Child Temperament and Early Childhood Caries: A Systematic Review and Meta-Analysis.

Purpose: The purpose of this study was to perform a systematic review to assess current evidence for the association between child temperament and early childhood caries (ECC). Methods: A systematic search was conducted using MEDLINE?? through PubMed®, EMBASE®, Scopus®, LILACS, Web of Science™, and EBSCO up to January 2023. Studies measuring ECC and child temperament for children younger than or equal to six years of age using questionnaires, interviews, and surveys through case-control studies, cohort studies, and cross-sectional studies were included. Literature reviews were excluded. Medical subject heading (MeSH) terms like "temperament" and "dental caries" were used by two authors who independently extracted the data, and a third author resolved disagreements. Risk of bias assessment was done using the Newcastle-Ottawa assessment scale for case-control and cohort studies and the Appraisal tool for Cross-Sectional Studies (AXIS). The quality of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluations approach (GRADE approach). A chi-square test and I-square index were used to evaluate heterogeneity. Results: A total of 5,072 records were screened, resulting in 15 included studies that yielded data for 6,667 participants; sevenstudies were high, and eight were of moderate quality. Seven studies qualified for meta-analysis, which revealed that persistence did not affectthe presence or absence of ECC. However, there was a strong association between difficult temperament and ECC (odds ratio equals 2.63). Conclusion: A positive association between a child???s temperament and early childhood caries exists that is supported by quantitative findings, indicating a connection with very low certainty.

Profiles and the impact of affective temperaments on alcohol use disorder: a cross-sectional study.

AIMS: This study aimed to explore the profiles and impact of affective temperaments, together with social and clinical backgrounds, including affective symptoms, in patients with alcohol use disorder (AUD). METHODS: This study included 314 low-risk drinkers and 257 patients with AUD. To assess affective temperament, we used the short version of the temperament evaluation of Memphis, Pisa, Paris, and San Diego. To evaluate depressive and mixed symptoms, the quick inventory of depressive symptomatology self-report Japanese version and 12-item questionnaire for the quantitative assessment of the depressive mixed state were used. We compared the profiles of affective temperaments as well as social and clinical backgrounds, including affective symptoms, between the two groups and further performed logistic regression analyses to explore the factors contributing to AUD. RESULTS: Our analysis showed higher cyclothymic, hyperthymic, and irritable temperament scores and lower depressive temperament scores in patients with AUD than that in nonclinical drinkers. Regarding other social and clinical backgrounds, patients with AUD were less educated and employed and more experienced depressive and mixed symptoms. Logistic regression analysis identified hyperthymic temperament as a positive contributor and depressive temperament as a negative contributor to AUD. CONCLUSIONS: Our findings indicated potential bipolarity in patients with AUD, as manifested by a more hyperthymic temperament in contrast to less depressive temperament. Despite their self-perceived adaptive temperament profiles, patients showed poorer social outcomes and more affective symptoms. This gap may be partly explained by a lack of insight unique to AUD psychology, which potentially disturbs problem recognition.

Adherence to dietary recommendations mediates the effect of affective temperaments on infertility treatment outcomes.

Affective temperaments have been shown to robustly affect infertility treatment success. However, identification of possible mediating factors through which they exert their influence is still lacking. A growing number of results suggest that adherence to recommended treatments may be such a mediator, on the one hand, because affective temperaments are known to influence adherence and, on the other hand, because non-adherence negatively influences the treatment outcome. Recommended treatment of infertility involves, beyond medications, dietary and lifestyle changes. The aim of this retrospective cohort study was to evaluate whether adherence to physician-prescribed diet and physical activity recommendations mediates the effect of affective temperaments on infertility treatment outcomes. Among 308 women who underwent infertility treatment in an Assisted Reproduction Center, affective temperaments, adherence to diet, adherence to physical exercise, and infertility treatment success (clinical pregnancy) were assessed besides detailed medical history and demographic parameters. Associations between affective temperaments, adherence to diet and recommended physical activity, and assisted reproduction outcomes were analyzed using generalized linear models and causal mediation analysis. Adherence to physical activity didn't have an effect, but diet adherence increased the odds of infertility treatment success by 130% suggesting its role as a potential mediator. Based on causal mediation analysis, higher depressive and anxious temperament scores were directly associated with 63% and 45% lower odds of achieving clinical pregnancy, respectively, with effects not mediated by diet adherence. Higher irritable temperament scores indirectly decreased the odds of achieving clinical pregnancy by 14%, mediated by diet adherence; while higher cyclothymic temperament scores decreased the odds of achieving clinical pregnancy both directly by 51% and indirectly, mediated by diet adherence by 11%. Our results suggest that diet adherence mediates the mechanism by which irritable and cyclothymic affective temperaments influence IVF treatment success. Since adherence is a modifiable risk factor of infertility treatment success, screening for affective temperaments may help to identify potentially high-risk non-adherent patient groups and offer patient-tailored treatment, which may help increase the chances of a successful pregnancy and live birth in women undergoing IVF treatment.

