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Research examining the purported association between violent gaming and aggression remains controversial due to concerns related to methodology, unclear neurocognitive mechanisms, and the failure to adequately consider the role of individual differences in susceptibility. To help address these concerns, we used fMRI and an emotional empathy task to examine whether acute and cumulative violent gaming exposure were associated with abnormalities in emotional empathy as a function of trait-empathy. Emotional empathy was targeted given its involvement in regulating not only aggression, but also other important social functions such as compassion and prosocial behaviour. We hypothesized that violent gaming exposure increases the risk of aberrant social behaviour by altering the aversive value of distress cues. Contrary to expectations, neither behavioural ratings nor empathy-related brain activity varied as a function of violent gaming exposure. Notably, however, activation patterns in somatosensory and motor cortices reflected an interaction between violent gaming exposure and trait empathy. Thus, our results are inconsistent with a straightforward relationship between violent gaming exposure and reduced empathy. Furthermore, they highlight the importance of considering both individual differences in susceptibility and other aspects of cognition related to social functioning to best inform public concern regarding safe gaming practices.
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Empatía , Imagen por Resonancia Magnética , Juegos de Video , Humanos , Empatía/fisiología , Juegos de Video/psicología , Masculino , Imagen por Resonancia Magnética/métodos , Adulto Joven , Adulto , Encéfalo/fisiología , Encéfalo/diagnóstico por imagen , Femenino , Adolescente , Violencia/psicología , Mapeo Encefálico/métodos , Agresión/fisiología , Agresión/psicología , Emociones/fisiología , Exposición a la Violencia/psicología , Cognición/fisiologíaRESUMEN
Introduction: Real-time fMRI-based neurofeedback (rt-fMRI-NFB) is a non-invasive technology that enables individuals to self-regulate brain activity linked to neuropsychiatric symptoms, including those associated with post-traumatic stress disorder (PTSD). Selecting the target brain region for neurofeedback-mediated regulation is primarily informed by the neurobiological characteristics of the participant population. There is a strong link between PTSD symptoms and multiple functional disruptions in the brain, including hyperactivity within both the amygdala and posterior cingulate cortex (PCC) during trauma-related processing. As such, previous rt-fMRI-NFB studies have focused on these two target regions when training individuals with PTSD to regulate neural activity. However, the differential effects of neurofeedback target selection on PTSD-related neural activity and clinical outcomes have not previously been investigated. Methods: Here, we compared whole-brain activation and changes in PTSD symptoms between PTSD participants (n = 28) that trained to downregulate activity within either the amygdala (n = 14) or the PCC (n = 14) while viewing personalized trauma words. Results: For the PCC as compared to the amygdala group, we observed decreased neural activity in several regions implicated in PTSD psychopathology - namely, the bilateral cuneus/precuneus/primary visual cortex, the left superior parietal lobule, the left occipital pole, and the right superior temporal gyrus/temporoparietal junction (TPJ) - during target region downregulation using rt-fMRI-NFB. Conversely, for the amygdala as compared to the PCC group, there were no unique (i.e., over and above that of the PCC group) decreases in neural activity. Importantly, amygdala downregulation was not associated with significantly improved PTSD symptoms, whereas PCC downregulation was associated with reduced reliving and distress symptoms over the course of this single training session. In this pilot analysis, we did not detect significant between-group differences in state PTSD symptoms during neurofeedback. As a critical control, the PCC and amygdala groups did not differ in their ability to downregulate activity within their respective target brain regions. This indicates that subsequent whole-brain neural activation results can be attributed to the effects of the neurofeedback target region selection in terms of neurophysiological function, rather than as a result of group differences in regulatory success. Conclusion: In this study, neurofeedback-mediated downregulation of the PCC was differentially associated with reduced state PTSD symptoms and simultaneous decreases in PTSD-associated brain activity during a single training session. This novel analysis may guide researchers in choosing a neurofeedback target region in future rt-fMRI-NFB studies and help to establish the clinical efficacy of specific neurofeedback targets for PTSD. A future multi-session clinical trial of rt-fMRI-NFB that directly compares between PCC and amygdala target regions is warranted.
