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1.
Proc Natl Acad Sci U S A ; 121(35): e2406005121, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39172786

RESUMO

Dynamic brain immune function in individuals with posttraumatic stress disorder is rarely studied, despite evidence of peripheral immune dysfunction. Positron emission tomography brain imaging using the radiotracer [11C]PBR28 was used to measure the 18-kDa translocator protein (TSPO), a microglial marker, at baseline and 3 h after administration of lipopolysaccharide (LPS), a potent immune activator. Data were acquired in 15 individuals with PTSD and 15 age-matched controls. The PTSD group exhibited a significantly lower magnitude LPS-induced increase in TSPO availability in an a priori prefrontal-limbic circuit compared to controls. Greater anhedonic symptoms in the PTSD group were associated with a more suppressed neuroimmune response. In addition, while a reduced granulocyte-macrophage colony-stimulating factor response to LPS was observed in the PTSD group, other measured cytokine responses and self-reported sickness symptoms did not differ between groups; these findings highlight group differences in central-peripheral immune system relationships. The results of this study provide evidence of a suppressed microglia-mediated neuroimmune response to a direct immune system insult in individuals with PTSD that is associated with the severity of symptoms. They also provide further support to an emerging literature challenging traditional concepts of microglial and immune function in psychiatric disease.


Assuntos
Anedonia , Microglia , Tomografia por Emissão de Pósitrons , Receptores de GABA , Transtornos de Estresse Pós-Traumáticos , Transtornos de Estresse Pós-Traumáticos/imunologia , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/metabolismo , Humanos , Microglia/imunologia , Microglia/metabolismo , Masculino , Adulto , Tomografia por Emissão de Pósitrons/métodos , Feminino , Receptores de GABA/metabolismo , Lipopolissacarídeos , Pessoa de Meia-Idade , Neuroimunomodulação/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/imunologia , Encéfalo/metabolismo
2.
Proc Natl Acad Sci U S A ; 121(13): e2316841121, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38502706

RESUMO

We show that nocturnal aversive stimuli presented to mice while they are eating and drinking outside of their safe nest can entrain circadian behaviors, leading to a shift toward daytime activity. We also show that the canonical molecular circadian clock is necessary for fear entrainment and that an intact molecular clockwork in the suprachiasmatic nucleus, the site of the central circadian pacemaker, is necessary but not sufficient to sustain fear entrainment of circadian rhythms. Our results demonstrate that entrainment of a circadian clock by cyclic fearful stimuli can lead to severely mistimed circadian behavior that persists even after the aversive stimulus is removed. Together, our findings support the interpretation that circadian and sleep symptoms associated with fear and anxiety disorders are, in part, the output of a fear-entrained clock, and provide a mechanistic insight into this clock.


Assuntos
Relógios Circadianos , Camundongos , Animais , Relógios Circadianos/genética , Núcleo Supraquiasmático , Ritmo Circadiano , Medo
3.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-37991275

RESUMO

Neuroimage studies have reported functional connectome abnormalities in posttraumatic stress disorder (PTSD), especially in adults. However, these studies often treated the brain as a static network, and time-variance of connectome topology in pediatric posttraumatic stress disorder remain unclear. To explore case-control differences in dynamic connectome topology, resting-state functional magnetic resonance imaging data were acquired from 24 treatment-naïve non-comorbid pediatric posttraumatic stress disorder patients and 24 demographically matched trauma-exposed non-posttraumatic stress disorder controls. A graph-theoretic analysis was applied to construct time-varying modular structure of whole-brain networks by maximizing the multilayer modularity. Network switching rate at the global, subnetwork, and nodal levels were calculated and compared between posttraumatic stress disorder and trauma-exposed non-posttraumatic stress disorder groups, and their associations with posttraumatic stress disorder symptom severity and sex interactions were explored. At the global level, individuals with posttraumatic stress disorder exhibited significantly lower network switching rates compared to trauma-exposed non-posttraumatic stress disorder controls. This difference was mainly involved in default-mode and dorsal attention subnetworks, as well as in inferior temporal and parietal brain nodes. Posttraumatic stress disorder symptom severity was negatively correlated with switching rate in the global network and default mode network. No significant differences were observed in the interaction between diagnosis and sex/age. Pediatric posttraumatic stress disorder is associated with dynamic reconfiguration of brain networks, which may provide insights into the biological basis of this disorder.


