White matter microstructure organization across the transition to fatherhood.

The transition to parenthood remains an understudied window of potential neuroplasticity in the adult brain. White matter microstructural (WMM) organization, which reflects structural connectivity in the brain, has shown plasticity across the lifespan. No studies have examined how WMM organization changes from the prenatal to postpartum period in men becoming fathers. This study investigates WMM organization in men transitioning to first-time fatherhood. We performed diffusion-weighted imaging to identify differences in WMM organization, as indexed by fractional anisotropy (FA). We also investigated whether FA changes were associated with fathers' postpartum mental health. Associations between mental health and WMM organization have not been rarely examined in parents, who may be vulnerable to mental health problems. Fathers exhibited reduced FA at the whole-brain level, especially in the cingulum, a tract associated with emotional regulation. Fathers also displayed reduced FA in the corpus callosum, especially in the forceps minor, which is implicated in cognitive functioning. Postpartum depressive symptoms were linked with increases and decreases in FA, but FA was not correlated with perceived or parenting stress. Findings provide novel insight into fathers' WMM organization during the transition to parenthood and suggest postpartum depression may be linked with fathers' neuroplasticity during the transition to parenthood.

Neural correlates of inhibitory control in the context of infant cry and paternal postpartum mental health.

BACKGROUND: Inhibitory control, a form of self-regulation, may support sensitive parenting, but has been understudied in new fathers despite their pronounced risk for stress and mental health challenges. METHODS: This study probed the neural correlates of inhibitory control and its associations to first-time fathers' postpartum mental health, focusing on depressive symptoms, state anxiety, and perceived stress. Six months after their child's birth, 38 fathers self-reported on their mood, anxiety, and stress, and performed a Go/No-Go fMRI task while listening to three sets of sounds (infant cry, pink noise, and silence). RESULTS: Fathers' behavioral inhibition accuracy was consistent across the sound conditions, but their patterns of neural activation varied. Compared to the pink noise condition, fathers showed heightened engagement in prefrontal regulatory regions when self-regulating during the infant cry and silent conditions. When examining correct trials only, results in visual motor area and primary somatosensory cortex emerged only for infant cry and not for pink noise and silence. Moreover, fathers reporting higher levels of postpartum depression, state anxiety, and perceived stress showed greater activation in prefrontal regions when inhibiting during infant cry or silence. CONCLUSION: This study is the first to underscore the complex interplay between the neural mechanisms related to inhibitory control and postpartum mental health and stress across varied auditory context, laying the groundwork for future research.

Maternal prenatal social contact during the COVID-19 pandemic predicts infant birth weight.

BACKGROUND: Social connectedness and mental health have been associated with infant birth weight, and both were compromised by the COVID-19 pandemic. AIMS: We sought to examine whether changes in maternal prenatal social contact due to the COVID-19 pandemic were associated with infant birth weight and if maternal prenatal mental health mediated this association. STUDY DESIGN: A longitudinal study of mothers and their infants born during the first wave of the COVID-19 pandemic. SUBJECTS: The sample consisted of 282 United States-based mother-infant dyads. OUTCOME MEASURES: Depressive symptoms were measured with the Beck Depression Inventory-II, anxiety was measured with the State Anxiety Inventory, and stress was measured using the Perceived Stress Scale 14. We also asked participants about pandemic-related changes in social contact across various domains. Adjusted birth weight was calculated from birth records or participant-report when birth records were unavailable. RESULTS: Decreases in social contact during the pandemic were associated with lower adjusted infant birth weight (B = 76.82, SE = 35.82, p = .035). This association was mediated by maternal prenatal depressive symptoms [Effect = 15.06, 95 % CI (0.19, 35.58)] but not by prenatal anxiety [95 % CI (-0.02, 32.38)] or stress [95 % CI (-0.31, 26.19)]. CONCLUSION: These findings highlight concerns for both mothers and infants in the wake of the COVID-19 pandemic, since birth weight can have long-term health implications and the social restructuring occasioned by the pandemic may lead to lasting changes in social behavior.

Prenatal testosterone synchrony in first-time parents predicts fathers' postpartum relationship quality.

