The Mms22-Rtt107 axis dampens the DNA damage checkpoint by reducing the stability of the Rad9 checkpoint mediator.

The DNA damage checkpoint is a highly conserved signaling pathway induced by genotoxin exposure or endogenous genome stress. It alters many cellular processes such as arresting the cell cycle progression and increasing DNA repair capacities. However, cells can downregulate the checkpoint after prolonged stress exposure to allow continued growth and alternative repair. Strategies that can dampen the DNA damage checkpoint are not well understood. Here, we report that budding yeast employs a pathway composed of the scaffold protein Rtt107, its binding partner Mms22, and an Mms22-associated ubiquitin ligase complex to downregulate the DNA damage checkpoint. Mechanistically, this pathway promotes the proteasomal degradation of a key checkpoint factor, Rad9. Furthermore, Rtt107 binding to Mms22 helps to enrich the ubiquitin ligase complex on chromatin and target the chromatin-bound form of Rad9. Finally, we provide evidence that the Rtt107-Mms22 axis operates in parallel with the Rtt107-Slx4 axis, which displaces Rad9 from chromatin. We thus propose that Rtt107 enables a bifurcated "anti-Rad9" strategy to optimally downregulate the DNA damage checkpoint.

Savoring changes novel positive mindset targets of GAD treatment: Optimism, prioritizing positivity, kill-joy thinking, and worry mediation.

This study analyzed effects of savoring on unstudied positive mindset targets of generalized anxiety disorder (GAD) treatment (ClinicalTrials.gov: NCT05040061). 85 students with GAD were randomly assigned to one of two ecological momentary interventions (EMIs) on smartphone for seven days. The SkillJoy EMI promoted practices for savoring positive emotions. An active control EMI mirrored SkillJoy, yet did not include savoring or positive emotion. Optimism, worry, kill-joy thinking (lessening positive emotion with cognition), and prioritization of positive emotion activities and goals were assessed at pre-trial, eighth-day, post-trial, and 30th-day follow-up. Savoring was assessed pre-trial and fifth-day mid-trial. Longitudinal linear mixed models and simple slope analyses examined change between and within conditions. Bias-corrected bootstrapping path analysis examined mediation of worry change by increased savoring. SkillJoy led to significantly greater increases in both optimism and prioritizing positivity than the control from pre-trial to post-trial and pre-trial to follow-up. Both interventions significantly reduced kill-joy thinking at both timepoints with Skilljoy leading to marginally greater change at post-trial. Pre- to mid-trial increases in savoring mediated the relationships between treatment condition and reductions in worry at both post-trial and follow-up.

Srs2 binding to PCNA and its sumoylation contribute to RPA antagonism during the DNA damage response.

Activation of the DNA damage checkpoint upon genotoxin treatment induces a multitude of cellular changes, such as cell cycle arrest, to cope with genome stress. After prolonged genotoxin treatment, the checkpoint can be downregulated to allow cell cycle and growth resumption. In yeast, downregulation of the DNA damage checkpoint requires the Srs2 DNA helicase, which removes the ssDNA binding complex RPA and the associated Mec1 checkpoint kinase from DNA, thus dampening Mec1 activation. However, it is unclear whether the 'anti-checkpoint' role of Srs2 is temporally and spatially regulated to both allow timely checkpoint termination and to prevent superfluous RPA removal. Here we address this question by examining regulatory elements of Srs2, including its phosphorylation, sumoylation, and protein-interaction sites. Our genetic analyses and checkpoint level assessment suggest that the RPA countering role of Srs2 is promoted by Srs2 binding to PCNA, which is known to recruit Srs2 to subsets of ssDNA regions. RPA antagonism is further fostered by Srs2 sumoylation, which we found depends on the Srs2-PCNA interaction. Srs2 sumoylation is additionally reliant on Mec1 and peaks after Mec1 activity reaches maximal levels. Collectively, our data provide evidence for a two-step model wherein checkpoint downregulation is facilitated by PCNA-mediated Srs2 recruitment to ssDNA-RPA filaments and the subsequent Srs2 sumoylation stimulated upon Mec1 hyperactivation. We propose that this mechanism allows Mec1 hyperactivation to trigger checkpoint recovery.