Neural and psychological correlates of post-traumatic stress symptoms in a community adult sample.

A multitude of factors are associated with the symptoms of post-traumatic stress disorder. However, establishing which predictors are most strongly associated with post-traumatic stress disorder symptoms is complicated because few studies are able to consider multiple factors simultaneously across the biopsychosocial domains that are implicated by existing theoretical models. Further, post-traumatic stress disorder is heterogeneous, and studies using case-control designs may obscure which factors relate uniquely to symptom dimensions. Here we used Bayesian variable selection to identify the most important predictors for overall post-traumatic stress disorder symptoms and individual symptom dimensions in a community sample of 569 adults (18 to 85 yr of age). Candidate predictors were selected from previously established risk factors relevant for post-traumatic stress disorder and included psychological measures, behavioral measures, and resting state functional connectivity among brain regions. In a follow-up analysis, we compared results controlling for current depression symptoms in order to examine specificity. Poor sleep quality and dimensions of temperament and impulsivity were consistently associated with greater post-traumatic stress disorder symptom severity. In addition to self-report measures, brain functional connectivity among regions commonly ascribed to the default mode network, central executive network, and salience network explained the unique variability of post-traumatic stress disorder symptoms. This study demonstrates the unique contributions of psychological measures and neural substrates to post-traumatic stress disorder symptoms.

Comprendiendo el temperamento difícil en adultos: un estudio de métodos mixtos / Understanding difficult temperament in adults: a mixed methods study

El temperamento difícil es un conjunto de características conductuales asociadas a la salud mental y un predictor significativo de psicopatología. El objetivo de este estudio era investigar qué características temperamentales pueden considerarse atributos del temperamento difícil en adultos lituanos. La muestra consistió en 429 adultos de entre 18 y 79 años de edad. Se utilizó el “Cuestionario de temperamento adulto” para evaluar las características temperamentales y el temperamento difícil percibido. Los datos se analizaron mediante un enfoque de métodos mixtos. Los resultados mostraron que el conjunto de atributos percibidos como constitutivos del temperamento difícil incluye características como el estado de ánimo negativo, la intensidad de las reacciones emocionales, la baja adaptabilidad, el retraimiento y la baja regularidad. El análisis de los datos cuantitativos reveló una inesperada relación negativa entre el temperamento difícil percibido y la característica de ritmicidad, mientras que en los datos cualitativos surgió una nueva categoría de terquedad. Estos hallazgos aportan nuevos conocimientos tanto sobre las especificidades culturales del temperamento difícil como sobre el contenido del constructo temperamento en general. Estos resultados también pueden ayudar en el desarrollo de nuevas investigaciones sobre el temperamento difícil, así como en la planificación de intervenciones de salud mental y asesoramiento psicológico.(AU)

Difficult temperament is a set of behavioral characteristics that areassociated with mental health and a significant predictor of psychopathology.This study aims to investigate which temperamental characteristics can beconsidered attributes of difficult temperament in Lithuanian adults. The sampleconsisted of 429 adults between 18 and 79 years of age. The Adult TemperamentQuestionnaire was used to assess temperamental characteristics and perceiveddifficult temperament. Data were analyzed using a mixed-methods approach. Theresults revealed that the set of attributes perceived as constituting difficulttemperament includes characteristics such as negative mood, intensity ofemotional reactions, low adaptability, withdrawal, and low regularity.Quantitative data analysis uncovered an unexpected negative relationshipbetween perceived difficult temperament and the rhythmicity characteristic, whilea new category of stubbornness emerged in the qualitative data. The findingsprovide new knowledge about both the cultural specifics of difficult temperamentand the content of the temperament construct in general. These results can alsoaid in the development of further research on difficult temperament, as well as inthe planning of mental health interventions and psychological counseling.(AU)

Utilising online paradigms to explore the effect of boredom and sadness on children's snack choice: The role of parental feeding practices and child temperament.