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Stress generation theory initially posited that depression elevates risk for some stressful events (i.e., dependent events) but not others (i.e., independent events). This preregistered meta-analytic review examined whether stress generation occurs transdiagnostically by examining 95 longitudinal studies with 38,228 participants (537 total effect sizes) from over 30 years of research. Our multilevel meta-analyses found evidence of stress generation across a broad range of psychopathology, as evidenced by significantly larger prospective effects for dependent (overall psychopathology: r = .23) than independent (overall psychopathology: r = .10) stress. We also identified unique patterns of effects across specific types of psychopathology. For example, effects were larger for depression than anxiety. Furthermore, effects were sometimes larger in studies with younger participants, shorter time lags between assessments, checklist measures of stress, and for interpersonal stressors. Finally, a multilevel meta-analytic structural equation model suggested that dependent stress exacerbates psychopathology symptoms over time (ß = .04), possibly contributing to chronicity. Interventions targeting the prevention of stress generation may mitigate chronic psychopathology. Conclusions of this study are limited by the predominance of depression effect sizes in the literature and our review of only English language articles. On the other hand, the findings are strengthened by rigorous inclusion criteria, lack of publication bias, and absence of moderating effects by publication year. The latter underscores the replicability of the stress generation effect over the last 30 years. Taken together, the review provides robust evidence that stress generation is a cross-diagnostic phenomenon that contributes to a vicious cycle of increasing stress and psychopathology. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
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Trastornos de Ansiedad , Ansiedad , HumanosRESUMEN
Collective research has identified a key electroencephalogram signature in patients with post-traumatic stress disorder, consisting of abnormally reduced alpha (8-12â Hz) rhythms. We conducted a 20-session, double-blind, randomized controlled trial of alpha desynchronizing neurofeedback in patients with post-traumatic stress disorder over 20 weeks. Our objective was to provide mechanistic evidence underlying potential clinical improvements by examining changes in aberrant post-traumatic stress disorder brain rhythms (namely, alpha oscillations) as a function of neurofeedback treatment. We randomly assigned participants with a primary diagnosis of post-traumatic stress disorder (n = 38) to either an experimental group (n = 20) or a sham-control group (n = 18). A multichannel electroencephalogram cap was used to record whole-scalp resting-state activity pre- and post-neurofeedback treatment, for both the experimental and sham-control post-traumatic stress disorder groups. We first observed significantly reduced relative alpha source power at baseline in patients with post-traumatic stress disorder as compared to an age/sex-matched group of neurotypical healthy controls (n = 32), primarily within regions of the anterior default mode network. Post-treatment, we found that only post-traumatic stress disorder patients in the experimental neurofeedback group demonstrated significant alpha resynchronization within areas that displayed abnormally low alpha power at baseline. In parallel, we observed significantly decreased post-traumatic stress disorder severity scores in the experimental neurofeedback group only, when comparing baseline to post-treatment (Cohen's d = 0.77) and three-month follow-up scores (Cohen's d = 0.75), with a remission rate of 60.0% at the three-month follow-up. Overall, our results indicate that neurofeedback training can rescue pathologically reduced alpha rhythmicity, a functional biomarker that has repeatedly been linked to symptoms of hyperarousal and cortical disinhibition in post-traumatic stress disorder. This randomized controlled trial provides long-term evidence suggesting that the 'alpha rebound effect' (i.e. homeostatic alpha resynchronization) occurs within key regions of the default mode network previously implicated in post-traumatic stress disorder.
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BACKGROUND: Alterations within large-scale brain networks-namely, the default mode (DMN) and salience networks (SN)-are present among individuals with posttraumatic stress disorder (PTSD). Previous real-time functional magnetic resonance imaging (fMRI) and electroencephalography neurofeedback studies suggest that regulating posterior cingulate cortex (PCC; the primary hub of the posterior DMN) activity may reduce PTSD symptoms and recalibrate altered network dynamics. However, PCC connectivity to the DMN and SN during PCC-targeted fMRI neurofeedback remains unexamined and may help to elucidate neurophysiological mechanisms through which these symptom improvements may occur. METHODS: Using a trauma/emotion provocation paradigm, we investigated psychophysiological interactions over a single session of neurofeedback among PTSD (n = 14) and healthy control (n = 15) participants. We compared PCC functional connectivity between regulate (in which participants downregulated PCC activity) and view (in which participants did not exert regulatory control) conditions across the whole-brain as well as in a priori specified regions-of-interest. RESULTS: During regulate as compared to view conditions, only the PTSD group showed significant PCC connectivity with anterior DMN (dmPFC, vmPFC) and SN (posterior insula) regions, whereas both groups displayed PCC connectivity with other posterior DMN areas (precuneus/cuneus). Additionally, as compared with controls, the PTSD group showed significantly greater PCC connectivity with the SN (amygdala) during regulate as compared to view conditions. Moreover, linear regression analyses revealed that during regulate as compared to view conditions, PCC connectivity to DMN and SN regions was positively correlated to psychiatric symptoms across all participants. CONCLUSION: In summary, observations of PCC connectivity to the DMN and SN provide emerging evidence of neural mechanisms underlying PCC-targeted fMRI neurofeedback among individuals with PTSD. This supports the use of PCC-targeted neurofeedback as a means by which to recalibrate PTSD-associated alterations in neural connectivity within the DMN and SN, which together, may help to facilitate improved emotion regulation abilities in PTSD.