The potential of Future Event Specificity Training (FEST) to decrease anhedonia and dampening of positive emotions: A randomised controlled trial.

Impaired episodic future thinking (EFT), as reflected in reduced specificity, low levels of detail and less use of mental imagery, has been associated with depressive symptomatology. The beneficial impact of Future Event Specificity Training (FEST) on impaired EFT has recently been demonstrated, as well as on anhedonia, the core symptom of depression reflecting low positive affect. The current study aimed to replicate these previous findings. In addition, this study is the first to examine the potential of FEST to reduce engagement in dampening, a maladaptive response style characterised by reducing the intensity and/or frequency of positive emotional states, which is linked to depressive symptoms and anhedonia. An RCT (FEST vs. waitlist control) was conducted in a large sample of Dutch-speaking undergraduate students (N = 155). In line with prior research, FEST resulted in significant improvements in EFT features. However, likely related to limited room for change detection, no significant changes were found in anhedonia and dampening. In the light of the positive impact of FEST on several EFT features, future studies should address methodological issues to create optimal conditions for potential change detection. Finally, further examination of the proposed theoretical change mechanisms aimed to reduce anhedonia and dampening is warranted.

XIST directly regulates X-linked and autosomal genes in naive human pluripotent cells.

X chromosome inactivation (XCI) serves as a paradigm for RNA-mediated regulation of gene expression, wherein the long non-coding RNA XIST spreads across the X chromosome in cis to mediate gene silencing chromosome-wide. In female naive human pluripotent stem cells (hPSCs), XIST is in a dispersed configuration, and XCI does not occur, raising questions about XIST's function. We found that XIST spreads across the X chromosome and induces dampening of X-linked gene expression in naive hPSCs. Surprisingly, XIST also targets specific autosomal regions, where it induces repressive chromatin changes and gene expression dampening. Thereby, XIST equalizes X-linked gene dosage between male and female cells while inducing differences in autosomes. The dispersed Xist configuration and autosomal localization also occur transiently during XCI initiation in mouse PSCs. Together, our study identifies XIST as the regulator of X chromosome dampening, uncovers an evolutionarily conserved trans-acting role of XIST/Xist, and reveals a correlation between XIST/Xist dispersal and autosomal targeting.

Emotional dampening in hypertension: Impaired recognition of implicit emotional content in auditory and cross-modal stimuli.

Research shows a reduced responsivity to implicit as well as explicit facial emotion recognition (emotional dampening) in prehypertensives and hypertensives. This study explored auditory and audiovisual emotion recognition in prehypertensives and hypertensives. Participants (N = 175) who were normotensives, prehypertensives, and hypertensives (n = 57, 58, and 60, respectively) completed an auditory implicit task (matching auditory target with auditory distractors) and two cross-modal implicit tasks (matching visual target with auditory distractors, and vice-versa), and an auditory explicit task (labelling emotions in audio-clips). Findings showed an aberrant speed-accuracy trade-off, where prehypertensives focused more on accuracy at the cost of speed while hypertensives showed the opposite. Discriminant function analysis revealed that blood pressure (BP)-associated emotional dampening is a highly specific but moderately sensitive correlate of hypertension. Our study highlights that prehypertensives and hypertensives demonstrate emotional dampening in implicit (but not explicit) auditory emotion recognition and a greater deficit for auditory than visual recognition of implicit emotions. Findings show emotional dampening as an observable correlate of elevated BP and hypertension.

Fear of Happiness Predicts Concurrent but not Prospective Depressive Symptoms in Adolescents.

