Workplace Bullying and Mental Health: A Meta-Analysis on Cross-Sectional and Longitudinal Data

Background

A growing body of research has confirmed that workplace bullying is a source of distress and poor mental health. Here we summarize the cross-sectional and longitudinal literature on these associations.

Methods

Systematic review and meta-analyses on the relation between workplace bullying and mental health.

Results

The cross-sectional data (65 effect sizes, N = 115.783) showed positive associations between workplace bullying and symptoms of depression (r = .28, 95% CI = .23–.34), anxiety (r = .34, 95% CI = .29–.40) and stress-related psychological complaints (r = .37, 95% CI = .30–.44). Pooling the literature that investigated longitudinal relationships (26 effect sizes, N = 54.450) showed that workplace bullying was related to mental health complaints over time (r = 0.21, 95% CI = 0.13–0.21). Interestingly, baseline mental health problems were associated with subsequent exposure to workplace bullying (r = 0.18, 95% CI = 0.10–0.27; 11 effect sizes, N = 27.028).

Limitations

All data were self-reported, raising the possibility of reporting- and response set bias.

Conclusions

Workplace bullying is consistently, and in a bi-directional manner, associated with reduced mental health. This may call for intervention strategies against bullying at work.     

Do sex hormones at birth predict later-life economic preferences? Evidence from a pregnancy birth cohort study

Economic preferences may be shaped by exposure to sex hormones around birth. Prior studies of economic preferences and numerous other phenotypic characteristics use digit ratios (2D : 4D), a purported proxy for prenatal testosterone exposure, whose validity has recently been questioned. We use direct measures of neonatal sex hormones (testosterone and oestrogen), measured from umbilical cord blood (n = 200) to investigate their association with later-life economic preferences (risk preferences, competitiveness, time preferences and social preferences) in an Australian cohort (Raine Study Gen2). We find no significant associations between testosterone at birth and preferences, except for competitiveness, where the effect runs opposite to the expected direction. Point estimates are between 0.05–0.09 percentage points (pp) and 0.003–0.14 s.d. We similarly find no significant associations between 2D : 4D and preferences (n = 533, point estimates 0.003–0.02 pp and 0.001–0.06 s.d.). Our sample size allows detecting effects larger than 0.11 pp or 0.22 s.d. for testosterone at birth, and 0.07 pp or 0.14 s.d. for 2D : 4D (α = 0.05 and power = 0.90). Equivalence tests show that most effects are unlikely to be larger than these bounds. Our results suggest a reinterpretation of prior findings relating 2D : 4D to economic preferences, and highlight the importance of future large-sample studies that permit detection of small effects.     

Parasite prevalence and the worldwide distribution of cognitive ability

In this study, we hypothesize that the worldwide distribution of cognitive ability is determined in part by variation in the intensity of infectious diseases. From an energetics standpoint, a developing human will have difficulty building a brain and fighting off infectious diseases at the same time, as both are very metabolically costly tasks. Using three measures of average national intelligence quotient (IQ), we found that the zero-order correlation between average IQ and parasite stress ranges from r = −0.76 to r = −0.82 (p < 0.0001). These correlations are robust worldwide, as well as within five of six world regions. Infectious disease remains the most powerful predictor of average national IQ when temperature, distance from Africa, gross domestic product per capita and several measures of education are controlled for. These findings suggest that the Flynn effect may be caused in part by the decrease in the intensity of infectious diseases as nations develop.     

Association of salivary steroid hormones and their ratios with time-domain heart rate variability indices in healthy individuals

