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Integrating Tinbergen's inquiries: Mimicry and play in humans and other social mammals
Full text linkVisual signals convey emotions and intentions between
individuals. Darwin underlined that human facial expressions
represent a shared heritage between our species and
many other social mammals. Social play is a fertile field to
examine the role and the potential communicative function of
facial expressions. The relaxed open-mouth (or play face) is a
context-specific playful expression, which is widespread in
human and non-human mammals. Here, we focus on playful
communication by applying Tinbergen’s four areas of inquiry:
proximate causation, ontogeny, function, and evolution. First
of all we explore mimicry by focusing on its neural substrates
and factors of modulation within playful and non-playful context
(proximate causation). Play face is one of the earliest
facial expressions to appear and be mimicked in neonates.
The motor resonance between infants and their caregivers is
essential later in life when individuals begin to engage in
increasingly complex social interactions, including play
(ontogeny). The success of a playful session can be evaluated
by its duration in time. Mirroring facial expressions prolongs
the session by favoring individuals to fine-tune their own motor
sequences accordingly (function). Finally, through a comparative
approach we also demonstrate that the elements constituting
play communication and mimicry are sensitive to the
quality of interindividual relationships of a species, thus
reflecting the nature of its social network and style (evolution).
In conclusion, our goal is to integrate Tinbergen’s four areas of
ethological inquiry to provide a broader framework regarding
the importance of communication and mimicry in the play
domain of humans and other social mammals
Mimic Me While Playing! Social Tolerance and Rapid Facial Mimicry in Macaques (Macaca tonkeana and Macaca fuscata)
No full textSocial play and tolerance are positively correlated and playful signals are more freely expressed in egalitarian than in despotic species. Macaque species are organized along a continuum from intolerant to tolerant social systems and, for this reason, they are good models to test some hypotheses about the possible linkage between communication and tolerance. We compared facial playful communication in 2 macaque species at opposite ends of the continuum: despotic Japanese macaques, Macaca fuscata, and tolerant Tonkean macaques, Macaca tonkeana. We predicted that tolerance has favored larger facial display repertoires and playful cooperative tendency. Moreover, we evaluated if tolerance could also reflect in the selection for emotional sharing expressed through rapid facial mimicry (RFM). RFM is an automatic, unconscious, and fast (1 s) motor mirror response which favors emotional communication between subjects. Although M. fuscata and M. tonkeana performed play faces (PF) at comparable levels, only Tonkean macaques showed the phenomenon of RFM. The playful sessions characterized by RFM lasted longer than those characterized by the presence of playful signals perceived by a playmate but not followed by mimicry. Interestingly, the duration of playful sessions in Tonkean macaques overcame that of the sessions in Japanese macaques. It is likely that RFM improves communicative exchanges between the playmates and, at the same time, promotes behavioral coordination and cooperation in the sequence of actions. The tolerant nature of Tonkean macaques, also expressed in play, can foster RFM which, at the same time, positively enhances the propensity to cooperate in a sort of positive feedback
Relaxed open mouth reciprocity favours playful contacts in south american sea lions (Otaria flavescens)
No full textFine-tuning communication is well documented in mammalian social play which relies on a large variety of
specific and non-specific signals. Facial expressions are one of the most frequent patterns in play communication.
The reciprocity of facial signals expressed by the players provides information on their reciprocal attentional
state and on the correct perception/decoding of the signal itself. Here, for the first time, we explored the Relaxed
Open Mouth (ROM), a widespread playful facial expression among mammals, in the South American sea lion
(Otaria flavescens). In this species, like many others, ROM appears to be used as a playful signal as distinct from
merely being a biting action. ROM was often reciprocated by players. Even though ROM did not vary in
frequency of emission as a function of the number of players involved, it was reciprocated more often during
dyadic encounters, in which the players had the highest probability to engage in a face-to-face interaction.