Assuntos
Conectoma , Transtornos de Estresse Pós-Traumáticos , Adulto , Humanos , Criança , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Rede Nervosa , Encéfalo , Conectoma/métodos
4.
Cereb Cortex ; 34(5)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38813966

RESUMO

A multitude of factors are associated with the symptoms of post-traumatic stress disorder. However, establishing which predictors are most strongly associated with post-traumatic stress disorder symptoms is complicated because few studies are able to consider multiple factors simultaneously across the biopsychosocial domains that are implicated by existing theoretical models. Further, post-traumatic stress disorder is heterogeneous, and studies using case-control designs may obscure which factors relate uniquely to symptom dimensions. Here we used Bayesian variable selection to identify the most important predictors for overall post-traumatic stress disorder symptoms and individual symptom dimensions in a community sample of 569 adults (18 to 85 yr of age). Candidate predictors were selected from previously established risk factors relevant for post-traumatic stress disorder and included psychological measures, behavioral measures, and resting state functional connectivity among brain regions. In a follow-up analysis, we compared results controlling for current depression symptoms in order to examine specificity. Poor sleep quality and dimensions of temperament and impulsivity were consistently associated with greater post-traumatic stress disorder symptom severity. In addition to self-report measures, brain functional connectivity among regions commonly ascribed to the default mode network, central executive network, and salience network explained the unique variability of post-traumatic stress disorder symptoms. This study demonstrates the unique contributions of psychological measures and neural substrates to post-traumatic stress disorder symptoms.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/psicologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Adulto , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Encéfalo/fisiopatologia , Encéfalo/diagnóstico por imagem , Idoso de 80 Anos ou mais , Adolescente , Teorema de Bayes , Depressão/psicologia , Depressão/fisiopatologia , Comportamento Impulsivo/fisiologia , Temperamento/fisiologia
5.
Cereb Cortex ; 34(6)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38864573

RESUMO

The experience of an extremely aversive event can produce enduring deleterious behavioral, and neural consequences, among which posttraumatic stress disorder (PTSD) is a representative example. Although adolescence is a period of great exposure to potentially traumatic events, the effects of trauma during adolescence remain understudied in clinical neuroscience. In this exploratory work, we aim to study the whole-cortex functional organization of 14 adolescents with PTSD using a data-driven method tailored to our population of interest. To do so, we built on the network neuroscience framework and specifically on multilayer (multisubject) community analysis to study the functional connectivity of the brain. We show, across different topological scales (the number of communities composing the cortex), a hyper-colocalization between regions belonging to occipital and pericentral regions and hypo-colocalization in middle temporal, posterior-anterior medial, and frontal cortices in the adolescent PTSD group compared to a nontrauma exposed group of adolescents. These preliminary results raise the question of an altered large-scale cortical organization in adolescent PTSD, opening an interesting line of research for future investigations.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/psicologia , Adolescente , Feminino , Masculino , Encéfalo/fisiopatologia , Encéfalo/diagnóstico por imagem , Vias Neurais/fisiopatologia , Mapeamento Encefálico/métodos , Rede Nervosa/fisiopatologia , Rede Nervosa/diagnóstico por imagem , Córtex Cerebral/fisiopatologia , Córtex Cerebral/diagnóstico por imagem
6.
Annu Rev Psychol ; 75: 573-599, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-37566760

RESUMO

Disasters cause sweeping damage, hardship, and loss of life. In this article, we first consider the dominant psychological approach to disasters and its narrow focus on psychopathology (e.g., posttraumatic stress disorder). We then review research on a broader approach that has identified heterogeneous, highly replicable trajectories of outcome, the most common being stable mental health or resilience. We review trajectory research for different types of disasters, including the COVID-19 pandemic. Next, we consider correlates of the resilience trajectory and note their paradoxically limited ability to predict future resilient outcomes. Research using machine learning algorithms improved prediction but has not yet illuminated the mechanism behind resilient adaptation. To that end, we propose a more direct psychological explanation for resilience based on research on the motivational and mechanistic components of regulatory flexibility. Finally, we consider how future research might leverage new computational approaches to better capture regulatory flexibility in real time.


