- Tous
les articles sur la contagion du
bâillement
- All
articles about contagious
yawning
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- The authors tested susceptibility to
contagious itching, laughter, and yawning in 55
children with autism spectrum disorder (ASD),
ages 8&endash;14, and 106 typically develop- ing
(TD) children, ages 5&endash;14. Children with
ASD were less likely to yawn or laugh con-
tagiously compared with TD peers, but showed
increased susceptibility to contagious itching,
under naturalistic conditions. Contagious
yawning and laughter were posi- tively
correlated with emotional empathy in the TD
group. In contrast, contagious itching showed no
relationship to empathy, and was positively
correlated with autism symptom severity in the
ASD group. The authors explore the implications
of these findings in terms of psychological
theories about ASD.
-
-
- Les auteurs ont testé la
sensibilité à la contagion des
démangeaisons, du rire et du
bâillement chez 55 enfants atteints de
troubles du spectre autistique (TSA),
âgés de 8 à 14 ans, et 106
enfants en développement normal (TD),
âgés de 5 à 14 ans. Les
enfants atteints de TSA étaient moins
susceptibles de bâiller ou de rire de
façon contagieuse que leurs pairs TD,
mais montraient une susceptibilité accrue
à la contagion des démangeaisons,
dans des conditions naturalles. Les
bâillements contagieux et les rires
étaient positivement
corrélés à l'empathie
émotionnelle dans le groupe TD. En
revanche, la contagion des démangeaisons
n'a montré aucune relation avec
l'empathie mais était positivement
corrélées à la
gravité des symptômes de l'autisme
dans le groupe TSA. Les auteurs explorent les
implications de ces résultats en termes
de théories psychologiques sur les TSA.
- INTRODUCTION
-
- Autism spectrum disorder (ASD) is
characterized by restricted and repetitive
behaviors and pervasive difficulties in social
cogni- tion and communication (American
Psychiatric Association, 2013), as well as
atypical development of empathy (Baron-Cohen
& Wheelwright, 2004; Schulte-Ru_ther et al.,
2014). Theories of em- bodied cognition
speculate that the means by which we develop
empathy is by mentally simulating the
experiences of others, as we embody their
actions. One type of simulation that occurs
early in development is demonstrated by the
phenomenon of contagion&emdash; the transfer of
behaviors (facial expression, tone of voice,
body posture) from one person to another without
conscious attribution (Dimberg, Thunberg, &
Elmehed, 2000; Meltzoff & Moore, 1989); for
example, when a newborn baby cries at the sound
of another baby crying (Simner, 1971). Sharing
motor&emdash;and thus, neural&emdash;rep-
resentations with social partners may be
especially important early in development,
potentially providing an embodied basis for
the
-
- cquisition of speech sounds, identifying
people, and novel tool use (Meltzoff, 1993) as
well as broader, more complex, aspects of so-
cial and empathic development (Nummenmaa,
Hirvonen, Parkkola, & Hietanen, 2008;
Preston & De Waal, 2002). In other words,
em- bodying the actions of others may foster
interpersonal connections by allowing the body
to implicitly feel and assign meaning to the ac-
tions of others, even before the onset of
language. Investigating the extent to which
individuals with ASD experience common forms of
contagion may shed light on developmental
processes that unfold differently in autistic
development.
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- 1.1 | Contagion and empathy
-
- Although definitions vary between fields and
theorists, most re- searchers would likely agree
that empathy is a multilevel construct,
involving both emotional processes (e.g.,
automatically forming a link between oneself and
another's inner state) and cognitive processes
(e.g., being able to take another person's
perspective). Certain ac- tions, such as
laughing, yawning, and itching, are
"contagious," mean- ing that they often result
in automatic mimicry and thus propagate through
a group (Hatfield, Cacioppo, & Rapson,
1993). For example, hearing a laugh produces
laughter in approximately half of listeners and
smiles in approximately 90% of listeners
(Provine, 1992). Seeing (Helt, Fein, &
Vargas, 2019; Provine & Hamernik, 1986) or
hearing a yawn (Helt et al., 2019; Massen,
Church, & Gallup, 2015) elicits yawning in
others between 30% and 60% of the time. The
behaviors that are most likely to be contagious
are those that signify the inner states of
others (Hatfield et al., 1993). Contagious
yawning, laughing, and itching are easily
observable signs of resonance between two
individuals, with one person taking on the
physiological and inner state of the other.
