instructed to abstain from food and drink
(other than water) for 2 h before the experiment, and from alcohol, smoking and
caffeine for 24 h before the experiment. Participants were informed at the time of
recruitment that the experiment would evaluate the effects of a hormone on
decision making. In total, 16 individuals out of the original sample of 194 were
excluded because of incorrect substance administration (7 in the trust experi-
ment, 5 in the risk experiment) or their stated disbelief that the opponent in the
trust game was actually a human being (4 participants). The study protocol was
approved by the ethics committee of the University of Zurich. All subjects gave
written, informed consent before participation.
Substance administration. Subjects received a single intranasal dose of 24 IU
oxytocin (Syntocinon-Spray, Novartis; 3 puffs per nostril, each with 4 IU
oxytocin) or placebo 50 min before the start of the trust or the risk experiment.
Subjects were randomly assigned to the oxytocin or placebo group (double-
blind, placebo-controlled study design). In order to avoid any subjective
substance effects (for example, olfactory effects) other than those caused by
oxytocin, the placebo contained all inactive ingredients except for the
neuropeptide.
Behavioural experiment and questionnaires. After substance administration,
Figure 3 | Average back transfer of trustees to their investors. The graph
shows the average back transfer by trustees for different levels of investor
transfer in the oxytocin and placebo groups. The dotted line shows the level
of the back transfer necessary to achieve payoff equality between the investor
and the trustee. The dashed line shows a level of back transfer equal to the
investor’s transfer to the trustee. The trustees’ back transfers are on average
slightly higher than the amount sent by the investor. Trustees in both
treatment groups make higher back transfers in response to higher original
investor transfer levels. However, there is no statistically significant
difference in back transfers between subjects in the oxytocin and the placebo
groups.
NATURE|Vol 435|2 June 2005 LETTERS
675
© 2005 Nature Publishing Group
subjects completed questionnaires on a computer to measure demographic
items and psychological characteristics. Owing to the crucial role of the social
environment in triggering behavioural effects of oxytocin (as shown in animal
research)
13,29
, subjects were asked to wait in the rest area while the next part of the
experiment was prepared. During this 5-min waiting period, subjects were seated
at different tables. Subjects at the same table could talk to each other, but at the
beginning of the experiment they were informed that they would not be
interacting with those subjects who sat at the same table. When subjects re-
entered the laboratory for both experiments, they received written instructions
(available from the authors on request) explaining the payoff structure of the
experiment and the private payment procedure at the end of the experiment.
Subjects were randomly and anonymously assigned to the role of investor or
trustee in the trust experiment, and did not know the identity of the persons with
whom they were matched. After subjects had read the instructions in each
experiment, we checked whether they understood the payoff structure by means
of several hypothetical examples. All subjects (with one exception) answered the
control questions correctly. One subject did not answer the control questions
correctly and was excluded from the data set (this subject also did not apply the
substance correctly). In addition, subjects received an oral summary of the
instructions.
Each subject in the trust experiment made four decisions in the same player
role while paired with different, randomly selected interaction partners. No pair
of subjects interacted twice. Subjects in the role of the investor received no
feedback about the trustee’s decision between the different interactions. After
every transfer decision, each investor was asked about his belief with regard to
the expected back transfer from the trustee. Notably, trust levels were statistically
constant across the four decisions. There is no time trend in investors’ decisions
in either the oxytocin or the placebo group. In the risk experiment, everything
was identical to the trust experiment, except that all subjects played the role of an
investor who could transfer 0, 4, 8, or 12 MU into a project rather than to a
trustee. In particular, an investor’s payoff risk (that is, the distribution of payoffs)
in the risk experiment was identical to that in the trust experiment at any feasible
transfer level.
To measure alterations in the psychological state of subjects throughout the
course of the experiment, we assessed their mood and calmness at the beginning
of the experiment (before substance administration) and immediately before the
trust experiment or the risk experiment, by means of a suitable questionnaire
26
.
