Mental health of veterinary nurses and student veterinary nurses: A scoping review.

BACKGROUND: Research has shown that veterinarians around the world are at high risk of mental health problems, but far less research has examined the mental health of veterinary nurses (VNs) and student veterinary nurses (SVNs). This scoping review aimed to map existing evidence on this topic and identify knowledge gaps. METHODS: Literature searches of MEDLINE, PsycINFO, PubMed, Web of Science and Google Scholar were conducted, and a structured screening and selection procedure was applied. To be included, studies had to be peer reviewed, report relevant results specific to VNs and/or SVNs, and provide descriptive statistics if using quantitative methods. RESULTS: Of the 2118 publications identified, only 13 journal articles met the inclusion criteria. The findings were summarised in five categories: mental health and wellbeing, burnout, stress, compassion fatigue and moral distress. While the findings of five of the studies suggested that some VNs and SVNs experienced some form of poor mental health, these studies lacked generalisability or transferability for multiple reasons. There was also inconsistency and ambiguity in the interpretation of findings, as well as incompatible or oversimplified definitions of mental health problems. LIMITATIONS: Our review excluded grey literature, such as reports, theses and conference presentations, as a preliminary search found very little empirical research on VNs' and SVNs' mental health in this type of publication. CONCLUSIONS: More research is needed to address the gaps in the existing evidence supporting our understanding of VN and SVN mental health. This should establish baseline measures and include comparisons with other occupational and national populations.

Working memory and attention in choice.

We study the role of attention and working memory in choices where options are presented sequentially rather than simultaneously. We build a model where a costly attention effort is chosen, which can vary over time. Evidence is accumulated proportionally to this effort and the utility of the reward. Crucially, the evidence accumulated decays over time. Optimal attention allocation maximizes expected utility from final choice; the optimal solution takes the decay into account, so attention is preferentially devoted to later times; but convexity of the flow attention cost prevents it from being concentrated near the end. We test this model with a choice experiment where participants observe sequentially two options. In our data the option presented first is, everything else being equal, significantly less likely to be chosen. This recency effect has a natural explanation with appropriate parameter values in our model of leaky evidence accumulation, where the decline is stronger for the option observed first. Analysis of choice, response time and brain imaging data provide support for the model. Working memory plays an essential role. The recency bias is stronger for participants with weaker performance in working memory tasks. Also activity in parietal areas, coding the stored value in working, declines over time as predicted.

Shotgun Metagenomic Sequencing Revealed the Prebiotic Potential of a Fruit Juice Drink with Fermentable Fibres in Healthy Humans.

Fibre-based dietary interventions are at the forefront of gut microbiome modulation research, with a wealth of 16S rRNA information to demonstrate the prebiotic effects of isolated fibres. However, there is a distinct lack of data relating to the effect of a combination of soluble and insoluble fibres in a convenient-to-consume fruit juice food matrix on gut microbiota structure, diversity, and function. Here, we aimed to determine the impact of the MOJU Prebiotic Shot, an apple, lemon, ginger, and raspberry fruit juice drink blend containing chicory inulin, baobab, golden kiwi, and green banana powders, on gut microbiota structure and function. Healthy adults (n = 20) were included in a randomised, double-blind, placebo-controlled, cross-over study, receiving 60 mL MOJU Prebiotic Shot or placebo (without the fibre mix) for 3 weeks with a 3-week washout period between interventions. Shotgun metagenomics revealed significant between-group differences in alpha and beta diversity. In addition, the relative abundance of the phyla Actinobacteria and Desulfobacteria was significantly increased as a result of the prebiotic intervention. Nine species were observed to be differentially abundant (uncorrected p-value of <0.05) as a result of the prebiotic treatment. Of these, Bifidobacterium adolescentis and CAG-81 sp900066785 (Lachnospiraceae) were present at increased abundance relative to baseline. Additionally, KEGG analysis showed an increased abundance in pathways associated with arginine biosynthesis and phenylacetate degradation during the prebiotic treatment. Our results show the effects of the daily consumption of 60 mL MOJU Prebiotic Shot for 3 weeks and provide insight into the functional potential of B. adolescentis.

How perceived scarcity predicted cooperation during early pandemic lockdown.