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Neocórtex , Neurorretroalimentación , Trastornos por Estrés Postraumático , Humanos , Trastornos por Estrés Postraumático/diagnóstico por imagen , Trastornos por Estrés Postraumático/terapia , Giro del Cíngulo , Neurorretroalimentación/métodos , Imagen por Resonancia Magnética , Red en Modo Predeterminado/patología , Encéfalo , Amígdala del Cerebelo , Mapeo EncefálicoRESUMEN
Historically, empathy has been thought to motivate prosocial behaviour and inhibit aggressive behaviour. Contrary to current assumptions and theoretical support, a meta-analysis revealed a small effect of empathy on aggression among adults (Vachon, Lynam, & Johnson, 2014). The current study sought to determine whether broadening the focus from empathy to include other socially relevant affective characteristics (i.e., callous-unemotional traits) was advantageous in predicting aggressive behaviour. As little is known about the strength of this association among youth, the current study meta-analytically examined 192 unique effect sizes drawn from published and unpublished studies reporting on samples of children and adolescents. Analyses were conducted across general, cognitive, and emotional empathy, as well as callous-unemotional traits, and general, direct, indirect, proactive, and reactive aggression. Significant variability was noted across effect sizes. Consistent with a prior meta-analysis involving adults (Vachon et al., 2014), small to moderate associations were identified between aggression and traditional measures of empathy (i.e., general, emotional, cognitive); these effects ranged from r = -0.06 to -0.26. Among broader measures of emotional style (i.e., callous-unemotional traits), moderate to large effects were found; ranging from r = 0.30 to 0.37. Results suggested that broader affective measures may be more strongly associated with aggression than empathy alone. The results raise questions about the nature of empathy assessment and indicate the utility of targeting multiple emotion-related factors during treatment to effectively reduce aggressive behaviour. In particular, the results underscore of the importance of considering the limited prosocial emotions specifier (perhaps trans-diagnostically given the varied nature of the sample) when considering implications for prognosis and treatment targets.
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Trastorno de la Conducta , Niño , Adulto , Adolescente , Humanos , Trastorno de la Conducta/psicología , Empatía , Agresión/psicología , EmocionesRESUMEN
BACKGROUND: A moral injury occurs when a deeply held moral code has been violated, and it can lead to the development of symptoms of posttraumatic stress disorder (PTSD). However, the neural correlates that differentiate moral injury and PTSD remain largely unknown. Intrinsic connectivity networks such as the default mode network (DMN) appear to be altered in people with PTSD who have experienced moral injury. However, brainstem, midbrain and cerebellar systems are rarely integrated into the intrinsic connectivity networks; this is a critical oversight, because these systems display marked differences in people with PTSD and are thought to underlie strong moral emotions such as shame, guilt and betrayal. METHODS: We conducted an independent component analysis on data generated during script-driven memory recall of moral injury in participants with military- or law enforcement-related PTSD (n = 28), participants with civilian-related PTSD (n = 28) and healthy controls exposed to a potentially morally injurious event (n = 18). We conducted group-wise comparisons of functional network connectivity differences across a DMN-correlated independent component, with a particular focus on brainstem, midbrain and cerebellar systems. RESULTS: We found stronger functional network connectivity in the midbrain periaqueductal grey (t 71 = 4.95, p FDR = 0.028, k = 39) and cerebellar lobule IX (t 71 = 4.44, p FDR = 0.046, k = 49) in participants with civilian-related PTSD as compared to healthy controls. We also found a trend toward stronger functional network connectivity in the midbrain periaqueductal grey (t 71 = 4.22, p FDR = 0.076, k = 60) in participants with military- or law enforcement-related PTSD as compared to healthy controls. LIMITATIONS: The significant clusters were large, but resolution is generally lower for subcortical structures. CONCLUSION: In PTSD, the DMN appears to be biased toward lower-level, midbrain systems, which may drive toxic shame and related moral emotions that are common in PTSD, highlighting the depth at which moral injuries are represented neurobiologically.