Contagion may reflect the emotional component of
empathy in that it results in the observer being
brought closer to the inner state of the target
without necessarily evoking the cogni- tive
component of empathy (e.g., newborns presumably
are unable to identify that another baby is the
source of the emotion when cry- ing
contagiously, and certainly cannot understand
why). This con- cept is referred to across the
literature as "emotional contagion" (Preston
& de Waal, 2002), "affective empathy"
(Davis, 1983), and "emotional empathy" (Blair,
2005).
-
- Several behavioral studies have suggested an
indirect associa- tion between contagious
yawning and cognitive components of em- pathy.
For example, susceptibility to contagious
yawning is positively related to performance on
self-face recognition and theory-of-mind tasks,
and negatively related to schizotypal traits
(Platek, Critton, Myers, & Gallup, 2003).
Norscia and Palagi (2011) reported conta- gious
yawning to be greatest in response to kin, then
friends, then acquaintances, and lastly
strangers, a pattern that is true for other
empathic behaviors (Preston & De Waal,
2002). However, Massen et al. (2015) point out
that this differential response in contagion may
have been due to individuals' tendency to pay
greater attention to kin than to strangers, and
reported that participants were no more likely
to yawn contagiously to a member of their
political "in" versus "out" group. In addition,
the majority of fMRI studies have reported an
association between a participants self-reported
desire to yawn while viewing others yawn in the
scanner (importantly, participants are unable to
yawn in an fMRI study and so these are measures
of the neural correlates of the urge to yawn as
opposed to true yawn conta- gion) and areas of
the brain associated with mirror neurons and
self- other processing (Arnott, Singhal, &
Goodale, 2009; Haker, Kawohl, Herwig, &
Ro_ssler, 2013; Nahab, Hattori, Saad, &
Hallett, 2009; Platek, Mohamed, & Gallup,
2005), although Schu_rmann et al. (2005)
reported no mirror neuron involvement.
-
- At the same time, correlational studies that
have probed direct links between participants'
susceptibility to contagious yawning and their
global empathy traits have, more often than not,
failed to find them (see Massen & Gallup,
2017, for a comprehensive review). Although
positive relationships between contagious yawn
suscepti- bility and direct measures of empathy
have been observed (Arnott et al., 2009),
several studies have reported non-significant
links be- tween susceptibility to yawn contagion
and scores on various empa- thy measures
(Bartholomew & Cirulli, 2014; Gottfried,
Lacinova_, & S_iru_c_ek, 2015; Haker &
Ro_ssler, 2009). We know of no studies that have
previously investigated a link between
contagious laughter and empathy. All of the
above suggest the need for more comprehen- sive
research into the link between contagion and
different forms of empathy. For the purposes of
the current study, the most important point may
be that individuals with, or at-risk for,
clinical disorders affecting empathy, such as
schizophrenia, callous and unemo- tional traits,
and psychopathic traits, show reduced
spontaneous susceptibility to both contagious
yawning (Haker & Ro_ssler, 2009; Rundle,
Vaughn, & Stanford, 2015) and contagious
laughter (Haker & Ro_ssler, 2009; O'Nions et
al., 2017).