Both material resources (jobs, healthcare), and socio-psychological resources (social contact) decreased during the COVID-19 pandemic. We investigated whether individual differences in perceived material and socio-psychological scarcity experienced during the pandemic predicted preference for cooperation, measured using two Public Good Games (PGGs), where participants contributed money or time (i.e., hours indoors contributed to shorten the lockdown). Material scarcity had no relationship with cooperation. Increased perceived scarcity of socio-psychological wellbeing (e.g., connecting with family) predicted increased preference for cooperation, suggesting that missing social contact fosters prosociality, whilst perceived scarcity of freedom (e.g., limited movement) predicted decreased willingness to spend time indoors to shorten the lockdown. The importance of considering individual differences in scarcity perception to best promote norm compliance is discussed.

Does unfairness sound wrong? A cross-domain investigation of expectations in music and social decision-making.

This study was interested in investigating the existence of a shared psychological mechanism for the processing of expectations across domains. The literature on music and language shows that violations of expectations produce similar neural responses and violating the expectation in one domain may influence the processing of stimuli in the other domain. Like music and language, our social world is governed by a system of inherent rules or norms, such as fairness. The study therefore aimed to draw a parallel to the social domain and investigate whether a manipulation of melodic expectation can influence the processing of higher-level expectations of fairness. Specifically, we aimed to investigate whether the presence of an unexpected melody enhances or reduces participants' sensitivity to the violations of fairness and the behavioural reactions associated with these. We embedded a manipulation of melodic expectation within a social decision-making paradigm, whereby musically expected and unexpected stimuli will be simultaneously presented with fair and unfair divisions in a third-party altruistic punishment game. Behavioural and electroencephalographic responses were recorded. Results from the pre-planned analyses show that participants are less likely to punish when melodies are more unexpected and that violations of fairness norms elicit medial frontal negativity (MFN)-life effects. Because no significant interactions between melodic expectancy and fairness of the division were found, results fail to provide evidence of a shared mechanism for the processing of expectations. Exploratory analyses show two additional effects: (i) unfair divisions elicit an early attentional component (P2), probably associated with stimulus saliency, and (ii) mid-value divisions elicit a late MFN-like component, probably reflecting stimulus ambiguity. Future studies could build on these results to further investigate the effect of the cross-domain influence of music on the processing of social stimuli on these early and late components.

Neurocognitive mechanisms of reactions to second- and third-party justice violations.

The aim of the current study was threefold: (i) understand people's willingness to engage in either punishment of the perpetrator or compensation of the victim in order to counteract injustice; (ii) look into the differences between victims of and witnesses to injustice; (iii) investigate the different role played by social preference and affective experience in determining these choices. The sample tested here showed an equal preference for punishment and compensation; neuroimaging findings suggested that compensation, as opposed to punishment, was related to Theory of Mind. Partially supporting previous literature, choosing how to react to an injustice as victims, rather than witnesses, triggered a stronger affective response (striatal and prefrontal activation). Moreover, results supported the idea that deciding whether or not to react to an injustice and then how severely to react are two distinct decisional stages underpinned by different neurocognitive mechanisms, i.e., sensitivity to unfairness (anterior insula) and negative affectivity (amygdala). These findings provide a fine-grained description of the psychological mechanisms underlying important aspects of social norm compliance.

A scarcity mindset alters neural processing underlying consumer decision making.

Not having enough of what one needs has long been shown to have detrimental consequences for decision making. Recent work suggests that the experience of insufficient resources can create a "scarcity" mindset; increasing attention toward the scarce resource itself, but at the cost of attention for unrelated aspects. To investigate the effects of a scarcity mindset on consumer choice behavior, as well as its underlying neural mechanisms, we used an experimental manipulation to induce both a scarcity and an abundance mindset within participants and examined the effects of both mindsets on participants' willingness to pay for familiar food items while being scanned using fMRI. Results demonstrated that a scarcity mindset affects neural mechanisms related to consumer decision making. When in a scarcity mindset compared with an abundance mindset, participants had increased activity in the orbitofrontal cortex, a region often implicated in valuation processes. Moreover, again compared with abundance, a scarcity mindset decreased activity in dorsolateral prefrontal cortex, an area well known for its role in goal-directed choice. This effect was predominant in the group of participants who experienced scarcity following abundance, suggesting that the effects of scarcity are largest when they are compared with previous situations when resources were plentiful. More broadly, these data suggest a potential neural locus for a scarcity mindset and demonstrate how these changes in brain activity might underlie goal-directed decision making.