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Trastornos por Estrés Postraumático , Encéfalo/diagnóstico por imagen , Red en Modo Predeterminado , Humanos , Imagen por Resonancia Magnética , Mesencéfalo/diagnóstico por imagen , Principios Morales , Trastornos por Estrés Postraumático/diagnóstico por imagenRESUMEN
BACKGROUND: Intrinsic connectivity networks, including the default mode network (DMN), are frequently disrupted in individuals with posttraumatic stress disorder (PTSD). The posterior cingulate cortex (PCC) is the main hub of the posterior DMN, where the therapeutic regulation of this region with real-time fMRI neurofeedback (NFB) has yet to be explored. METHODS: We investigated PCC downregulation while processing trauma/stressful words over 3 NFB training runs and a transfer run without NFB (total n = 29, PTSD n = 14, healthy controls n = 15). We also examined the predictive accuracy of machine learning models in classifying PTSD versus healthy controls during NFB training. RESULTS: Both the PTSD and healthy control groups demonstrated reduced reliving symptoms in response to trauma/stressful stimuli, where the PTSD group additionally showed reduced symptoms of distress. We found that both groups were able to downregulate the PCC with similar success over NFB training and in the transfer run, although downregulation was associated with unique within-group decreases in activation within the bilateral dmPFC, bilateral postcentral gyrus, right amygdala/hippocampus, cingulate cortex, and bilateral temporal pole/gyri. By contrast, downregulation was associated with increased activation in the right dlPFC among healthy controls as compared to PTSD. During PCC downregulation, right dlPFC activation was negatively correlated to PTSD symptom severity scores and difficulties in emotion regulation. Finally, machine learning algorithms were able to classify PTSD versus healthy participants based on brain activation during NFB training with 80% accuracy. CONCLUSIONS: This is the first study to investigate PCC downregulation with real-time fMRI NFB in both PTSD and healthy controls. Our results reveal acute decreases in symptoms over training and provide converging evidence for EEG-NFB targeting brain networks linked to the PCC.
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Neurorretroalimentación , Trastornos por Estrés Postraumático , Regulación hacia Abajo , Giro del Cíngulo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Trastornos por Estrés Postraumático/diagnóstico por imagen , Trastornos por Estrés Postraumático/terapiaRESUMEN
BACKGROUND: Posttraumatic stress disorder (PTSD) is associated with markers of accelerated aging. Estimates of brain age, compared to chronological age, may clarify the effects of PTSD on the brain and may inform treatment approaches targeting the neurobiology of aging in the context of PTSD. METHOD: Adult subjects (N = 2229; 56.2% male) aged 18-69 years (mean = 35.6, SD = 11.0) from 21 ENIGMA-PGC PTSD sites underwent T1-weighted brain structural magnetic resonance imaging, and PTSD assessment (PTSD+, n = 884). Previously trained voxel-wise (brainageR) and region-of-interest (BARACUS and PHOTON) machine learning pipelines were compared in a subset of control subjects (n = 386). Linear mixed effects models were conducted in the full sample (those with and without PTSD) to examine the effect of PTSD on brain predicted age difference (brain PAD; brain age - chronological age) controlling for chronological age, sex, and scan site. RESULTS: BrainageR most accurately predicted brain age in a subset (n = 386) of controls (brainageR: ICC = 0.71, R = 0.72, MAE = 5.68; PHOTON: ICC = 0.61, R = 0.62, MAE = 6.37; BARACUS: ICC = 0.47, R = 0.64, MAE = 8.80). Using brainageR, a three-way interaction revealed that young males with PTSD exhibited higher brain PAD relative to male controls in young and old age groups; old males with PTSD exhibited lower brain PAD compared to male controls of all ages. DISCUSSION: Differential impact of PTSD on brain PAD in younger versus older males may indicate a critical window when PTSD impacts brain aging, followed by age-related brain changes that are consonant with individuals without PTSD. Future longitudinal research is warranted to understand how PTSD impacts brain aging across the lifespan.
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Trastornos por Estrés Postraumático , Adolescente , Adulto , Anciano , Envejecimiento , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Femenino , Humanos , Aprendizaje Automático , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Trastornos por Estrés Postraumático/diagnóstico por imagen , Adulto JovenRESUMEN
In people with mental health issues, approximately 20% have co-occurring substance use, often involving cannabis. Although emotion regulation can be affected both by major depressive disorder (MDD) and by cannabis use, the relationship among all three factors is unknown. In this study, we used fMRI to evaluate the effect that cannabis use and MDD have on brain activation during an emotion regulation task. Differences were assessed in 74 emerging adults aged 16-23 with and without MDD who either used or did not use cannabis. Severity of depressive symptoms, emotion regulation style, and age of cannabis use onset were also measured. Both MDD and cannabis use interacted with the emotion regulation task in the left temporal lobe, however the location of the interaction differed for each factor. Specifically, MDD showed an interaction with emotion regulation in the middle temporal gyrus, whereas cannabis use showed an interaction in the superior temporal gyrus. Emotion regulation style predicted activity in the right superior frontal gyrus, however, this did not interact with MDD or cannabis use. Severity of depressive symptoms interacted with the emotion regulation task in the left middle temporal gyrus. The results highlight the influence of cannabis use and MDD on emotion regulation processing, suggesting that both may have a broader impact on the brain than previously thought.