Assuntos
Desastres , Resiliência Psicológica , Humanos , Pandemias , Saúde Mental , Motivação
7.
J Neurophysiol ; 132(3): 979-990, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39110517

RESUMO

5-Hydroxytryptamine (5-HT) plays a substantial role in mitigating depression and anxiety. However, the potential effects of 5-HT against posttraumatic stress disorder (PTSD) and its underlying mechanisms remain unclear. Elevated plus maze test evaluates anxiety-related behaviors, and the open field test is used to assess overall activity levels and anxiety. Inflammatory cytokine levels were determined using ELISA. The levels of 5-HT and dopamine were measured using HPLC. mRNA and protein levels were examined by PCR and Western blot, respectively. Rats exposed to single prolonged stress (SPS) exhibited typical PTSD-like phenotypes, with decreased levels of 5-HT in the hippocampus and significant reductions in its downstream targets, brain-derived neurotrophic factor (BDNF) and TrkB. In addition, it was discovered that the autophagy signaling pathway might be involved in regulating hippocampal BDNF in rats exposed to SPS. Subsequent treatment with an intracerebral injection of sh-SERT significantly inhibited anxiety and cognitive dysfunction in rats. Moreover, sh-SERT treatment was observed to substantially reverse the increase in autophagy signaling protein expression and consequently improve the expression of BDNF and TrkB proteins, which had been reduced. The current study demonstrates that sh-SERT exhibits significant anti-PTSD effects, potentially mediated in part through the reduction of cellular autophagy to enhance hippocampal synaptic plasticity.NEW & NOTEWORTHY The study demonstrated that sh-SERT exhibits significant anti-posttraumatic stress disorder (PTSD) effects, potentially mediated in part through the reduction of cellular autophagy to enhance hippocampal synaptic plasticity.


Assuntos
Autofagia , Fator Neurotrófico Derivado do Encéfalo , Hipocampo , Plasticidade Neuronal , Ratos Sprague-Dawley , Serotonina , Transtornos de Estresse Pós-Traumáticos , Animais , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Transtornos de Estresse Pós-Traumáticos/metabolismo , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Plasticidade Neuronal/efeitos dos fármacos , Plasticidade Neuronal/fisiologia , Masculino , Serotonina/metabolismo , Ratos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Ansiedade/tratamento farmacológico , Receptor trkB/metabolismo , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Modelos Animais de Doenças
8.
J Neurochem ; 168(9): 2587-2600, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38705582

RESUMO

Fear overgeneralization is widely accepted as a pathogenic marker of post-traumatic stress disorder (PTSD). Recently, GABAergic interneurons have been regarded as key players in the regulation of fear memory. The role of hippocampal GABAergic interneurons in contextual fear generalization of PTSD remains incompletely understood. In the present study, we established a rat model of PTSD with inescapable foot shocks (IFS) and observed the loss of GABAergic interneuron phenotype in the hippocampal cornu ammonis-1 (CA1) subfield. To determine whether the loss of GABAergic interneuron phenotype was associated with fear generalization in PTSD rats, we used adeno-associated virus (AAV) to reduce the expression of GAD67 in CA1 and observed its effect on fear generalization. The results showed that the reduction of GAD67 in CA1 enhanced contextual fear generalization in rats. We investigated whether the PERK pathway was involved in the GABAergic interneuron injury. Increased expression of p-PERK, CHOP, and Caspase12 in GABAergic interneurons of PTSD rats was observed. Then, we used salubrinal, an endoplasmic reticulum stress inhibitor, to modulate the PERK pathway. The salubrinal treatment significantly protected the GABAergic interneurons and relieved fear generalization in PTSD rats. In addition, the results showed that salubrinal down-regulated the expression of CHOP and Caspase12 in GABAergic interneurons of PTSD rats. In conclusion, this study provided evidence that the loss of GABAergic interneuron phenotype in CA1 may contribute to contextual fear generalization in PTSD. The PERK pathway is involved in the GABAergic interneuron injury of PTSD rats and modulating it can protect GABAergic interneurons and constrain contextual fear generalization.


