Staying connected in old age: associations between bonding social capital, loneliness and well-being and the value of digital media.

OBJECTIVES: We examined associations between age, bonding social capital (BSC), loneliness and psychological, social and emotional well-being in old age. As in theory digital media can support both preservation of and access to someone's social capital, we also explored associations between the use of WhatsApp, social network sites (SNS) and Internet applications and respectively BSC and loneliness. METHOD: In this cross-sectional study a sample of 349 older adults (range = 70y-93y; Mean(SD)=74.8y(4.9y); 59.6% male) filled out a questionnaire including the bonding social capital subscale of the personal social capital scale for elderly (PSCSE), validated scales measuring social, emotional, and psychological well-being and loneliness, the SNS intensity scale and items measuring frequencies of Whatsapp use and use of various Internet functions. Also relevant demographic and other covariates were included. RESULTS: Regression analyses including relevant covariates confirmed our hypotheses, finding negative associations between BSC and both age and loneliness, and positive associations between BSC and psychological, social and emotional well-being. WhatsApp and Internet use were both found positively associated with BSC, whilst a negative association between WhatsApp use and loneliness was found. SNS use was not associated with BSC nor with loneliness. CONCLUSION: Our findings indicate BSC as an important factor in positive aging and illustrate a widening gap between the need for socio-emotional resources versus their availability. With regard to digital media, we conclude that its value in old age should be sought in providing access to one's bonding social capital rather than adding to it by expanding the number of social relations.

Bonding personal social capital as an ingredient for positive aging and mental well-being. A study among a sample of Dutch elderly.

OBJECTIVES: The current study aims to add to the limited empirical research of possible benefits of personal social capital for the well-being of elderly. A validated personal social capital scale, measuring both bonding and bridging social capital in a general population, was adjusted to fit the characteristics of the social environment of elderly, to explore the association between social capital and well-being of elderly, as well as the mediating role of loneliness. METHOD: A sample of 328 Dutch adults, varying in age from 65 to 90 years (Mean = 72.07; SD = 4.90) filled out an online questionnaire including the adapted personal social capital scale for elderly (PSCSE), as well as validated scales measuring social, emotional, and psychological well-being and loneliness. Relevant other (demographic) variables were included for testing construct and criterion validity. RESULTS: CFA analysis revealed the subdimensions bonding and bridging social capital with reliability scores of respectively α = .88 and α = .87, and α = .89 for the total scale. Regression analyses confirmed construct and criterion validity. Subsequently, significant positive associations between bonding social capital and respectively social, emotional and psychological well-being were found. These associations were mediated by loneliness. Bridging social capital was only found to be significantly associated with social well-being, not mediated by loneliness. CONCLUSION: Our findings have enhanced our understanding of the association between social capital and mental well-being of elderly and indicate that bonding personal social capital in particular may be considered an ingredient for positive aging.

Gratitude and loneliness in adults over 40 years: examining the role of psychological flexibility and engaged living.

OBJECTIVES: The aim of the present study was to investigate the association between trait gratitude and loneliness in a Dutch population sample of adults over 40 years. In addition, the mediating role of psychological flexibility and engaged living between trait gratitude and loneliness was assessed. METHOD: A total sample of 163 adults of which 65 men (40%) and 98 women (60%) between 41 and 92 years (Mage = 66, SDage = 12) participated in this study. Data from the Loneliness Questionnaire, Flexibility Index Test, Engaged Living Scale and the Short Gratitude, Resentment, and Appreciation Test were used. Mediation analysis was performed. RESULTS: Analysis showed a negative association between trait gratitude and loneliness. In addition, after adjusting for the demographic variables age, gender and educational level, the association between trait gratitude and loneliness was fully mediated by psychological flexibility, and partially mediated by engaged living. CONCLUSION: This study endorses the importance of trait gratitude and psychological flexibility in relation to experiencing loneliness. Further research is needed to replicate these findings in a more diverse sample and to investigate the causal relationships between these constructs. It would also be interesting to further investigate the role of different age groups and goal (dis)engagement strategies in this relation.

