scholarly journals Puffing up as a defensive reaction of the yellow-bellied toad Bombina variegata

2021 ◽  
pp. 41-41
Author(s):  
Laciak Malgorzata
Keyword(s):  
Defensive Reaction ◽  
Bombina Variegata

Effect of Heart Rate Variability on Defensive Reaction and Eating Disorder Symptomatology in Chocolate Cravers

2009 ◽  
Vol 23 (3) ◽  
pp. 95-103 ◽  
Author(s):  
Sonia Rodríguez-Ruiz ◽  
Elisabeth Ruiz-Padial ◽  
Nieves Vera ◽  
Carmen Fernández ◽  
Lourdes Anllo-Vento ◽  
...  
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Eating Disorder ◽  
Eating Behavior ◽  
Rest Period ◽  
Food Craving ◽  
Defensive Reaction ◽  
Relevant Role ◽  
Eating Disorder Symptomatology ◽  
Uncontrolled Eating

The study examines the effect of heart rate variability (HRV) on the cardiac defence response (CDR) and eating disorder symptomatology in chocolate cravers. Female chocolate cravers (n = 36) and noncravers (n = 36) underwent a psychophysiological test to assess their HRV during a 5-min rest period, followed by three trials to explore the CDR, elicited by an intense white noise, during the viewing of chocolate, neutral, and unpleasant pictures. After the test, participants completed a questionnaire to measure eating disorder symptomatology. The HRV was inversely related to the magnitude of the CDR and to eating disorder symptomatology in chocolate cravers. In addition, the HRV was inversely related to the magnitude of the CDR when viewing unpleasant pictures but not to neutral or chocolate ones, across all participants. These findings support the idea that poor autonomic regulation, indexed by low HRV, plays a relevant role in food craving and uncontrolled eating behavior.

Empathy Does Not Amplify Vicarious Threat Learning

2019 ◽  
Author(s):  
Alexander Lane Williams ◽  
Christopher C Conway
Keyword(s):  
Individual Differences ◽  
Skin Conductance ◽  
Defensive Response ◽  
Conditioned Stimuli ◽  
Defensive Reaction ◽  
Direct Exposure ◽  
Conditioned Responses ◽  
Clinically Significant ◽  
Stimulus Materials ◽  
Dispositional Empathy

Clinically significant fears and phobias can be acquired vicariously. Witnessing a demonstrator’s defensive reaction to potentially dangerous objects and situations can instill conditioned threat responses in the observer. The present study concentrates on individual differences in this social learning process. Specifically, we hypothesized that dispositional empathy modulates vicarious threat conditioning. We examined university students’ (N = 150) conditioned threat responding after they observed strangers undergo Pavlovian threat conditioning. There was evidence of a substantial conditioned defensive response (Cohen’s d = 0.66), as indexed by elevated skin conductance reactions during participants’ direct exposure to the vicariously conditioned stimuli. Contrary to expectations, indices of dispositional empathy were weakly related to the size of conditioned responses (median r = .04). Our results confirm that vicarious threat learning can be evaluated experimentally, but they do not support the hypothesis that empathy amplifies this process. The preregistration, stimulus materials, data, and analysis code for this study are available at https://osf.io/h6hm2.

Physical Warmth Attenuates Ethnocentric Bias under Mortality Salience: An Embodied Terror Management Perspective

2020 ◽  
Author(s):  
Armand Chatard ◽  
Margaux Renoux ◽  
Jean Monéger ◽  
Leila Selimbegovic
Keyword(s):  
Mortality Salience ◽  
Terror Management ◽  
Negative Consequences ◽  
Defensive Reaction ◽  
Worldview Defense ◽  
Management Perspective ◽  
Physical Warmth ◽  
Alternative Means ◽  
First Time