-
- 1.2 | Contagion in ASD
-
- The question of whether contagion tends to
be "weak, intact, or heightened" in individuals
with ASD is a matter of some de- bate
(Minio-Paluello, Lombardo, Chakrabarti,
Wheelwright, & Baron-Cohen, 2009; Smith,
2009). Support for the "weak" theory includes
the fact that contagious yawning in individuals
with ASD is reduced across a variety of
contexts, including: ex- posure to examiner
yawns during a live interaction (Helt, Eigsti,
Snyder, & Fein, 2010), watching videos of
strangers yawning (Helt et al., 2019; Senju et
al., 2007), and listening to yawns (Giganti
& Esposito Ziello, 2009; Helt et al., 2019).
Susceptibility to contagious laughter is also
reduced in participants with ASD (Helt et al.,
2019). These findings are consistent with a
broader body of work suggest- ing that many
individuals with ASD show reduced congruent emo-
tional responses (Bacon, Fein, Morris,
Waterhouse, & Allen, 1998; Hadjikhani et
al., 2009; Scambler, Hepburn, Rutherford,
Wehner, & Rogers, 2007) and reduced
spontaneous mimicry (McIntosh, Reichmann-Decker,
Winkielman, & Wilbarger, 2006; Stel, van den
Heuvel, & Smeets, 2008).
-
- On the other hand, multiple studies have
reported intact, or even heightened, emotional
response to others among individu- als with ASD.
For example, Press, Richardson, and Bird (2010)
re- ported intact automatic mimicry of facial
actions among individuals with ASD. Similarly,
Hadjikhani et al. (2014) reported no differences
between participants with and without ASD in
brain activation of pain sharing regions when
participants were shown faces of oth- ers in
pain. Magne_e, De Gelder, Van Engeland, and
Kemner (2007) presented stimuli of emotional
expressions, as well as emotional ex- pressions
paired with voices to adults with ASD, and found
that, in comparison to controls with a history
of typical development, adults with ASD showed
intact in response to the faces paired with
voices, and heightened automatic facial mimicry
(as measured by electromy- ography) in response
to happy and fearful faces. Finally, pupillary
contagion (an important mechanism for transfer
of affective and arousal levels between
individuals; Prochazkova & Kret, 2017) in
in- dividuals with ASD is comparable to that of
controls when observing pictures of emotional
faces, despite less spontaneous attention to-
ward the eye region (Galazka et al., 2019). A
pupillometric study of infants at genetic risk
for ASD showed that high-risk infants exhib-
ited larger pupil dilations when observing
emotional face stimuli than controls (Wagner,
Luyster, Tager-Flusberg, & Nelson,
2016).
-
- A possible explanation for these disparate
findings comes from a growing body of research
suggesting that contagion among indi- viduals
with ASD is context dependent, and can be
increased under certain contexts relevant to
social motivation and attention. First, yawning
and laughter contagion appear to be comparable
to controls when participants with ASD are
explicitly cued to attend the eyes of the target
(Helt et al., 2019; Senju et al., 2009; Usui et
al., 2013). Critically, children with ASD also
yawn and laugh contagiously to the same extent
as typical peers when the yawning/laughing
target is their own parent (Helt et al., 2019),
suggesting a role for both so- cial attention
and social affiliation. Although not a direct
measure of contagion, highly verbal individuals
with ASD show intact neu- ral responses when
viewing the faces of others in pain (Hadjikhani
et al., 2014). Thus, it appears that individuals
with ASD demonstrate typical or near typical
levels contagion when either they are explic-
itly cued to attend to the relevant features (in
the studies above, the eyes) of the target, or
when they are spontaneously more attentive to a
target they perceive as more salient (i.e., a
parent or a person in pain).
- When looking at individual differences,
spontaneous contagion to unfamiliar others
appears to best predict autism symptom severity.
Autism symptom severity is inversely related to
the spontaneous (but not voluntary) mimicry of
the facial expressions of others (McIntosh et
al., 2006). Similarly, both yawning (Helt et
al., 2010, 2019) and laughing (Helt et al.,
2019) contagion are inversely correlated with
ASD severity, such that children with ASD who
are more likely to yawn/laugh contagiously have
fewer and/or less severe ASD symp- toms. Thus,
probing the conditions under which these
phenomena occur without explicit cueing or other
attentional manipulations may lead to a richer
understanding of core impairments in social
reciproc- ity in this population.