Cultural differences in positive psychotic experiences assessed with the Community Assessment of Psychic Experiences-42 (CAPE-42): a comparison of student populations in the Netherlands, Nigeria and Norway.

BACKGROUND: Previous studies have suggested that culture impacts the experience of psychosis. The current study set out to extend these findings by examining cultural variation in subclinical positive psychotic experiences in students from The Netherlands, Nigeria, and Norway. Positive psychotic experiences were hypothesized to (i) be more frequently endorsed by, and (ii) cause less distress in Nigerian vs. Dutch and Norwegian students. METHODS: Psychology students, aged 18 to 30 years, from universities in the Netherlands (n = 245), Nigeria (n = 478), and Norway (n = 162) were assessed cross-sectionally with regard to the frequency of subclinical positive psychotic experiences and related distress, using the Community Assessment of Psychic Experiences (CAPE-42). Multi-group confirmatory factor analysis and multivariate analysis of covariance were performed to assess measurement invariance of the positive symptom dimension (CAPE-Pos) and compare mean frequency and associated distress of positive psychotic experiences across study samples. RESULTS: Only CAPE-Pos items pertaining to the dimensions 'strange experiences' and 'paranoia' met assumptions for (partial) measurement invariance. Frequencies of these experiences were higher in the Nigerian sample, compared to both the Dutch and Norwegian samples, which were similar. In addition, levels of experience-related distress were similar or higher in the Nigerian sample compared to respectively the Dutch and Norwegian samples. CONCLUSION: Although positive psychotic experiences may be more commonly endorsed in non-Western societies, our findings do not support the notion that they represent a more benign, and hence less distressing aspect of human experience. Rather, the experience of psychotic phenomena may be just as, if not more, distressing in African than in European culture. However, observed differences in CAPE-Pos frequency and distress between samples from different cultural settings may partly reflect differences in the measure rather than in the latent trait. Future studies may therefore consider further cross-cultural adaptation of CAPE-42, in addition to explicitly examining cultural acceptance of psychotic phenomena, and environmental and other known risk factors for psychosis, when comparing and interpreting subclinical psychotic phenomena across cultural groups.

Measuring Gratitude: A Comparative Validation of the Dutch Gratitude Questionnaire (GQ6) and Short Gratitude, Resentment, and Appreciation Test (SGRAT).

The aim of this article was to validate and compare the Dutch translations of the Gratitude Questionnaire (GQ6) and the Short Gratitude, Resentment, and Appreciation Test (SGRAT) in an adult general population sample. In an online survey, 706 respondents (M age = 44, SD age = 14) completed Dutch versions of the GQ6, the SGRAT, the Satisfaction With Life Scale (SWLS) and the Positive Affect and Negative Affect Schedule (PANAS). At six week follow-up, 440 (62%) of them (M age = 46, SD age = 14) again completed the GQ6-NL and SGRAT-NL. Parallel analyses, exploratory factor analyses and confirmatory factor analyses revealed and confirmed one factor for the GQ6-NL, and three factors for the SGRAT-NL. Internal consistency indices of the GQ6-NL and of the SGRAT-NL were satisfactory. Both questionnaires demonstrated good test-retest reliability. Regression analyses showed, for the total scores on both gratitude questionnaires, positive associations with the SWLS and the Positive Affect Scale, and negative associations with the Negative Affect Scale. The results support the validity of the Dutch GQ6 and SGRAT. These questionnaires can be used to conduct further research of the grateful disposition in Dutch speaking individuals and groups.

Beyond Difference Scores: Unlocking Insights with Polynomial Regression in Studies on the Effects of Implicit-Explicit Congruency.

