Facial expressions during dyadic
interactions: The use of EMG to investigate
the influence of status and emotional state
Ursula Hess1, Pedro Herrera, & Patrick Bourgeois
University of Quebec at Montreal
Abstract
The present study had the goal to assess the influence of relative status
on facial mimicry and emotional contagion in a dyadic setting. For this,
the interaction partners' facial display was measured using facial EMG of
both speaker and listener at the Orbicularis Oculi, Zygomaticus Major,
Levator Labii Alesque Nasii, and Corrugator Supercilii sites while one
member of the dyad told a story about a personal event that elicited either
happiness or anger. Relative status was varied by giving the participants
false feedback about the results of a task relevant test. Evidence for
emotional contagion was found for anger and happiness situations.
Further, both speakers and listeners also showed more smiling behavior
when talking about happy events but no increase in frowning when talking
about anger events. As predicted, more Zygomaticus Major activity,
regardless of emotion content, was found for low status listener, a finding
congruent with a submissive social smile.
Introduction
The expression and interpretation of emotions plays an important part in
human interactions and the processes involved in the encoding and decoding
of emotional expressions have been the subject of numerous studies.
However, with the exception of studies focussing on dysfunctions in
emotion communication (e.g., interactions between partners in
dysfunctional marriages), most studies focus typically on individual subjects
1
Paper presented at the 39th meeting of the Society for
Psychophysiological Research, Granada, Spain, October 6-10. This research
was supported by a grant by the Conseil de Recherche en Sciences
Humaines. Correspondence should be addressed to Ursula Hess,
Department of Psychology, University of Quebec at Montreal, P.O. Box
8888, station A, Montreal, Qc, H3C 3P8, email: Hess.Ursula@UQAM.ca
in a non interactional context . However, most emotional experiences in
everyday life occur during interactions. Importantly, when studying
interactions, the social context (such as the gender composition of the dyad
or the relative status of the interaction partners) of these interactions presents
an important influence on emotional communication. The present study aims
to assess emotion communication processes in the context of a dyadic
interaction by explicitly varying the social context of the situation. The
specific process we are interested in is facial mimicry - the imitation of the
emotional displays of the interaction partner - and a related process
emotional contagion.
Facial mimicry can be reliably observed as a response to emotional
facial expressions shown as photos or on videotape (Hess et al. 1999).
Also, observers often report feeling a congruent emotional response in those
conditions. In the clinical literature, facial mimicry has been considered to
be of importance for the establishment and maintenance of rapport in
therapist-patient interactions. Thus, it is important to assess whether this
phenomenon can be observed in an everyday type interaction among
strangers.
Yet, as mentioned above, interactions do not occur in a social vacuum.
Social context variables such as the gender composition of the dyad and the
relative status of the interaction partners have been shown to influence
interactions. Specifically, low status has been related to increased smiling
(submissive smile; Henley, 1977). Also, it has been postulated that low
status individuals should be more attentive to the emotional displays of their
interaction partners and more easily influenced by their moods. Thus we
might expect higher levels of contagion and mimicry by low status
individuals. Further, Vrana and Rollock (1996) report evidence for more
intense positive and negative emotion in the (imagined) presence of
authority figures.
Overview
The goal of the present study was to assess the emotional facial
expressions and self-reported feeling states of interaction partners in a
dyadic setting in which the relative status of the interaction partners was
varied.
For this the facial display of the interaction partners was measured
using facial EMG at the Orbicularis Oculi, Zygomaticus Major, Levator
Labii Alesque Nasii, and Corrugator Supercilii sites while one member of
the dyad talks to the other about an event of their life that elicited either
happiness or anger. This task was chosen to elicit specific emotions in the
speaker by means of the social sharing of emotions (Rimé, 1991).
