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1.
Front Neurosci ; 17: 1229729, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38094001

RESUMO

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.

2.
Brain Behav ; 13(3): e2883, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36791212

RESUMO

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.


Assuntos
Neocórtex , Neurorretroalimentação , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/terapia , Giro do Cíngulo , Neurorretroalimentação/métodos , Imageamento por Ressonância Magnética , Rede de Modo Padrão/patologia , Encéfalo , Tonsila do Cerebelo , Mapeamento Encefálico
3.
Cerebellum ; 22(6): 1083-1097, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36121553

RESUMO

The flocculus is a region of the vestibulocerebellum dedicated to the coordination of neck, head, and eye movements for optimal posture, balance, and orienting responses. Despite growing evidence of vestibular and oculomotor impairments in the aftermath of traumatic stress, little is known about the effects of chronic psychological trauma on vestibulocerebellar functioning. Here, we investigated alterations in functional connectivity of the flocculus at rest among individuals with post-traumatic stress disorder (PTSD) and its dissociative subtype (PTSD + DS) as compared to healthy controls. Forty-four healthy controls, 57 PTSD, and 32 PTSD + DS underwent 6-min resting-state MRI scans. Seed-based functional connectivity analyses using the right and left flocculi as seeds were performed. These analyses revealed that, as compared to controls, PTSD and PTSD + DS showed decreased resting-state functional connectivity of the left flocculus with cortical regions involved in bodily self-consciousness, including the temporo-parietal junction, the supramarginal and angular gyri, and the superior parietal lobule. Moreover, as compared to controls, the PTSD + DS group showed decreased functional connectivity of the left flocculus with the medial prefrontal cortex, the precuneus, and the mid/posterior cingulum, key regions of the default mode network. Critically, when comparing PTSD + DS to PTSD, we observed increased functional connectivity of the right flocculus with the right anterior hippocampus, a region affected frequently by early life trauma. Taken together, our findings point toward the crucial role of the flocculus in the neurocircuitry underlying a coherent and embodied self, which can be compromised in PTSD and PTSD + DS.


Assuntos
Vermis Cerebelar , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/psicologia , Emoções , Hipocampo , Transtornos Dissociativos , Imageamento por Ressonância Magnética
4.
Artigo em Inglês | MEDLINE | ID: mdl-35627877

RESUMO

Previous research involving healthy participants has reported that seeing a moving virtual body from the first person perspective induces the illusion of ownership and agency over that virtual body. When a person is sitting and the virtual body runs, it is possible to measure physiological, behavioral and cognitive reactions that are comparable to those that occur during actual movement. Capitalizing on this evidence, we hypothesized that virtual training could also induce neuroendocrine effects that prompt a decreased psychosocial stress response, as occurs after physical training. While sitting, 26 healthy young adults watched a virtual avatar running for 30 min from the first person perspective (experimental group), while another 26 participants watched the virtual body from the third person perspective (control group). We found a decreased salivary alpha-amylase concentration (a biomarker for the stress response) after the virtual training among the experimental group only, as well as a decreased subjective feeling of state anxiety (but no difference in heart rate). We argue that the virtual illusion of a moving body from the first person perspective can initiate a cascade of events, from the perception of the visual illusion to physiological activation that triggers other biological effects, such as the neuroendocrine stress response.


Assuntos
Ilusões , Ansiedade , Transtornos de Ansiedade , Humanos , Estresse Psicológico , Interface Usuário-Computador , Adulto Jovem
5.
Brain Behav ; 12(1): e2441, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34921746

RESUMO

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.


Assuntos
Neurorretroalimentação , Transtornos de Estresse Pós-Traumáticos , Regulação para Baixo , Giro do Cíngulo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/terapia
6.
Child Abuse Negl ; 113: 104919, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33476805

RESUMO

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.