-
- 1.3 | Eye gaze and contagion
-
- One of the most consistent findings across
individuals with ASD is the tendency for reduced
attention to the eyes of others (Moriuchi, Klin,
& Jones, 2017). Behavioral studies have
shown that children with ASD often demonstrate
typical performance on simple tasks involving
understanding and imitating signals from the
hands, such as gestures and reaching, and that
adults with ASD show automatic mimicry of the
hand movements of others (Bird, Leighton, Press,
& Heyes, 2007; Smith & Bryson, 1998;
Southgate & Hamilton, 2008). In contrast,
studies examining performance on automatic
facial imitation tasks have produced mixed
results (Loveland et al., 1994; McIntosh et al.,
2006; but also Magne_e et al., 2007; Press et
al., 2010), suggesting the possibility that this
group may perform differently on tasks in which
the hands or body are being observed rather than
the face. The question of whether individuals
with ASD demonstrate less spontaneous contagion
to unfamiliar others under all conditions or
only under conditions in which the signal is
transmitted from the eyes has yet to be inves-
tigated behaviorally.
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- 1.4 | Contagious itching
-
- In addition to contagious yawning and
laughter, itching by con- tagion represents one
of only a few motor programs that can be
involuntarily induced by external (seeing or
hearing it) or in- ternal (thinking about it)
stimuli (Provine, 2012). Between 43% and 82% of
people experience contagious itch when exposed
to stimuli of others scratching, establishing
that contagious itch occurs as commonly as
contagious yawning and laughter (Papoiu, Wang,
Coghill, Chan, & Yosipovitch, 2011).
Contagious itch, like contagious yawning
(Anderson, Myowa-Yamakoshi, & Matsuzawa,
2004) and laughter (Davila-Ross, Allcock,
Thomas, & Bard, 2011), has even been
demonstrated in non-human pri- mates (Feneran et
al., 2013), pointing to its evolutionary history
among social species. Contagious itch involves
the perception of a target's behaviors, and
automatic mimicry of the target's be- haviors,
followed by a response that brings the
observer's inner state closer to that of the
target's. However, a direct relationship between
empathy and contagious itch has yet to be
directly inves- tigated. Indeed, contagious itch
has actually been shown to occur more frequently
in controls with high levels of neuroticism (the
tendency to experience negative emotion; Holle,
Warne, Seth, Critchley, & Ward, 2012).
-
- Evidence from both behavioral studies
(Papoiu et al., 2011; Ward, Burckhardt, &
Holle, 2013) and neuroimaging (Holle et al.,
2012) of adults with a typical developmental
history sug- gests that contagious itching is,
like laughter (Scott, Lavan, Chen, &
McGettigan, 2014) and yawning (Deputte, 1994),
associated with an inner state. Holle et al.
(2012) found that the thalamus, primary
somatosensory cortex, prefrontal (BA 44) and
premotor cortex, and anterior insula were all
activated while participants watched vid- eos of
other people scratching. They argued that a
feeling-based rather than an action-based system
has a more central role in con- tagious itch due
to the fact that the insula, a region associated
with the affective components of bodily
sensations, showed the more sustained activity
during contagious itch (importantly,
participants are unable to scratch in an fMRI
scanner, thus these are measures of the neural
correlates of a contagious itchy sensation
rather than true behavioral itching contagion).
Further supporting this idea, Papoiu et al.
(2011) and Ward et al. (2013) have demonstrated
that observers scratch body areas that differ in
location from those they observed (i.e.,
matching the feeling of being itchy rather than
the action of the target).