The aim of our study was to investigate whether theories of congruence are better tested using polynomial regression analysis, rather than expressing discrepancy between implicit and explicit measures as continuous or categorical difference scores. This paper also aims to make knowledge more accessible by providing a step-by-step explanation of both methods, illustrating differences between them, and making materials openly available for other researchers. In this paper, implicit and explicit measures of self-esteem are used as predictors for depressive symptoms, anxiety, and aggression in a general population sample (N = 135). Explicit self-esteem was measured using the Rosenberg Self-Esteem Scale, implicit self-esteem was measured using the Implicit Association Test, and the Symptom Questionnaire was used to measure depressive symptoms, anxiety, and aggression. The results show those difference score models all imply that the discrepancy between implicit and explicit self-esteem explains depression and anxiety, but not aggression. However, polynomial regression analysis shows that depression and anxiety are not accounted for by the explicit-implicit discrepancy as such, but are foremost explained by explicit self-esteem. Polynomial regression has the potential to evaluate more complex and more detailed hypotheses than what would be possible using statistical approaches based on discrepancy scores. It is therefore recommended for future research aimed at disentangling the roles of explicit and implicit self-esteem in psychological outcomes.

Prospective associations between working alliance, basic psychological need satisfaction, and coaching outcome indicators: a two-wave survey study among 181 Dutch coaching clients.

BACKGROUND: The coach-coachee working alliance and coachee motivation seem important factors for achieving positive coaching results. Self-determination theory, specifically basic psychological need theory, has been proposed as a relevant framework for understanding these relationships. The current longitudinal survey study therefore investigates prospective associations between coachees' appraisal of the working alliance, basic psychological need satisfaction, and the coaching outcome indicators goal attainment, wellbeing, absence of psychopathology, and personal growth initiative. METHODS: The sample (N = 181) consisted of Dutch coachees that were recruited across a range of coaching settings and contexts. Online self-report questionnaires were administered twice (T0 and T1), with an intervening time of 3 weeks, assessing working alliance, basic psychological need satisfaction, goal attainment, wellbeing, absence of psychopathology, and personal growth initiative. Parallel analysis with Monte Carlo simulations and confirmatory factor analyses were performed to assess the dimensionality of working alliance and basic psychological need satisfaction scores. Multiple regression analyses (stepwise) were used to examine prospective (T0 to T1) associations between working alliance and basic psychological need satisfaction, and their association with outcome indicators. RESULTS: The coachees' perception of the working alliance was positively and reciprocally, although modestly, associated with basic psychological need satisfaction. In addition, both working alliance and basic psychological need satisfaction were prospectively associated with goal attainment, but not with other outcome indicators. CONCLUSIONS: Results provide tentative support for a role of basic psychological need satisfaction in facilitating the establishment of a good working alliance. Additionally, the perception of a good quality, need supportive relationship with the coach appears to be associated with better goal achievement, but not with other outcome indicators. Associations were generally modest, and more research is needed to better measure and comprehend the unique contributions of specific relational and motivational factors to outcomes in coaching and assess the robustness of the current study findings.

Longitudinal measurement invariance of the Working Alliance Inventory - Short form across coaching sessions.

BACKGROUND: Throughout the psychotherapeutic and coaching literature, the client-therapist or coach-coachee working alliance has been highlighted as key force driving positive outcome. The Working Alliance Inventory Short form (WAI-S) for coaching charts the quality of working alliance throughout coaching sessions and is broadly applied in coaching research. Due to a shortfall in research on psychometric properties of the WAI-S, the purpose of this study was to examine (a) if the theorized three-factor structure of the 12-item WAI-S forms a solid representation of the dimensions of working alliance in coaching, and (b) longitudinal measurement invariance (LMI) of the WAI-S. METHOD: Data were collected in a two-wave study design comprising a main study sample of N = 690 Dutch coachees that completed the questionnaire at the first measurement, of which N = 490 also completed the questionnaire at the second measurement. Post hoc sensitivity analysis was performed based on the original sample, lacking additional information on covariates, and included both completers and dropouts, comprising N = 1986 respondents at T1, and N = 1020 respondents at T2. RESULTS: Confirmatory factor analyses evidenced best fit of the three-factor model in comparison to one-, and two-factor models at both time points. Despite the fact that multigroup confirmatory factor analysis detected non-invariant intercepts, our findings overall supported measurement invariance across coaching sessions. CONCLUSIONS: As decisions in both clinical and scientific practices generally rely on outcome assessment of interpersonal change in scores on the same measure over time, we believe our findings to be of contributing value to the consolidation of interpretation and accuracy of scorings on the WAI-S in coaching.