Assuntos
Sintomas Afetivos , Emoções , Adulto , Humanos , Inquéritos e Questionários
7.
Front Neurosci ; 14: 586605, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33362457

RESUMO

Peripersonal space (PPS) is defined as the space surrounding the body where we can reach or be reached by external entities, including objects or other individuals. PPS is an essential component of bodily self-consciousness that allows us to perform actions in the world (e.g., grasping and manipulating objects) and protect our body while interacting with the surrounding environment. Multisensory processing plays a critical role in PPS representation, facilitating not only to situate ourselves in space but also assisting in the localization of external entities at a close distance from our bodies. Such abilities appear especially crucial when an external entity (a sound, an object, or a person) is approaching us, thereby allowing the assessment of the salience of a potential incoming threat. Accordingly, PPS represents a key aspect of social cognitive processes operational when we interact with other people (for example, in a dynamic dyad). The underpinnings of PPS have been investigated largely in human models and in animals and include the operation of dedicated multimodal neurons (neurons that respond specifically to co-occurring stimuli from different perceptive modalities, e.g., auditory and tactile stimuli) within brain regions involved in sensorimotor processing (ventral intraparietal sulcus, ventral premotor cortex), interoception (insula), and visual recognition (lateral occipital cortex). Although the defensive role of the PPS has been observed in psychopathology (e.g., in phobias) the relation between PPS and altered states of bodily consciousness remains largely unexplored. Specifically, PPS representation in trauma-related disorders, where altered states of consciousness can involve dissociation from the body and its surroundings, have not been investigated. Accordingly, we review here: (1) the behavioral and neurobiological literature surrounding trauma-related disorders and its relevance to PPS; and (2) outline future research directions aimed at examining altered states of bodily self-consciousness in trauma related-disorders.

8.
Hum Brain Mapp ; 39(11): 4258-4275, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30004602

RESUMO

Posttraumatic stress disorder (PTSD) has been associated with a disturbance in neural intrinsic connectivity networks (ICN), including the central executive network (CEN), default mode network (DMN), and salience network (SN). Here, we conducted a preliminary investigation examining potential changes in ICN recruitment as a function of real-time fMRI neurofeedback (rt-fMRI-NFB) during symptom provocation where we targeted the downregulation of neural response within the amygdala-a key region-of-interest in PTSD neuropathophysiology. Patients with PTSD (n = 14) completed three sessions of rt-fMRI-NFB with the following conditions: (a) regulate: decrease activation in the amygdala while processing personalized trauma words; (b) view: process trauma words while not attempting to regulate the amygdala; and (c) neutral: process neutral words. We found that recruitment of the left CEN increased over neurofeedback runs during the regulate condition, a finding supported by increased dlPFC activation during the regulate as compared to the view condition. In contrast, DMN task-negative recruitment was stable during neurofeedback runs, albeit was the highest during view conditions and increased (normalized) during rest periods. Critically, SN recruitment was high for both the regulate and the view conditions, a finding potentially indicative of CEN modality switching, adaptive learning, and increasing threat/defense processing in PTSD. In conclusion, this study provides provocative, preliminary evidence that downregulation of the amygdala using rt-fMRI-NFB in PTSD is associated with dynamic changes in ICN, an effect similar to those observed using EEG modalities of neurofeedback.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Imageamento por Ressonância Magnética , Neurorretroalimentação , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/terapia , Tonsila do Cerebelo/diagnóstico por imagem , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Neurorretroalimentação/métodos , Dados Preliminares , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Percepção Visual/fisiologia
9.
Front Hum Neurosci ; 12: 163, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29765311