Emotional eating (EE) is defined as eating in response to negative emotions (e.g., sadness and boredom). Child temperament and parental feeding practices are predictive of child EE and may interact to shape child EE. Previous research has demonstrated that children eat more when they are experiencing sadness, however, boredom-EE (despite how common boredom is in children) has yet to be explored experimentally using remote methodologies. The current study explores whether feeding practices and child temperament interact with mood to predict children's snack selection in an online hypothetical food choice task. Using online experimental methods, children aged 6-9-years (N = 347) were randomised to watch a mood-inducing video clip (control, sadness, or boredom). Children completed a hypothetical food choice task from images of four snacks in varying portion sizes. The kilocalories in children's online snack choices were measured. Parents reported their feeding practices and child's temperament. Results indicated that the online paradigm successfully induced feelings of boredom and sadness, but these induced feelings of boredom and sadness did not significantly shape children's online food selection. Parental reports of use of restriction for health reasons (F = 8.64, p = .004, n2 = 0.25) and children's negative emotionality (F = 6.81, p = .009, n2 = 0.020) were significantly related to greater total kilocalorie selection by children. Three-way ANCOVAs found no evidence of any three-way interactions between temperament, feeding practices, and mood in predicting children's online snack food selection. These findings suggest that children's hypothetical snack food selection may be shaped by non-responsive feeding practices and child temperament. This study's findings also highlight different methods that can be successfully used to stimulate emotional experiences in children by using novel online paradigms, and also discusses the challenges around using online methods to measure children's intended food choice.

The Effect of Temperament on Outcomes of Opioid and Non-Opioid Pediatric Dental Sedation.

Purpose: To assess oral sedation success using midazolam and hydroxyzine with and without meperidine, and to assess the relationship between child temperament and sedation outcomes. Methods: This study recruited children between the ages of 36 and 95 months who were randomly assigned to receive dental treatment with an oral sedation regimen of midazolam (0.5 mg/kg) and hydroxyzine (1.0 mg/kg) with or without meperidine (1.5 mg/kg). Data were collected from the treatment log and electronic health records. Parents completed the Child Behavior Questionnaire Short Form (CBQ-SF) to assess temperament. Results: The study included 37 participants. The overall treatment success rate was 54 percent. There were no significant differences in sedation outcome with age, sex, insurance status, sedation regimen, isolation method or duration of procedure. Children with high pre-operative Frankl behavioral ratings were more likely to have a successful sedation outcome (P <0.01). Children who displayed high soothability experienced higher rates of success (P =0.04), which was more pronounced in the non-opioid group (P <0.01). Conclusion: The study showed low rates of success for a relatively small sample size. There was no difference in sedation success between the opioid group and non-opioid group. However, pre-procedure behavior and temperament characteristic of sooth- ability may warrant more exploration as predictors of sedation success.

Behavioural and physiological responses to stressors in sheep with temperament classified by genotype or phenotype.

The single nucleotide polymorphism (SNP) rs107856856, located in the tryptophan hydroxylase-2 gene, is associated with the behavioural phenotype for sheep temperament measured at weaning. Here, we tested the association between that SNP and physiological and behavioural responses to stressors in adult sheep. Two groups of adult sheep, one with genotype A/A (calm genotype) and the other with G/G (nervous genotype) in rs107856856, were selected from 160 sheep and were exposed, twice, to an open-field arena and an isolation box test (IBT). During each repeat, the behaviour and physiological responses (cortisol, prolactin, dehydroepiandrosterone [DHEA], brain derived neurotrophic factor [BDNF], characteristics of the response of body temperature, and oxidative stress) were measured. The behavioural and physiological responses of the sheep were compared between genotypes and also between groups classified on their phenotype as assessed by their initial isolation box score ("low responders" and "high responders"). The SNP rs107856856 had some effects on the behavioural phenotype (IBT score) but no effects on the physiological response to stress (cortisol, prolactin, DHEA, BDNF, oxidative stress or changes in body temperature) in the adult sheep, probably because the sheep were exposed, and therefore had adapted, to human contact during their life.