BackgroundStress system consists of the hypothalamicpituitary-adrenal (HPA) axis and the locus caeruleus/norepinephrine-autonomic nervous system (ANS). Traditionally, HPA axis activity is evaluated by measuring its end-product cortisol, while the activity of ANS is assessed using heart rate variability (HRV) indices. Alterations in cortisol levels and HRV measures during laboratory-based stress tasks were extensively studied in previous research. However, scarce data exist on the associations of HRV measures with the levels of other adrenal steroid hormones under baseline conditions. Thus, we aimed to evaluate the activity of the HPA axis by measuring salivary cortisol, cortisone, dehydroepiandrosterone (DHEA) levels, and their ratios and to examine its association with HRV measures in a sample of healthy young and middle-aged adults.MethodsFor each participant (n=40), three data collection sessions taking place at the same time of the day were scheduled within five working days. Participants completed a self-reported questionnaire on sociodemographic and lifestyle characteristics, filled out t h e Perceived Stress Scale and State-Trait Anxiety Inventory. Also, saliva samples were collected, and physiological measures, including resting HR and HRV, were recorded during three data collection sessions.ResultsStatistically significant associations between diminished parasympathetic vagal tone evaluated by time domain HRV measures and higher salivary cortisol, lower DHEA levels, as well as decreased DHEA to cortisol ratio, were found. Also, physiological stress indicators (i.e., HRV) showed greater intraindividual stability compared with biochemical biomarkers (i.e., salivary steroid hormones) within five days.ConclusionsOur findings suggest that both cortisol and DHEA mediate the link between two stress-sensitive homeostatic systems.     

The ontogeny of human prosociality: behavioral experiments with children aged 3 to 8

Humans regularly engage in prosocial behavior that differs strikingly from that of even our closest living relatives, the chimpanzees (Pan troglodytes). In laboratory settings, chimpanzees are indifferent when given the opportunity to deliver valued rewards to conspecifics, while even very young human children have repeatedly been shown to behave prosocially. Although this broadly suggests that prosocial behavior in chimpanzees differs from that of young human children, the methods used in prior work with children have also differed from the methods used in studies of chimpanzees in potentially crucial ways. Here we test 92 pairs of 3–8-year-old children from urban American (Los Angeles, CA, USA) schools in a face-to-face task that closely parallels tasks used previously with chimpanzees. We found that children were more prosocial than chimpanzees have previously been in similar tasks, and our results suggest that this was driven more by a desire to provide benefits to others than a preference for egalitarian outcomes. We did not find consistent evidence that older children were more prosocial than younger children, implying that younger children behaved more prosocially in the current study than in previous studies in which participants were fully anonymous. These findings strongly suggest that humans are more prosocial than chimpanzees from an early age and that anonymity influences children's prosocial behavior, particularly at the youngest ages.     

Genetic dissimilarity,genetic diversity,and mate preferences in humans

It is clear that genes at the major histocompatibility complex (MHC) are involved in mate preferences in a range of species, including humans. However, many questions remain regarding the MHC's exact influence on mate preference in humans. Some research suggests that genetic dissimilarity and individual genetic diversity (heterozygosity) at the MHC influence mate preferences, but the evidence is often inconsistent across studies. In addition, it is not known whether apparent preferences for MHC dissimilarity are specific to the MHC or reflect a more general preference for genome-wide dissimilarity, and whether MHC-related preferences are dependent on the context of mate choice (e.g., when choosing a short-term and long-term partner). Here, we investigated whether preferences for genetic dissimilarity are specific to the MHC and also whether preferences for genetic dissimilarity and diversity are context dependent. Genetic dissimilarity (number of alleles shared) influenced male, but not female, partner preferences, with males showing a preference for the faces of MHC-dissimilar females in both mating contexts. Genetic diversity [heterozygosity (H) and standardized mean (d²)] influenced both male and female preferences, regardless of mating context. Females preferred males with greater diversity at MHC loci (H) and males preferred females with greater diversity at non-MHC loci (d²) in both contexts. Importantly, these findings provide further support for a special role of the MHC in human sexual selection and suggest that male and female mate preferences may work together to potentially enhance both male and female reproductive success by increasing genetic diversity in offspring.     