There is evidence that men's testosterone levels decline across the transition to fatherhood and that this decline may reflect fathers' investment in the new family. There is also emerging evidence that cohabiting couples show synchrony or within-couple associations in testosterone levels during the perinatal period. Hormonal synchrony may act as a mechanism that supports fathers' biological preparation for parenthood, perhaps by facilitating perinatal declines in paternal testosterone. However, few studies have examined testosterone synchrony and change within couples. A sample of 97 U.S. couples expecting their first child provided testosterone samples during pregnancy, and of those couples, 78 couples also provided testosterone at seven months postpartum. Couples reported on relationship satisfaction both at prenatal and postpartum visits. Bayesian multilevel modeling revealed within-couple testosterone synchrony both during pregnancy and postpartum. Testosterone synchrony during pregnancy predicted a greater drop in fathers' testosterone levels from prenatal to postpartum and higher paternal postpartum relationship quality. Fathers' lower prenatal testosterone levels also subsequently predicted higher self-reported postpartum relationship quality for both parents. In sum, this study finds that couples' testosterone levels show synchrony across the transition to parenthood in ways that are associated with couple relationship quality and men's neuroendocrine preparation for fatherhood.

Prenatal prolactin predicts postnatal parenting attitudes and brain structure remodeling in first-time fathers.

Despite the important contributions that fathers make to parenting, the neurobiological underpinnings of men's adaptation to parenthood are still not well understood. The current study focuses on prolactin, a hormone that has been extensively linked with reproduction, lactation, and parental behavior in mothers. There is preliminary evidence that prolactin may also reflect the transition to sensitive fatherhood. We sampled prolactin in 91 first-time expectant fathers who participated in a laboratory visit along with their pregnant partners. Fathers' prolactin levels were correlated with their partners' prolactin levels. Men's prolactin levels during their partner's pregnancy were associated with their self-reported antenatal bonding to the unborn infant. Prenatal prolactin levels in fathers also predicted more positive attitudes toward fatherhood at three months postpartum, including lower parenting stress, greater enjoyment of the infant, and a more attunement-oriented parenting style. Within a smaller sample of 32 men who participated in MRI scanning before and after their child's birth, prenatal prolactin also predicted greater reductions in grey matter volume in the left posterior cingulate, left insula, and left nucleus accumbens. In conclusion, men's prenatal prolactin may reflect their perceptions of fatherhood and changes to their perinatal brain structure.

Fathers' subjective childbirth stress predicts depressive symptoms at six months postpartum.

BACKGROUND: Childbirth is a seminal experience in parents' lives. However, little research has investigated the link between fathers' birth experiences and their postpartum mental health. We hypothesized that a more subjectively stressful birth will predict greater self-reported depressive symptoms in fathers at six months postpartum. We also investigated the association between mode of delivery and paternal subjective stress. METHODS: Seventy-seven heterosexual fathers expecting their first child and cohabiting with their pregnant partners participated in the study. Depressive symptoms were assessed in pregnancy and again at six months postpartum. Subjective birth stress was measured within the first few days of the birth, and birth charts were collected to examine mode of delivery. RESULTS: Fathers' ratings of subjective birth stress significantly predicted postpartum depressive symptoms at six months postpartum. Subjective birth stress ratings varied significantly for fathers whose partners delivered via emergency cesarean section compared to those whose partners gave birth via both medicated and the unmedicated vaginal delivery. LIMITATIONS: The study was limited by its small community (non-clinical) sample, which was restricted to heterosexual, cohabitating couples. Additionally, births were mostly uncomplicated and only 14 mothers underwent emergency cesarean section. CONCLUSION: These findings highlight that the days immediately following childbirth are a window of opportunity for early intervention in new fathers at risk for postpartum depression.

Differences in infant negative affectivity during the COVID-19 pandemic.

This longitudinal study compared infant temperament rated at 3 months postpartum by 263 United-States-based women who gave birth during the COVID-19 pandemic and 72 who gave birth prior to the pandemic. All women completed questionnaires assessing perinatal mental health, social contact, and infant temperament. Mothers whose infants were born during the pandemic reported higher levels of infant negative affectivity as compared with mothers whose infants were born earlier (F(1, 324) = 18.28, p < .001), but did not differ in their ratings of surgency or effortful control. Maternal prenatal depressive symptoms, prenatal stress, and postpartum stress mediated differences in infant negative affectivity  between pandemic and pre-pandemic groups. Within the pandemic group, decreased postpartum social contact was associated with higher ratings of infant negative affectivity. These findings suggest that the pandemic has affected maternal perceptions of infant temperament, perinatal mental health, and social contact.