Relative status was varied by giving the participants false feedback
regarding the results of a task relevant test. Specifically, participants were
told that although both had scored above average on an emotional
intelligence test one of them had scored somewhat higher. The
experimenter then explained that based on this score the person with the
higher (lower) score would start by telling their story. Although this
manipulation is rather subtle previous research in our laboratory (Cantin &
Hess, 1997) has demonstrated its validity.
Hypotheses
General hypotheses


Speakers’ O. Oculi and Zygomaticus M. activity are higher when they
report a happy than when they report an angry event whereas Corrugator
S.activity is higher when they report an angry event.
Speakers report emotional states congruent with the emotion theme of
their report
Mimicry effect

Listeners’ facial EMG activity parallels the speakers’ facial activity
Contagion effect
 Listeners’ self -reported emotional state parallels the speakers’
Status effects



lower status participants are more expressive
submissive smiling is reflected in higher activity at the Zygomaticus M.
site for lower status listeners (as Zygomaticus M. has been suggested to
reflect the presence of a “social smile” whereas additional activity of the
O. Oculi muscle would suggest an “enjoyment smile”)
submissive smiling to be more pronounced when the speaker shows an
anger display as anger displays are associated with dominance (Kundson,
1996)
Method
Participants
48 female dyads with a mean age of 24.01 (6.27).
Procedure
First, participants were asked to fill out a series of questionnaires
including the bogus emotional intelligence questionnaire. They also filled
out a questionnaire asking them to briefly describe a situation when they
felt happy or angry and to answer questions regarding the emotion eliciting
situation. Once this part of the experiment was concluded the electrodes
were attached.
To habituate participants to the experimental situation and the presence
of the cameras they were then asked to play a story telling fantasy game.
Following this, the instructions incorporating the status manipulation were
given. Then each participant told one story and listened to one story. Thus
a total of 96 episodes were recorded. Role (speaker, listener), status (same,
lower, higher) and emotion content (happy, angry) for the first story were
counterbalanced across participants. For the second trial roles were
reversed and the story content switched. The participants were then
separated to watch the video recording of the interaction and to rate each
episode’s speaker (either themselves or their interaction partner), using an
action tendencies form, in 15 sec epochs up to a maximum of 24 epochs (6
minutes).
Dependent measures
Facial EMG: Activity of the O. Oculi, Zygomaticus M. Corrugator S.,
and Levator LAN was measured on the left side of the face using bipolar
placements of Med. Associates Inc. Ag/AgCl miniature surface electrodes
with Med Associates Inc. electrolyte gel (TD41). The skin was cleansed
with PDI disposable electrode prep pads (70% alcohol and pumice).
Electrode placements were chosen according to Fridlund and Cacioppo
(1986). A Contact Precision Instruments system with 60 Hz notch filter
was used to amplify the raw EMG signals, which were integrated with
200ms time constant. The smoothed EMG signal was sampled at 20 Hz
and stored to disk. Because of non-normality of the distribution EMG
measures were transformed using square root transformation.
Self-report measures: Prior to the status manipulation and following
each story, the participants’ emotional state was assessed using a
questionnaire describing common physical symptoms that one experience
(e.g., headache or tense muscles), as well as a number of items describing
emotional states (irritated/aggressive, sad/depressed, cheerful, positive
feeling).
Individual difference measures: Self-reports of Masculinity, Femininity
(PAQ), expressivity (BEQ - Berkeley expressivity questionnaire), social
dominance (IAS-R), empathy (Davis’ interpersonal reactivity index), FEQ
(Family expressiveness questionnaire) were obtained.
Decoding accuracy: The inter-rater agreement between the speaker’s
own and the listener’s ratings on the action tendency scale was assessed
using Cohen’s kappa.
Results
Manipulation check
•
•
•
Telling stories about happy events elicits self-reported feelings of happiness
as well as increases in Zygomaticus M. and O.Oculi activity.
Telling stories about anger eliciting events elicits self-reported feelings of
anger but no increases Corrugator S. activity.