Background: It is increasingly recognised that the study of responses to positive emotions significantly contributes to our understanding of psychopathology. Notably, positive emotions are not necessarily experienced as pleasurable. Instead, some believe that experiencing happiness may have negative consequences, referred to as fear of happiness (FOH), or they experience a fear of losing control over positive emotions (FOLC). According to reward devaluation theory, such an association of positivity with negative outcomes will result in positive stimuli being devalued over time, contributing to or maintaining depressive symptoms. The prospective relationship between fears of positivity and depressive symptoms is yet to be examined in adolescents. The present longitudinal study investigated whether FOH and FOLC prospectively predict depressive symptoms. Method: 128 adolescents between 16-18 years of age (M = 16.87, SD = 0.80) recruited from two secondary schools in Flanders, Belgium, completed measures of depressive symptoms (Depression Anxiety Stress Scales) including consummatory anhedonia, FOH (Fear of Happiness Scale), and FOLC (Affective Control Scale) in their classroom at baseline and 2-months follow-up. Regression analyses were performed to test the association between FOH, FOLC, and depressive symptoms. Results: FOH concurrently, but not prospectively, predicted depressive symptoms. There was no significant association between FOH and consummatory anhedonia. FOLC was not a significant predictor of depressive symptoms or consummatory anhedonia. Conclusion: These findings suggest that FOH may only be concurrently related to depressive symptoms. Considering prior findings in adults, future research should investigate the association of FOH with anticipatory anhedonia in adolescents.

Relieving the Gambling Itch Through Alcohol Consumption: The Impact of COVID-19 Restrictions on Australian Casino Patrons.

This paper extends our understanding of how casino patrons are affected by COVID-19 restrictions and how they cope by substituting gambling with alcohol consumption. We conducted two studies using a nationwide survey sample collected in Australia during the pandemic lockdown. Study 1 compares the casino patrons with two reference groups (other gambling patrons and non-gambling individuals) and investigates the lockdown restrictions on respondents' relational strength, and their potential impact on mental health and future prospects. Study 2 applies the stress-response dampening model (SRD) and tests how respondents used alcohol consumption to cope with the lack of access to casinos during the lockdown. The results from Study 1 suggest that lockdown restrictions on respondents' relational strength have significant negative impacts on anxiety, life satisfaction and post-pandemic outlook. Study 2 finds that casino patrons substituted gambling with alcohol consumption during the lockdown, with increased alcohol consumption negatively related to life satisfaction. Paradoxically, Australian gambling venue owners may not be adversely affected as many also run liquor retail operations.

Linking Blood Pressure-Associated Emotional Dampening to Trait Empathy.

Gradual and sustained increases in resting blood pressure are accompanied by gradual and sustained reductions in the capacity to consciously experience several affective and somatosensory processes. Burgeoning theory suggests that this phenomenon, termed cardiovascular emotional dampening, contributes to heart disease risk by interfering with our ability to effectively respond to environmental demands. Interpersonal relationships are contexts in which this risk cascade likely occurs, but prior researchers have paid little attention to how emotional dampening might influence these relationships. As empathy is a construct used to describe facets of emotion-linked responding that facilitate interpersonal relationships, if emotional dampening influences interpersonal relationships, then we might expect resting blood pressure to covary with measures of empathy as it does with other previously studied aspects of affective responding. We recruited 175 healthy undergraduate college student participants (120 Women; M age = 19.17, SD age = 2.08) to complete a counterbalanced procedure in which we measured resting blood pressure and related it to participants' responses on the Toronto Alexithymia Scale, the Questionnaire of Cognitive and Affective Empathy, and a demographic survey. Bivariate comparisons revealed a significant inverse relationship between average resting systolic blood pressure (SBP) and cognitive empathy, as well as a significant inverse relationship between SBP and affective empathy. Multiple regression analyses revealed that SBP remained a significant predictor of cognitive empathy, but not affective empathy, after controlling for related covariates (i.e., sex, age, and alexithymia). SBP predicted cognitive empathy such that higher SBP was associated with lower cognitive empathy. Thus, people with higher resting blood pressures might experience increased interpersonal distress because of a reduced capacity for empathetic accuracy and perspective-taking. We discuss the implications and future directions of these findings.

