Heterogeneous trajectories of perceived stress and their associations with active leisure: a longitudinal study during the first year of COVID-19.

Introduction: There is a plethora of literature on the dynamics of mental health indicators throughout the COVID-19 pandemic, yet research is scarce on the potential heterogeneity in the development of perceived stress. Furthermore, there is a paucity of longitudinal research on whether active leisure engagement, which typically is beneficial in reducing stress, might have similar benefits during times of major disruption. Here we aimed to extend previous work by exploring the dynamics of change in stress and coping, and the associations with active leisure engagement over the first year of COVID-19. Methods: Data from 439 adults (Mage = 45, SD = 13) in Estonia who participated in a longitudinal online study were analyzed. The participants were assessed at three timepoints: April-May 2020; November-December 2020; and April-May 2021. Results: Mean stress and coping levels were stable over time. However, latent profile analysis identified four distinct trajectories of change in stress and coping, involving resilient, stressed, recovering, and deteriorating trends. Participants belonging to the positively developing stress trajectories reported higher active leisure engagement than those belonging to the negatively developing stress trajectories. Discussion: These findings highlight the importance of adopting person-centered approaches to understand the diverse experiences of stress, as well as suggest the promotion of active leisure as a potentially beneficial coping resource, in future crises.

Active vs passive novelty-related strategies: Sex differences in exploratory behaviour and monoaminergic systems.

Sex differences are apparent in numerous behavioural characteristics. In order to compare and characterise male and female variability of exploratory behaviour, 365 male and 401 female rats were assessed in a task where a bimodal response distribution had previously been established in males. Female rats had significantly higher exploratory activity, and presented normal distribution of the behaviour, very differently from the bimodal distribution of males. No major effect of litter or oestrous cycle was detected. Several differences between male and female rats were found in monoamine metabolism measured ex vivo. Male rats had lower levels of dopamine (DA) in frontal cortex, and higher levels of 3,4-dihydroxyphenylacetic acid (DOPAC) in raphe area; higher levels of serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) in dorsal striatum but lower levels of 5-HT and 5-HIAA in locus coeruleus area, 5-HIAA levels were also lower in hippocampus as compared to females. Males had higher noradrenaline (NA) levels in hippocampus and lower normetanephrine (NMN) levels in striatum, in both brain regions male animals had lower NMN/NA ratio. No sex difference was found in accumbens. The only brain region with an interaction between sex and the expression of exploratory activity was raphe: Here 5-HT levels were lower, and DOPAC levels and DOPAC/DA and 5-HIAA/5-HT ratios higher in low exploring male but not female rats. Conclusively, female rats not only display higher levels of exploration but the population distribution of this behaviour is distinct; this may be related to differences in the monoaminergic systems between female and male animals.

Studies in the Mentality of Literates: 3. Conceptual Structure and Nonsense of Personality Testing.

In this study, third in a series of studies of the relationships between the dominant type of the Word Meaning Structure (WMS) and various psychic processes, response patterns on personality questionnaires with Likert-type response format of individuals with different levels of education (including adult illiterates) in Brazil (N = 102) and in Estonia (N = 520) were assessed with person oriented methods of data analysis. We found that responses to two personality questionnaires (International Personality Item Pool Questionnaire, IPIP-Q60 and Estonian Collectivism Scale, ESTCOL) are inconsistent and do not correspond to theories that underlie construction and interpretation of such assessment tools. Two novel ways to assess inconsistent response patterns were developed. The Consistency Index (CI) characterizes between-item inconsistency and the Determinacy Index (DI) characterizes within-item inconsistency. The dominant type of the WMS and the level of education were related to both CI and DI. Higher level of between-item inconsistency characterizes everyday conceptual thinkers with lower levels of education and higher level of within-item inconsistency was observed among logical conceptual thinkers with higher levels of education. Systematic relationships between WMS and inconsistent patterns of responses indicate that responses on personality questionnaires cannot be interpreted in terms of personality characteristics. The results of our study also provide further support to the idea that dominant type of the WMS is a pervasive characteristic of the psyche and determines qualitatively possibilities and limits of the psychic processes. The results of this study are in agreement with the idea that WMS defines the "Great Divide."

Association of Impulsivity With Food, Nutrients, and Fitness in a Longitudinal Birth Cohort Study.