Predicting the other in cooperative interactions.

Recent research has shown that a collection of neurons in dorsal anterior cingulate cortex of rhesus monkeys may specifically encode the choice selection of an interaction partner. This raises interesting and important questions as to the nature of Theory of Mind processes in social interactive decision-making, with potential societal implications.

Medial prefrontal cortex reacts to unfairness if this damages the self: a tDCS study.

Neural correlates of unfairness perception depend on who is the target of the unfair treatment. These previous findings suggest that the activation of medial prefrontal cortex (MPFC) is related to unfairness perception only when the subject of the measurement is also the person affected by the unfair treatment. We aim at demonstrating the specificity of MPFC involvement using transcranial direct current stimulation (tDCS), a technique that induces cortical excitability changes in the targeted region. We use a modified version of the Ultimatum Game, in which responders play both for themselves (myself-MS condition) and on behalf of an unknown third-party (TP condition), where they respond to unfairness without being the target of it. We find that the application of cathodal tDCS over MPFC decreases the probability of rejecting unfair offers in MS, but not in TP; conversely, the same stimulation increases the probability of rejecting fair offers in TP, but not in MS. We confirm the hypothesis that MPFC is specifically related to processing unfairness when the self is involved, and discuss possible explanations for the opposite effect of the stimulation in TP.

Framing the ultimatum game: the contribution of simulation.

It has now become widely accepted that economic decisions are influenced by cognitive and emotional processes. In the present study, we aimed at disentangling the neural mechanisms associated with the way in which the information is formulated, i.e., framing effect, in terms of gain or loss, which influences people's decisions. Participants played a fMRI version of the Ultimatum Game (UG) where we manipulated bids through two different frames: the expression "I give you" (gain) focusing on money the respondent would receive if she/he agreed with the proponent, and the expression "I take" (loss) focusing on the money that would be removed from the respondent in the event that she/he accepted the offer. Neuroimaging data revealed a frame by response interaction, showing an increase of neural activity in the right rolandic operculum/insular cortex, the anterior cingulate, among other regions, for accepting the frame "I take" vs. rejecting, as compared to accepting the frame "I give you" vs. rejecting. In addition, the left occipito-temporal junction was activated for "I take" vs. "I give you" for offer 5, corresponding to the equal offer made unpleasant by the presence of the frame "I take," where is the proposer that takes the money. Our data extend the current understanding of the neural substrates of social decision making, by disentangling the structures sensitive to the way in which the information is formulated (i.e., framing effect), in terms of gain or loss.

More equal than others: Equity norms as an integration of cognitive heuristics and contextual cues in bargaining games.

Behavior in one-shot bargaining games, like the Ultimatum Game (UG), has been interpreted as an expression of social preferences, such as inequity aversion and negative reciprocity; however, the traditional UG design limits the range of possible psychological interpretation of the results. Here, we employed three different designs for ultimatum games, finding support for a more comprehensive theory: behavior is driven by cognitive factors implementing rules such as equal splitting, speaking up for the idea that equity works as a cognitive heuristic, applicable when the environment provides no reason to behave otherwise. Instead subjects deviate from this rule when environment changes, as, for instance, when personal interest is at stake. Results show that behavior varies systematically with contextual cues, balancing the self-interest with the automatic application of the equity heuristic. Thus, the context suggests the rule to be applied in a specific situation.

Disentangling self- and fairness-related neural mechanisms involved in the ultimatum game: an fMRI study.

Rejections of unfair offers in the ultimatum game (UG) are commonly assumed to reflect negative emotional arousal mediated by the anterior insula and medial prefrontal cortex. We aimed to disentangle those neural mechanisms associated with direct personal involvement ('I have been treated unfairly') from those associated with fairness considerations, such as the wish to discourage unfair behavior or social norm violations ('this person has been treated unfairly'). For this purpose, we used fMRI and asked participants to play the UG as responders either for themselves (myself) or on behalf of another person (third party). Unfair offers were equally often rejected in both conditions. Neuroimaging data revealed a dissociation between the medial prefrontal cortex, specifically associated with rejections in the myself condition, thus confirming its role in self-related emotional responses, and the left anterior insula, associated with rejections in both myself and third-party conditions, suggesting a role in promoting fair behavior also toward third parties. Our data extend the current understanding of the neural substrate of social decision making, by disentangling the structures sensitive to direct emotional involvement of the self from those implicated in pure fairness considerations.