A network analytic investigation of avoidance, dampening, and devaluation of positivity.

BACKGROUND AND OBJECTIVES: Reward Devaluation Theory suggests that devaluation of positivity may be integral in understanding depression (Winer & Salem, 2016). Specifically, the anticipatory (e.g., fear of happiness) and responsive (e.g., dampening) behaviors related to the processing of positivity may play a role in the development and maintenance of depression. METHODS: The goal of this study was to examine the potential overlap between measures that operationalize positivity avoidance, two Fear of Happiness Scales (Gilbert et al., 2012; Joshanloo, 2013), as well as positivity dampening, measured via the dampening subscale of the Responses to Positive Affect Questionnaire (Feldman et al., 2008). Network and community analyses were employed to examine the extent to which the items of these measures clustered into their parent measures and investigate the dynamic interactions between items. RESULTS: The results of the community analysis revealed that the three self-report measures overall clustered into their parent measures, except for the Gilbert et al. (2012) Fear of Happiness Scale, which clustered into two separate communities. The most influential nodes represented the concept that good feelings are often followed by negative outcomes. Additionally, nodes related to the theme of fear of letting oneself become happy emerged as the strongest bridge nodes. LIMITATIONS: One limitation of this study is the use of a cross-sectional design; thus, causality cannot be inferred, but the results can guide future longitudinal network designs. CONCLUSIONS: These findings demonstrate how anticipatory avoidance and responsive dampening may influence depression, thus providing evidence for unique targets for treatment.

Validez de constructo y propiedades psicométricas del cuestionario “Respuestas al afecto positivo” (RAP) / Construct validity and psychometric properties of the questionnaire "Responses to Positive Affect" (RAP)

Los estudios constatan el papel de la rumia depresiva como un amplificador del estado de ánimo negativo, sin embargo, se conoce menos sobre la rumia relacionada con el afecto positivo. Presentamos la validez de constructo y propiedades psicométricas del cuestionario “Respuestas al afecto positivo” (RAP) en una muestra de 302 personas de la población general (55,2% mujeres), con edades entre los 18 y 68 años (M= 28,6; DT= 12,0). Los análisis factorial exploratorio y confirmatorio indican una estructura de dos factores: rumia positiva centrada en la emoción y en la persona (α= 0,88) y amortiguación (α= 0,83), ambos con una adecuada invarianza configural, métrica y escalar por sexo. Los dos factores presentan una adecuada validez convergente, discriminante e incremental con constructos relacionados con el afecto negativo y positivo. Los resultados se discuten atendiendo a los estudios revisados y se propone el RAP como instrumento de evaluación en procedimientos terapéuticos que tratan de potenciar el afecto positivo y el bienestar psicológico. (AU)

Previous studies confirm the role of depressive rumination in the exacerbation of negative mood. However, less is known about rumination in relation to positive affect. We present the construct validity and psychometric properties of the Responses to Positive Affect (RAP) questionnaire in a sample of 302 people from the general population (55.2% female), aged 18-68 years (M= 28.6, SD= 12.0). Exploratory and confirmatory factor analyses indicate a two-factor structure: emotion- and person-centered positive rumination (α= .88) and buffering (α= .83), both with adequate configural, metric and scalar invariance by sex. The two factors present adequate convergent, discriminant and incremental validity with constructs related to negative and positive affect. The results are discussed according to the studies reviewed and the RAP is proposed as an assessment instrument in therapeutic procedures that seek to enhance positive affect and psychological wellbeing. (AU)

Subjective perception of objects depends on the interaction between the validity of context-based expectations and signal reliability.