Assuntos
Região CA1 Hipocampal , Medo , Neurônios GABAérgicos , Interneurônios , Ratos Sprague-Dawley , Transtornos de Estresse Pós-Traumáticos , Animais , Ratos , Interneurônios/metabolismo , Medo/fisiologia , Medo/psicologia , Masculino , Transtornos de Estresse Pós-Traumáticos/metabolismo , Transtornos de Estresse Pós-Traumáticos/psicologia , Região CA1 Hipocampal/metabolismo , Neurônios GABAérgicos/metabolismo , Generalização Psicológica/fisiologia , Glutamato Descarboxilase/metabolismo
9.
Am J Epidemiol ; 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39038796

RESUMO

Mental health effects are frequently reported following natural disasters. However, little is known about effects of living in a hazard-prone region on mental health. We analyzed data from 9,312 Gulf Long-term Follow-up Study participants who completed standardized mental health questionnaires including the Patient Health Questionnaire-9 (depression=score≥10), Generalized Anxiety Disorder Questionnaire-7 (anxiety=score≥10), and Primary Care PTSD Screen (PTSD=score≥3). Geocoded residential addresses were linked to census-tract level natural hazard risk scores estimated using the National Risk Index (NRI). We considered an overall risk score representing 18 natural hazards, and individual scores for hurricanes, heatwaves, coastal flooding and riverine flooding. Log binomial regression estimated prevalence ratios (PR) and 95% confidence intervals (CI) for associations between risk scores (quartiles) and mental health outcomes. Increasing hurricane and coastal flooding scores were associated with all mental health outcomes in a suggestive exposure-response manner. Associations were strongest for PTSD, with PRs for the highest vs. lowest quartile of hurricane and coastal flooding risks of 2.29(1.74-3.01) and 1.59(1.23-2.05), respectively. High heatwave risk was associated with anxiety (PR=1.25(1.12-1.38)) and depression (PR=1.19(1.04-1.36)) and suggestively with PTSD (PR=1.20(0.94-1.52)). Results suggest that living in areas prone to natural disasters is one factor associated with poor mental health status.

10.
Am J Epidemiol ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39010749

RESUMO

Binge eating disorder (BED) is a public health concern that has received little research attention in military families. Further research is needed to identify risk and protective factors to inform intervention and prevention efforts. This longitudinal study examined predictors of probable BED in a sample of U.S. military spouses (N = 5,269). Data were derived from the Millennium Cohort Family Study, which included baseline assessments of risk and protective factors and a follow-up assessment of probable BED approximately 3 years later. Results of a multivariable logistic regression model indicated that spouses with probable posttraumatic stress disorder, adverse childhood experiences, or who were former smokers had increased risk of probable BED at follow-up. Spouses whose service member had a deployment with combat exposure, or had not deployed, had higher risk of probable BED than spouses whose service member deployed without combat exposure. Age >34 years was the only protective factor to emerge as significant in the adjusted model. Results highlighted the need for interventions to improve psychoeducation and coping skills in military spouses, which may mitigate BED symptoms stemming from military-related stressors (e.g., combat deployment) or prior trauma, especially once maladaptive coping mechanisms (e.g., smoking) have ceased.

11.
Cancer ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39141666

RESUMO

INTRODUCTION: Hematopoietic stem cell transplantation (HCT) is an intensive and invasive procedure used in cancer treatment that can lead to posttraumatic stress disorder (PTSD) symptoms. These symptoms are frequently overlooked in oncology and general health care settings. The suitability and utility of the Primary Care PTSD Screen for DSM-5 (PC-PTSD-5) within the cancer population remains uncertain. This study aims to evaluate its performance as a brief (five-item) case-finding screening alternative to the longer (20-item) PTSD Checklist for DSM-5 (PCL-5) in survivors who received an HCT 1 to 5 years ago. METHODS: A total of 817 cancer survivors completed the PC-PTSD-5 and PCL-5 during recruitment for a randomized clinical trial. Optimal cut scores for identifying probable PTSD and item performance were determined using indices correcting for chance and item response theory analyses. RESULTS: Of the HCT sample, 10.4% screened as positive for probable DSM-5 PTSD using the PCL-5. The PC-PTSD-5 exhibited strong internal consistency and significant associations with PCL-5 scores (total, r = .82; items, rs = .56-.61). A cutoff score of 2 provided optimal sensitivity for screening (κ[Se] = .95), whereas a cut score of 4 demonstrated the highest efficiency for detecting a probable DSM-5 PTSD diagnosis on the PCL-5 (κ[Eff] = .39). Item response theory analyses indicated that item 4 (numbing) of the PC-PTSD-5 yielded the most informative data, with other items potentially lacking incremental utility. CONCLUSION: Although not an instrument validation study, these findings offer efficient evidence for using the PC-PTSD-5 as a succinct screening tool among cancer survivors in a clinical context. TRIALS REGISTRATION: ClinicalTrials.gov, NCT04058795, registered 8/16/2019.