-
- Critically for the present study, unlike
contagious yawning (Provine, 1989) and
contagious laughter (Surakka & Hietanen,
1998), itching does not rely on visual attention
to the eyes or require any mimicry of the facial
region. The current study will explore the
relationship between contagious laughter,
yawning, and itch and individ- ual differences
in empathy and autism symptoms.
-
- 4 | DISCUSSION
-
- Children with ASD were less likely to yawn
and laugh contagiously compared with their TD
peers, but more likely to itch contagiously when
presented with videos of others performing these
actions. Contagious yawning and laughter were
positively correlated with emotional empathy in
controls, whereas contagious itching showed no
relationship to emotional empathy. In the ASD
group, contagious yawning and laughing did not
correlate significantly with autism symptoms,
whereas contagious itching did, such that
greater ASD symptom severity was associated with
more susceptibility to con- tagious itch.
Furthermore, across groups, contagious yawning
and contagious laughter were positively
correlated with one another, but neither was
significantly correlated with contagious
itching, suggest- ing the possibility that
contagious yawning and laughing may reflect or
rely upon a shared construct (perhaps the
tendency to look at the eyes of others) that is
distinct from contagious itching.
-
- These results are consistent with previous
research suggesting that individuals with ASD do
spontaneously observe and take on the in- ternal
states of unfamiliar others around them under
some conditions (Hadjikhani et al., 2014; Helt
et al., 2019; Magne_e et al., 2007; Press et
al., 2010). Whereas previous research has shown
that the tendency to do so under naturalistic
conditions is inversely related to ASD symp- tom
severity (in the cases of yawning, laughter, and
facial mimicry; Helt et al., 2010; Helt et al.,
2019; McIntosh et al., 2006), the current study
shows that under some circumstances (in the case
of itching) the ten- dency to engage in
spontaneous contagious behavior may be
positively associated with the ASD phenotype.
Below we discuss implications of our findings
for current autism theories, followed by several
accounts of why contagious itching may be
heightened in ASD.
-
- One category of psychological theories of
autism (theories of re- duced social resonance),
consistent with accounts of weakened conta-
gion, argues that reductions in social
motivation and affiliation toward others are at
the core of autism symptoms, and thus social
partners often fail to engage the attention and
interest of individuals with ASD (Chevallier,
Kohls, Troiani, Brodkin, & Schultz, 2012;
Fein, Pennington, Markowitz, Braverman, &
Waterhouse, 1986; Kanner, 1944; Uddin et al.,
2013). One specific type of reduced social
resonance theory is the "mirror neuron" theory
of autism (Ramachandran & Oberman, 2006;
Williams, Whiten, Suddendorf, & Perrett,
2001), which asserts that in- nate abnormalities
in the mirror neuron system of individuals with
ASD compromise their ability to spontaneously
experience a correspon- dence between themselves
and others, both in terms of observable physical
states and inner (mental) states.
- A second category of psychological theories
of autism (theories of overarousal and reduced
social attention), consistent with accounts of
heightened contagion, hypothesizes that many
stimuli are experienced by people on the
spectrum as painfully intense, leading to
selective attention and avoidance of social
input (Kinsbourne, 2011; Markram & Markram,
2010; Smith, 2009). According to these theories,
it is not that individuals with ASD do not find
others salient from birth, it is that they
instead find it overwhelming to interact with
others, and so they defensively turn their
attention inward as a compensatory mechanism to
regulate their arousal levels. Indeed, although
the relevant statisti- cal contrasts are not
reported, a longitudinal study of infants at
risk for ASD suggests that, as newborns, those
who later develop ASD (and who, for most of
their development, attend far less to social
stimuli) may in fact attend to social stimuli
more relative to those who do not develop ASD as
newborns (Jones & Klin, 2013).
- Each possibility suggests distinct
implications for the neural bases of reduced
contagion among individuals with ASD, and for
theories about the underpinnings of ASD
symptoms. The former im- plies a failure to
develop a typical neural system that is
requisite for social engagement. The latter
implies a social neural network that is intact,
but that the consequences of engaging with
others are too overwhelming and painful, and so
attention is withdrawn from the social world as
a compensatory mechanism.