BACKGROUND: Impulsivity is a psychiatric vulnerability factor strongly associated with substance abuse but also with unhealthy diet. Whether these associations extend to specific nutrients is largely unknown. Therefore, we investigated the longitudinal association between diet, cardiorespiratory fitness, and 2 impulsivity dimensions in a representative sample of south Estonian adolescents and young adults. Impulsivity and dietary intake were measured 3 times in 2 birth cohorts at regular intervals in individuals aged 15 to 33 years. METHODS: The sample included 2 birth cohorts of the longitudinal Estonian Children Personality Behaviour and Health Study. The analytic sample size consisted of 2883 observations (56.4% females). The primary outcomes were adaptive and maladaptive impulsivity scores measured by an original 24-item Likert-type questionnaire. Impulsivity scores were predicted from the food diaries data converted into nutrient categories. A linear mixed-effects approach was used to model the time dependence between observations. RESULTS: Lower maladaptive impulsivity was associated with higher cardiorespiratory fitness (ß = -.07; 95% CI = -0.12; -0.03). Higher maladaptive impulsivity was associated with lower dietary intake of zinc (ß = -.10; -0.15; -0.06) and vegetables (ß = -.04; -0.07; -0.01) and higher intake of sodium (ß = .06; 0.02; 0.10). Vitamin B6 was positively associated with adaptive impulsivity (ß = .04; 0.01; 0.07). Additionally, some of the adjusted models showed significant but weak associations with selenium, alcohol, fish, and cereal products. CONCLUSIONS: Food choice may affect the neurochemistry and therefore regulate the manifestations of impulsivity. We identified associations between several (micro)nutrients and maladaptive impulsivity.

Association of orexin/hypocretin receptor gene (HCRTR1) with reward sensitivity, and interaction with gender.

Orexins/hypocretins maintain wakefulness, increase appetite and participate in the coordination of stress response. We have recently provided evidence on the role of orexins in aggression, showing the association of the HCRTR1 genotype. (rs2271933 G > A; leading to amino acid substitution Ile408Val) with aggressiveness or breach of law in four independent cohorts. Aggressive behaviour can be reward driven and hence we have examined the association of HCRTR1 rs2271933 genotype with different aspects of reward sensitivity in the birth cohort representative Estonian Children Personality Behaviour and Health Study. HCRTR1 genotype was associated with reward sensitivity in a gender dependent manner. Male HCRTR1 A/A homozygotes had higher Openness to Rewards and the overall reward sensitivity score while, in contrast, female A/A homozygotes scored lower than G-allele carriers in Openness to Rewards. In the total sample, aggressiveness correlated positively with reward sensitivity, but this was on account of Insatiability by Reward. In contrast, the HCRTR1 A/A homozygotes had a positive association of aggressiveness and Openness to Rewards. Experience of stressful life events had a small but significant increasing effect on both aspects of reward sensitivity, and correlated in an anomalous way with reward sensitivity in the HCRTR1 A/A homozygotes. Conclusively, the higher aggressiveness of HCRTR1 A/A homozygotes appears based on a qualitative difference in sensitivity to rewards, in the form that suggests their lower ability to prevent responses to challenges being converted into overt aggression.

The role of reward sensitivity in obesity and its association with Transcription Factor AP-2B: A longitudinal birth cohort study.

OBJECTIVE: One factor potentially contributing to obesity is reward sensitivity. We investigated the association between reward sensitivity and measures of obesity from 9-33 years of age, paying attention to the inner structure of reward sensitivity. METHODS: The sample included both birth cohorts (originally n = 1176) of the Estonian Children Personality Behaviour and Health Study. The association between reward sensitivity and measures of obesity was assessed using mixed-effects regression models. Associations at ages 9 (younger cohort only), 15, 18, 25 and 33 (older cohort) years were analyzed by one-way ANOVA. The indirect effect of the gene encoding transcription factor 2 beta (TFAP2B) on obesity through reward sensitivity was tested using mediation analysis. RESULTS: According to linear mixed effects regression models, an increase in scores of Insatiability by Reward and both of its components, Excessive Spending and Giving in to Cravings, significantly increased body weight, body mass index, sum of five skinfolds, waist circumference, hip circumference and waist-to-height ratio from 15 to 25 years of age. Findings were similar at age 9 and 33 years. In contrast, no association between obesity and Openness to Rewards or its facets was observed. The TFAP2B genotype was also associated with fixation to rewards in females, but not with striving towards reward multiplicity. CONCLUSION: Our results suggest that reward sensitivity is associated with obesity by its reward fixation component. The heterogeneity of the reward sensitivity construct should be taken into account in studies on body composition.

Reward sensitivity, affective neuroscience personality, symptoms of attention-deficit/hyperactivity disorder, and TPH2-703G/T (rs4570625) genotype.