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Cannabis , Trastorno Depresivo Mayor , Regulación Emocional , Adulto , Encéfalo/diagnóstico por imagen , Emociones , Humanos , Imagen por Resonancia MagnéticaRESUMEN
OBJECTIVE: About 20-26% of children and youth with a mental health disorder (depending on age and respondent) report receiving services from a community-based Child and Youth Mental Health (CYMH) agency. However, because agencies have an upper age limit of 18-years old, youth requiring ongoing mental health services must "transition" to adult-oriented care. General healthcare providers (e.g., family physicians) likely provide this care. The objective of this study was to compare the likelihood of receiving physician-based mental health services after age 18 between youth who had received community-based mental health services and a matched population sample. METHOD: A longitudinal matched cohort study was conducted in Ontario, Canada. A CYMH cohort that received mental health care at one of five CYMH agencies, aged 7-14 years at their first visit (N=2,822), was compared to age, sex, region-matched controls (N=8,466). RESULTS: CYMH youth were twice as likely as the comparison sample to have a physician-based mental health visit (i.e., by a family physician, pediatrician, psychiatrists) after age 18; median time to first visit was 3.3 years. Having a physician mental health visit before age 18 was associated with a greater likelihood of experiencing the outcome than community-based CYMH services alone. CONCLUSION: Most youth involved in community-based CYMH agencies will re-access services from physicians as adults. Youth receiving mental health services only within community agencies, and not from physicians, may be less likely to receive physician-based mental health services as adults. Collaboration between CYMH agencies and family physicians may be important for youth who require ongoing care into adulthood.
OBJECTIF: Environ 20 à 26 % des enfants et des adolescents souffrant d'un trouble de santé mentale (dépendant de l'âge et du répondant) déclarent recevoir des services d'un organisme communautaire de santé mentale pour enfants et adolescents (SMEA) Toutefois, puisque les organismes ont une limite d'âge supérieur de 18 ans, les jeunes nécessitant des services de santé mentale doivent faire la « transition ¼ aux soins pour adultes. Les prestataires de soins de santé généraux (p. ex., les médecins de famille) dispensent probablement ces services. La présente étude visait à comparer la probabilité de recevoir des services de santé mentale par un médecin après l'âge de 18 ans entre un jeune qui avait reçu des services de santé mentale et un échantillon apparié dans la population. MÉTHODE: Une étude de cohorte longitudinale appariée a été menée en Ontario, Canada. Une cohorte SMEA qui recevait des soins de santé mentale à l'un des cinq organismes SMEA, âgés entre 7 et 14 ans à leur première visite (N = 2,822), a été comparée pour l'âge, le sexe, les contrôles appariés par région (N = 8,466). RÉSULTATS: Les jeunes des SMEA étaient deux fois plus susceptibles que l'échantillon de comparaison d'avoir une visite de santé mentale par un médecin (c.-à-d. par un pédiatre médecin de famille, des psychiatres) après l'âge de 18 ans le temps moyen avant une première visite était 3,3 ans. Avoir une visite de santé mentale avec un médecin avant l'âge de 18 ans était associé à une plus grande probabilité de connaître le résultat que par les services SMEA communautaires à eux seuls. CONCLUSION: La plupart des jeunes impliqués dans les organismes communautaires SMEA accéderont de nouveau aux services de médecins en tant qu'adulte. Les jeunes recevant des services de santé mentale uniquement d'organismes communautaires et non de médecins peuvent être moins susceptibles de recevoir des services de santé mentale par un médecin en tant qu'adultes. La collaboration entre les organismes SMEA et les médecins de famille peut être importante pour les jeunes qui nécessitent des soins constants à l'âge adulte.
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BACKGROUND: Emotions have been associated with culturally universal and distinct bodily sensation "maps". Despite this knowledge, to date few studies have explored emotion-specific topography along clinically relevant dimensions, such as alexithymia. OBJECTIVE: We aimed to investigate emotion-specific topographies among individuals exposed to childhood maltreatment or neglect with absent (n = 51) or with probable (n = 46) alexithymia in adulthood, as defined by scores on the Toronto Alexithymia Scale (TAS-20). PARTICIPANTS AND SETTING: Ninety eight adult participants with exposure to childhood maltreatment or neglect were recruited to complete an online survey. METHODS: Using the well-validated emBODY tool (Nummenmaa et al., 2014), participants reported on their somatic experience of 17 emotions. RESULTS: Random effects analyses revealed topographically distinct bodily sensation t-maps that differentiated participants who endorsed probable alexithymia from those who did not (p-FDR < .05). Consistent with our a priori hypothesis, the probable alexithymia group reported a muted, diffuse and undifferentiated pattern of emotion-specific bodily sensation, whereas the non-alexithymia group reported a more distinct and localized pattern. CONCLUSIONS: These results suggest that difficulty identifying and labeling emotions, as observed in alexithymia, may arise, in part, from an altered perception of somatic activation. It is well-established that childhood maltreatment predicts the development of alexithymia symptoms. The preliminary findings presented here expand our working understanding of the physical markers of childhood trauma, which may be used in practice to aid detection and to monitor treatment outcomes.