Psychosocial stress is associated with in vivo dopamine release in human ventromedial prefrontal cortex: a positron emission tomography study using [¹8F]fallypride.

Rodent studies suggest that prefrontal dopamine neurotransmission plays an important role in the neural processing of psychosocial stress. Human studies investigating stress-induced changes in dopamine levels, however, have focused solely on striatal dopamine transmission. The aim of this study was to investigate in vivo dopamine release in the human prefrontal cortex in response to a psychosocial stress challenge, using the highly selective dopamine D2/3 PET radioligand [¹8F]fallypride in healthy subjects. Twelve healthy subjects (age (y): 39.8; SD=15.8) underwent a single dynamic Positron Emission Tomography (PET) scanning session after intravenous administration of 185.2 (SD=10.2) MBq [¹8F]fallypride. Psychosocial stress was initiated at 100 min postinjection. PET data were analyzed using the linearized simplified reference region model (LSRRM), which accounts for time-dependent changes in [¹8F]fallypride displacement. Voxel-based statistical maps, representing specific D2/3 binding changes, were computed to localize areas with increased ligand displacement after task initiation, reflecting dopamine release. The psychosocial stress challenge induced detectable amounts of dopamine release throughout the prefrontal cortex, with dopaminergic activity in bilateral ventromedial prefrontal cortex being associated with subjectively rated experiences of psychosocial stress. The novel finding that a mild psychosocial stress in humans induces increased levels of endogenous dopamine in the PFC indicates that the dynamics of the dopamine-related stress response cannot be interpreted by focusing on mesolimbic brain regions alone.

Optimism and Mental Health in Adolescence: a Prospective Validation Study of the Dutch Life-Orientation Test-Revised (LOT-R-A) for Adolescents.

The study aimed to examine the psychometric properties of the Dutch Life Orientation Test-Revised for Adolescents (LOT-R-A), a self-report questionnaire assessing dispositional optimism, and to evaluate the two-factor structure (optimism, pessimism). The LOT-R-A and the questionnaires measuring well-being (MHC-SF-A) and psychological problems (SDQ) were completed by 459 Dutch adolescents (178 boys and 281 girls) between the ages of 11 and 18 years at baseline and 281 adolescents at a four-week follow-up. The results confirmed the two-factor structure (optimism, pessimism) of the LOT-R-A. The findings provided evidence of internal consistency of scores ranging from low to good, and evidence of good test-retest reliability of scores. Further, scores of optimism were cross-sectionally positively associated with scores of positive emotions and well-being and negatively with scores of psychological problems and negative emotions, providing evidence of convergent and divergent validity of optimism scores with emotions, well-being, and psychological problems. Lastly, scores of optimism were prospectively positively associated with scores of well-being and negatively with scores of psychological problems, providing evidence of criterion validity of optimism scores with well-being and psychological problems. Based on these findings it can be concluded that the LOT-R-A is a valid instrument to examine optimism among adolescents. Future research can help to elucidate the role of optimism in mental health interventions and can gather knowledge on how these interventions can be refined to optimally cultivate optimism during the developmental period of adolescence.

Psychometric Properties of Two Implicit Associations Tests measuring Adult Attachment.