All decisions in the experiments and the answers to the questionnaires were
entered on a computer using z-Tree software
30
. Subjects received a flat fee of 80
Swiss francs for participation in the experiment; each MU earned in the trust and
the risk experiment was worth 0.40 Swiss francs.
Received 20 April; accepted 5 May 2005.
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Acknowledgements This paper is part of the Research Priority Program
‘Foundations of Human Social Behaviour
Altruism versus Egoism’ at the
University of Zurich. Financial support from the MacArthur Foundation
(Network on Economic Environments and the Evolution of Individual Preferences
and Social Norms) and the Cogito Foundation is gratefully acknowledged. M.H.
also acknowledges support from the Swiss National Science Foundation. We
thank F. Heusi, A. Enzler, S. Gilomen, E. Go
¨
tz, M. Koenigsberg, K. Korsunsky,
S. Krammer, S. Lauber, P. Obrist-Rybar, M. Schellhammer, B. Studer, R. Stu¨nzi
and M. Trottmann for research assistance.
Author Information Reprints and permissions information is available at
npg.nature.com/reprintsandpermissions. The authors declare no competing
financial interests. Correspondence and requests for materials should be
addressed to E.F. (efehr@iew.unizh.ch) and M.H.
(m.heinrichs@psychologie.unizh.ch).
LETTERS NATURE|Vol 435|2 June 2005
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© 2005 Nature Publishing Group
Corrigendum
Due to a printing error Figure 2a in the original publication of Kosfeld M., Heinrichs M.,
Zak P.J., Fischbacher U. & Fehr E., “Oxytocin increases trust in humans, Nature 435, 2005,
673-676 contains a mistake. Three observations are missing. All of them are in the placebo
group (open bars) at an average transfer of 10. All statistical tests in the paper were done
including these observations.
Figure 2a Transfers in the Trust Experiment (Corrected).
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
0.50
0123456789101112
Average transfer per investor(MU)
Relative frequency
Placebo group Oxytocin group
... These preclinical observations have resulted in numerous human studies. For instance, healthy volunteers administered intranasal OT exhibit increased trust (Kosfeld et al., 2005) and ability to interpret social cues (DeWall et al., 2014), improved social recognition (Domes et al., 2007, Guastella andMacLeod, 2012) and partner bonding (Ditzen et al., 2009, Scheele et al., 2013. ...
... Other preclinical studies investigating OT's effect on social interaction and cognition followed and positive behavioural effects were demonstrated. Together with a prominent clinical study in 2005 showing intranasal OT increased trust (Kosfeld et al., 2005), this led to a flurry of clinical trials focused on utilising OT as a potential treatment for socio-behavioural deficits in man. ...
... The focus on OT's ability to modulate social behaviour has strongly focused on its prosocial effects, yet accumulating evidence A recent attempt to replicate the infamous OT increases trust study by Kosfeld et al. (2005) further bolsters the social salience theory. In his study, Kosfeld et al. (2005) seated participants together for 5 minutes allowing for brief social contact but prior to their knowledge that they were to participate in a trust based game, and found that subjects administered intranasal oxytocin were willing to trust a stranger and took more risks. ...