The Influence of Learning on Host Plant Preference in a Significant Phytopathogen Vector,Diaphorina citri

Although specialist herbivorous insects are guided by innate responses to host plant cues, host plant preference may be influenced by experience and is not dictated by instinct alone. The effect of learning on host plant preference was examined in the Asian citrus psyllid, Diaphorina citri; vector of the causal agent of citrus greening disease or huanglongbing. We investigated: a) whether development on specific host plant species influenced host plant preference in mature D. citri; and b) the extent of associative learning in D. citri in the form of simple and compound conditioning. Learning was measured by cue selection in a 2-choice behavioral assay and compared to naïve controls. Our results showed that learned responses in D. citri are complex and diverse. The developmental host plant species influenced adult host plant preference, with female psyllids preferring the species on which they were reared. However, such preferences were subject to change with the introduction of an alternative host plant within 24–48 hrs, indicating a large degree of experience-dependent response plasticity. Additionally, learning occurred for multiple sensory modalities where novel olfactory and visual environmental cues were associated with the host plant. However, males and females displayed differing discriminatory abilities. In compound conditioning tasks, males exhibited recognition of a compound stimulus alone while females were capable of learning the individual components. These findings suggest D. citri are dynamic animals that demonstrate host plant preference based on developmental and adult experience and can learn to recognize olfactory and visual host plant stimuli in ways that may be sex specific. These experience-based associations are likely used by adults to locate and select suitable host plants for feeding and reproduction and may suggest the need for more tailored lures and traps, which reflect region-specific cultivars or predominate Rutaceae in the area being monitored.     

Affective Balance,Team Prosocial Efficacy and Team Trust: A Multilevel Analysis of Prosocial Behavior in Small Groups

Little research has focused on how individual- and team-level characteristics jointly influence, via interaction, how prosocially individuals behave in teams and few studies have considered the potential influence of team context on prosocial behavior. Using a multilevel perspective, we examined the relationships between individual (affective balance) and group (team prosocial efficacy and team trust) level variables and prosocial behavior towards team members. The participants were 123 students nested in 45 small teams. A series of multilevel random models was estimated using hierarchical linear and nonlinear modeling. Individuals were more likely to behave prosocially towards in-group members when they were feeling good. Furthermore, the relationship between positive affective balance and prosocial behavior was stronger in teams with higher team prosocial efficacy levels as well as in teams with higher team trust levels. Finally, the relevance of team trust had a stronger influence on behavior than team prosocial efficacy.     

The feeding height preferences of two goat breeds fed Grewia occidentalis L. (Tiliaceae) in the Eastern Cape,South Africa

Nguni goats and Boer goats, which are farmed together in the savannas of the Eastern Cape Province, depend on the same feed resources. The feeding height intake rates and preferences of one of their most preferred browse species, Grewia occidentalis L. (Tiliaceae), were studied in order to indirectly determine resource partitioning between these goat breeds on the basis of feeding height. The two hypotheses tested were that taller Boer goats feed at higher levels than do Nguni goats and that both breeds have feeding height preferences that are related to differences in intake rates. Four individuals of each breed were fed branches attached to a height foraging board. The two breeds showed no particular height preference in either season. Bite rates varied with feeding height, while bite sizes and intake rates increased with feeding height. Boer goats had lower bite rates compared to Nguni goats, although both breeds achieved similar bite sizes and intake rates. Bites sizes and intake rates for both breeds were higher in summer than in winter, possibly because more browse biomass was available per branch in summer than in winter since G. occidentalis is deciduous. There was no evidence to support that feeding height preference was related to differences in intake rates. It is concluded that Boer goats may compete for forage resources during times of resource limitation. Thus, Nguni goats might be a more favourable breed in semi-arid savannas because of their smaller body-size and, therefore, absolute nutrient requirements as well as their better reproductive performance compared to Boer goats.     

Emotion Regulation Moderates the Association between Empathy and Prosocial Behavior

Theory and evidence suggest that empathy is an important motivating factor for prosocial behaviour and that emotion regulation, i.e. the capacity to exert control over an emotional response, may moderate the degree to which empathy is associated with prosocial behaviour. However, studies to date have not simultaneously explored the associations between different empathic processes and prosocial behaviour, nor whether different types of emotion regulation strategies (e.g. cognitive reappraisal and expressive suppression) moderate associations between empathy and prosocial behaviour. One hundred–and-ten healthy adults completed questionnaire measures of empathy, emotion regulation and prosocial tendencies. In this sample, both affective and cognitive empathy predicted self-reported prosocial tendencies. In addition, cognitive reappraisal moderated the association between affective empathy and prosocial tendencies. Specifically, there was a significant positive association between empathy and prosocial tendencies for individuals with a low or average tendency to reappraise but not for those with a high tendency to reappraise. Our findings suggest that, in general, empathy is positively associated with prosocial behaviour. However, this association is not significant for individuals with a high tendency for cognitive reappraisal.     