Adult attachment style has consequences for mental health, interpersonal functioning and emotion regulation. This occurs partly deliberately, also referred to as explicit, and partly on an automatic level outside of conscious awareness, also referred to as implicit. Whereas explicit adult attachment can be assessed with self-report instruments, measurement of implicit adult attachment requires indirect methods. This paper describes the psychometric properties of two Implicit Association Tests measuring general adult attachment in a population sample. The study evaluated the reliability and the validity of the Avoidant Attachment IAT (ANX-IAT) and the Anxious Attachment IAT (AVOID-IAT). Validity was evaluated against self-report measures of adult attachment style (RQ), psychopathology (SQ-48), and well-being (MHC-SF). The split-half reliabilities of both IATs were good; the test-retest reliability of the ANX-IAT was adequate; however the AVOID-IAT had low test-retest reliability. Both IATs did not explain variance in psychopathology additional to explicit measures. The AVOID-IAT showed added value over explicit measurement of avoidant attachment in explaining variance in well-being, particularly regarding emotional and psychological well-being. The ANX-IAT did not explain variance in any measure of well-being additional to the explicit measure of anxious attachment. Our findings provide a basis from which more valid IATs measuring general adult attachment can be developed. Furthermore, they suggest that implicit avoidant attachment might be related to well-being, particularly emotional and psychological well-being. However, further research is needed to investigate the role of implicit general adult attachment in mental health and to optimize the two IATs in terms of validity before clinical use is recommended.

Companion Animals as Buffer against the Impact of Stress on Affect: An Experience Sampling Study.

Companion animals have been identified as a unique source of social support and as contributors to mental wellbeing. This study uses the Experience Sampling Method to test whether this effect is due to stress-buffering. A total of 159 dog and cat owners responded to a series of randomly scheduled questionnaires on their smartphones. At each measurement moment, they reported in whether a pet is present at that moment and to what extent they have interacted with the pet. They also reported on stressful activities and events and on their current positive (PA) and negative (NA) affect. Multilevel regression analyses showed that when a companion animal was present (vs. absent) the negative association between stress and PA is less pronounced (event stress: B = 0.13, p = 0.002, 95% CI = 0.05; 0.21 activity stress: B = 0.08, p < 0.001, 95% CI = 0.04; 0.12). No additional main effect was revealed when tested in a subsample of records that reported low or no stress. Main effects were found for the presence of a companion animal on negative affect (B = 0.08, p < 0.001; 95% CI = 0.12; 0.05) and for interacting with a companion animal on positive affect (B = 0.06, p < 0.001; 95% CI = 0.04; 0.08). This shows that the presence of a companion animal buffers against the negative consequences of stress on positive affect, indicating stress-buffering as a mechanism behind the pet-effect. It is, however, not the only mechanism and more research is required to further elucidate how companion animals contribute to human wellbeing.

Individual and situational determinants of plastic waste sorting: an experience sampling method study protocol.

BACKGROUND: Plastic waste management is one of the most challenging problems of our time. Until now, only 9% of the produced plastics has been recycled. In order to increase recycling, a behavior change towards sorting of plastic waste is needed. Therefore, the main aim of the study is to gain insight in the individual and situational determinants associated with plastic waste sorting behavior. The Integrated Framework for Encouraging Pro-environmental Behaviour will be used as the theoretical framework. This framework assumes that individual egoistic and hedonic values are negatively related to pro-environmental behaviour, whereas individual biospheric and altruistic values are positively related to pro-environmental behaviour. Situational cues can activate these values, resulting in (non) pro-environmental behaviour. Taking the Integrated Framework for Encouraging Pro-environmental Behaviour into account, this study will test the hypothesized associations between individual and situational determinants and plastic waste sorting behavior, using an ecological momentary assessment approach (Experience Sampling Method, ESM). METHODS: A signal-contingent scheme with semi-random intervals will be used for the ESM questionnaire. Over a period of seven consecutive days, an ESM-based smartphone app will prompt participants ten times a day to fill in a short questionnaire containing questions about situational determinants and plastic waste sorting behaviour. Participants will also complete an online questionnaire before and after the study measuring the individual determinants and plastic waste sorting behaviour. DISCUSSION: ESM has many benefits over traditional surveys, such as improved ecological validity and the possibility to explore temporal relationships. The disadvantages of ESM are mainly related to the burden for the participants and the possibility of reactivity effects. The results will provide insight into the relationship between situational cues, individual values and plastic waste behaviour. The practical implications of the findings of this study can be of interest for policy makers in order to reach plastic waste reduction targets. Furthermore, the situational cues that activate values, which increase or decrease plastic waste sorting, can be targeted in interventions. The results of this study can also be relevant for further research studying and stimulating pro-environmental behaviour in general.