Article
Oxytocin (OT), an endogenous hormone and neuropeptide has been highlighted for its therapeutic potential to modulate socio-behavioural deficits. However, OT’s high molecular weight and hydrophilicity limits the extent of central nervous system (CNS) brain penetration, highlighting a need to improve OT brain delivery. An alternative popular route of drug delivery is intranasal administration, which allows small peptides to bypass the blood brain barrier (BBB) and access the brain more directly. Yet, the degree of OT brain penetration remains controversial and requires further improvement. As such, this thesis examined the modulation of CNS OT penetration by use of intranasal OT alone and when conjugated to a novel cell penetrating peptide: glycosaminoglycan (GAG)-binding enhanced transduction (GET; P21-LK15- 8R), producing OT-GET, and its ability to affect locomotor activity and social behaviour in rats. In vitro assays were established to determine OT-GET’s bioactivity, ability to improve OT transduction across a nasal epithelial cell monolayer and potential cytotoxicity. Using a calcium fluorimetry assay, OT-GET induced robust [Ca2+]i transients in OTR expressing Hs 578t breast cancer cells. Subsequent examination of OT-GET in a cell permeability assay using immortalised nasal epithelial cells RPMI 2650 saw an increased rate of OT delivery across the monolayer compared to OT alone. Only the highest GET concentration produced cytotoxicity (on cell viability) effects, which emphasised the need to identify an ideal peptide conjugation ratio in order to achieve desired effects without concomitant toxicity. In rats, subcutaneous OT (0.1mg/kg) reversed phencyclidine (PCP)-induced hyperactivity. Intranasal OT (100μg) showed slight effect, where cumulative ambulatory counts in the 30 minutes post-PCP was not significantly different to rats pre-treated with subcutaneous OT, although counts remained higher than saline treated animals. The same dose of intranasal OT increased the time spent by weight-matched rat pairs in prosocial body sniffing. Interestingly, a separate quantification of OT levels in the olfactory bulb revealed that OT-GET treated animals had a significant increase in OT compared to OT treated animals. Overall, OT-GET improved OT permeation across a nasal cell monolayer in vitro and improved brain penetration (olfactory bulb) in vivo compared to OT alone. Intranasal OT-GET did not produce changes in rats’ social behaviour, which may be due to OT receptor (OTR) desensitisation.
... Ever since the famous landmark studies of intranasal OT administration by Kosfeld and colleagues [80] and Kirsch and colleagues [81], various forms of OT treatment (intranasally, infusion or endogenously-evoked release) have been applied to various behavioral paradigms, as well as many psychiatric illnesses and diseases, both in rodents, monkeys, and humans [24,[82][83][84][85][86][87][88][89][90][91][92][93][94][95][96]. It is important to note, however, that some skepticism about the efficacy of intranasal OT delivery remains [33,97]. ...
Article
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The prosocial neuropeptide oxytocin is being developed as a potential treatment for various neuropsychiatric disorders including autism spectrum disorder (ASD). Early studies using intranasal oxytocin in patients with ASD yielded encouraging results and for some time, scientists and affected families placed high hopes on the use of intranasal oxytocin for behavioral therapy in ASD. However, a recent Phase III trial obtained negative results using intranasal oxytocin for the treatment of behavioral symptoms in children with ASD. Given the frequently observed autism-like behavioral phenotypes in Prader-Willi and Schaaf-Yang syndromes, it is unclear whether oxytocin treatment represents a viable option to treat behavioral symptoms in these diseases. Here we review the latest findings on intranasal OT treatment, Prader-Willi and Schaaf-Yang syndromes, and propose novel research strategies for tailored oxytocin-based therapies for affected individuals. Finally, we propose the critical period theory, which could explain why oxytocin-based treatment seems to be most efficient in infants, but not adolescents.
... En particulier, lorsque l'individu partage de bons moments en compagnie d'un être cher, le système de détresse de séparation PANIC se trouve apaisé, et l'activation du système de don de soins CARE produit des comportements d'affiliations ; ensemble, ces systèmes encensent les liens sociaux.La libération d'ocytocine régule la production du noyau moteur dorsal du vague, en maintenant la production à des niveaux optimaux pour soutenir l'homéostasie et assurer une fonction « anti-stress ». De façon schématique, plus un sujet est stressé, plus son niveau d'ocytocine est bas(Heinrichs et al., 2003) et plus les niveaux d'ocytocine sont hauts, plus le sujet présente des attitudes et des comportements prosociaux(Feldman, 2012;Kosfeld et al., 2005). Dans ce contexte, le CVD encourage les activités anaboliques liées à la restauration, à la conservation de l'énergie corporelle et au repos des organes vitaux. ...