RESUMO

Traumatic experiences have been linked to the development of altered states of consciousness affecting bodily perception, including alterations in body ownership and in sense of agency, the conscious experience of the body as one's own and under voluntary control. Severe psychological trauma and prolonged distress may lead to posttraumatic stress disorder (PTSD). Together, symptoms of derealization and, related specifically to the sense of body ownership and agency, of depersonalization (where parts of the body or the entire body itself is perceived as detached and out of control), constitute the dissociative subtype (PTSD+DS). In this study, we explored the Rubber Hand Illusion, an experimental paradigm utilized to manipulate sense of body ownership in PTSD (n = 4) and PTSD+DS (n = 6) as compared to healthy controls (n = 7). Perceived finger location and self-report questionnaires were used as behavioral and subjective measures of the illusion, respectively. In addition, the correlation between the illusion's effect and sense of agency as a continuous feeling of controlling one's own body movements was explored. Here, a lower illusion effect was observed in the PTSD as compared to the control group after synchronous stimulation for both the proprioceptive drift and subjectively perceived illusion. Moreover, by both proprioceptive drift and by subjective ratings, the PTSD+DS group showed a response characterized by high variance, ranging from a very strong to a very weak effect of the illusion. Finally, sense of agency showed a trend toward a negative correlation with the strength of the illusion as subjectively perceived by participants with PTSD and PTSD+DS. These findings suggest individuals with PTSD may, at times, maintain a rigid representation of the body as an avoidance strategy, with top-down cognitive processes weakening the impact of manipulation of body ownership. By contrast, the response elicited in PTSD+DS appeared to be driven by either an increased vulnerability to manipulation of embodiment or by a dominant top-down cognitive representation of the body, with disruption of multisensory integration processes likely in both cases. Taken together, these findings further our understanding of bodily consciousness in PTSD and its dissociative subtype and highlight the supportive role played by sense of agency for the maintenance of body ownership.

10.
Hum Brain Mapp ; 39(8): 3354-3374, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29667267

RESUMO

The cerebellum plays a key role not only in motor function but also in affect and cognition. Although several psychopathological disorders have been associated with overall cerebellar dysfunction, it remains unclear whether different regions of the cerebellum contribute uniquely to psychopathology. Accordingly, we compared seed-based resting-state functional connectivity of the anterior cerebellum (lobule IV-V), of the posterior cerebellum (Crus I), and of the anterior vermis across posttraumatic stress disorder (PTSD; n = 65), its dissociative subtype (PTSD + DS; n = 37), and non-trauma-exposed healthy controls (HC; n = 47). Here, we observed decreased functional connectivity of the anterior cerebellum and anterior vermis with brain regions involved in somatosensory processing, multisensory integration, and bodily self-consciousness (temporo-parietal junction, postcentral gyrus, and superior parietal lobule) in PTSD + DS as compared to PTSD and HC. Moreover, the PTSD + DS group showed increased functional connectivity of the posterior cerebellum with cortical areas related to emotion regulation (ventromedial prefrontal and orbito-frontal cortex, subgenual anterior cingulum) as compared to PTSD. By contrast, PTSD showed increased functional connectivity of the anterior cerebellum with cortical areas associated with visual processing (fusiform gyrus), interoceptive awareness (posterior insula), memory retrieval, and contextual processing (hippocampus) as compared to HC. Finally, we observed decreased functional connectivity between the posterior cerebellum and prefrontal regions involved in emotion regulation, in PTSD as compared to HC. These findings not only highlight the crucial role of each cerebellar region examined in the psychopathology of PTSD but also reveal unique alterations in functional connectivity distinguishing the dissociative subtype of PTSD versus PTSD.


Assuntos
Cerebelo/diagnóstico por imagem , Cerebelo/fisiopatologia , Transtornos Dissociativos/diagnóstico por imagem , Transtornos Dissociativos/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Descanso , Transtornos de Estresse Pós-Traumáticos/psicologia
11.
Hum Brain Mapp ; 39(3): 1367-1379, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29266586

RESUMO

The bed nucleus of the stria terminals (BNST) is a subcortical structure involved in anticipatory and sustained reactivity to threat and is thus essential to the understanding of anxiety and stress responses. Although chronic stress and anxiety represent a hallmark of post-traumatic stress disorder (PTSD), to date, few studies have examined the functional connectivity of the BNST in PTSD. Here, we used resting state functional Magnetic Resonance Imaging (fMRI) to investigate the functional connectivity of the BNST in PTSD (n = 70), its dissociative subtype (PTSD + DS) (n = 41), and healthy controls (n = 50). In comparison to controls, PTSD showed increased functional connectivity of the BNST with regions of the reward system (ventral and dorsal striatum), possibly underlying stress-induced reward-seeking behaviors in PTSD. By contrast, comparing PTSD + DS to controls, we observed increased functional connectivity of the BNST with the claustrum, a brain region implicated in consciousness and a primary site of kappa-opioid receptors, which are critical to the dynorphin-mediated dysphoric stress response. Moreover, PTSD + DS showed increased functional connectivity of the BNST with brain regions involved in attention and salience detection (anterior insula and caudate nucleus) as compared to PTSD and controls. Finally, BNST functional connectivity positively correlated with default-mode network regions as a function of state identity dissociation, suggesting a role of BNST networks in the disruption of self-relevant processing characterizing the dissociative subtype. These findings represent an important first step in elucidating the role of the BNST in aberrant functional networks underlying PTSD and its dissociative subtype.