Hand preferences on unimanual and bimanual tasks in Tonkean macaques (Macaca tonkeana)

This is the first study to examine hand preferences in Tonkean macaques on a bimanual task. One of our objectives was to continue the move toward greater task standardization, in order to facilitate comparisons between species and studies on handedness. The main aim was to test and determine task robustness, by varying intra‐task complexity. To this end, we administered several different tasks to the subjects: two unimanual tasks (grasping task featuring items of different sizes) and three coordinated bimanual tasks (tube task involving different materials, weights, and diameters). Although we found no significant hand preference in either task at the group level, the macaques were more strongly lateralized for small items than for large ones in the unimanual grasping task. Moreover, the absence of a correlation between these two versions of the unimanual task confirmed the weakness of this grasping task for assessing handedness. Regarding the bimanual tube task, no difference was found between the three versions in either the direction or the strength of hand preference. Moreover, the highly correlated hand preferences between these three versions suggest that the tube task provides a more robust means of measuring manual preferences. Am J Phys Anthropol 152:315–321, 2013. © 2013 Wiley Periodicals, Inc.     

Monkeys Are More Patient in a Foraging Task than in a Standard Intertemporal Choice Task

Studies of animal impulsivity generally find steep subjective devaluation, or discounting, of delayed rewards – often on the order of a 50% reduction in value in a few seconds. Because such steep discounting is highly disfavored in evolutionary models of time preference, we hypothesize that discounting tasks provide a poor measure of animals’ true time preferences. One prediction of this hypothesis is that estimates of time preferences based on these tasks will lack external validity, i.e. fail to predict time preferences in other contexts. We examined choices made by four rhesus monkeys in a computerized patch-leaving foraging task interleaved with a standard intertemporal choice task. Monkeys were significantly more patient in the foraging task than in the intertemporal choice task. Patch-leaving behavior was well fit by parameter-free optimal foraging equations but poorly fit by the hyperbolic discount parameter obtained from the intertemporal choice task. Day-to-day variation in time preferences across the two tasks was uncorrelated with each other. These data are consistent with the conjecture that seemingly impulsive behavior in animals is an artifact of their difficulty understanding the structure of intertemporal choice tasks, and support the idea that animals are more efficient rate maximizers in the multi-second range than intertemporal choice tasks would suggest.     

Exploring Empathic Space: Correlates of Perspective Transformation Ability and Biases in Spatial Attention

Separate lines of research have noted recruitment of parietal cortex during tasks involving visuo-spatial processes and empathy. To explore the relationship between these two functions, a self-other perspective transformation task and a task of spatial attention (line bisection) were administered to 40 healthy participants (19 women). Performance on these tasks was examined in relation to self-reported empathy. Rightward biases in line bisection correlated positively with trait-level self-reported empathic concern, suggesting a left hemisphere mediation of this prosocial personality trait. Unexpectedly, speed of perspective taking in the self-other transformation task correlated negatively with empathic concern, but only in women, which we interpret in light of gender differences in empathy and strategies for egocentric mental transformations. Together, the findings partially support the commonalities in visuo-spatial attention, perspective-taking and empathy. More broadly, they shed additional light on the relationship between basic cognitive functions and complex social constructs.     

Familiarity and partner preferences in female common voles, <Emphasis Type="Italic">Microtus arvalis</Emphasis>

Captive female common voles (Microtus arvalis) had a clear social preference for familiar males in a standard preference test. Cohabitation for a short period resulted in preferences for familiar partners, and females spent eight times more time in body contact with a familiar male than with an unfamiliar male. Females also displayed stranger-directed aggression. Our results suggest that the common vole is a species with selective partner preferences and a tendency to form tight social relationships and stable male–female associations.     