Thesis
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Ce projet de thèse vise à étudier la pertinence d’utiliser la médiation équine en thérapie, auprès de personnes ayant des troubles addictifs. Dans un premier temps, il s’agira d’étudier l’influence du style d’attachement des patients sur leur niveau d’autonomie ; en s’appuyant sur des modèles théoriques tels que la théorie de l’attachement (Bowlby, 1969-82 ; Hazan, 1987) et la théorie de la motivation autonome (Decy et Ryan, 2000). Dans un deuxième temps, l’objectif sera d’explorer, de décrire et d’évaluer les processus à l’œuvre durant l’intervention à visée thérapeutique avec le cheval. Cette recherche s’inscrit dans le cadre de la compréhension et de l’évaluation des interventions complexes, axe fort de recherche du laboratoire APEMAC. Le questionnement principal de ce projet de thèse est d'interroger la place de la théorie de l’attachement dans les interventions en psychologie de la santé, notamment dans les programmes de prévention de la reconsommation et de la rechute. Quels liens la motivation et l’attachement entretiennent-ils ? En quoi les troubles de l’attachement peuvent-ils entraver le processus de guérison et la tenue de l’abstinence chez ces patients ? L’utilisation du cheval en thérapie peut-elle permettre d’augmenter le sentiment de sécurité interne des personnes et favoriser le développement de leurs compétences d’auto-régulation et de la motivation autonome ? En somme, peut-on augmenter l’autonomie des patients en leur proposant une intervention qui cible les troubles de l’attachement ? Le recueil des données sera réalisé au Centre de Soins de Suite et de Réadaptation en Addictologie « la Fontenelle ». Tout au long de cette recherche, nous prévoyons d’effectuer différentes évaluations quantitatives à l’aide d’outils psychométriques. Nous utiliserons également des méthodes qualitatives en réalisant des entretiens cliniques.
... Evidence of its pro-social effects has created a great interest in the possibility of using it as a treatment to improve social dysfunction that is evident in some psychiatric disorders, e.g., schizophrenia and autism [19]. Some studies suggested oxytocin to be related to empathy [20], while other reports focused on the role of oxytocin in the regulation and promotion of prosocial behavior [21]. Certain polymorphisms on the oxytocin receptor gene were recently associated with poor social cognition in children with ADHD and those at risk for CD [22,23]. ...
Article
Full-text available
Background Conduct disorder (CD) is a serious and common psychiatric disorder affecting children and adolescents. “Callous-unemotional traits” is a new specifier added to the diagnosis of CD in the DSM-5. The new specifier is thought to be associated with more severity and higher genetic load. Oxytocin is known to be related to interpersonal sympathy and social affection, and so its deficiency might be related to unemotionality. This work aims to explore the levels of serum oxytocin in adolescents with CD associated with callous-unemotional (CU) traits as compared to healthy control subjects. Twenty patients aged 12–18 years and 20 controls of the same age range were recruited. An Arabic-translated and validated version of Mini International Neuropsychiatric Interview for kids (MINI-kid) was used to confirm the diagnosis. The Youth Psychopathic Inventory-short version (YPI-short version) and the Inventory of Callous-Unemotional Traits (ICU), both parent and self-reports, were all translated into Arabic and validated by the authors and used to evaluate the sample. Evaluation of serum oxytocin level using ELISA technique was done. Results After statistical adjustment for differences in socioeconomic status, an adolescent with CD associated with CU traits showed low levels of serum oxytocin level as compared with the control group. Serum oxytocin levels were negatively correlated in a statistically significant degree with the unemotional, the callousness, and the uncaring subscores of ICU—self-report. Conclusions Low levels of serum oxytocin might play a potential role as a biomarker for CU traits and CD severity in adolescents with CD.