Este estudio longitudinal comparó el temperamento del infante evaluado a los tres meses después del parto por 263 mujeres con base en Estados Unidos, las cuales dieron a luz durante la pandemia del COVID-19 y 72 que dieron a luz antes de la pandemia. Todas las mujeres completaron cuestionarios para evaluar la salud mental perinatal, el contacto social y el temperamento del infante. Las madres cuyos infantes nacieron durante la pandemia reportaron más altos niveles de afectividad negativa del infante tal como se les comparó con madres cuyos infantes nacieron antes (F(1,324) = 18.28, p<.001), pero no difirieron en sus puntajes de rapidez y astucia o control esforzado. Los síntomas depresivos maternos mediaron la asociación entre la condición de pandemia y la afectividad negativa del infante. Dentro del grupo de pandemia, la baja en el contacto social posterior al parto fue asociada con más altos puntajes en la afectividad negativa del infante. Estos resultados proponen que la pandemia ha afectado las percepciones mentales de la salud mental y el contacto social del temperamento perinatal del infante.

Cette étude longitudinale a comparé le tempérament du nourrisson évalué à trois mois postpartum par 263 femmes basées aux Etats-Unis d'Amérique ayant donné naissance durant la pandémie du COVD-19 et 72 femmes ayant donné naissance avant la pandémie. Toutes les femmes ont rempli des questionnaires évaluant la santé mentale périnatale, le contact social et le tempérament du nourrisson. Les mères dont les nourrissons étaient nés durant la pandémie ont fait état de niveaux plus élevés d'affectivité négative du bébé comparées aux mères dont les bébés étaient nés avant (F(1 324) = 18,28, p <,001), mais n'ont pas divergé dans leurs évaluations du dynamisme ou du contrôle efficace. Les symptômes dépressifs maternels ont médiatisé le lien entre le statue pandémique et l'affectivité négative du nourrisson. Au sein du groupe pandémique le contact social postpartum décru était lié à des évaluations plus élevées de l'affectivité négative du nourrisson. Ces résultats suggèrent que la pandémie a affecté les perceptions maternelles du tempérament du bébé, la santé mentale périnatale et le contact social.

First-time fathers show longitudinal gray matter cortical volume reductions: evidence from two international samples.

Emerging evidence points to the transition to parenthood as a critical window for adult neural plasticity. Studying fathers offers a unique opportunity to explore how parenting experience can shape the human brain when pregnancy is not directly experienced. Yet very few studies have examined the neuroanatomic adaptations of men transitioning into fatherhood. The present study reports on an international collaboration between two laboratories, one in Spain and the other in California (United States), that have prospectively collected structural neuroimaging data in 20 expectant fathers before and after the birth of their first child. The Spanish sample also included a control group of 17 childless men. We tested whether the transition into fatherhood entailed anatomical changes in brain cortical volume, thickness, and area, and subcortical volumes. We found overlapping trends of cortical volume reductions within the default mode network and visual networks and preservation of subcortical structures across both samples of first-time fathers, which persisted after controlling for fathers' and children's age at the postnatal scan. This study provides convergent evidence for cortical structural changes in fathers, supporting the possibility that the transition to fatherhood may represent a meaningful window of experience-induced structural neuroplasticity in males.

Recent Neuroscience Advances in Human Parenting.

The transition to parenthood entails brain adaptations to the demands of caring for a newborn. This chapter reviews recent neuroscience findings on human parenting, focusing on neuroimaging studies. First, we describe the brain circuits underlying human maternal behavior, which comprise ancient subcortical circuits and more sophisticated cortical regions. Then, we present the short-term and long-term functional and structural brain adaptations that characterize the transition to motherhood, discuss the long-term effects of parenthood on the brain, and propose several underlying neural mechanisms. We also review neuroimaging findings in biological fathers and alloparents (such as other relatives or adoptive parents), who engage in parenting without directly experiencing pregnancy or childbirth. Finally, we describe perinatal mental illnesses and discuss the neural responses associated with such disorders. To date, studies indicate that parenthood is a period of enhanced brain plasticity within brain areas critical for cognitive and social processing and that both parenting experience and gestational-related factors can prime such plasticity.

The transition to parenthood in obstetrics: enhancing prenatal care for 2-generation impact.

