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We report a study examining interspecies emotion transfer via body odors (chemosignals). Do human body odors (chemosignals) produced under emotional conditions of happiness and fear provide information that is detectable by pet dogs (Labrador and Golden retrievers)? The odor samples were collected from the axilla of male donors not involved in the main experiment. The experimental setup involved the co-presence of the dog’s owner, a stranger and the odor dispenser in a space where the dogs could move freely. There were three odor conditions [fear, happiness, and control (no sweat)] to which the dogs were assigned randomly. The dependent variables were the relevant behaviors of the dogs (e.g., approaching, interacting and gazing) directed to the three targets (owner, stranger, sweat dispenser) aside from the dogs’ stress and heart rate indicators. The results indicated with high accuracy that the dogs manifested the predicted behaviors in the three conditions. There were fewer and shorter owner directed behaviors and more stranger directed behaviors when they were in the “happy odor condition” compared to the fear odor and control conditions. In the fear odor condition, they displayed more stressful behaviors. The heart rate data in the control and happy conditions were significantly lower than in the fear condition. Our findings suggest that interspecies emotional communication is facilitated by chemosignals.
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Vol.:(0123456789)
1 3
Anim Cogn (2018) 21:67–78
https://doi.org/10.1007/s10071-017-1139-x
ORIGINAL PAPER
Interspecies transmission ofemotional information
viachemosignals: fromhumans todogs (Canis lupus familiaris)
BiagioD’Aniello1 · GünRefikSemin2· AlessandraAlterisio1· MassimoAria3·
AnnaScandurra1
Received: 10 July 2017 / Revised: 19 September 2017 / Accepted: 4 October 2017 / Published online: 7 October 2017
© Springer-Verlag GmbH Germany 2017
Keywords Dogs· Human emotional smell· Interspecies
emotional transfer· Emotional communication· Dog’s
heart rate· Dog–human bond
Introduction
Body odors constitute chemical signals that have evolved
for species-specific communication (e.g., McClintock 2000;
Stevenson 2009; Wyatt 2015). Research has shown that in
humans, chemosignals can carry compound information
ranging from genetic relatedness (Jacob etal. 2002), gender
(Penn etal. 2007), to emotional states (e.g., de Groot etal.
2012; Mujica-Parodi etal. 2009; Prehn etal. 2006; Zhou and
Chen 2009; Mutic etal. 2015) and more (see de Groot etal.
2017). The transmission of olfactory information related to
emotional states occurs without the requirement of com-
municative intent (Semin and de Groot 2013) and is below
the threshold of consciousness (Pause 2012). Nevertheless,
such transmission induces in the receiver a partial affective,
behavioral, perceptual, and neural reproduction of the state
of the sender (Semin 2007). The question we addressed here
was about interspecies transmission of emotional informa-
tion. To this end, we employed an experimental paradigm
used in our previous research (e.g., de Groot etal. 2012),
whereby the signal was human body odor that was pro-
duced while the donors were experiencing experimentally
induced emotional states (i.e., happy, fear). The receivers of
the human chemosignals were pet dogs (Labrador retrievers
and Golden retrievers). Thus, the communication paradigm
we employed exposed pet dogs to chemosignals produced by
humans and analyzed the dogs’ reactions. In the following,
we provide an overview of the relevant research to date with
dogs and then outline the current study.
Abstract We report a study examining interspecies emo-
tion transfer via body odors (chemosignals). Do human
body odors (chemosignals) produced under emotional con-
ditions of happiness and fear provide information that is
detectable by pet dogs (Labrador and Golden retrievers)?
The odor samples were collected from the axilla of male
donors not involved in the main experiment. The experi-
mental setup involved the co-presence of the dog’s owner,
a stranger and the odor dispenser in a space where the dogs
could move freely. There were three odor conditions [fear,
happiness, and control (no sweat)] to which the dogs were
assigned randomly. The dependent variables were the rel-
evant behaviors of the dogs (e.g., approaching, interacting
and gazing) directed to the three targets (owner, stranger,
sweat dispenser) aside from the dogs’ stress and heart rate
indicators. The results indicated with high accuracy that the
dogs manifested the predicted behaviors in the three condi-
tions. There were fewer and shorter owner directed behav-
iors and more stranger directed behaviors when they were
in the “happy odor condition” compared to the fear odor and
control conditions. In the fear odor condition, they displayed
more stressful behaviors. The heart rate data in the control
and happy conditions were significantly lower than in the
fear condition. Our findings suggest that interspecies emo-
tional communication is facilitated by chemosignals.
* Biagio D’Aniello
biagio.daniello@unina.it
1 Department ofBiology, University ofNaples “Federico II”,
Via Cinthia, Naples80126, Italy
2 William James Center forResearch, ISPA - Instituto
Universitário, Lisbon, Portugal
3 Department ofEconomics andStatistics, University
ofNaples “Federico II”, Naples, Italy
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... Interspecific odour communication of emotions has received increased attention in recent years [19,[40][41][42][43][44]. D'Aniello et al. [41] reported that dogs are able to recognise human emotions from body odour, as they displayed behaviours indicating stress only when being presented with human odour of fear. ...
... Interspecific odour communication of emotions has received increased attention in recent years [19,[40][41][42][43][44]. D'Aniello et al. [41] reported that dogs are able to recognise human emotions from body odour, as they displayed behaviours indicating stress only when being presented with human odour of fear. In a recent study, Sabiniewicz et al. [44] demonstrated that horses presented differential behaviours in response to human fear and non-fear odour samples, showing the ability of purely olfactory recognition of human emotions. ...
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