... Furthermore, frequency of prosocial behavior towards other and experience of prosocial behavior from others has also been shown to be a protective predictor for mental health processes (Haroz et al., 2013;Raposa et al., 2016). Moreover, feelings of trust also form a crucial component of social cohesion as it forms the basis of social capital, along with social engagement and participation which is also a foundational aspect of social cohesion (Kosfeld et al., 2005;Putnam, 1993). Trust is seen as an individual's feeling or expectation of probability or predictability of behavior of others behavior as well as the intentions of the individual (Glaeser et al., 2000). ...
Article
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During the first 2 years of the COVID-19 pandemic, empirical efforts in the psychological sciences have been unequivocally focused on understanding the psychosocial impact on resilience and vulnerability. While current empirical work is guided by different existing theoretical models of resilience and vulnerability, the emerging datasets have also pointed to a necessity for an update of these models. Due to the unique features and developments specific to the current pandemic such as the occurrence of repeated collective stressors of varying durations, in the current position paper, we introduce the Wither or Thrive model of Resilience (With:Resilience). It integrates key aspects of prevailing psychological resilience frameworks within the context of the COVID-19 pandemic, and extends them by (1) moving away from single scale approaches towards a higher-order latent expression of resilience and vulnerability incorporating also non-clinical mental health markers, (2) proposing different trajectories of resilience-vulnerability emerging across repeated stressors over long periods of time, and (3) by incorporating multiple influencing factors including aspects of the socio-economic concept of social cohesion as well as separate mediating processing mechanisms. We propose that With:Resilience will enable a more nuanced approach and appropriate analytical investigation of the vast incoming data on mental health and resilience during the COVID-19 pandemic, and we suggest some concrete methodological approaches. This framework will assist in the development of actionable public health guidelines for society in the present and future pandemic contexts as well as aid policy making and the interventional sciences aimed at protecting the most vulnerable amongst us.
... For example, research has found that the act of hugging, a touching behavior, has the power of increasing oxytocin levels within individuals (Light et al., 2005). Also known as "the love hormone," oxytocin makes people feel good and has positive effects, such as reducing anxiety and increasing perceived trust (Bethlehem et al., 2014;Kosfeld et al., 2005). Additionally, touching behaviors facilitate the release of dopamine, which underlie the experience of sensory pleasure (e.g., Keltner, 2009). ...
Conference Paper
The present study examines how supportive tactile communication impacts evaluations of esteem support messages containing high emotion-focused (HEF) or high problem-focused (HPF) content. A 2 (verbal content; i.e., HEF or HPF) by 2 (nonverbal content; i.e., presence or absence of supportive tactile communication) quasi-experiment was conducted to test for main and interactional effects of messages on relational outcomes. Participants (N = 409) were randomly assigned to watch one of four videotaped esteem support interactions between friends in which verbal content and nonverbal behavior were manipulated. Then, participants rated perceived relational outcome items (i.e., relational satisfaction, closeness, liking). Results from the experiment revealed that HEF conditions were rated significantly higher on perceptions of satisfaction, closeness, and liking compared to the HPF conditions. Additionally, supportive tactile communication conditions were rated significantly higher on perceptions of satisfaction, closeness, and liking compared to conditions with no supportive tactile communication. The 2-way interactions also revealed that the inclusion of supportive tactile communication with HEF and HPF content, increased perceptions of satisfaction, closeness, and liking beyond verbal content alone. Theoretical and pragmatic implications, in addition to limitations and future avenues for research, are also discussed.
... For example, in a wide range of species, including many primates, TE promotes sexual activity and sex-related aggression [9,11] but is downregulated in monogamous as well as paternal males [6,8,[12][13][14][15][16]. By contrast, OT facilitates pair-bonding, monogamy and paternal care [6,8,14,16]. Beyond reproduction, TE contributes to aggression, competition and status-seeking behaviours [17][18][19], whereas OT promotes affiliative behaviours such as trust [20], empathy [21] and mentalizing [22,23]. ...