12.
Neurobiol Learn Mem ; 213: 107960, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39004160

RESUMO

Labilization-reconsolidation, which relies on retrieval, has been considered an opportunity to attenuate the negative aspects of traumatic memories. A therapeutic strategy based on reconsolidation blockade is deemed more effective than current therapies relying on memory extinction. Nevertheless, extremely stressful memories frequently prove resistant to this process. Here, after inducing robust fear memory in mice through strong fear conditioning, we examined the possibility of rendering it susceptible to pharmacological modulation based on the degree of generalized fear (GF). To achieve this, we established an ordered gradient of GF, determined by the perceptual similarity between the associated context (CA) and non-associated contexts (CB, CC, CD, and CE) to the aversive event. We observed that as the exposure context became less similar to CA, the defensive pattern shifted from passive to active behaviors in both male and female mice. Subsequently, in conditioned animals, we administered propranolol after exposure to the different contexts (CA, CB, CC, CD or CE). In males, propranolol treatment resulted in reduced freezing time and enhanced risk assessment behaviors when administered following exposure to CA or CB, but not after CC, CD, or CE, compared to the control group. In females, a similar change in behavioral pattern was observed with propranolol administered after exposure to CC, but not after the other contexts. These results highlight the possibility of indirectly manipulating a robust contextual fear memory by controlling the level of generalization during recall. Additionally, it was demonstrated that the effect of propranolol on reconsolidation would not lead to a reduction in fear memory per se, but rather to its reorganization resulting in greater behavioral flexibility (from passive to active behaviors). Finally, from a clinical viewpoint, this would be of considerable relevance since following this strategy could make the treatment of psychiatric disorders associated with traumatic memory formation more effective and less stressful.


Assuntos
Condicionamento Clássico , Medo , Propranolol , Medo/efeitos dos fármacos , Medo/fisiologia , Animais , Masculino , Propranolol/farmacologia , Feminino , Camundongos , Condicionamento Clássico/efeitos dos fármacos , Consolidação da Memória/efeitos dos fármacos , Consolidação da Memória/fisiologia , Camundongos Endogâmicos C57BL , Memória/efeitos dos fármacos , Memória/fisiologia , Generalização Psicológica/efeitos dos fármacos , Generalização Psicológica/fisiologia , Extinção Psicológica/efeitos dos fármacos
13.
Br J Psychiatry ; : 1-3, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38764044

RESUMO

Australia has just rescheduled two drugs controlled under the United Nations Psychotropic Drug Conventions, psilocybin and MDMA, as treatments for treatment-resistant depression and post-traumatic stress disorder respectively. This feature explores the reasons for these developments, the opportunities and challenges they provide to psychiatry communities and how along with health systems these communities might respond to these developments.

14.
Br J Psychiatry ; : 1-3, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39376137

RESUMO

The release of ICD-11 has resulted in an expansion of diagnostic entities for trauma- and stress-related disorders. This resulted, at least temporarily, in discrepancies with the DSM-5. This situation is outlined and a look is taken at the potential diagnosis of 'continuous traumatic stress reaction'.

15.
Psychol Med ; : 1-11, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38775091

RESUMO

BACKGROUND: Knowledge of sex differences in risk factors for posttraumatic stress disorder (PTSD) can contribute to the development of refined preventive interventions. Therefore, the aim of this study was to examine if women and men differ in their vulnerability to risk factors for PTSD. METHODS: As part of the longitudinal AURORA study, 2924 patients seeking emergency department (ED) treatment in the acute aftermath of trauma provided self-report assessments of pre- peri- and post-traumatic risk factors, as well as 3-month PTSD severity. We systematically examined sex-dependent effects of 16 risk factors that have previously been hypothesized to show different associations with PTSD severity in women and men. RESULTS: Women reported higher PTSD severity at 3-months post-trauma. Z-score comparisons indicated that for five of the 16 examined risk factors the association with 3-month PTSD severity was stronger in men than in women. In multivariable models, interaction effects with sex were observed for pre-traumatic anxiety symptoms, and acute dissociative symptoms; both showed stronger associations with PTSD in men than in women. Subgroup analyses suggested trauma type-conditional effects. CONCLUSIONS: Our findings indicate mechanisms to which men might be particularly vulnerable, demonstrating that known PTSD risk factors might behave differently in women and men. Analyses did not identify any risk factors to which women were more vulnerable than men, pointing toward further mechanisms to explain women's higher PTSD risk. Our study illustrates the need for a more systematic examination of sex differences in contributors to PTSD severity after trauma, which may inform refined preventive interventions.