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Síntomas Afectivos , Emociones , Adulto , Humanos , Encuestas y CuestionariosRESUMEN
A growing number of studies have examined alterations in white matter organization in people with posttraumatic stress disorder (PTSD) using diffusion MRI (dMRI), but the results have been mixed which may be partially due to relatively small sample sizes among studies. Altered structural connectivity may be both a neurobiological vulnerability for, and a result of, PTSD. In an effort to find reliable effects, we present a multi-cohort analysis of dMRI metrics across 3047 individuals from 28 cohorts currently participating in the PGC-ENIGMA PTSD working group (a joint partnership between the Psychiatric Genomics Consortium and the Enhancing NeuroImaging Genetics through Meta-Analysis consortium). Comparing regional white matter metrics across the full brain in 1426 individuals with PTSD and 1621 controls (2174 males/873 females) between ages 18-83, 92% of whom were trauma-exposed, we report associations between PTSD and disrupted white matter organization measured by lower fractional anisotropy (FA) in the tapetum region of the corpus callosum (Cohen's d = -0.11, p = 0.0055). The tapetum connects the left and right hippocampus, for which structure and function have been consistently implicated in PTSD. Results were consistent even after accounting for the effects of multiple potentially confounding variables: childhood trauma exposure, comorbid depression, history of traumatic brain injury, current alcohol abuse or dependence, and current use of psychotropic medications. Our results show that PTSD may be associated with alterations in the broader hippocampal network.
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Trastornos por Estrés Postraumático , Sustancia Blanca , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anisotropía , Encéfalo/diagnóstico por imagen , Imagen de Difusión Tensora , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos por Estrés Postraumático/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen , Adulto JovenRESUMEN
BACKGROUND: Moral injury (MI) is consistently associated with adverse mental health outcomes, including the development of posttraumatic stress disorder (PTSD) and suicidality. METHODS: We investigated neural activation patterns associated with MI event recall using functional magnetic resonance imaging in participants with military and public safety-related PTSD, relative to civilian MI-exposed controls. RESULTS: MI recall in the PTSD as compared to control group was associated with increased neural activation among salience network nodes involved in viscerosensory processing and hyperarousal (right posterior insula, dorsal anterior cingulate cortex; dACC), regions involved in defensive responding (left postcentral gyrus), and areas responsible for top-down cognitive control of emotions (left dorsolateral prefrontal cortex; dlPFC). Within the PTSD group, measures of state and trait shame correlated negatively with activity among default mode network regions associated with self-related processing and moral cognition (dorsomedial prefrontal cortex; dmPFC) and salience network regions associated with viscerosensory processing (left posterior insula), respectively. CONCLUSIONS: These findings suggest that MI event processing is altered in military and public safety-related PTSD, relative to MI-exposed controls. Here, it appears probable that as individuals with PTSD recall their MI event, they experience a surge of blame-related processing of bodily sensations within salience network regions, including the right posterior insula and the dACC, which in turn, prompt regulatory strategies at the level of the left dlPFC aimed at increasing cognitive control and inhibiting emotional affect. These results are consistent with previous findings showing enhanced sensory processing and altered top-down control in PTSD samples during autobiographical memory recall.
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Trastornos por Estrés Postraumático , Encéfalo/diagnóstico por imagen , Emociones , Humanos , Imagen por Resonancia Magnética , Recuerdo Mental , Vergüenza , Trastornos por Estrés Postraumático/diagnóstico por imagenRESUMEN
Intrinsic connectivity networks (ICNs), including the default mode network (DMN), the central executive network (CEN), and the salience network (SN) have been shown to be aberrant in patients with posttraumatic stress disorder (PTSD). The purpose of the current study was to a) compare ICN functional connectivity between PTSD, dissociative subtype PTSD (PTSD+DS) and healthy individuals; and b) to examine the use of multivariate machine learning algorithms in classifying PTSD, PTSD+DS, and healthy individuals based on ICN functional activation. Our neuroimaging dataset consisted of resting-state fMRI scans from 186 participants [PTSD (n = 81); PTSD + DS (n = 49); and healthy controls (n = 56)]. We performed group-level independent component analyses to evaluate functional connectivity differences within each ICN. Multiclass Gaussian Process Classification algorithms within PRoNTo software were then used to predict the diagnosis of PTSD, PTSD+DS, and healthy individuals based on ICN functional activation. When comparing the functional connectivity of ICNs between PTSD, PTSD+DS and healthy controls, we found differential patterns of connectivity to brain regions involved in emotion regulation, in addition to limbic structures and areas involved in self-referential processing, interoception, bodily self-consciousness, and depersonalization/derealization. Machine learning algorithms were able to predict with high accuracy the classification of PTSD, PTSD+DS, and healthy individuals based on ICN functional activation. Our results suggest that alterations within intrinsic connectivity networks may underlie unique psychopathology and symptom presentation among PTSD subtypes. Furthermore, the current findings substantiate the use of machine learning algorithms for classifying subtypes of PTSD illness based on ICNs.