Neural substrates of affective temperaments: An intersubject representational similarity analysis to resting-state functional magnetic resonance imaging in nonclinical subjects.

Previous research has suggested that certain types of the affective temperament, including depressive, cyclothymic, hyperthymic, irritable, and anxious, are subclinical manifestations and precursors of mental disorders. However, the neural mechanisms that underlie these temperaments are not fully understood. The aim of this study was to identify the brain regions associated with different affective temperaments. We collected the resting-state functional magnetic resonance imaging (fMRI) data from 211 healthy adults and evaluated their affective temperaments using the Temperament Evaluation of Memphis, Pisa, Paris and San Diego Autoquestionnaire. We used intersubject representational similarity analysis to identify brain regions associated with each affective temperament. Brain regions associated with each affective temperament were detected. These regions included the prefrontal cortex, anterior cingulate cortex (ACC), precuneus, amygdala, thalami, hippocampus, and visual areas. The ACC, lingual gyri, and precuneus showed similar activity across several affective temperaments. The similarity in related brain regions was high among the cyclothymic, irritable, and anxious temperaments, and low between hyperthymic and the other affective temperaments. These findings may advance our understanding of the neural mechanisms underlying affective temperaments and their potential relationship to mental disorders and may have potential implications for personalized treatment strategies for mood disorders.

The Global Temperament Project: Parent-reported temperament in infants, toddlers, and children from 59 nations.

Data from 83,423 parent reports of temperament (surgency, negative affectivity, and regulatory capacity) in infants, toddlers, and children from 341 samples gathered in 59 countries were used to investigate the relations among culture, gender, and temperament. Between-nation differences in temperament were larger than those obtained in similar studies of adult personality, and most pronounced for negative affectivity. Nation-level patterns of negative affectivity were consistent across infancy, toddlerhood, and childhood, and patterns of regulatory capacity were consistent between infancy and toddlerhood. Nations that previously reported high extraversion, high conscientiousness, and low neuroticism in adults were found to demonstrate high surgency in infants and children, and countries reporting low adult openness and high adult neuroticism reported high temperamental negative affectivity. Negative affectivity was high in Southern Asia, Western Asia, and South America and low in Northern and Western Europe. Countries in which children were rated as high in negative affectivity had cultural orientations reflecting collectivism, high power distance, and short-term orientation. Surgency was high in Southeastern and Southern Asia and Southern Europe and low in Eastern Asian countries characterized by philosophies of long-term orientation. Low personal income was associated with high negative affectivity. Gender differences in temperament were largely consistent in direction with prior studies, revealing higher regulatory capacity in females than males and higher surgency in males than females, with these differences becoming more pronounced at later ages. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Receptive and expressive vocabulary performance in 2- to 5-year-olds in care: The role of different care types and temperament.

The detrimental role of institutionalization in children's development has prompted the introduction of alternative care types designed to offer more personalized care. The current study aimed to test whether children in alternative care types (care villages, care homes, and foster care) performed better on vocabulary than those in institutions. The role of temperament, specifically perceptual sensitivity and frustration, and the interaction between temperament and care types on vocabulary performance were also explored. The study involved 285 2- to 5-year-old children from different care types, and they were assessed through receptive and expressive vocabulary tests and temperament scales. The results of the linear mixed model revealed that children in alternative care types exhibited significantly higher vocabulary scores compared with those in institutions. Moreover, perceptual sensitivity showed a positive association with receptive and expressive vocabulary skills and seemed to act as a protective factor by mitigating the lower vocabulary scores in institutions. Frustration moderated vocabulary outcomes differently for children in institutions and foster care, aligning with the diathesis-stress model and vantage sensitivity theory, respectively. The findings emphasize the positive role of alternative care types in vocabulary performance and the importance of children's temperamental traits in this process.

Validation of the shortened version of the Canine Behavioral Assessment and Research Questionnaire (C-BARQ) using participants from the Dog Aging Project.