Recovery from daily-life stressors in early and chronic psychosis.

Initial affective and psychotic reactivity to daily stressors is altered in psychosis, and most notably in early psychosis. In addition to altered initial stress reactivity, results from studies using Experience Sampling Methodology (ESM) and psychophysiological measures indicate that impaired recovery from mild stressors may also be a risk factor for mental illness. The current ESM study investigated affective recovery from daily stressors in chronic psychosis patients (CP; n = 162), individuals at early stages of psychosis (EP; n = 127), and healthy volunteers (HV; n = 220) assessing fluctuations in negative affect (NA), tension, and suspiciousness ten times a day on six consecutive days. Recovery was operationalized for all three variables as the return to baseline (i.e., level at t-1) following the first stressful event of a day (i.e., t0). The EP group showed a delayed recovery of NA (t1-t3: B = 0.185; p = .007 and B = 0.228; p = .002) and suspiciousness (t1: B = 0.223; p = .010 and B = 0.291; p = .002) compared to HV and CP, respectively. Delayed recovery was detected for tension as well (t1-t2: EP > HV: B = 0.242; p = .040 and EP > CP: B = 0.284; p = .023), but contrary to both other momentary states, this effect disappeared when controlling for subsequent stressful events. There were no significant differences in recovery between HV and CP. These results suggest that in EP, stressful daily events have longer-lasting effects on overall negative affect and subclinical psychotic-like experiences. Future studies should incorporate physiological and endocrine measures in order to integrate recovery patterns of the different stress systems.

Overall cortisol, diurnal slope, and stress reactivity in psychosis: An experience sampling approach.

OBJECTIVE: Results from experimental studies suggest that psychosis and psychosis liability are associated with increased cortisol levels and blunted cortisol reactivity, and that use of antipsychotics may reduce these aberrations. Here, we report on overall cortisol, diurnal slope, and cortisol stress reactivity in everyday life in psychosis and psychosis liability using the experience sampling method (ESM). METHODS: Our sample consisted of individuals diagnosed with psychotic disorder currently on (MPD; n = 53) or off antipsychotic medication (NMPD; n = 20), first-degree relatives of psychotic patients (REL; n = 47), and healthy volunteers (HV; n = 67). Saliva samples were collected throughout the day on six consecutive days and analyzed for cortisol levels. Simultaneously, stressfulness of the current activity was assessed with ESM questionnaires. RESULTS: We found no group differences in overall cortisol level between groups, but REL had a steeper diurnal slope than HV; in MPD a trend was found in the same direction. Regarding reactivity to stressful activities, results indicated attenuation of the cortisol response in both patient groups compared to HV. CONCLUSION: These results do not confirm reports of increased cortisol levels in psychosis, but provide evidence of stress-related cortisol alterations in everyday life.

Psychotic reactivity to daily life stress and the dopamine system: a study combining experience sampling and [18F]fallypride positron emission tomography.