Assuntos
Núcleos Septais/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Descanso , Núcleos Septais/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem
12.
Curr Opin Psychol ; 14: 109-115, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28813307

RESUMO

The innate alarm system (IAS), comprised of functionally connected brain regions including the brainstem, amygdala, pulvinar, and frontotemporal cortex, is a fast subcortical brain network facilitating rapid responses to threat. Post-traumatic stress disorder (PTSD) features subconscious and conscious threat detection, together contributing to hyperarousal symptoms. Emerging literature identifies aberrant threat-related neurocircuitry involved in subconscious and conscious threat processing in PTSD. We review this literature, focusing on subconscious threat processing and its relation to the IAS. Available evidence indicates increased neural activity and functional connectivity between IAS brain regions (e.g. locus coeruleus, superior colliculus, amygdala, and prefrontal cortex). These alterations are observed during both subconscious threat processing and at rest, suggesting increased defensive posturing, maintained in the absence of overt threat.

13.
Hum Brain Mapp ; 38(10): 4898-4907, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28714594

RESUMO

BACKGROUND: Posttraumatic stress disorder (PTSD) is characterized by dysregulated arousal and altered cardiac autonomic response as evidenced by decreased high-frequency heart rate variability (HF-HRV), an indirect measure of parasympathetic modulation of the heart. Indeed, subtle threatening cues can cause autonomic dysregulation, even without explicit awareness of the triggering stimulus. Accordingly, examining the neural underpinnings associated with HF-HRV during both sub- and supraliminal exposure to trauma-related cues is critical to an enhanced understanding of autonomic nervous system dysfunction in PTSD. METHODS: We compared neural activity in brain regions associated with HF-HRV in PTSD (n = 18) and healthy controls (n = 18) during exposure to sub- and supraliminal processing of personalized trauma-related words. RESULTS: As compared to controls, PTSD exhibited decreased HF-HRV reactivity in response to sub- and supraliminal cues. Notably, during subliminal processing of trauma-related versus neutral words, as compared to controls, PTSD showed decreased neural response associated with HF-HRV within the left dorsal anterior insula. By contrast, during supraliminal processing of trauma-related versus neutral words, decreased neural activity associated with HF-HRV within the posterior insula/superior temporal cortex, and increased neural activity associated with HF-HRV within the left centromedial amygdala was observed in PTSD as compared to controls. CONCLUSIONS: Impaired parasympathetic modulation of autonomic arousal in PTSD appears related to altered activation of cortical and subcortical regions involved in the central autonomic network. Interestingly, both sub- and supraliminal trauma-related cues appear to elicit dysregulated arousal and may contribute to the maintenance of hyperarousal in PTSD. Hum Brain Mapp 38:4898-4907, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Encéfalo/fisiopatologia , Frequência Cardíaca/fisiologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adulto , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Sinais (Psicologia) , Feminino , Determinação da Frequência Cardíaca , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Análise de Regressão , Índice de Gravidade de Doença , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/psicologia , Estimulação Subliminar
14.
Eur J Psychotraumatol ; 8(1): 1314164, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28649298