Plasma progesterone levels in superovulated cattle in relation to hatched embryo sizes,ovulation rates,and premature regression of corpora lutea

Progesterone concentrations were measured in peripheral plasma of 62 cattle treated with PMSG. There was good correlation (r = 0.92) between a single day-10 value and the sum of daily values up to day 12 (19 animals) or day 13 (17 animals). The day-10 progesterone level was correlated strongly with ovulation rate (r = 0.76; 55 animals) but to a negligible extent with the sizes of 306 day-13 embryos from 47 donors (r = 0.17). Premature regression of corpora lutea, encountered in 14 (7.3%) of 191 flushed donors, began between days 5 and 8 and was reflected in the progesterone profiles of seven animals that were serially sampled.     

Consistency of hand preference across low-level and high-level tasks in capuchin monkeys (Cebus apella)

Numerous studies investigating behavioral lateralization in capuchins have been published. Although some research groups have reported a population-level hand preference, other researchers have argued that capuchins do not show hand preference at the population level. As task complexity influences the expression of handedness in other primate species, the purpose of this study was to collect hand preference data across a variety of high- and low-level tasks to evaluate how task complexity influences the expression of hand preference in capuchins. We tested eleven captive brown capuchin monkeys (Cebus apella) to determine if they show consistent hand preferences across multiple high- and low-level tasks. Capuchins were expected to display high intertask consistency across the high-level tasks but not the low-level tasks. Although most individuals showed significant hand preferences for each task, only two of the high-level tasks that involved similar hand motions were significantly positively correlated, indicating consistency of hand preference across these tasks only. None of the tasks elicited a group-level hand preference. High-level tasks elicited a greater strength of hand preference than did low-level tasks. No sex differences were found for the direction or strength of hand preference for any task. These results contribute to the growing database of primate laterality and provide additional evidence that capuchins do not display group-level hand preferences.     

Associations of Quality of Life with Service Satisfaction in Psychotic Patients: A Meta-Analysis

Background

Quality of life (QoL) has gained increasing attention as a desired outcome of psychosocial treatments targeting psychotic patients. Yet, the relationship between the patients’ satisfaction with services and QoL has not been clearly established, perhaps due to the multidimensionality of the QoL concept and the variability in its assessment.

Aim

This is the first systematic meta-analysis of all available evidence assessing the relationship between QoL and service satisfaction. Methods: In all, 19 studies reporting data of 21 independent samples (N = 5,337) were included in the present meta-analysis. In moderator analyses, effects of age, sex, diagnoses (schizophrenia vs. other psychoses), treatment context (inpatients vs. outpatients), study design (cross-sectional vs. longitudinal), and QoL domain (subjective vs. health-related) were examined.

Results

Analyses revealed a highly significant medium-sized effect (r = .30, p < .001) for the associations of QoL and service satisfaction. Effect sizes were significantly stronger for subjective than health-related quality of life (r = .35 vs. r = .14, respectively). Moreover, associations with subjective QoL remained largely robust when accounting for moderating variables, although there was a trend of stronger associations for outpatients compared to inpatients. In contrast, effect sizes for health-related QoL were small and only observable for samples with longitudinal designs.

Conclusion

Associations between QoL and service satisfaction appear to be robust but are differentiated in regard to QoL domain. Our findings suggest that agents responsible for service design and implementation need to take the patients’ perception of the service adequacy for achieving QoL enhancement into account.     