-
- On the one hand, the results of the present
study do not shed direct light on whether an
individual with autism is only less likely to
"catch" the behaviors and emotions of others
because he/she is less likely to attend to the
actions of others (i.e., when contagion is re-
duced in ASD it is secondary to reduced social
attention), or whether individuals with autism
are less susceptible to contagious stimuli even
when they are attending (i.e., when contagion is
reduced in ASD it is driven by a deficit in
social resonance).
-
- On the other hand, the findings of increased
contagious itch among participants with ASD have
several theoretical implications. First, these
findings seem to be in direct opposition to the
("bro- ken") mirror neuron theory of autism, as
contagious itch activates the mirror neuron
system (Holle et al., 2012) and demonstrates
that individuals with ASD have the ability to
spontaneously experience a correspondence
between themselves and others, under some cir-
cumstances. In our view, the fact that
individuals with ASD show heightened contagious
itching suggests that they do not have in- nate
disruption to the mirror neuron system, as has
been previously proposed (Ramachandran &
Oberman, 2006; Rizzolatti & Fabbri- Destro,
2010; Williams et al., 2001), and is, rather,
more consistent with the notion that they have
had reduced developmental experi- ence
registering many types of co-action with others
and so their mirror networks are not as
efficient and automatic across as wide a range
of circumstances. Individuals with ASD show
markedly re- duced attention to the faces, and
particularly the eyes, of others beginning at 6
months of age (Osterling, Dawson, & Munson,
2002), which may lead to reduced efficiency in
the processing of facial sig- nals. In other
words, at least some neural mechanisms
underlying interpersonal engagement appear to be
intact, and in some cases even heightened, but
chronically underused, in children with
ASD.
-
- Second, we argue that any enhanced response
in the realm of perceiving and mimicking the
behavior of another is more difficult to
reconcile with theories of autism that posit
that all signals of unfamil- iar others are not
salient for individuals with ASD. The present
study contributes to a growing body of
literature making clear that some signals about
the inner states of others are quite salient and
automat- ically co-experienced by children with
ASD. In addition, the possible explanations for
our results (outlined below: avoidance of eye
region information, sensory abnormalities that
produce heightened response to seeing itch
stimuli, heightened emotional empathy in
general, or heightened personal distress only)
would each contribute to making the infant's
world more painful and increasing the infant's
desire to turn attention inward or to objects as
a self-regulation strategy, thus, we interpret
these findings as more consistent with
(overarousal) the- ories postulating
"heightened" contagion individuals with
ASD.
-
- Third, Vivanti and Rogers (2014) argue that
three distinct aspects of social learning are
critical for advancing knowledge in the area of
autism and the mirror neuron system: (a) the
mechanisms that allow for the implicit mapping
of and learning from others' behavior, (b) the
motivation to attend to, and model,
conspecifics, and (c) the flexible and selective
use of social learning. The present
results&emdash;in other words, the finding that
even one form of behavior of a stranger is im-
plicitly mapped and enacted by individuals with
ASD&emdash;are consistent with the notion that
the first of these mechanisms is intact among
in- dividuals with ASD and that the second of
these mechanisms should be the subject of
further study.
- In the results of the current study, some
forms of contagion (yawning and laughing)
appeared "weak" in participants with ASD
compared to TD controls, and another (itch)
appeared "heightened." We speculate that these
results are best viewed in terms of Vivanti and
Roger's (2014) second criteria, the motivation
to attend, and offer several possible
explanations for this pattern of results.