Stressful life events increase the risk for psychosis, and the subjective experience of stress related to daily life activities drives moment-to-moment variation in psychotic intensity. Positron emission tomography (PET) studies suggest that dopaminergic (DAergic) activity mediates the behavioral response to an experimental stressor. However, it is not known how alterations in this DAergic stress response relate to the subjective experience of stress in real life situations assessed in momentary assessment studies. This study combined [18F]fallypride PET with an Experience Sampling ambulatory assessment approach to examine the association between the prefrontal DAergic response to experimentally induced stress and real life psychotic reactivity to the subjective experience of stress in daily life. Healthy first-degree relatives of individuals with a psychotic disorder (N = 14) and healthy controls (N = 11) participated in (a) a psychosocial [18F]fallypride PET stress paradigm and (b) an experience sampling study, using a structured diary approach. Mixed multilevel random intercept models revealed that stress-induced [18F]fallypride displacement, indicative of DAergic activity, in ventromedial prefrontal cortex (VMPFC) was associated with psychotic reactivity to daily life stress in the entire sample. Lower levels of [18F]fallypride displacement to stress predicted increased psychotic reactivity to daily life stress. This study combined PET neuroimaging with real life behavioral assessments in the investigation of psychotic symptoms; we showed decreased [18F]fallypride displacement to stress in VMPFC to be associated with increased psychotic reactivity to daily life stress. The preliminary evidence in this study demonstrates that it is possible to acquire a grasp on how brain function is associated with contextualized experience, which has relevance for neuroimaging studies in general.

Resilience to affective disorders: a comparative validation of two resilience scales.

BACKGROUND: Resilience to affective disorders in rehabilitating patients or in individuals with a severe disability is of special research interest. However, there is no gold standard for measuring resilience. We aimed to test the accuracy of the Dutch translation of the Brief Resilience Scale (BRSnl) and of the Resilience Scale (RSnl) in recognizing rehabilitating patients without anxiety and depression, and to determine the reliability and construct validity of both scales. METHODS: A within-subjects longitudinal study with six assessments, each one week apart. Forty residents of a nursing home rehabilitating unit were interviewed to assess resilience (BRSnl and RSnl), optimism and pessimism (LOT-R), depression and anxiety (HADS), positive and negative affect (PANAS), and pain (VAS). RESULTS: Receiver operating characteristic analyses for recognizing the absence of depression and anxiety (HADS-score≤7) revealed better accuracy (P=0.038) for the BRSnl (AUC=0.84; p<0.0001) than for the RSnl (AUC=0.68; P=0.017). The scales correlated moderately at baseline (rs=0.35; p=0.026), and at four-week follow-up (rs=0.50; p=0.004). The RSnl was positively associated with positive outcomes (optimism and positive affect), and the BRSnl positively with positive outcomes, and negatively with negative outcomes (pessimism, anxiety and negative affect). The RSnl showed a better four-week test-retest reliability (ICC, 0.94; 95% CI, 0.87 to 0.97) than the BRSnl (0.66; 95% CI, 0.29 to.83). LIMITATIONS: Short study duration, a relatively small sample. CONCLUSION: The BRSnl showed better performance in detecting people without depression and anxiety than the RSnl, and performed better on construct validity.

Familial liability to psychosis is associated with attenuated dopamine stress signaling in ventromedial prefrontal cortex.

OBJECTIVE: Patients diagnosed with a psychotic disorder and their first-degree relatives display increased reactivity to stress. Theory predicts that experience of psychosocial stress is associated both with ventromedial prefrontal and mesolimbic dopamine neurotransmission. However, while there is evidence of aberrant striatal dopamine processing in psychotic disorder, the role of the prefrontal cortex remains under-researched. This study aimed at investigating stress-induced in vivo dopamine release in ventromedial prefrontal cortex (vmPFC) of individuals at familial risk for psychosis. METHOD: Fourteen healthy first-degree relatives of patients with a diagnosis of psychotic disorder and 10 control subjects underwent a single dynamic positron emission tomography (PET) scanning session after intravenous administration of 183.2 (SD = 7.6) MBq [(18)F]fallypride. Psychosocial stress was initiated at 100 min postinjection using a computerized mental arithmetic task with social evaluative threat components. PET data were analyzed using the linearized simplified reference region model. Regression analyses were performed to compare the spatial extent of task-related ligand displacement between control subjects and relatives and to find how it related to self-rated experiences of psychosocial stress and psychosis. RESULTS: First-degree relatives displayed hyporeactive dopamine signaling in the vmPFC in response to stress. Increased levels of subjectively rated stress were associated with increased intensity of psychotic experiences. This effect was particularly pronounced in first-degree relatives. CONCLUSION: Although previous studies have hypothesized a role for prefrontal dopamine dysfunction in psychosis, this study, to our knowledge, is the first in vivo human imaging study showing attenuated (ie, hyporeactive) dopamine stress neuromodulation in vmPFC of individuals at familial risk for psychosis.