Left Preference for Sport Tasks Does Not Necessarily Indicate Left-Handedness: Sport-Specific Lateral Preferences,Relationship with Handedness and Implications for Laterality Research in Behavioural Sciences

In the elite domain of interactive sports, athletes who demonstrate a left preference (e.g., holding a weapon with the left hand in fencing or boxing in a ‘southpaw’ stance) seem overrepresented. Such excess indicates a performance advantage and was also interpreted as evidence in favour of frequency-dependent selection mechanisms to explain the maintenance of left-handedness in humans. To test for an overrepresentation, the incidence of athletes'' lateral preferences is typically compared with an expected ratio of left- to right-handedness in the normal population. However, the normal population reference values did not always relate to the sport-specific tasks of interest, which may limit the validity of reports of an excess of ‘left-oriented’ athletes. Here we sought to determine lateral preferences for various sport-specific tasks (e.g., baseball batting, boxing) in the normal population and to examine the relationship between these preferences and handedness. To this end, we asked 903 participants to indicate their lateral preferences for sport-specific and common tasks using a paper-based questionnaire. Lateral preferences varied considerably across the different sport tasks and we found high variation in the relationship between those preferences and handedness. In contrast to unimanual tasks (e.g., fencing or throwing), for bimanually controlled actions such as baseball batting, shooting in ice hockey or boxing the incidence of left preferences was considerably higher than expected from the proportion of left-handedness in the normal population and the relationship with handedness was relatively low. We conclude that (i) task-specific reference values are mandatory for reliably testing for an excess of athletes with a left preference, (ii) the term ‘handedness’ should be more cautiously used within the context of sport-related laterality research and (iii) observation of lateral preferences in sports may be of limited suitability for the verification of evolutionary theories of handedness.     

Local and Global Limits on Visual Processing in Schizophrenia

Schizophrenia has been linked to impaired performance on a range of visual processing tasks (e.g. detection of coherent motion and contour detection). It has been proposed that this is due to a general inability to integrate visual information at a global level. To test this theory, we assessed the performance of people with schizophrenia on a battery of tasks designed to probe voluntary averaging in different visual domains. Twenty-three outpatients with schizophrenia (mean age: 40±8 years; 3 female) and 20 age-matched control participants (mean age 39±9 years; 3 female) performed a motion coherence task and three equivalent noise (averaging) tasks, the latter allowing independent quantification of local and global limits on visual processing of motion, orientation and size. All performance measures were indistinguishable between the two groups (ps>0.05, one-way ANCOVAs), with one exception: participants with schizophrenia pooled fewer estimates of local orientation than controls when estimating average orientation (p = 0.01, one-way ANCOVA). These data do not support the notion of a generalised visual integration deficit in schizophrenia. Instead, they suggest that distinct visual dimensions are differentially affected in schizophrenia, with a specific impairment in the integration of visual orientation information.     

Oxytocin and pair compatibility in adult male rhesus macaques (Macaca mulatta)

Pair housing is considered one of the best ways of promoting psychological wellbeing for caged macaques. However, incompatible partnerships can result in stress or aggression. Though previous studies have analyzed the role of variables such as age, weight, gender, and temperament on pair compatibility, few have examined the relationship between physiological parameters and pair compatibility. Oxytocin is known to promote prosocial nonsexual behavior in various primate species and may serve as an indicator of pair compatibility. In this study, we examined the association between peripheral oxytocin levels and prosocial behaviors in isosexual pairs of male rhesus macaques. We hypothesized that animals that demonstrated high levels of prosocial behaviors would have higher oxytocin levels than those showing low levels of the behavior. In addition, to elucidate the relationship between oxytocin and compatibility, we compared peripheral oxytocin between the highly affiliative animals and single‐housed males identified as having multiple unsuccessful pair attempts with multiple partners. We collected plasma oxytocin on 40 pairs of monkeys that had lived together for at least 1 month and 20 single‐housed animals. Further, we simultaneously collected behavioral data on the pairs, recording prosocial interactions (e.g., groom, play). Oxytocin varied among individuals, but was highly correlated between members of a pair (r = 0.58, p < .001). Additionally, prosocial behavior was positively correlated with plasma oxytocin (r = 0.38, p < .02). However, contrary to our expectations, oxytocin did not differ between single and highly affiliative pair‐housed animals (F_(1,38) = 0.71, p = .40). Our results suggest that oxytocin may be associated with the quality of isosexual pairs of male macaques. More work is needed to determine the nature of this relationship.