The Canine Behavioral Assessment and Research Questionnaire (C-BARQ) is a 100-item owner-completed survey instrument used for assessing behavior and temperament of companion dogs. The shortened version of the C-BARQ (C-BARQ(S)) consists of 42 items of the long C-BARQ. We aimed to validate the shortened C-BARQ(S) by comparing it with the long questionnaire in the same human-dog pair. We examined data from a nationwide cohort of companion dogs enrolled in the large-scale longitudinal Dog Aging Project (DAP) study. Among 435 participating owners who completed both the long and shortened versions of the C-BARQ within 60 days of each other, agreement between individual questions of the long and shortened C-BARQ using an unweighted kappa statistic and percent agreement was examined. Associations between the two questionnaires for mean behavior and temperament domain scores and mean miscellaneous category scores were assessed using Pearson correlation coefficients. Of 435 dogs in the study, the mean (SD) age was 7.3 (4.3) years and 216 (50%) were female. Kappa values between the long and shortened C-BARQ for individual questions within the 14 behavior and temperament domains and a miscellaneous category ranged from fair to moderate (0.23 to 0.40 for 21 items and 0.41 to 0.58 for 26 items, respectively). Pearson correlation coefficients above 0.60 between both questionnaires for 12 of the 14 mean behavior and temperament domain scores and a category of miscellaneous items were observed. Kappa values for individual questions between the long and shortened C-BARQ ranged from fair to moderate and correlations between mean domain scores ranged from moderate to strong.

Early executive functioning predicts externalizing problems in neurodiverse preschoolers.

Children with autism spectrum disorder (ASD) often exhibit externalizing problems, which have been linked with increased anxiety and depression, peer rejection, and parental stress. Identification of early predictors of externalizing behaviors in autism will facilitate identification of vulnerable children and implementation of early preventative interventions. There is ample evidence that executive functioning, social functioning, and temperament are predictive of later externalizing problems in general populations, but less is known about these relations in ASD and other neurodiverse populations, particularly in the early preschool years. To address this gap, we assessed the relations between executive functioning, social functioning, and temperament at age 3 and externalizing problems at age 5 in a sample of neurodiverse children with ASD and other neurodevelopmental disorders and delays. Analyses revealed that severity of early executive functioning impairment predicted increased externalizing problems. Severity of social autism symptoms moderated this relationship such that the effect of executive functioning on externalizing problems decreased as autism symptoms increased. These findings suggest that executive functioning is an important target for identifying and developing interventions for vulnerable children and underscore the necessity of considering severity of autism symptoms when researching the development of externalizing problems in children with neurodevelopmental disorders.

How energy balance-related behaviours, temperament, stress and overweight associate: a cross-sectional study of Finnish preschoolers.

OBJECTIVE: This study aimed to (1) examine the clustering of energy balance-related behaviours (EBRB) and (2) investigate whether EBRB clusters, temperament and hair cortisol concentration (HCC) associate with overweight. DESIGN: We assessed food consumption using food records, screen time (ST) using sedentary behaviour diaries, sleep consistency and temperament (negative affectivity, surgency, effortful control) using questionnaires and HCC using hair samples. Accelerometers were used to assess physical activity (PA) intensities, sleep duration and sleep efficiency. Researchers measured each child's weight and height. We used finite mixture models to identify EBRB clusters and multilevel logistic regression models to examine the associations between EBRB clusters, temperament, HCC and overweight. SETTING: The cross-sectional DAGIS survey, data collected in 2015-2016. PARTICIPANTS: Finnish 3-6-year-olds (n 864) recruited through preschools. RESULTS: One-third of the participants were categorised into the cluster labelled 'Unhealthy diet, excessive screen time', characterised by unhealthy dietary choices (e.g. greater consumption of high-fat, high-sugar dairy products) and longer ST. Two-thirds were categorised into the second cluster, labelled 'Healthy diet, moderate screen time'. PA and sleep were irrelevant for clustering. Higher negative affectivity and lower effortful control associated with the 'Unhealthy diet, excessive screen time' cluster. EBRB clusters and HCC did not associate with overweight, but surgency was positively associated with overweight (OR = 1·63, 95 % CI 1·17, 2·25). CONCLUSIONS: Of the EBRB, food consumption and ST seem to associate. As temperament associates with EBRB clusters and overweight, tailored support acknowledging the child's temperament could be profitable in maintaining a healthy weight.