Obstetrics, the specialty overseeing infant and parent health before birth, could be expanded to address the interrelated areas of parents' prenatal impact on children's brain development and their own psychosocial needs during a time of immense change and neuroplasticity. Obstetrics is primed for the shift that is happening in pediatrics, which is moving from its traditional focus on physical health to a coordinated, whole-child, 2- or multigeneration approach. Pediatric care now includes developmental screening, parenting education, parent coaching, access to developmental specialists, brain-building caregiving skills, linkages to community resources, and tiered interventions with psychologists. Drawing on decades of developmental origins of health and disease research highlighting the prenatal beginnings of future health and new studies on the transition to parenthood describing adult development from pregnancy to early postpartum, we have proposed that, similar to pediatrics, the integration of education and intervention strategies into the prenatal care ecosystem should be tested for its potential to improve child cognitive and social-emotional development and parental mental health. Pediatric care programs can serve as models of change for the systematic development, testing and, incorporation of new content into prenatal care as universal, first-tier treatment and evidenced-based, triaged interventions according to the level of need. To promote optimal beginnings for the whole family, we have proposed an augmented prenatal care ecosystem that aligns with, and could build on, current major efforts to enhance perinatal care individualization through consideration of medical, social, and structural determinants of health.

Delivering alone in a pandemic: Anticipated changes to partner presence at birth are associated with prenatal distress.

INTRODUCTION: The COVID-19 pandemic has impacted individuals across the world, and in particular, dramatically affected the experience of pregnancy and childbirth for many expectant mothers. The transition to parenthood is a time of increased risk for mental health problems, and maternal prenatal stress is associated with long-term maternal and infant health implications. The current study explored whether COVID-19 related changes to mothers' childbirth plans and prenatal health care experiences during the first wave of pandemic lockdowns in the U.S. were associated with self-reported depression, anxiety, and stress. METHOD: In spring 2020; we surveyed 641 pregnant women on their pregnancy and birth plans, as well as their mental health, during the COVID-19 pandemic. RESULTS: Women anticipating changes to the presence of their partner at birth also reported heightened symptoms of depression, anxiety, and stress. Additionally, women who anticipated changes to the timing of delivery reported both higher anxiety and higher perceived stress. DISCUSSION: These findings extend initial work suggesting increased risk for mental health problems in pregnant women during the COVID-19 pandemic by highlighting specific pandemic-related disruptions to pregnancy and birth that may have contributed to prenatal distress. Monitoring and intervention for these mothers and their infants are warranted. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Physical touch during father-infant interactions is associated with paternal oxytocin levels.

INTRODUCTION: Physical connection, particularly parent-to-infant touch, is critical for the well-being of infants and may support the development of the parent-infant bond. Physical touch has also been found to stimulate oxytocin levels. This study tested whether fathers' micro-coded touch behaviors during parent-child interaction predicted their subsequent oxytocin levels. We also compared two widely-used methods of oxytocin immunoassay that have been found to yield discrepant results in past studies. METHODS: Among 45 fathers and their six-month-old infants, we micro-coded paternal physical touch at 1/10 s intervals during a laboratory-based free-play interaction. Paternal oxytocin was measured via blood plasma and was processed both with and without the extraction step prior to immunoassay so that results from the two methods could be compared. RESULTS: Unextracted and extracted oxytocin were moderately correlated within our sample. Fathers who engaged in more playful proprioceptive touch showed higher levels of both unextracted and extracted oxytocin. Gentle affectionate touch and functional proprioceptive touch predicted higher unextracted but not extracted oxytocin levels. Fathers who did not engage in physical touch showed lower levels of both unextracted and extracted oxytocin. CONCLUSION: Results are consistent with previous work showing that physical touch, particularly playful proprioceptive touch, is associated with higher oxytocin levels in fathers. These results replicate previous research using unextracted oxytocin measurement, and extend this work, showing that many but not all associations hold when using the more rigorous method of extraction when measuring oxytocin.

Early effects of the COVID-19 pandemic on fertility preferences in the United States: an exploratory study.

