The overt and reflexive matching of behaviors among
conspecifics has been observed in a growing number of
social vertebrates, including avian species. In general,
behavioral contagion&emdash;such as the spread of
yawning&emdash;may serve important functions in group
synchronization and vigilance behavior. Here, the authors
performed an exploratory study to investigate yawn
contagion among 10 captive juvenile ravens (Corvus
corax), across two groups. Using observational methods,
we also examined the contagiousness of three other
distinct behaviors: stretching, scratching, and shaking.
A total of 44 20 min observations were made across both
groups, including 28 in the morning and 16 in the
afternoon. The time and occurrence of all the behaviors
from each bird were coded, and the temporal pattern of
each behavior across both groups was then analyzed to
assess the degree of social contagion. Overall, they
found no evidence for contagious yawning, stretching,
scratching, or shaking. However, yawns were relatively
infrequent per observation (0.052 ± 0.076
yawns/bird) and thus experimental methods should be used
to support this finding.
Pas
d'évidence de la réplication du
bâillement chez le corbeau
La correspondance manifeste et réflexive des
comportements entre congénères a
été observée chez un nombre
croissant de vertébrés sociaux, y compris
chez les espèces aviaires. En
général, la contagion comportementale -
telle que la propagation des bâillements - peut
remplir des fonctions importantes dans la synchronisation
des groupes et le comportement de vigilance. Ici, les
auteurs réalisé une étude
exploratoire pour étudier la contagion des
bâillements chez 10 corbeaux juvéniles en
captivité (Corvus corax), dans deux groupes. En
utilisant des méthodes d'observation, ils ont
également examiné la contagiosité de
trois autres comportements distincts :
l'étirement, le grattage et le tremblement. Un
total de 44 observations de 20 minutes a
été réalisé dans les deux
groupes, dont 28 le matin et 16 l'après-midi.
L'heure et l'occurrence de tous les comportements de
chaque oiseau ont été codées, et le
schéma temporel de chaque comportement dans les
deux groupes a ensuite été analysé
pour évaluer le degré de contagion sociale.
Globalement, ils n'ont trouvé aucune preuve de
contagion des bâillements, des étirements,
des grattages ou des secousses. Cependant, les
bâillements étaient relativement peu
fréquents par observation (0,052 ± 0,076
bâillements/oiseau) et des méthodes
expérimentales devraient donc être
utilisées pour étayer cette
constatation.
(Chapter VII. Transitory
Symptom-Constructions During the Analysis):
Expression
displacements. I noticed with one patient that
he yawned with striking frequency. I then remarked that
the yawning accompanied just those analytic conversations
whose content, would more suitably have evoked interest
than boredom. Another patient who came to treatment soon
after this `brought me what I believe to be the solution
of this peculiar phenomenon. She also yawned often and at
inappropriate times, but in her case the yawning was
sometimes accompanied with a flow of tears. That gave me
the idea that these patients' yawning might be a
distorted sigh, and in both cases the analysis confirmed
my surmise. The censorship effected in both cases the
repression of certain disagreeable emotional states that
were aroused through the analysis (pain, grief), but it
was unable to bring about a complete suppression, only a
displacement of the movements of expression, one that was
enough, however, to conceal from consciousness the real
character of the emotional state. On turning my
attention, after these observations, to the movements of
expression with other patients as well, I found that
there are other forms of "expression displacements."
[…] We see that the displacement from one
emotional expression to another takes place along the
line of physiological vicinity (yawning-sighing;
talking-coughing).