-
- 4.1 | Reduced visual attention to
eyes
-
- The first possible explanation for the
observation of heightened spontaneous contagion
in the case of itch, and reduced contagion in
the cases yawning and laughter in the present
sample, is that in- dividuals with ASD are more
likely to show spontaneous contagion to
unfamiliar others if the signal is not
transmitted via the eyes. It is pos- sible that
contagion that is elicited without the potential
confound of requiring direct eye gaze from the
participant with ASD reveals an underlying
tendency for heightened contagion in this
popula- tion. It may even be this initially
heightened arousal in response to the emotions
of others, which overwhelms the young child,
caus- ing them to avoid direct eye gaze as a
strategy for self-regulation (as when we turn
our own eyes away from something unpleasant;
Dalton et al., 2005). Indeed, individuals with
ASD experience both elevated arousal and
amygdala activity (Kaartinen et al., 2012;
Kyllia_inen & Hietanen, 2006; Kyllia_inen et
al., 2012; Stagg, Davis, & Heaton, 2013) in
response to direct eye gaze, over and above that
of their TD peers. These results align with
expert clinical accounts that individuals with
autism are often distressed by other
individuals' negative emotions as well as with
personal accounts from individu- als with ASD
who describe eye contact as stressful (e.g.,
Trevisan, Roberts, Lin, & Birmingham,
2017).
- 4.2 | Heightened personal distress
- Previous research has found that contagious
itch is related to indi- vidual traits of
neuroticism. Neuroticism is the tendency for
indi- viduals to feel unpleasant emotions, and
thus an important possible explanation for the
current pattern of results is that contagious
itch- ing may be related to one component of
empathy: personal distress. Davis (2018) argues
that the emotional component of empathy can be
divided into a combination of empathic concern,
the tendency to experience other-oriented
feelings of sympathy and compassion in response
to another's misfortune, and personal distress,
the ten- dency to experience self-oriented
feelings of discomfort and anxiety in response
to another's misfortune. Presumably the newborn
infant who cries in the nursery upon hearing
another infant's cry, despite perceiving and
mimicking the other's actions, thus bringing
their own inner state closer to that of the
target, is unable to distinguish self from
other, much less feel empathetic concern for the
other infant. Thus, it is conceivable that
feeling personal distress at the arousal of
others via emotional contagion is the earliest
component of either emotional or cognitive
empathy to develop.
-
- There is some evidence that individuals with
ASD self-re- port lower levels of empathic
concern and higher or equal levels of personal
distress compared to controls (Dziobek et al.,
2008; Lombardo, Barnes, Wheelwright, &
Baron-Cohen, 2007; Minio- Paluello et al.,
2009). In addition, at-risk infants later
diagnosed with ASD show higher levels of
personal distress than their counterparts who do
not go on to receive a diagnosis (Brian et al.,
2008; Bryson et al., 2007). Finally, children
with ASD show greater negative affect to
negative emotional displays and less positive
affect to positive emotional displays, both via
parent report, and as measured in the laboratory
(Capps, Kasari, Yirmiya, & Sigman,
1993).
-
- In typical development, children are
initially overwhelmed by the emotional
experience of observing a person in need of
help; as they mature, they learn to manage this
emotional reaction, and in turn in- creasingly
engage in pro-social helping behaviors (e.g.,
Batson et al., 1991). Thus, if personal distress
levels remain high for individuals with ASD,
this could have the consequence of stalling
further em- pathic development. According to
this account, one would expect individuals with
ASD to show increased autonomic reactivity when
witnessing others' distress, and when confronted
with social stimuli that might be perceived as
aversive and/or that are actively avoided (such
as itching).
-
- 4.3 | Emotional valence
- Another explanation for the increased rate
of contagious itch among participants with ASD
in this study may be that people on the au- tism
spectrum react differently to stimuli with
negative versus positive or neutral valence. It
is possible that the aspect of the contagious
itch stimuli that best explains the current
results is not the fact that the signal was not
transmitted from the eyes or face, or as a
result of any increased aspect of emotional
empathy, but rather that itching, un- like
laughter and yawning, is negatively valenced.