RESUMO

Background: Changes to the diagnostic criteria for PTSD in DSM-5 reflect an increased emphasis on negative cognition referring to self and other, including self-blame, and related pervasive negative affective states including for self-conscious emotions such as guilt and shame. Objective: Investigate the neural correlates of valenced self-referential processing (SRP) and other-referential processing (ORP) in persons with PTSD. Method: We compared response to the Visual-Verbal Self-Other Referential Processing Task in an fMRI study of women with (n = 20) versus without (n = 24) PTSD primarily relating to childhood and interpersonal trauma histories using statistical parametric mapping and group independent component analysis. Results: As compared to women without PTSD, women with PTSD endorsed negative words as more descriptive both of themselves and others, whereas positive words were endorsed as less descriptive both of themselves and others. Women with PTSD also reported a greater experience of negative affect and a lesser experience of positive affect during SRP specifically. Significant differences between groups were observed within independent components defined by ventral- and middle-medial prefrontal corte x, mediolateral parietal cortex, and visual cortex, depending on experimental conditions. Conclusions: This study reveals brain-based disturbances during SRP and ORP in women with PTSD related to interpersonal and developmental trauma. Psychological assessment and treatment should address altered sense of self and affective response to others in PTSD.

15.
Hum Brain Mapp ; 38(1): 541-560, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27647695

RESUMO

Amygdala dysregulation has been shown to be central to the pathophysiology of posttraumatic stress disorder (PTSD) representing a critical treatment target. Here, amygdala downregulation was targeted using real-time fMRI neurofeedback (rt-fMRI-nf) in patients with PTSD, allowing us to examine further the regulation of emotional states during symptom provocation. Patients (n = 10) completed three sessions of rt-fMRI-nf with the instruction to downregulate activation in the amygdala, while viewing personalized trauma words. Amygdala downregulation was assessed by contrasting (a) regulate trials, with (b) viewing trauma words and not attempting to regulate. Training was followed by one transfer run not involving neurofeedback. Generalized psychophysiological interaction (gPPI) and dynamic causal modeling (DCM) analyses were also computed to explore task-based functional connectivity and causal structure, respectively. It was found that PTSD patients were able to successfully downregulate both right and left amygdala activation, showing sustained effects within the transfer run. Increased activation in the dorsolateral and ventrolateral prefrontal cortex (PFC), regions related to emotion regulation, was observed during regulate as compared with view conditions. Importantly, activation in the PFC, rostral anterior cingulate cortex, and the insula, were negatively correlated to PTSD dissociative symptoms in the transfer run. Increased functional connectivity between the amygdala- and both the dorsolateral and dorsomedial PFC was found during regulate, as compared with view conditions during neurofeedback training. Finally, our DCM analysis exploring directional structure suggested that amygdala downregulation involves both top-down and bottom-up information flow with regard to observed PFC-amygdala connectivity. This is the first demonstration of successful downregulation of the amygdala using rt-fMRI-nf in PTSD, which was critically sustained in a subsequent transfer run without neurofeedback, and corresponded to increased connectivity with prefrontal regions involved in emotion regulation during the intervention. Hum Brain Mapp 38:541-560, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Encéfalo/diagnóstico por imagem , Emoções/fisiologia , Imageamento por Ressonância Magnética , Transtornos de Estresse Pós-Traumáticos/patologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Análise de Variância , Retroalimentação Sensorial/fisiologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Modelos Neurológicos , Oxigênio/sangue , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem
16.
Brain Behav ; 6(12): e00579, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-28032002

RESUMO

BACKGROUND: Posttraumatic stress disorder (PTSD) is associated with hyperarousal and active fight or flight defensive responses. By contrast, the dissociative subtype of PTSD, characterized by depersonalization and derealization symptoms, is frequently accompanied by additional passive or submissive defensive responses associated with autonomic blunting. Here, the periaqueductal gray (PAG) plays a central role in defensive responses, where the dorsolateral (DL-PAG) and ventrolateral PAG (VL-PAG) are thought to mediate active and passive defensive responses, respectively. METHODS: We examined PAG subregion (dorsolateral and ventrolateral) resting-state functional connectivity in three groups: PTSD patients without the dissociative subtype (n = 60); PTSD patients with the dissociative subtype (n = 37); and healthy controls (n = 40) using a seed-based approach via PickAtlas and SPM12. RESULTS: All PTSD patients showed extensive DL- and VL-PAG functional connectivity at rest with areas associated with emotional reactivity and defensive action as compared to controls (n = 40). Although all PTSD patients demonstrated DL-PAG functional connectivity with areas associated with initiation of active coping strategies and hyperarousal (e.g., dorsal anterior cingulate; anterior insula), only dissociative PTSD patients exhibited greater VL-PAG functional connectivity with brain regions linked to passive coping strategies and increased levels of depersonalization (e.g., temporoparietal junction; rolandic operculum). CONCLUSIONS: These findings suggest greater defensive posturing in PTSD patients even at rest and demonstrate that those with the dissociative subtype show unique patterns of PAG functional connectivity when compared to those without the subtype. Taken together, these findings represent an important first step toward identifying neural and behavioral targets for therapeutic interventions that address defensive strategies in trauma-related disorders.