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Trastornos Disociativos/fisiopatología , Emociones/fisiología , Aprendizaje Automático , Vías Nerviosas/fisiopatología , Trastornos por Estrés Postraumático/fisiopatología , Adulto , Amígdala del Cerebelo/fisiopatología , Encéfalo/fisiopatología , Mapeo Encefálico/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Red Nerviosa/fisiopatologíaRESUMEN
OBJECTIVE: The default-mode network (DMN) and salience network (SN) have been shown to display altered connectivity in posttraumatic stress disorder (PTSD). Restoring aberrant connectivity within these networks with electroencephalogram neurofeedback (EEG-NFB) has been shown previously to be associated with acute decreases in symptoms. Here, we conducted a double-blind, sham-controlled randomized trial of alpha-rhythm EEG-NFB in participants with PTSD (n = 36) over 20-weeks. Our aim was to provide mechanistic evidence underlying clinical improvements by examining changes in network connectivity via fMRI. METHODS: We randomly assigned participants with a primary diagnosis of PTSD to either the experimental group (n = 18) or sham-control group (n = 18). We collected resting-state fMRI scans pre- and post-NFB intervention, for both the experimental and sham-control PTSD groups. We further compared baseline brain connectivity measures pre-NFB to age-matched healthy controls (n = 36). RESULTS: With regard to the primary outcome measure of PTSD severity, we found a significant main effect of time in the absence of a group × time interaction. Nevertheless, we found significantly decreased PTSD severity scores in the experimental NFB group only, when comparing post-NFB (dz = 0.71) and 3-month follow-up scores (dz = 0.77) to baseline measures. Interestingly, we found evidence to suggest a shift towards normalization of DMN and SN connectivity post-NFB in the experimental group only. Both decreases in PTSD severity and NFB performance were correlated to DMN and SN connectivity post-NFB in the experimental group. Critically, remission rates of PTSD were significant higher in the experimental group (61.1%) as compared to the sham-control group (33.3%). CONCLUSION: The current study shows mechanistic evidence for therapeutic changes in DMN and SN connectivity that are known to be associated with PTSD psychopathology with no patient dropouts. This preliminary investigation merits further research to demonstrate fully the clinical efficacy of EEG-NFB as an adjunctive therapy for PTSD.
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Neurorretroalimentación , Trastornos por Estrés Postraumático , Encéfalo , Electroencefalografía , Humanos , Imagen por Resonancia Magnética , Trastornos por Estrés Postraumático/diagnóstico por imagen , Trastornos por Estrés Postraumático/terapiaRESUMEN
Individuals with post-traumatic stress disorder (PTSD) typically experience states of reliving and hypervigilance; however, the dissociative subtype of PTSD (PTSD+DS) presents with additional symptoms of depersonalization and derealization. Although the insula is critical to emotion processing, its association with these contrasting symptom profiles is yet to be fully delineated. Accordingly, we investigated insula subregion resting-state functional connectivity patterns among individuals with PTSD, PTSD+DS, and healthy controls. Using SPM12 and PRONTO software, we implemented a seed-based resting-state functional connectivity approach, along with multiclass Gaussian process classification machine learning, respectively, in order to evaluate unique patterns and the predictive validity of insula subregion connectivity among individuals with PTSD (n = 84), PTSD+DS (n = 49), and age-matched healthy controls (n = 51). As compared to PTSD and PTSD+DS, healthy controls showed increased right anterior and posterior insula connectivity with frontal lobe structures. By contrast, PTSD showed increased bilateral posterior insula connectivity with subcortical structures, including the periaqueductal gray. Strikingly, as compared to PTSD and controls, PTSD+DS showed increased bilateral anterior and posterior insula connectivity with posterior cortices, including the left lingual gyrus and the left precuneus. Moreover, machine learning analyses were able to classify PTSD, PTSD+DS, and controls using insula subregion connectivity patterns with 80.4% balanced accuracy (p < .01). These findings suggest a neurobiological distinction between PTSD and its dissociative subtype with regard to insula subregion functional connectivity patterns. Furthermore, machine learning algorithms were able to utilize insula resting-state connectivity patterns to discriminate between participant groups with high predictive accuracy.