Predictive coding theories of visual perception assume that expectations based on prior knowledge modulate the processing of information. However, the underlying mechanisms remain debated. Some accounts propose that expectations enhance the perception of expected relative to unexpected stimuli while others assume the opposite. Recently, the opposing process theory suggested that enhanced perception of expected vs. unexpected stimuli may occur alternatively depending upon the reliability of the visual signal. When the signal is noisy, perception would be biassed toward what is expected since anything else may be too noisy to be resolved. When the signal is unambiguous, perception would be biassed toward what diverges from expectations and is more informative. Our study tested this hypothesis, using a perceptual matching task to investigate the influence of expectations on the perceived sharpness of objects in context. Participants saw two blurred images depicting the same object and had to adjust the blur level of one object to match the blur level of the other one. We manipulated the validity of expectations about objects by varying their scene context (congruent or incongruent context leading to valid or invalid expectations about the object). We also manipulated the reliability of the visual signal by varying the initial blur level of object pairs. Results showed that expectations validity differentially affected the perception of objects depending on signal reliability. Perception of validly expected objects was enhanced (sharpened) relative to unexpected objects when visual inputs were unreliable while this effect reversed to the benefit of unexpected objects when the signal was more reliable.

Behavioural approach-avoidance tendencies among individuals with elevated blood pressure.

Emotional dampening (blunted responses to affective stimuli or experiences) has been reported in individuals with clinical and subclinical levels of elevated blood pressure (BP). Our aim in the present study was to explore how the basic motivational systems of approach and avoidance to positively- and negatively-valenced stimuli are affected in elevated BP. High BP (n = 27) and Low BP (n = 29) participants completed an approach-avoidance task. In this task, participants pulled the joystick towards them when viewing a happy face (approach) and pushing it away when viewing an angry face (avoid) in the congruent condition, and reversed these action-to-emotion pairings in the incongruent condition. A mixed-design ANOVA revealed a significant main effect of condition, such that overall participants were faster across trials in the congruent than trials of the incongruent condition. There was also an emotion x BP interaction. Among the Low BP group, there were no RT differences to happy and angry expressions (across congruent and incongruent conditions) but those with High BP were quicker to respond to actions paired with angry than happy facial expressions (across conditions). Findings suggest that valence-specific motivational reactions are not dampened with an increase in BP, and are rather sensitized for the negative emotion of anger. Supplementary information: The online version contains supplementary material available at 10.1007/s12144-023-04337-2.

Role of positive emotion regulation strategies in the association between childhood trauma and posttraumatic stress disorder among trauma-exposed individuals who use substances.

BACKGROUND: The co-occurrence of childhood trauma and posttraumatic stress disorder (PTSD) is highly prevalent and clinically significant. Existing research emphasizes the role of emotion regulation in the relation between childhood trauma and PTSD. Yet, research in this area has almost exclusively examined the influence of strategies aimed at regulating negative emotions, such as anger and sadness. OBJECTIVE: To extend existing research, the current study examined underlying roles of strategies for regulating positive emotions (i.e., self- and emotion-focused positive rumination and positive dampening) in the association between childhood trauma severity and PTSD symptoms. PARTICIPANTS AND SETTING: Participants were 320 trauma-exposed community individuals who reported past 30-day substance use (Mage = 35.78, 50.3% men, 81.6% white). METHOD: Analyses examined whether childhood trauma severity was indirectly related to PTSD symptoms through self-focused positive rumination, emotion-focused positive rumination, and positive dampening. RESULTS: Positive dampening, but not positive self- and emotion-focused positive rumination, indirectly explained associations between childhood trauma severity and PTSD symptoms (B = .17, SE = .03, 95% CI [.12, .24]). CONCLUSIONS: These findings highlight the potential utility of targeting positive dampening in the treatment of PTSD symptoms among individuals who use substances with a history of childhood trauma.

Correlates of Dampening and Savoring in Generalized Anxiety Disorder.