Finally, we found that it was the reciprocation of ROMs, more than their frequency performance, that was
effective in prolonging playful bouts. In conclusion, ROM is widespread in many social mammals and O.
flavescens is not an exception. At least in those species for which quantitative data are available, ROM seems to
be characterized by similar design features clearly indicating that the signal underwent to similar selective
pressures
The role of peroxisomes during adult neurogenesis in a mouse model of Alzheimer's disease. In: Proceedings of the 63rd Congress of the Italian Embryological Group (GEI)
No full textAre horses capable of mirror self-recognition? A pilot study
Full text linkMirror Self-Recognition (MSR) unveils complex cognitive, social and emotional skills and it
has been found only in humans and few other species, such as great apes, dolphins, elephants
and magpies. In this pilot study, we tested if horses show the capacity of MSR. Four
subjects living socially under naturalistic conditions were selected for the experiment. We
adopted the classical mark test, which consists in placing a coloured mark on an out-of-view
body part, visible only through mirror inspection. If the animal considers the image as its
own, it will use its reflection to detect the mark and will try to explore it. We enhanced the
classical paradigm by introducing a double-check control. Only in the presence of the
reflecting surface, animals performed tactile and olfactory exploration of the mirror and
looked behind it. These behaviors suggest that subjects were trying to associate multiple
sensory cues (visual, tactile and olfactory) to the image in the mirror. The lack of correspondence
between the collected stimuli in front of the mirror and the response to the colored
mark lead us to affirm that horses are able to perceive that the reflected image is incongruent
when compared with the memorized information of a real horse. However, without replication
of data, the self-directed behavior towards the colored marks showed by our horses
cannot be sufficient per se to affirm that horses are capable of self-recognition
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Impaired spatio-temporal coordination of subventricular neurogenesis is restored by physical exercise
No full textA major aim of neural stem cells field is to harness endogenous neurogenesis to replace neurons damaged as a consequence of brain damage and neurodegeneration. Olfactory interneurons arise throughout life from neural stem cells residing in the subventricular zone (SVZ) of the lateral ventricle. Post mitotic neuroblast then migrate along the rostral migratory stream (RMS) to the olfactory bulb where undergone to fully maturation and functional integration in the olfactory circuitry. To ensure a continuous source of newly-generated adult interneurons, stem and progenitor cell proliferation, neuroblast migration, and terminal differentiation must be tightly coordinated. In this study we analyzed the effect of physical exercise in orchestrating the different steps of subventricular neurogenesis in a mouse lacking the antiproliferative gene Btg1 which displays an impaired subventricular neurogenesis. As previously demonstrated Btg1 loss-of-function mice exhibit a strong reduction of proliferation associated with a premature exit from the cell cycle and an anticipated migration toward the olfactory bulb where the neuroblast fail to fully differentiate and consequently to be specifically recruited in olfactory-dependent memory circuitry.
In the study we demonstrate that running fully reverses the profound reduction of proliferation within the SVZ of the lateral ventricle in the Btg1-deficient mice, mainly through a recruitment and expansion of the quiescent neural stem cells (NSCs) . Moreover, cell cycle analysis reveals that 12 days of running induces a shortening of the S-phase and consequently of the whole cell cycle length in both neural stem (GFAP+, type C) and progenitor (DCX+, type A) cells of Btg1 knockout mice, allowing the restoring of a proper coordination between the cell cycle exit and the initial phase of post-mitotic neuroblasts migration. These events result in a increased rate of terminal maturation and integration in the olfactory- dependent memory circuits. Finally, as previously stated by others, we does not detect any beneficial effect of running in the subventricular zone wild type mice . All together these in vivo data suggest that a) the quiescent state of neural stem cells lacking the cell cycle inhibitory control can be reactivated by running; b) the cell cycle kinetics in the adult SVZ plays a pivotal role not only for proliferation but also for the tight coordination of cell cycle exit, migration and terminal differentiation.
In vitro analysis demonstrates that running induces a great expansion of primary neurospheres isolated by Btg1 ko subvrenticular zone, supporting the in vivo observation about the increase of neural stem pool in this neurogenic niche. However the running-dependent hyperproliferation of the neural stem cells leads to a rapid depletion of the stem cell pool and /or to its ability to further expand in vitro. This fact suggest that the effect of running on the Btg1 knock out neural stem cell proliferation is not cell-autonomous but strictly dependent on niche environment. We can hypothesized that the presence of still unknown factors triggered by physical activity in the subventricular niche promotes and maintains in vivo the hyperproliferative state of neural stem cells in the Btg1 knockout mice
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