16.
Psychol Med ; 54(6): 1091-1101, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37807886

RESUMO

BACKGROUND: Laboratory paradigms are widely used to study fear learning in posttraumatic stress disorder (PTSD). Recent basic science models demonstrate that, during fear learning, patterns of activity in large neuronal ensembles for the conditioned stimuli (CS) begin to reinstate neural activity patterns for the unconditioned stimuli (US), suggesting a direct way of quantifying fear memory strength for the CS. Here, we translate this concept to human neuroimaging and test the impact of post-learning dopaminergic neurotransmission on fear memory strength during fear acquisition, extinction, and recall among women with PTSD in a re-analysis of previously reported data. METHODS: Participants (N = 79) completed a context-dependent fear acquisition and extinction task on day 1 and extinction recall tests 24 h later. We decoded activity patterns in large-scale functional networks for the US, then applied this decoder to activity patterns toward the CS on day 1 and day 2. RESULTS: US decoder output for the CS+ increased during acquisition and decreased during extinction in networks traditionally implicated in human fear learning. The strength of US neural reactivation also predicted individuals skin conductance responses. Participants randomized to receive L-DOPA (n = 43) following extinction on day 1 demonstrated less US neural reactivation on day 2 relative to the placebo group (n = 28). CONCLUSION: These results support neural reactivation as a measure of memory strength between competing memories of threat and safety and further demonstrate the role of dopaminergic neurotransmission in the consolidation of fear extinction memories.


Assuntos
Medo , Transtornos de Estresse Pós-Traumáticos , Humanos , Feminino , Medo/fisiologia , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Levodopa , Extinção Psicológica/fisiologia , Aprendizagem
17.
Psychol Med ; 54(1): 159-168, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37129070

RESUMO

BACKGROUND: Difficulties in the context-dependent modulation of conditioned fear are known for posttraumatic stress disorder and may explain the occurrence of intrusive memories in safe contexts. The current study therefore investigated if reduced context-dependent modulation of conditioned fear and its underlying neural circuitry constitute risk factors for the development of analog intrusions in response to an experimental trauma. METHODS: Eighty-five healthy women participated in the trauma film paradigm to investigate the development of analog intrusions as well as explicit memory for an experimental trauma after one week and three months, respectively. Before, participants underwent a context-dependent fear conditioning paradigm during functional magnetic resonance imaging with fear acquisition in context A and extinction training in context B on a first day, as well as extinction recall in context B and fear renewal in a novel context C one day later. Skin conductance responses (SCRs) and blood oxygen level dependent responses were main outcome measures. RESULTS: In addition to stronger fear acquisition in context A, stronger conditioned fear responses in the safe context B, as indicated by stronger conditioned SCRs or stronger activation of fear expressing regions during extinction learning and recall, predicted the development of long-term analog intrusions. CONCLUSIONS: Stronger fear responses in safe and danger contexts were risk factors for the development of long-term analog intrusions and point to decontextualized fear memories and difficulties in the context-dependent modulation of conditioned fear. Altered fear conditioning processes and reduced storage of contextual information may cause the occurrence of fear independent of context.


Assuntos
Extinção Psicológica , Resposta Galvânica da Pele , Humanos , Feminino , Extinção Psicológica/fisiologia , Medo/fisiologia , Condicionamento Clássico/fisiologia , Rememoração Mental/fisiologia , Imageamento por Ressonância Magnética
18.
Psychol Med ; : 1-10, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39371009

RESUMO

BACKGROUND: This study examined the power of theory-derived models to account for the development of PTSD, Complex PTSD (CPTSD), depression, and anxiety in children and adolescents who had experienced a single-event trauma. METHODS: Children (n = 234, aged 8-17 years) recruited from local Emergency Departments were assessed at two and nine weeks post-trauma. Data obtained from self-report questionnaires completed by the child, telephone interviews with parents, and hospital data were used to develop four predictive models of risk factors for PTSD, CPTSD, depression, and Generalized Anxiety Disorder (GAD). ICD-11 proposed diagnostic criteria were used to generate measures for CPTSD and PTSD to assess for risk factors and identify the sample prevalence of these disorders. RESULTS: At nine weeks post-trauma, 64% did not meet criteria for any disorder, 23.5% met criteria for PTSD, and 5.2% met criteria for CPTSD. 23.9% and 10.7% had developed clinically significant symptoms of depression and GAD, respectively. A cognitive model was the most powerful predictive model, a psychosocial model was weak, and subjective markers of event severity were more powerful than objective measures. CONCLUSIONS: Youth exposed to single-incident trauma may develop different forms of psychopathology, and PTSD and CPTSD are frequently experienced alongside other conditions. The cognitive model of PTSD shows utility in identifying predictors of PTSD, CPTSD, depression, and GAD, particularly the role of trauma-related negative appraisals. This supports the application of cognitive interventions which focus upon re-appraising trauma-related beliefs in youth.