OBJECTIVE: To explore early disparate impacts of the COVID-19 pandemic on fertility preferences DESIGN: Cross-sectional study SETTING: Online survey questionnaire PATIENT(S): A total of 440 female participants who were trying to conceive (TTC) in the past year or currently are TTC. INTERVENTION(S): No interventions administered. MAIN OUTCOME MEASURE(S): Change in fertility preference RESULT(S): Approximately 1 in 3 participants reported changing their fertility preferences because of the COVID-19 pandemic. Of those that reported changing their fertility preferences, 23.9% reported TTC earlier and 61.6% reported TTC later. Preliminary findings show the odds of changing fertility preferences in black or African American women were 5.45 (95% confidence interval [CI], 1.50-19.90) times that of white women and in nonheterosexual women were 2.76 (95% CI, 1.41-5.42) times that of heterosexual women. Furthermore, every 1 unit increase in state anxiety and depressive symptoms was associated with a 26% (95% CI, 3%-54%) or 17% (95% CI, 5%-31%) increase in odds of pushing back TTC, respectively. CONCLUSION(S): This exploratory study highlights how the fertility preferences of racial and ethnic minorities, sexual minorities, and those experiencing mental health issues may be disparately influenced by the pandemic. Research is needed to examine further the disparate effect of the COVID-19 pandemic on fertility preferences.

Theory of mind processing in expectant fathers: Associations with prenatal oxytocin and parental attunement.

Social cognition may facilitate fathers' sensitive caregiving behavior. We administered the Why-How Task, an fMRI task that elicits theory of mind processing, to expectant fathers (n = 39) who also visited the laboratory during their partner's pregnancy and provided a plasma sample for oxytocin assay. Three months postpartum, fathers reported their beliefs about parenting. When rating "Why" an action was being performed versus "How" the action was being performed (Why > How contrast), participants showed activation in regions theorized to support theory of mind, including the dorsomedial prefrontal cortex and superior temporal sulcus. Fathers' prenatal oxytocin levels predicted greater signal change during the Why > How contrast in the inferior parietal lobule. Both prenatal oxytocin and attunement parenting beliefs were associated with Why > How activation in the dorsolateral prefrontal cortex, a theory of mind region implicated in emotion regulation. Posterior parahippocampal gyrus and dorsolateral prefrontal cortex activation during the Why > How contrast predicted fathers' attunement parenting beliefs. In conclusion, fathers' neural activation when engaging in a theory of mind task was associated with their prenatal oxytocin levels and their postpartum attunement parenting beliefs. Results suggest biological and cognitive components of fathering may track with the theory of mind processing.

Physiological linkage in pregnancy: Couples' cortisol, negative conflict behavior, and postpartum depression.

Within-couple concordance in momentary cortisol levels ("cortisol linkage") may reflect meaningful relationship dynamics. In this study, we examined couple cortisol linkage during pregnancy, associations with negative conflict couple behavior, and subsequent postpartum depressive symptoms. Eighty-two opposite-sex couples expecting their first child engaged in a conflict discussion, provided six salivary cortisol samples over the course of a laboratory visit, and then reported on depressive symptoms six months after their baby's birth. Couples' cortisol levels were significantly positively associated with each other, indicating linkage. When mothers and fathers behaved less negatively during the prenatal conflict discussion, they exhibited stronger couple cortisol linkage. Stronger cortisol linkage also predicted fewer postpartum depressive symptoms for fathers. Negative conflict behavior did not moderate the association between cortisol linkage and postpartum depression. These findings suggest that stronger physiological associations between partners during pregnancy may reflect healthier relationship interactions and be beneficial to fathers' postpartum mental health.

Changes in functional connectivity with cognitive behavioral therapy for social anxiety disorder predict outcomes at follow-up.

Approximately half of individuals with Social Anxiety Disorder (SAD) treated with psychological intervention do not achieve clinically significant improvement or retain long-term gains. Neurobiological models of SAD propose that disruptions in functioning of amygdala-prefrontal circuitry is implicated in short-term treatment response. However, whether treatment-related changes in functional connectivity predict long-term well-being after psychotherapy is unknown. Patients with SAD completed an incidental emotion regulation task during fMRI before and after treatment with cognitive behavioral therapy or acceptance and commitment therapy (n = 23, collapsed across groups). Psychophysiological interaction analyses using amygdala seed regions were conducted to assess changes in functional connectivity from pre-to post-treatment that predicted symptom change from 6 to 12-month follow-up. Negative change (i.e., greater inverse/weaker positive) in amygdala connectivity with the dorsomedial prefrontal cortex (dmPFC) and dorsal anterior cingulate cortex (dACC) predicted greater symptom reduction during follow-up. Positive change in amygdala connectivity with the cerebellum, fusiform gyrus, and pre-central and post-central gyri predicted less symptom reduction (e.g., no change or worsening). Results suggest that strengthened amygdala connectivity with regulatory regions may promote better long-term outcomes, whereas changes with visual and sensorimotor regions may represent sensitization to emotion-related cues, conferring poorer outcomes. Clinical implications for treatment personalization are discussed, should effects replicate in larger samples.