Article
Social stimuli, like faces, and sexual stimuli, like genitalia, spontaneously attract visual attention in both human and non-human primates. Social orienting behaviour is thought to be modulated by neuropeptides as well as sex hormones. Using a free viewing task in which paired images of monkey faces and anogenital regions were presented simultaneously, we found that male rhesus macaques overwhelmingly preferred to view images of anogenital regions over faces. They were more likely to make an initial gaze shift towards, and spent more time viewing, anogenital regions compared with faces, and this preference was accompanied by relatively constricted pupils. On face images, monkeys mostly fixated on the forehead and eyes. These viewing preferences were found for images of both males and females. Both oxytocin (OT), a neuropeptide linked to social bonding and affiliation, and testosterone (TE), a sex hormone implicated in mating and aggression, amplified the pre-existing orienting bias for female genitalia over female faces; neither treatment altered the viewing preference for male anogenital regions over male faces. Testosterone but not OT increased the probability of monkeys making the first gaze shift towards female anogenital rather than face pictures, with the strongest effects on anogenital images of young and unfamiliar females. Finally, both OT and TE promoted viewing of the forehead region of both female and male faces, which display sexual skins, but decreased the relative salience of the eyes of older males. Together, these results invite the hypothesis that both OT and TE regulate reproductive behaviours by acting as a gain control on the visual orienting network to increase attention to mating-relevant signals in the environment. This article is part of the theme issue ‘Interplays between oxytocin and other neuromodulators in shaping complex social behaviours’.
Article
The difficulty in resurrecting inter-ethnic cooperation in the aftermath of violence and genocide is one of the biggest challenges facing post-conflict societies. Using experimental data from post-genocide Rwanda and Burundi, this paper shows that an unwarranted tendency to blame others for negative outcomes is a behavioural barrier that makes reconciliation difficult. We show that individuals systematically (and mistakenly) blame accidental negative shocks (noise) to the deliberate intent of individuals (bias). This “victimhood bias” wherein individuals ascribe noise to bias is much larger for (a) individuals for whom ethnic identity is salient; (b) for those who have had greater exposure to inter-ethnic violence. Further, we observe that both inter-ethnic contact and economic development are associated with a decline in this victimhood bias. Finally, those with a lower victimhood bias are more likely to behave cooperatively in inter-ethnic relationships. Our results suggest that insurance agreements that limit negative shocks and reduce noise, can encourage reconciliation by mitigating feelings of victimhood.
Article
Social behaviour is an essential component of human life and deficits in social function are seen across multiple psychiatric conditions with high morbidity. However, there are currently no FDA-approved treatments for social dysfunction. Since social cognition and behaviour rely on multiple signalling processes acting in concert across various neural networks, treatments aimed at social function may inherently require a combinatorial approach. Here, we describe the social neurobiology of the oxytocin and endocannabinoid signalling systems as well as translational evidence for their use in treating symptoms in the social domain. We leverage this systems neurobiology to propose a network-based framework that involves pharmacology, psychotherapy, non-invasive brain stimulation and social skills training to combinatorially target trans-diagnostic social impairment. Lastly, we discuss the combined use of oxytocin and endocannabinoids within our proposed framework as an illustrative strategy to treat specific aspects of social function. Using this framework provides a roadmap for actionable treatment strategies for neuropsychiatric social impairment. This article is part of the theme issue ‘Interplays between oxytocin and other neuromodulators in shaping complex social behaviours’.
Article
Trust involves a willingness to accept vulnerability, comprised of the risk of being worse off than by not trusting, the risk of being worse off than the trusted party (disadvantageous inequality), and the risk of being betrayed by the trusted party. We examine how people’s status, focusing on sex, race, age and religion, affects their willingness to accept these three risks. We experimentally measure people’s willingness to accept risk in a decision problem, a risky dictator game, and a trust game, and compare responses across games. Groups typically considered having lower status in the US – women, minorities, young adults and non-Protestants – are averse to disadvantageous inequality while higher status groups – men, Caucasians, middle-aged people and Protestants – dislike being betrayed.