19.
Psychol Med ; 54(8): 1580-1588, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38173121

RESUMO

BACKGROUND: This systematic review and individual participant data meta-analysis (IPDMA) examined the overall effectiveness of eye movement desensitization and reprocessing (EMDR) in reducing posttraumatic stress disorder (PTSD) symptoms, achieving response and remission, and reducing treatment dropout among adults with PTSD compared to other psychological treatments. Additionally, we examined available participant-level moderators of the efficacy of EMDR. METHODS: This study included randomized controlled trials. Eligible studies were identified by a systematic search in PubMed, Embase, PsyclNFO, PTSDpubs, and CENTRAL. The target population was adults with above-threshold baseline PTSD symptoms. Trials were eligible if at least 70% of study participants had been diagnosed with PTSD using a structured clinical interview. Primary outcomes included PTSD symptom severity, treatment response, and PTSD remission. Treatment dropout was a secondary outcome. The systematic search retrieved 15 eligible randomized controlled trials (RCTs); 8 of these 15 were able to be included in this IPDMA (346 patients). Comparator treatments included relaxation therapy, emotional freedom technique, trauma-focused cognitive behavioral psychotherapies, and REM-desensitization. RESULTS: One-stage IPDMA found no significant difference between EMDR and other psychological treatments in reducing PTSD symptom severity (ß = -0.24), achieving response (ß = 0.86), attaining remission (ß = 1.05), or reducing treatment dropout rates (ß = -0.25). Moderator analyses found unemployed participants receiving EMDR had higher PTSD symptom severity at the post-test, and males were more likely to drop out of EMDR treatment than females. CONCLUSION: The current study found no significant difference between EMDR and other psychological treatments. We found some indication of the moderating effects of gender and employment status.


Assuntos
Dessensibilização e Reprocessamento através dos Movimentos Oculares , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/terapia , Dessensibilização e Reprocessamento através dos Movimentos Oculares/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Adulto , Masculino , Psicoterapia/métodos , Feminino , Terapia Cognitivo-Comportamental/métodos , Resultado do Tratamento
20.
Psychol Med ; 54(3): 437-446, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37947238

RESUMO

Delay discounting-the extent to which individuals show a preference for smaller immediate rewards over larger delayed rewards-has been proposed as a transdiagnostic neurocognitive process across mental health conditions, but its examination in relation to posttraumatic stress disorder (PTSD) is comparatively recent. To assess the aggregated evidence for elevated delay discounting in relation to posttraumatic stress, we conducted a meta-analysis on existing empirical literature. Bibliographic searches identified 209 candidate articles, of which 13 articles with 14 independent effect sizes were eligible for meta-analysis, reflecting a combined sample size of N = 6897. Individual study designs included case-control (e.g. examination of differences in delay discounting between individuals with and without PTSD) and continuous association studies (e.g. relationship between posttraumatic stress symptom severity and delay discounting). In a combined analysis of all studies, the overall relationship was a small but statistically significant positive association between posttraumatic stress and delay discounting (r = .135, p < .0001). The same relationship was statistically significant for continuous association studies (r = .092, p = .027) and case-control designs (r = .179, p < .001). Evidence of publication bias was minimal. The included studies were limited in that many did not concurrently incorporate other psychiatric conditions in the analyses, leaving the specificity of the relationship to posttraumatic stress less clear. Nonetheless, these findings are broadly consistent with previous meta-analyses of delayed reward discounting in relation to other mental health conditions and provide further evidence for the transdiagnostic utility of this construct.


Assuntos
Desvalorização pelo Atraso , Comportamento Problema , Transtornos de Estresse Pós-Traumáticos , Humanos , Recompensa , Viés de Publicação
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