COMT Val158Met genotype selectively alters prefrontal [18F]fallypride displacement and subjective feelings of stress in response to a psychosocial stress challenge.

Catechol-O-methyltransferase (COMT) plays an essential role in degradation of extracellular dopamine in prefrontal regions of the brain. Although a polymorphism in this gene, COMT Val(158)Met, affects human behavior in response to stress little is known about its effect on dopaminergic activity associated with the human stress response, which may be of interest for stress-related psychiatric disorders such as psychosis. We aimed to investigate the effect of variations in COMT genotype on in vivo measures of stress-induced prefrontal cortex (PFC) dopaminergic processing and subjective stress responses. A combined sample of healthy controls and healthy first-degree relatives of psychosis patients (n = 26) were subjected to an [(18)F]fallypride Positron Emission Tomography scan. Psychosocial stress during the scan was induced using the Montreal Imaging Stress Task and subjective stress was assessed every 12 minutes. Parametric t-maps, generated using the linear extension of the simplified reference region model, revealed an effect of COMT genotype on the spatial extent of [(18)F]fallypride displacement. Detected effects of exposure to psychosocial stress were unilateral and remained restricted to the left superior and right inferior frontal gyrus, with Met-hetero- and homozygotes showing less [(18)F]fallypride displacement than Val-homozygotes. Additionally, Met-hetero- and homozygotes experienced larger subjective stress responses than Val-homozygotes. The direction of the effects remained the same when the data was analyzed separately for controls and first-degree relatives. The human stress response may be mediated in part by COMT-dependent dopaminergic PFC activity, providing speculation for the neurobiology underlying COMT-dependent differences in human behaviour following stress. Implications of these results for stress-related psychopathology and models of dopaminergic functioning are discussed.

Delta-9-tetrahydrocannabinol-induced dopamine release as a function of psychosis risk: 18F-fallypride positron emission tomography study.

Cannabis use is associated with psychosis, particularly in those with expression of, or vulnerability for, psychotic illness. The biological underpinnings of these differential associations, however, remain largely unknown. We used Positron Emission Tomography and (18)F-fallypride to test the hypothesis that genetic risk for psychosis is expressed by differential induction of dopamine release by Δ(9)-THC (delta-9-tetrahydrocannabinol, the main psychoactive ingredient of cannabis). In a single dynamic PET scanning session, striatal dopamine release after pulmonary administration of Δ(9)-THC was measured in 9 healthy cannabis users (average risk psychotic disorder), 8 patients with psychotic disorder (high risk psychotic disorder) and 7 un-related first-degree relatives (intermediate risk psychotic disorder). PET data were analyzed applying the linear extension of the simplified reference region model (LSRRM), which accounts for time-dependent changes in (18)F-fallypride displacement. Voxel-based statistical maps, representing specific D2/3 binding changes, were computed to localize areas with increased ligand displacement after Δ(9)-THC administration, reflecting dopamine release. While Δ(9)-THC was not associated with dopamine release in the control group, significant ligand displacement induced by Δ(9)-THC in striatal subregions, indicative of dopamine release, was detected in both patients and relatives. This was most pronounced in caudate nucleus. This is the first study to demonstrate differential sensitivity to Δ(9)-THC in terms of increased endogenous dopamine release in individuals at risk for psychosis.