Prenatal relationship conflict behavior predicts childbirth experiences and birth outcomes.

Despite evidence linking prenatal psychosocial stress and social support to perinatal maternal and infant health, no study has explored couple conflict behavior during pregnancy as a predictor of subsequent birth outcomes. The current study examines whether couples' positive and negative conflict behaviors during pregnancy predict their stress during the birth experience and gestational and birth outcomes. Forty-seven first-time expectant couples participated in a conflict discussion during pregnancy that was observationally coded. Several months later, following the birth of their child, couples reported on their subjective childbirth stress. By summing medical chart data on gestational outcomes and birth complications, we computed a cumulative birth risk score. Negative conflict behavior was related to higher cumulative birth risk scores, and conversely, positive conflict behavior was associated with lower birth risk, even after controlling for maternal pregnancy symptoms. Similarly, more negative conflict behavior predicted higher mother-reported birth stress, while positive conflict behavior predicted lower father-reported birth stress. However, birth stress effects became nonsignificant after controlling for maternal pregnancy symptoms. Although the pregnancy literature has focused primarily on maternal characteristics, these findings highlight the significance of couple interactions in predicting parental birth stress and birth outcomes. This study integrates psychological, behavioral, and medical chart data to enhance our understanding of how interpersonal factors influence gestational outcomes and the birth experience. These results have important clinical implications for potential couple interventions during pregnancy that can shape fetal development, the labor and delivery experience, and influence child and family health. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Social Allostasis and Social Allostatic Load: A New Model for Research in Social Dynamics, Stress, and Health.

Theories such as social baseline theory have argued that social groups serve a regulatory function but have not explored whether this regulatory process carries costs for the group. Allostatic load, the wear and tear on regulatory systems caused by chronic or frequent stress, is marked by diminished stress system flexibility and compromised recovery. We argue that allostatic load may develop within social groups as well and provide a model for how relationship dysfunction operates. Social allostatic load may be characterized by processes such as groups becoming locked into static patterns of interaction and may ultimately lead to up-regulation or down-regulation of a group's set point, or the optimal range of arousal or affect around which the group tends to converge. Many studies of emotional and physiological linkage within groups have reported that highly correlated states of arousal, which may reflect failure to maintain a group-level regulatory baseline, occur in the context of stress, conflict, and relationship distress. Relationship strain may also place greater demands on neurocognitive regulatory processes. Just as allostatic load may be detrimental to individual health, social allostatic load may corrode relationship quality.

Examining Positive and Negative Affect as Outcomes and Moderators of Cognitive-Behavioral Therapy and Acceptance and Commitment Therapy for Social Anxiety Disorder.

Traditional cognitive-behavioral therapy (CBT) for anxiety disorders has been designed to target reductions in negative affect (NA) associated with defense-related processes. However, a subset of anxiety disorders, including social anxiety disorder (SAD), are also characterized by low positive affect (PA) resulting from separate deficits in appetitive-related processes. In contrast to CBT, "third-wave" approaches, such as acceptance and commitment therapy (ACT), align more consistently with motivational processes and, as a result, PA. However, the differential effect of CBT and ACT on PA and NA has yet to be investigated. Using secondary data from a randomized controlled trial, the present study sought to compare CBT's (n = 45) and ACT's (n = 35) effect on PA and NA in SAD. Findings were compared to a wait-list (WL) control condition (n = 31), as well as normative data from a general adult sample. Baseline PA and NA were also examined as moderators and predictors of theory-relevant treatment outcomes. NA decreased significantly in both CBT and ACT from pre to posttreatment. Although ACT outperformed WL in reducing NA, this effect was not observed for CBT. PA increased significantly in both CBT and ACT from pre to posttreatment, with neither ACT nor CBT outperforming WL in increasing PA. Neither PA nor NA were found to moderate theoretically relevant treatment outcomes. Findings suggest that ACT and CBT share common treatment mechanisms, making them more similar than distinct. Further efforts should be focused on optimizing CBT's and ACT's influence on threat and reward learning, and elucidating common processes of change.