Predictors Of Stress Response Research Articles

Impact of acute stress on the canine gut microbiota

There is growing evidence that a relationship exists between mental and emotional wellbeing and the gut microbiota. Little is known regarding how the microbiota reacts to repeated acute stress events in dogs, and whether it is a predictor of stress response. In this study, we explored the impact on the gut microbiota and digestive health with two common events many pet dogs find stressful. Twenty healthy adult dogs, living within a colony, were exposed to either car travel or separation three times across eight-week intervals. Faecal samples were collected 24 h before, within 24 h, and 24–48 h after. Faecal quality and pH, and microbiota diversity and composition were analysed in context with wider published work on physiological stress measures. No significant changes were observed in faecal quality or pH with either stress event at any timepoint, indicating all pets remained in good digestive health. Microbiota analysis demonstrated no significant impact on alpha or beta diversity with either stressor. Microbial signatures previously linked to stress were not identified in these dogs and no changes were observed in the functional gut composition. Irrespective of whether the pet was considered “stressed” (i.e., exhibited an increase in serum cortisol), there was no effect on the microbiota and no taxa were predictive of stress response. Collectively, this work demonstrates, for this population, certain acute stress events have no meaningful impact on the canine gut microbiota, and it has no impact on the associated stress response.

Students' Perception of Teachers' Humor Predicts Their Mental Health.

The aim of the present study was to determine whether two types of teacher humor (Aggressive Humor and Affinity Humor) are predictors of students' mental health. A self-report scale was administered to 500 elementary and junior high school students in grades 4 to 9 (mean age 12.04, SD = 1.76) asking questions about perceived teacher humor, stress response, emotional well-being, and self-esteem. Aggressive humor was a significant positive predictor of stress response and a significant negative predictor of emotional well-being. Affinity humor was a significant positive predictor of emotional well-being and self-esteem. These results suggest that the teacher's humor is related to students' mental health. We conclude that teachers should refrain from using aggressive humor as much as possible in favor of affinity humor.

Social group dynamics predict stress variability among children in a New Zealand classroom

Previous research proposes stress as a mechanism for linking social environments and biological bodies. In particular, non-human primate studies investigate relationships between cortisol as a measure of stress response and social hierarchies. Because human social structures often include hierarchies of dominance and social status, humans may exhibit similar patterns. Studies of non-human primates, however, have not reached consistent conclusions with respect to relationships between social position and levels of cortisol. While human studies report associations between cortisol and various aspects of social environments, studies that consider social status as a predictor of stress response also report mixed results. Others have argued that perceptions of social status may have different implications for stress response depending upon social context.We propose here that characteristics of children’s social networks may be a better predictor of central tendencies and variability of stress response than their perceptions of social status.This is evaluated among 24 children from 9.4 to 11.3 years of age in one upper middle-class New Zealand primary school classroom, assessed through observation within the classroom, self-reports during semi-structured interviews and 221 serial saliva samples provided daily over 10 consecutive school days. A synthetic assessment of the children’s networks and peer-relationships was developed prior to saliva-cortisol analysis. We found that greater stability of peer-relationships within groups significantly predicts lower within-group variation in mid-morning cortisol over the two-week period, but not overall within-group differences in mean cortisol.

Responses of Plants to Multiple Stresses.

Structure, Function, and Resources: R.E. Dickson and J.G. Isebrands, Leaves as Regulators of Stress Response. C.B. Field, Ecological Scaling of Carbon Gain to Stress and Resource Availability. F.S. Chapin III, Effects of Multiple Environmental Stresses on Nutrient Availability and Use. E.-D. Schulze, Water and Nutrient Interactions with Plant Water Stress. D.R. Geiger and J.C. Servaites, Carbon Allocation and Response to Stress. H.A. Mooney and W.E. Winner, Partitioning Response of Plants to Stress. J.P. Crime and B.D. Campbell, Growth Rate, Habitat Productivity, and Plant Strategy as Predictors of Stress Response. N.R. Chiariello and S.L. Gulmon, Stress Effects on Plant Reproduction. E.J. Pell and M.S. Dann, Multiple Stress-Induced Foliar Senescence and Implications for Whole-Plant Longevity. P.J.H. Sharpe and E.J. Rykiel, Jr. , Modeling Integrated Response of Plants to Multiple Stresses. Biotic Interactions: P.G. Ayres, Growth Responses Induced by Pathogens and Other Stresses. C.G. Jones and J.S. Coleman, Plant Stress and Insect Herbivory. Plant Growth Forms: F.A. Bazzaz and S.R. Morse, Annual Plants: Potential Responses to Multiple Stresses. S.J. McNaughton, Dryland Herbaceous Perennials. J.E. Keeley, Interactive Role of Stresses on Structure and Function in Aquatic Plants. P.W. Rundel, Shrub Life-Forms. R.H. Waring, Responses of Evergreen Trees to Multiple Stresses. T.T. Kozlowski, Effects of Environmental Stresses on Deciduous Trees. Index.