Exploring the Relationship Between Age at Nap Cessation and Social-Emotional Functioning in Children.

OBJECTIVE: The objective of this study was to examine variations in age at nap cessation and identify whether there is an association with social-emotional functioning (SEF) as measured by internalizing/externalizing behavior, child temperament, and social skills in a sample of early childhood education and care-attending children. METHODS: The sample comprised 1117 children from the Australian Effectiveness Early Educational Experiences for Children longitudinal early childhood study. We used children's age at nap cessation as retrospectively recalled by caregivers in 2011 or 2013 when children were between ages 2 and 7 years. Each child's SEF was reported by a caregiver using the Strengths and Difficulties Questionnaire, the Short Temperament Scale for Children, and the Social Skills Inventory Scale. Associations between children's age of nap cessation and SEF were tested using linear regressions. RESULTS: The children's age at nap cessation ranged from 6 months to 6 years. For each additional year of napping, children's total , conduct , externalizing , and peer behavior problems decreased by 0.39 (95% confidence interval [CI], -0.70 to -0.09), 0.11 (95% CI, -0.21 to -0.01), 0.11 (95% CI, -0.51 to -0.06), and 0.11 (95% CI, -0.20 to -0.02) units on the Strengths and Difficulties Questionnaire scale, respectively. No further significant associations were found. CONCLUSION: This is the first study reporting the age range of nap cessation and its associations with social-emotional functioning. Our findings demonstrate earlier cessation ages in Australian children attending Early Childhood Education and Care programs than previously reported and a small association with externalizing and peer problems.

Substance use disorders in adults with attention-deficit/hyperactivity disorder: The role of affective temperament.

OBJECTIVE: Substance Use Disorders (SUD) are common in adults with Attention-Deficit/Hyperactivity Disorder (ADHD). Although predictors of SUD in this population are relevant for prevention and treatment, they need further clarification. Affective temperaments potentially associated with SUD in adult ADHD patients were explored. METHODS: ADHD patients with and without SUD were compared for sociodemographic, clinical, and psychological characteristics through: Adult ADHD Self-Report Scale; Wender Utah Rating Scale; Temperament Evaluation Memphis for Pisa, Paris, and San Diego-Autoquestionnaire. Logistic regression investigated factors associated with SUD. RESULTS: We included one-hundred and thirty-six ADHD patients with (n = 51, 37.5 %) and without SUD (n = 85, 62.5 %). The presence of SUD was associated with irritable temperament (p = 0.009), as well as more frequent school failure (p = 0.038), legal problems (p = 0.039), and lifetime suicide attempts (p = 0.014). LIMITATIONS: The cross-sectional design, the relatively small sample size, and the use of self-administered questionnaires. CONCLUSIONS: This study confirms the greater overall severity of adult ADHD-SUD compared with ADHD-only patients and suggests the potential role of irritable temperament as a predictor of substance-related problems.

A preliminary investigation of epigenome-wide DNA methylation and temperament during infancy.

This study provides preliminary evidence for an epigenetic architecture of infant temperament. At 12 months of age, blood was collected and assayed for DNA methylation and maternally reported infant temperament was assessed using the Infant Behavior Questionnaire in 67 mother-infant dyads. Epigenome-wide analyses showed that the higher order temperament dimensions Surgency and Negative Affect were associated with DNA methylation. The epigenetic signatures of Surgency and Negative Affect were situated at genes involved in synaptic signaling and plasticity. Although replication is required, these results are consistent with a biologically based model of temperament, create new avenues for hypothesis-driven research into epigenetic pathways that underlie individual differences in temperament, and demonstrate that infant temperament has a widespread epigenetic signature in the methylome.

Rhesus infant nervous temperament predicts peri-adolescent central amygdala metabolism & behavioral inhibition measured by a machine-learning approach.