Contagious itching stimuli may induce feelings
of discomfort in the observer and ignite a
desire to "avoid" the source of this feeling and
behavior (indeed, many definitions of itch use
the word "unpleasant," and feelings of itch are
related to feelings of state anxiety; Ogden
& Zoukas, 2009). In contrast, contagious
laughter and yawning may be more likely to
engage "approach" and "affiliative" regions of
the brain. For exam- ple, it is presumably
adaptive for an organism to behaviorally syn-
chronize with its social group if they are
laughing or yawning so that the organism may
share in the group's increased decompression or
vigilance. In contrast, when viewing members of
one's social group scratching, it is presumably
adaptive to mobilize and "avoid" others and
start scratching lest the organism catch the
skin condition or insect bite that is causing
their conspecifics' itching.
-
- 4.4 | Tactile defensiveness
- A final possibility is that contagious itch
is related to other traits as- sociated with
ASD, such as sensory abnormalities, including
tactile defensiveness, or possibly increased
rates of atopic dermatitis, which itself entails
itching that drives this relationship. Tactile
de- fensiveness is characterized by behaviors,
such as rubbing, scratch- ing, negative
expressions, withdrawal, or avoidance in
response to tactile stimulation and is linked to
the rigid or inflexible behaviors, repetitive
verbalizations, and visual stereotypies, that
are often as- sociated with ASD (Baranek &
Berkson, 1994). Children with these types of
sensitivities might both be expected to show
more itch at baseline (as was found) and to be
more distressed by the sight of others itching.
In addition, contagious itch is higher among pa-
tients with atopic dermatitis (Papoiu et al.,
2011), and there have been some studies
suggesting that individuals with ASD have an
increased risk of presenting with atopic
dermatitis compared with typically developing
controls, although results have been incon-
sistent (Billeci et al., 2015). In the current
study, we found that chil- dren with ASD itched
more at baseline, which may reflect these
sensory/dermatological differences. However,
only contagious itching, and not baseline
itching, was positively correlated with au- tism
symptoms.
-
- 4.5 | Limitations and future
directions
- Interpretation of the current study is
limited in several ways. First, the
- present study did not employ eye tracking
and so does not shed light on the role of visual
attention to the eye region in behavioral conta-
gion. Second, we did not assess individual
components of empathy or tactile defensiveness
in our ASD participants. Future studies may
benefit from using a more fine-grained measure
of empathy to directly investigate whether
contagious itching is related to any particular
components of empathy, such as personal
distress. In addition, future research that
examines contagion of both positively and
negatively valenced stimuli from both the face
and body may tease apart the pos- sible reasons
why contagious itch is heightened in this
population.
-
- 4.6 | Conclusion
- Children with ASD appear to be capable of
spontaneously internalizing the bodily signals
of unfamiliar others and so as to come into
bodily resonance those around them, and, in the
case of contagious itch, dem- onstrate a
heightened tendency to do so, while at the same
time dis- playing a markedly reduced tendency to
do so in the case of contagious yawning and
laughter. People with ASD are often successfully
able to do something under some circumstances
(in this case, take on a bodily signal of
contagion) that they fail to do automatically
under other cir- cumstances. This type of
observation should steer research away from
theories that propose modular deficits in a
particular structure of the brain or type of
neuron, and toward accounts that invoke
differences in behavioral profiles in attention
and motivation, which are likely to determine
the boundary conditions within which key social
functions, like contagion, can be implemented.
In addition, the implications of an intact but
underused system imply that mass opportunities
for these
- early (often missed) experiences of shared
affect, especially interac- tions involving
attention to others' faces and eyes and
imitation, may benefit the child's ability build
a more efficient and automatic mirroring neural
network. Early intervention holds the
possibility of programming these early
experiences, in addition to increasing the
positive reward value of social interactions, by
using various reinforcement and altering
overwhelming contexts, and desensitizing
tactile, eye gaze, and other sensory
sensitivities. Improvement in spontaneous
emotional conta- gion may even serve as an
outcome measure of effective treatment.
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