Research indicates that individuals often deal with mortality salience by affirming beliefs in national or cultural superiority (worldview defense). Because worldview defense may be associated with negative consequences (discrimination), it is important to identify alternative means to deal with death-related thoughts. In line with an embodied terror management perspective, we evaluate for the first time the role of physical warmth in reducing defensive reaction to mortality salience. We predicted that, like social affiliation (social warmth), physical warmth could reduce worldview defense when mortality is salient. In this exploratory (preregistered) study, 202 French participants were primed with death-related thoughts, or an aversive control topic, in a heated room or a non-heated room. The main outcome was worldview defense (ethnocentric bias). We found no main effect of mortality salience on worldview defense. However, physical warmth reduced worldview defense when mortality was salient. Implications for an embodied terror management perspective are discussed.

scholarly journals Effects of Desiccation on Metamorphic Climax in Bombina variegata: Changes in Levels and Patterns of Oxidative Stress Parameters

Animals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 953
Author(s):  
Tamara G. Petrović ◽  
Ana Kijanović ◽  
Nataša Kolarov Kolarov Tomašević ◽  
Jelena P. Gavrić ◽  
Svetlana G. Despotović ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Oxidative Damage ◽  
Antioxidant System ◽  
Water Availability ◽  
System Control ◽  
Glutathione S Transferase ◽  
Oxidative Stress Parameters ◽  
Metamorphic Climax ◽  
Bombina Variegata ◽  
Stress Parameters

In this paper, we examined how the oxidative status (antioxidant system and oxidative damage) of Bombina variegata larvae changed during the metamorphic climax (Gosner stages: 42—beginning, 44—middle and 46—end) and compared the patterns and levels of oxidative stress parameters between individuals developing under constant water availability (control) and those developing under decreasing water availability (desiccation group). Our results revealed that larvae developing under decreasing water availability exhibited increased oxidative damage in the middle and end stages. This was followed by lower levels of glutathione in stages 44 and 46, as well as lower values of catalase, glutathione peroxidase, glutathione S-transferase and sulfhydryl groups in stage 46 (all in relation to control animals). Comparison between stages 42, 44 and 46 within treatments showed that individuals in the last stage demonstrated the highest intensities of lipid oxidative damage in both the control and desiccation groups. As for the parameters of the antioxidant system, control individuals displayed greater variety in response to changes induced by metamorphic climax than individuals exposed to desiccation treatment. The overall decrease in water availability during development led to increased oxidative stress and modifications in the pattern of AOS response to changes induced by metamorphic climax in larvae of B. variegata.

scholarly journals Evolution of a predator-induced, nonlinear reaction norm

2017 ◽  
Vol 284 (1861) ◽  
pp. 20170859 ◽  
Author(s):  
Mauricio J. Carter ◽  
Martin I. Lind ◽  
Stuart R. Dennis ◽  
William Hentley ◽  
Andrew P. Beckerman
Keyword(s):  
Evolutionary Dynamics ◽  
Daphnia Pulex ◽  
Reaction Norm ◽  
Maximum Response ◽  
Selective Predation ◽  
Evolutionary Trajectory ◽  
Defensive Reaction ◽  
Selection Gradients ◽  
Hunting Strategies ◽  
Evolutionary Response

Inducible, anti-predator traits are a classic example of phenotypic plasticity. Their evolutionary dynamics depend on their genetic basis, the historical pattern of predation risk that populations have experienced and current selection gradients. When populations experience predators with contrasting hunting strategies and size preferences, theory suggests contrasting micro-evolutionary responses to selection. Daphnia pulex is an ideal species to explore the micro-evolutionary response of anti-predator traits because they face heterogeneous predation regimes, sometimes experiencing only invertebrate midge predators and other times experiencing vertebrate fish and invertebrate midge predators. We explored plausible patterns of adaptive evolution of a predator-induced morphological reaction norm. We combined estimates of selection gradients that characterize the various habitats that D. pulex experiences with detail on the quantitative genetic architecture of inducible morphological defences. Our data reveal a fine scale description of daphnid defensive reaction norms, and a strong covariance between the sensitivity to cues and the maximum response to cues. By analysing the response of the reaction norm to plausible, predator-specific selection gradients, we show how in the context of this covariance, micro-evolution may be more uniform than predicted from size-selective predation theory. Our results show how covariance between the sensitivity to cues and the maximum response to cues for morphological defence can shape the evolutionary trajectory of predator-induced defences in D. pulex .

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