Chronic worry and generalized anxiety disorder (GAD) symptoms are associated with infrequent savoring, and high dampening, of positive emotions. The goal of the present study was to investigate the indirect role of GAD-relevant processes, including intolerance of uncertainty (IU), fear of negative emotional contrasts, and negative beliefs about positive emotion and its regulation, in the relationship between GAD symptom severity and the tendency to engage in dampening and not savor positive emotions. Community participants (N = 233) completed questionnaires online. In separate models, IU, fear of negative emotional contrasts, and negative beliefs about positive emotion and its regulation fully mediated the relationships between GAD symptom severity and greater dampening and lower savoring. However, controlling for depression, only IU remained a significant mediator. A post hoc latent analysis of the mediators provided support for an underlying construct that may reflect intolerance of uncomfortable states. Intolerance of uncomfortable states was found to significantly mediate the relationship between GAD symptoms and greater dampening and lower savoring. Difficulty withstanding uncertainty may be particularly relevant in understanding why people with elevated GAD symptoms engage in efforts to avoid experiencing positive emotions. Further, the findings suggest that there may be a common factor underlying a variety of GAD-associated constructs reflecting a broad intolerance of uncomfortable inner states. Theoretical and clinical implications are discussed. Supplementary Information: The online version contains supplementary material available at 10.1007/s41811-022-00145-x.

Modulation of Cellular Circadian Rhythms by Secondary Metabolites of Lichens.

Background: Most mammalian cells harbor molecular circadian clocks that synchronize physiological functions with the 24-h day-night cycle. Disruption of circadian rhythms, through genetic or environmental changes, promotes the development of disorders like obesity, cardiovascular diseases, and cancer. At the cellular level, circadian, mitotic, and redox cycles are functionally coupled. Evernic (EA) and usnic acid (UA), two lichen secondary metabolites, show various pharmacological activities including anti-oxidative, anti-inflammatory, and neuroprotective action. All these effects have likewise been associated with a functional circadian clock. Hypothesis/Purpose: To test, if the lichen compounds EA and UA modulate circadian clock function at the cellular level. Methods: We used three different cell lines and two circadian luminescence reporter systems for evaluating dose- and time-dependent effects of EA/UA treatment on cellular clock regulation at high temporal resolution. Output parameters studied were circadian luminescence rhythm period, amplitude, phase, and dampening rate. Results: Both compounds had marked effects on clock rhythm amplitudes and dampening independent of cell type, with UA generally showing a higher efficiency than EA. Only in fibroblast cells, significant effects on clock period were observed for UA treated cells showing shorter and EA treated cells showing longer period lengths. Transient treatment of mouse embryonic fibroblasts at different phases had only minor clock resetting effects for both compounds. Conclusion: Secondary metabolites of lichen alter cellular circadian clocks through amplitude reduction and increased rhythm dampening.

Does loneliness before the age of twelve indirectly affect impaired control over drinking, alcohol use, and problems through perceived stress?

Loneliness is the pain of feeling socially isolated from others (Russell et al., 1980). The Stress-Dampening Hypothesis (Marlatt, 1987; Sayette, 1993; Sher, 1987) posits that individuals drink to alleviate negative affect. To date, it has not been determined whether loneliness experienced as a child can indirectly influence at-risk patterns of alcohol use through the mediating mechanism of stress and impaired control. Impaired control over alcohol use (IC) is the difficulty adhering to one's own self-proscribed limits on drinking behaviors (Heather et al., 1993). Impaired control is an at-risk pattern of use that is particularly relevant to emerging adults. Methods: We examined the direct and indirect relationships between childhood loneliness, stress, IC, and alcohol-related problems with a structural equation model. In a college student sample, we utilized a (k = 20,000) bootstrap technique and a model indirect command in Mplus to examine potential mediational pathways. Cisgender sex was included as a covariate. Results: Loneliness was directly linked to stress as well as to alcohol-related problems. Higher levels of loneliness were indirectly linked to both more alcohol use and alcohol-related problems through more stress and in turn, more impaired control over drinking. Conclusions: The current study is consistent with the Stress Dampening Hypothesis (Marlatt, 1987; Sayette, 1993; Sher, 1987). Our findings suggest that therapeutic interventions combating loneliness in childhood may disrupt the stress-dampening pathway to dysregulated alcohol use in emerging adulthood.