Equality versus self-interest in the brain: differential roles of anterior insula and medial prefrontal cortex.

Everything else being the same, an equal outcome is generally preferred; however, an equitable allocation sometimes is possible only by sacrificing the total amount of resources available to society. Moreover, direct interests may interact with the perception of equality. Here, we have investigated individual preferences, and their neural basis, by employing a task in which an allocation of a fixed amount between the subject and another person (MS condition) or two third parties (TP condition) is randomly determined. The subject can accept or reject the outcome, in the same fashion as the Ultimatum Game: thus an unequal offer may be rejected at the cost of a loss in total amount. Behavioral results show preference for equal outcomes in TP and for equal and advantageous outcomes in MS. An activation of medial prefrontal cortex (mPFC), extending to the anterior middle cingulate cortex (aMCC), was found in MS unequal outcomes, particularly for disadvantageous outcomes and consequent rejections. The anterior insula (AI) was active for unequal outcomes, in both MS and TP. We propose that the equal treatment is a default social norm, and its violation is signaled by the AI, whereas aMCC/mPFC activation, negatively correlated to rejections, reflects the effort to overcome the default rule of equal treatment in favor of a self-advantageous efficiency.

In medio stat virtus: theoretical and methodological extremes regarding reciprocity will not explain complex social behaviors.

Guala contests the validity of strong reciprocity as a key element in shaping social behavior by contrasting evidence from experimental games to that of natural and historic data. He suggests that in order to understand the evolution of social behavior researchers should focus on natural data and weak reciprocity. We disagree with Guala's proposal to shift the focus of the study from one extreme of the spectrum (strong reciprocity) to the other extreme (weak reciprocity). We argue that the study of the evolution of social behavior must be comparative in nature, and we point out experimental evidence that shows that social behavior is not cooperation determined by a set of fixed factors. We argue for a model that sees social behavior as a dynamic interaction of genetic and environmental factors.

Are irrational reactions to unfairness truly emotionally-driven? Dissociated behavioural and emotional responses in the Ultimatum Game task.

The "irrational" rejections of unfair offers by people playing the Ultimatum Game (UG), a widely used laboratory model of economical decision-making, have traditionally been associated with negative emotions, such as frustration, elicited by unfairness (Sanfey, Rilling, Aronson, Nystrom, & Cohen, 2003; van't Wout, Kahn, Sanfey, & Aleman, 2006). We recorded skin conductance responses as a measure of emotional activation while participants performed a modified version of the UG, in which they were asked to play both for themselves and on behalf of a third-party. Our findings show that even unfair offers are rejected when participants' payoff is not affected (third-party condition); however, they show an increase in the emotional activation specifically when they are rejecting offers directed towards themselves (myself condition). These results suggest that theories emphasizing negative emotions as the critical factor of "irrational" rejections (Pillutla & Murninghan, 1996) should be re-discussed. Psychological mechanisms other than emotions might be better candidates for explaining this behaviour.

Mentalizing in economic decision-making.

In the Ultimatum Game, participants typically reject monetary offers they consider unfair even if the alternative is to gain no money at all. In the present study, ERPs were recorded while subjects processed different offers of a proposer. In addition to clearly fair and unfair offers, mid-value offers which cannot be easily classified as fair or unfair and therefore involve more elaborate decision making were analyzed. A fast initial distinction between fair and other kinds of offers was reflected by amplitude of the feedback related negativity (FRN). Mid-value offers were associated with longer RTs, and a larger N350 amplitude. In addition, source analyses revealed a specific involvement of the superior temporal gyrus and the inferior parietal lobule during processing of mid-value offers compared to offers categorized clearly as fair or unfair, suggesting a contribution of mentalizing about the intention of the proposer to the decision making process. Taken together, the present findings support the idea that economic decisions are significantly affected by non-rational factors, trying to narrow the gap between formal theory and the real decisional behaviour.