Anxiety disorders affect millions of people worldwide and impair health, happiness, and productivity on a massive scale. Developmental research points to a connection between early-life behavioral inhibition and the eventual development of these disorders. Our group has previously shown that measures of behavioral inhibition in young rhesus monkeys (Macaca mulatta) predict anxiety-like behavior later in life. In recent years, clinical and basic researchers have implicated the central extended amygdala (EAc)-a neuroanatomical concept that includes the central nucleus of the amygdala (Ce) and the bed nucleus of the stria terminalis (BST)-as a key neural substrate for the expression of anxious and inhibited behavior. An improved understanding of how early-life behavioral inhibition relates to an increased lifetime risk of anxiety disorders-and how this relationship is mediated by alterations in the EAc-could lead to improved treatments and preventive strategies. In this study, we explored the relationships between infant behavioral inhibition and peri-adolescent defensive behavior and brain metabolism in 18 female rhesus monkeys. We coupled a mildly threatening behavioral assay with concurrent multimodal neuroimaging, and related those findings to various measures of infant temperament. To score the behavioral assay, we developed and validated UC-Freeze, a semi-automated machine-learning (ML) tool that uses unsupervised clustering to quantify freezing. Consistent with previous work, we found that heightened Ce metabolism predicted elevated defensive behavior (i.e., more freezing) in the presence of an unfamiliar human intruder. Although we found no link between infant-inhibited temperament and peri-adolescent EAc metabolism or defensive behavior, we did identify infant nervous temperament as a significant predictor of peri-adolescent defensive behavior. Our findings suggest a connection between infant nervous temperament and the eventual development of anxiety and depressive disorders. Moreover, our approach highlights the potential for ML tools to augment existing behavioral neuroscience methods.

Analysis of nonsynonymous SNPs in candidate genes that influence bovine temperament and evaluation of their effect in Brahman cattle.

BACKGROUND: Temperament is an important production trait in cattle and multiple strategies had been developed to generate molecular markers to assist animal selection. As nonsynonymous single nucleotide polymorphisms are markers with the potential to affect gene functions, they could be useful to predict phenotypic effects. Genetic selection of less stress-responsive, temperamental animals is desirable from an economic and welfare point of view. METHODS AND RESULTS: Two nonsynonymous single nucleotide polymorphisms identified in HTR1B and SLC18A2 candidate genes for temperament were analyzed in silico to determine their effects on protein structure. Those nsSNPs allowing changes in proteins were selected for a temperament association analysis in a Brahman population. Transversion effects on protein structure were evaluated in silico for each amino acid change model, revealing structural changes in the proteins of the HTR1B and SLC18A2 genes. The selected nsSNPs were genotyped in a Brahman population (n = 138), and their genotypic effects on three temperament traits were analyzed: exit velocity, pen score, and temperament score. Only the SNP rs209984404-HTR1B (C/A) showed a significant association (P = 0.0144) with pen score. The heterozygous genotype showed a pen score value 1.17 points lower than that of the homozygous CC genotype. CONCLUSION: The results showed that in silico analysis could direct the selection of nsSNPs with the potential to change the protein. Non-synonymous single nucleotide polymorphisms causing structural changes and reduced protein stability were identified. Only rs209984404-HTR1B shows that the allele affecting protein stability was associated with the genotype linked to docility in cattle.

Identification of Candidate Genes and Pathways Linked to the Temperament Trait in Sheep.

Temperament can be defined as the emotional variability among animals of the same species in response to the same stimulus, grouping animals by their reactivity as nervous, intermediate, or calm. Our goal was to identify genomic regions with the temperament phenotype measured by the Isolation Box Test (IBT) by single-step genome-wide association studies (ssGWAS). The database consisted of 4317 animals with temperament records, and 1697 genotyped animals with 38,268 effective Single Nucleotide Polymorphism (SNP) after quality control. We identified three genomic regions that explained the greatest percentage of the genetic variance, resulting in 25 SNP associated with candidate genes on chromosomes 6, 10, and 21. A total of nine candidate genes are reported for the temperament trait, which is: PYGM, SYVN1, CAPN1, FADS1, SYT7, GRID2, GPRIN3, EEF1A1 and FRY, linked to the energetic activity of the organism, synaptic transmission, meat tenderness, and calcium associated activities. This is the first study to identify these genetic variants associated with temperament in sheep, which could be used as molecular markers in future behavioral research.