Dampening of positive affect and depression: A meta-analysis of cross-sectional and longitudinal relationships.

Dampening responses to positive affect have been posited to confer vulnerability to depression, but longitudinal studies have not consistently shown dampening tendencies to predict follow-up depression. The cross-sectional, longitudinal, and cross-lagged relationships between dampening and depression were determined using meta-analytic methods. A systematic literature search of the PsycINFO and PubMed databases supplemented by Google Scholar yielded 60 samples suitable for inclusion in the cross-sectional analyses and 12 samples meeting criteria for the longitudinal analyses. In the first meta-analytic study to examine the relationship between dampening and depression, we found dampening to be associated with depression both cross-sectionally (r = .45) and prospectively (r = 0.34). Crucially, dampening at baseline remained a significant predictor of follow-up depression even after controlling for baseline levels of depression in cross-lagged analyses (ß = .09). A bidirectional effect was also found, with baseline levels of depression predicting follow-up tendencies to engage in dampening (r = 0.36). This relationship was again diminished but remained significant after controlling for initial levels of dampening (ß = .14). These results suggest that dampening responses to positive affect are a risk factor for the development of depression and highlight the importance of targeting dampening cognitions in treatment.

Resting (Tonic) Blood Pressure Is Associated With Sensitivity to Imagined and Acute Experiences of Social Pain: Evidence From Three Studies.

Social pain is a common experience that has potent implications for health. However, individuals differ in their sensitivity to social pain. Recent evidence suggests that sensitivity to social pain varies according to a biological factor that modulates sensitivity to physical pain: resting (tonic) blood pressure. The current studies extended this evidence by testing whether blood pressure relates to sensitivity to imagined (Study 1: N = 762, 51% female adults) and acute (Study 2, preregistered: N = 204, 57% female adults) experiences of social pain and whether associations extend to general emotional responding (Studies 1-3; Study 3: N = 162, 59% female adults). In line with prior evidence, results showed that higher resting blood pressure was associated with lower sensitivity to social pain. Moreover, associations regarding blood pressure and sensitivity to social pain did not appear to be explained by individual differences in general emotional responding. Findings appear to be compatible with the interpretation that social and physical pain share similar cardiovascular correlates and may be modulated by convergent interoceptive pathways.

Mechanisms of energy dissipation and relationship with tissue composition in human meniscus.

OBJECTIVE: The human meniscus is essential in maintaining proper knee joint function. The meniscus absorbs shock, distributes loads, and stabilizes the knee joint to prevent the onset of osteoarthritis. The extent of its shock-absorbing role can be estimated by measuring the energy dissipated by the meniscus during cyclic mechanical loading. METHODS: Samples were prepared from the central and horn regions of medial and lateral human menisci from 8 donors (both knees for total of 16 samples). Cyclic compression tests at several compression strains and frequencies yielded the energy dissipated per tissue volume. A GEE regression model was used to investigate the effects of compression, meniscal side and region, and water content on energy dissipation in order to account for repeated measures within samples. RESULTS: Energy dissipation by the meniscus increased with compressive strain from ∼0.1 kJ/m3 (at 10% strain) to ∼10 kJ/m3 (at 20% strain) and decreased with loading frequency. Samples from the anterior region provided the largest energy dissipation when compared to central and posterior samples (P < 0.05). Water content for the 16 meniscal tissues was 77.9 (C.I. 72.0-83.8%) of the total tissue mass. A negative correlation was found between energy dissipation and water content (P < 0.05). CONCLUSION: The extent of energy dissipated by the meniscus is inversely related to loading frequency and meniscal water content.