OBJECTIVE: Reward sensitivity is an increasingly used construct in psychiatry, yet its possible inner structure and relationship with other affective variables are not well known. METHODS: A reward sensitivity measurement scale was constructed on the basis of large item pool collected from birth cohort representative samples (the Estonian Children Personality Behaviour and Health Study; original n = 1238). Affective Neuroscience Personality Scale (ANPS) and the Adult Attention deficit hyperactivity disorder (ADHD) Self-Report Scale (ASRS) were administered in young adulthood. A variant (rs4570625) of the gene encoding tryptophan hydroxylase 2 (TPH2) that is responsible for the synthesis of central serotonin was genotyped. RESULTS: Reward sensitivity consisted of two orthogonal components, operationally defined as Openness to Rewards and Insatiability by Reward, that respectively characterise the striving towards multiple rewards and the strong pursuit and fixation to a particular reward. While SEEKING and PLAY (and to lower extent CARE) of the ANPS co-varied with Openness to Rewards, FEAR, SADNESS, and ANGER were related to Insatiability by Reward. The total score of ASRS was moderately correlated with Insatiability by Reward, while the association with Openness to Rewards was negligible. However, ASRS Inattention had some negative relationship with the Social Experience facet of Openness to Rewards. The T/T homozygotes for the TPH2 promoter polymorphism had lower Insatiability by Reward but not Openness to Rewards. CONCLUSIONS: Behaviours sensitive to rewards are separable to the components of variability and fixation, and these components are differentially related to affective aspects of personality, attention, and hyperactivity as well as to TPH2 genotype.

Adaptive and maladaptive impulsivity, platelet monoamine oxidase (MAO) activity and risk-admitting in different types of risky drivers.

RATIONALE: Platelet monoamine oxidase (MAO) activity reflects serotonergic functioning associated with impulsive behaviour, but the significance of these associations to real-life impulsive behaviour in healthy subjects is not clear. OBJECTIVES: The present study explores impulsivity and platelet MAO activity among people with driving violations. MATERIALS AND METHODS: We compared facets of impulsivity and platelet MAO activity in 1,004 male drivers, out of whom 203 had been caught by the police driving drunk and 292 had been caught exceeding speed limits and committing other non-alcohol-related driving violations. Subjects with speeding and other non-alcohol-related violations were further divided according to their self-reported risk-admitting of exceeding speed limits. RESULTS: While drunk driving was associated only with maladaptive types of impulsivity, exceeding speed limits was associated with functional impulsivity and excitement seeking and, to a lesser degree, with dysfunctional impulsivity. Drunk drivers had lower platelet MAO activity. Risk-admitting high-risk drivers had higher platelet MAO activity, neuroticism-related impulsivity, dysfunctional impulsivity and excitement seeking compared to all other groups and higher functional impulsivity compared to controls. Risk-denying high-risk drivers had only higher functional impulsivity compared to controls. CONCLUSIONS: This study demonstrates different expressions of functional and dysfunctional impulsivity in behaviour. While platelet MAO activity is lower in alcohol-related risky behaviour, non-alcohol-related self-acknowledged risky behaviour is related to higher platelet MAO activity. Thus, deviance towards lower as well as higher end of central serotonergic functioning may lead to impulsive behaviour. While self-reported impulsivity did not correlate with MAO activity, both MAO activity and impulsivity were related to risky behaviour.

Possible interpretation of subjective complaints in patients with spontaneous subarachnoid haemorrhage.

OBJECTIVE: To analyse factors related to subjective non-cognitive and cognitive complaints in patients with spontaneous subarachnoid haemorrhage. SUBJECTS: Twenty-seven patients with subarachnoid haemorrhage and 27 age-, sex- and education-matched healthy controls. METHODS: A battery of cognitive tests measuring visuo-spatial abilities, verbal abilities, and fine-motor skill, Brief Social Support Questionnaire, and Life Orientation Scale were individually presented to all participants. RESULTS: Cognitive complaints were related to low social support but not to cognitive performance. Complaints about headaches and dizziness were also related to decreased cognitive performance. Above-normal optimistic life-orientation was related to the absence of complaints in patients with subarachnoid haemorrhage. Healthy participants were best discriminated from patients with subarachnoid haemorrhage by less satisfactory social support system and decreased fine motor skills in the latter group. CONCLUSION: Change in social support network may be an important resource for increasing quality of life in patients with subarachnoid haemorrhage not only through help provided by supporters but also indirectly, through increasing subjective well-being. The absence of subjective complaints in patients with subarachnoid haemorrhage is not necessarily related to better objective condition but rather to inadequately optimistic life orientation.

Low platelet MAO activity associated with high dysfunctional impulsivity and antisocial behavior: evidence from drunk drivers.

RATIONALE: Low platelet monoamine oxidase (MAO) activity is associated with problem drinking and other deviant behaviors. Since the majority of alcohol abusers are smokers, and tobacco smoke has a direct inhibitory effect on the enzyme, these associations may not be meaningful. OBJECTIVE: The authors compared platelet MAO activity and impulsivity in police-referred subjects caught driving while intoxicated and in control subjects, controlling for smoking. METHODS: Platelet MAO activity was measured radioenzymatically and impulsivity scores obtained from questionnaires. Smoking status was self-reported. RESULTS: Subjects caught driving while intoxicated had significantly higher dysfunctional impulsivity and lower platelet MAO activity than control subjects. This difference in platelet MAO activity between the two groups was significant in non-smokers and ex-smokers. CONCLUSIONS: These findings demonstrate that platelet MAO activity is lower in subjects with socially deviant behavior, and the association of low platelet MAO and problem drinking is not an artifact of smoking.