Speakers’ Orbicularis O. and Zygomaticus M. activity correlated positively
with self-reported cheerfulness. Zygomaticus M. activity correlates
negatively with self-reported irritation.
Facial Mimicry
•
•
Participants showed more O. Oculi and Zygomaticus M. activity when
listening to happy (m = 5.44, sd = 1.39; m = 5.55, sd = 1.50) then when
listening to angry (m = 4.54, sd = 1.44; m = 4.78, sd = 1.64) stories, F(1,90)
= 9.76, p = .002 and F(1,90) = 5.97, p = .016, respectively. No differences
were found for Corrugator S.
Overall, the listeners’ Zygomaticus M. and O. Oculi activity is positively
correlated with the speakers’ self-reported cheerfulness and positive feeling,
and negatively with the speakers’ self-reported irritation and distress.
Figure 1. Participants' facial actovity
7
Speaker happy
Speaker anger
sit.
Listener happy
sit.
sit.
Listener anger
sit.
6
5
4
3
2
1
0
O.Ocul
i
Zygomaticus
M.
Muscle
site
Corrugator
S.
Table 1. Correlation between speakers' and listeners' facial activity
Speaker's emotional state
Listener's
Feeling
Irritated,
Sad,
facial
Cheerful
positive
aggressive
distressed
activity
Orbicularis O.
.25*
.29*
-.32*
-.26*
Zygomaticus M.
.16
.22*
-.26*
-.20*
Levator LAN
.13
.17
-.31**
-.26*
Corrugator S.
.01
.06
-.04
.04
Emotional Contagion
•
•
Listeners report significantly more cheerfulness and positive feeling when
listening to happy events and significantly more irritation when listening to
anger events.
The listeners’ self-reported cheerfulness and positive feeling are positively
correlated with the speakers’ self-reported cheerfulness and positive feeling
and negatively with the speakers’ irritation.
Figure 2. Participants' emotional state
Table 1. Correlation between speakers' and listeners' emotional state
Speaker's emotional state
Listener's
Feeling
Irritated,
Sad,
emotional
Cheerful
positive
aggressive distressed
state
Cheerful
.27**
.24*
-.25*
-.12
Feeling positive
.29**
.23*
-.23*
-.12
Irritated,
.01
-.01
.10
.15
aggressive
Sad, distressed
-.06
-.06
.15
.16
Status effects
•
•
•
•
No status effect on speakers’ facial displays emerged. Thus, lower status
speakers were not more expressive than higher status speakers.
Lower status listeners showed more Zygomaticus M. activity, regardless of
the emotion content of the story, F(2,90) = 2.99, p = .055.
The interaction partners’ agreement regarding their action tendency ratings
of the speaker’s videotaped facial expressions was higher when the speaker
had lower or the same status as the listener.
Inter-rater agreement correlates positively with the speaker’s social
dominance score (r = .22, p < .05) and negatively with the listener’s (r = -.24,
p < .05).
Figure 3. Listeners' Zygomaticus M. activity as a function of listener status
Figure 4. Interrater agreement as a function of speaker status
Discussion
The present study investigated emotion communication in a dyadic
interactive setting. The results show that the paradigm successfully elicits
emotional states of happiness and anger in the speaker. However, although
speakers smile more when talking about happy events, they do not frown
more when talking about anger events.
Emotional contagion effects were found for both conditions regardless
of status. For happy events only, the expected facial mimicry effects were
found with regard to O. Oculi activity. Zygomaticus M. activity varied as a
function of both emotion and status and the expected submissive smile
effect emerged: lower status participants smiled more and this regardless of
emotion condition. Status also influenced the level of inter-rater agreement
between the speaker and the listener regarding the speakers’ action
tendencies.
In sum, the present study demonstrates the influence of relative status
on emotional expressivity as well as speaker influences on the listeners’
facial displays and emotional state, in a realistic dyadic setting.