Asunto(s)
Corteza Cerebral/fisiopatología , Conectoma/normas , Despersonalización/fisiopatología , Trastornos Disociativos/fisiopatología , Aprendizaje Automático , Trastornos por Estrés Postraumático/fisiopatología , Adulto , Corteza Cerebral/diagnóstico por imagen , Despersonalización/diagnóstico por imagen , Despersonalización/etiología , Trastornos Disociativos/diagnóstico por imagen , Trastornos Disociativos/etiología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Trastornos por Estrés Postraumático/complicaciones , Trastornos por Estrés Postraumático/diagnóstico por imagenRESUMEN
BACKGROUND: Some children with mental health (MH) problems have been found to receive ongoing care, either continuously or episodically. We sought to replicate patterns of MH service use over extended time periods, and test predictors of these patterns. METHODS: Latent class analyses were applied to 4 years of visit data from five MH agencies and nearly 6000 children, 4- to 13-years-old at their first visit. RESULTS: Five patterns of service use were identified, replicating previous findings. Overall, 14% of cases had two or more episodes of care and 23% were involved for more than 2 years. Most children (53%) were seen for just a few visits within a few months. Two patterns represented cases with two or more episodes of care spanning multiple years. In the two remaining patterns, children tended to have just one episode of care, but the number of sessions and length of involvement varied. Using discriminant function analyses, we were able to predict with just over 50% accuracy children's pattern of service use. Severe externalizing behaviors, high impairment, and high family burden predicted service use patterns with long durations of involvement and frequent visits. CONCLUSIONS: Optimal treatment approaches for children seen for repeated episodes of care or for care lasting multiple years need to be developed. Children with the highest level of need (severe pathology, impairment, and burden) are probably best served by providing high intensity services at the start of care.
Asunto(s)
Servicios de Salud del Niño/estadística & datos numéricos , Utilización de Instalaciones y Servicios/estadística & datos numéricos , Trastornos Mentales/terapia , Servicios de Salud Mental/estadística & datos numéricos , Adolescente , Niño , Preescolar , Femenino , Humanos , MasculinoRESUMEN
BACKGROUND: The field of psychiatry would benefit significantly from developing objective biomarkers that could facilitate the early identification of heterogeneous subtypes of illness. Critically, although machine learning pattern recognition methods have been applied recently to predict many psychiatric disorders, these techniques have not been utilized to predict subtypes of posttraumatic stress disorder (PTSD), including the dissociative subtype of PTSD (PTSD + DS). METHODS: Using Multiclass Gaussian Process Classification within PRoNTo, we examined the classification accuracy of: (i) the mean amplitude of low-frequency fluctuations (mALFF; reflecting spontaneous neural activity during rest); and (ii) seed-based amygdala complex functional connectivity within 181 participants [PTSD (n = 81); PTSD + DS (n = 49); and age-matched healthy trauma-unexposed controls (n = 51)]. We also computed mass-univariate analyses in order to observe regional group differences [false-discovery-rate (FDR)-cluster corrected p < 0.05, k = 20]. RESULTS: We found that extracted features could predict accurately the classification of PTSD, PTSD + DS, and healthy controls, using both resting-state mALFF (91.63% balanced accuracy, p < 0.001) and amygdala complex connectivity maps (85.00% balanced accuracy, p < 0.001). These results were replicated using independent machine learning algorithms/cross-validation procedures. Moreover, areas weighted as being most important for group classification also displayed significant group differences at the univariate level. Here, whereas the PTSD + DS group displayed increased activation within emotion regulation regions, the PTSD group showed increased activation within the amygdala, globus pallidus, and motor/somatosensory regions. CONCLUSION: The current study has significant implications for advancing machine learning applications within the field of psychiatry, as well as for developing objective biomarkers indicative of diagnostic heterogeneity.
Asunto(s)
Amígdala del Cerebelo/diagnóstico por imagen , Trastornos Disociativos/diagnóstico por imagen , Aprendizaje Automático , Trastornos por Estrés Postraumático/diagnóstico por imagen , Adulto , Amígdala del Cerebelo/fisiopatología , Mapeo Encefálico/métodos , Estudios de Casos y Controles , Trastornos Disociativos/fisiopatología , Emociones , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Análisis Multivariante , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiopatología , Descanso , Trastornos por Estrés Postraumático/fisiopatología , Trastornos por Estrés Postraumático/psicología , Adulto JovenRESUMEN
In this article we study the application of nonlinear indices (sometimes called complexity indices) to univariate time series data arising from studies of schizophrenia and bipolar disorder. Specifically, we consider time series arising from EEG studies, ECG studies, and self-report mood data. As part of our analysis, we empirically examine the claim in the literature that complexity tends to be higher in the EEG of schizophrenia patients than controls and that this tendency is dampened or even inverted by medication, increasing age, and reduced symptomatology. Our conclusion is that this claim is only partially supported and propose that symptomatology, specifically the presence or absence of schizophrenia 'deficit syndrome,' may be the most important factor. Results are more consistent in ECG studies in which reduced heart rate complexity is observed in both schizophrenia and bipolar disorder. The applications of nonlinear indices to the effects of antipsychotic medication and the discrimination of mood states are also examined. It is concluded that the monitoring of nonlinear indices may be useful in predicting response to medication and predicting onset of specific mood states.