Article
A menu of paired lottery choices is structured so that the crossover point to the high-risk lottery can be used to infer the degree of risk aversion. With normal laboratory payoffs of several dollars, most subjects are risk averse and few are risk loving. Scaling up all payoffs by factors of twenty, fifty, and ninety makes little difference when the high payoffs are hypothetical. In contrast, subjects become sharply more risk averse when the high payoffs are actually paid in cash. A hybrid "power/expo" utility function with increasing relative and decreasing absolute risk aversion nicely replicates the data patterns over this range of payoffs from several dollars to several hundred dollars.
Article
During breastfeeding or suckling, maternal oxytocin levels are raised by somatosensory stimulation. Oxytocin may, however, also be released by nonnoxious stimuli such as touch, warm temperature etc. in plasma and in cerebrospinal fluid. Consequently, oxytocin may be involved in physiological and behavioral effects induced by social interaction in a more general context. In both male and female rats oxytocin exerts potent physiological antistress effects. If daily oxytocin injections are repeated over a 5-day period, blood pressure is decreased by 10–20 mmHg, the withdrawal latency to heat stimuli is prolonged, cortisol levels are decreased and insulin and cholecystokinin levels are increased. These effects last from 1 to several weeks after the last injection. After repeated oxytocin treatment weight gain may be promoted and the healing rate of wounds increased. Most behavioral and physiological effects induced by oxytocin can be blocked by oxytocin antagonists. In contrast, the antistress effects can not, suggesting that unidentified oxytocin receptors may exist. The prolonged latency in the tail-flick test can be temporarily reversed by administration of naloxone, suggesting that endogenous opioid activity has been increased by the oxytocin injections. In contrast, the long-term lowering of blood pressure and of cortisol levels as well as the sedative effects of oxytocin have been found to be related to an increased activity of central α2-adrenoceptors. Positive social interactions have been related to health-promoting effects. Oxytocin released in response to social stimuli may be part of a neuroendocrine substrate which underlies the benefits of positive social experiences. Such processes may in addition explain the health-promoting effects of certain alternative therapies. Because of the special properties of oxytocin, including the fact that it can become conditioned to psychological state or imagery, oxytocin may also mediate the benefits attributed to therapies such as hypnosis or meditation. © 1998 Elsevier Science Ltd. All rights reserved.
Article
The neuropeptide oxytocin has been implicated in the mediation of several forms of affiliative behavior including parental care, grooming, and sex behavior. Here we demonstrate that species from the genus Microtus (voles) selected for differences in social affiliation show contrasting patterns of oxytocin receptor expression in brain. By in vitro receptor autoradiography with an iodinated oxytocin analogue, specific binding to brain oxytocin receptors was observed in both the monogamous prairie vole (Microtus ochrogaster) and the polygamous montane vole (Microtus montanus). In the prairie vole, oxytocin receptor density was highest in the prelimbic cortex, bed nucleus of the stria terminalis, nucleus accumbens, midline nuclei of the thalamus, and the lateral aspects of the amygdala. These brain areas showed little binding in the montane vole, in which oxytocin receptors were localized to the lateral septum, ventromedial nucleus of the hypothalamus, and cortical nucleus of the amygdala. Similar differences in brain oxytocin receptor distribution were observed in two additional species, the monogamous pine vole (Microtus pinetorum) and the polygamous meadow vole (Microtus pennsylvanicus). Receptor distributions for two other neurotransmitter systems implicated in the mediation of social behavior, benzodiazepines, and mu-opioids did not show comparable species differences. Furthermore, in the montane vole, which shows little affiliative behavior except during the postpartum period, brain oxytocin receptor distribution changed within 24 hr of parturition, concurrent with the onset of maternal behavior. We suggest that variable expression of the oxytocin receptor in brain may be an important mechanism in evolution of species-typical differences in social bonding and affiliative behavior.