Assuntos
Substância Cinzenta Periaquedutal/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adulto , Estudos de Casos e Controles , Conectoma , Transtornos Dissociativos/diagnóstico por imagem , Transtornos Dissociativos/fisiopatologia , Transtornos Dissociativos/psicologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Substância Cinzenta Periaquedutal/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/psicologia
17.
Eur J Psychotraumatol ; 7: 32918, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27876453

RESUMO

BACKGROUND: Early traumatic experiences are thought to be causal factors in the development of trauma-related dissociative experiences, including depersonalization and derealization. The rubber hand illusion (RHI), a well-known paradigm that measures multi-sensorial integration of a rubber hand into one's own body representation, has been used to investigate alterations in the experience of body ownership and of body representation. Critically, however, it has never been studied in individuals with trauma-related disorders. OBJECTIVE: To investigate body representation distortions occurring in trauma-related disorders in response to the RHI. METHOD: The RHI was administered to three individuals with the dissociative subtype of posttraumatic stress disorder (PTSD), and subjective, behavioral, cardiovascular and skin conductance responses were recorded. RESULTS: Participants' subjective experiences of the RHI were differentiated and complex. The illusion was induced following both synchronous and asynchronous brushing and variably evoked subjective distress, depersonalization and derealization experiences, tonic immobility, increased physiological arousal and flashbacks. CONCLUSIONS: The present findings point towards the RHI as a strong provocation stimulus that elicits individual patterns of symptom presentation, including experiences of distress and dissociation, in individuals with trauma-related disorders, including the dissociative subtype of PTSD. HIGHLIGHTS OF THE ARTICLE: The rubber hand illusion (RHI) elicits distress, tonic immobility, depersonalization and derealization, and autonomic responses in individuals with trauma-related disorders, including the dissociative subtype of posttraumatic stress disorder (PTSD). RHI effects related to body misrepresentation may trigger altered experiences related to body ownership. The RHI represents a promising paradigm for studying the neurophenomenology of body distortion in individuals experiencing trauma-related altered states of consciousness (TRASC).

18.
PLoS One ; 11(11): e0166357, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27835675

RESUMO

This research aims to explore the neural correlates involved in altruistic punishment, parochial altruism and anti-social punishment, using the Third-Party Punishment (TPP) game. In particular, this study considered these punishment behaviors in in-group vs. out-group game settings, to compare how people behave with members of their own national group and with members of another national group. The results showed that participants act altruistically to protect in-group members. This study indicates that norm violation in in-group (but not in out-group) settings results in increased activity in the medial prefrontal cortex and temporo-parietal junction, brain regions involved in the mentalizing network, as the third-party attempts to understand or justify in-group members' behavior. Finally, exploratory analysis during anti-social punishment behavior showed brain activation recruitment of the ventromedial prefrontal cortex, an area associated with altered regulation of emotions.


Assuntos
Altruísmo , Lobo Parietal/fisiologia , Córtex Pré-Frontal/fisiologia , Punição/psicologia , Lobo Temporal/fisiologia , Adulto , Mapeamento Encefálico , Emoções/fisiologia , Jogos Experimentais , Humanos , Imageamento por Ressonância Magnética , Masculino , Lobo Parietal/anatomia & histologia , Córtex Pré-Frontal/anatomia & histologia , Lobo Temporal/anatomia & histologia
19.
PLoS One ; 11(9): e0163097, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27631496

RESUMO

Post-traumatic stress disorder (PTSD) is characterized by altered functional connectivity of the amygdala complexes at rest. However, amygdala complex connectivity during conscious and subconscious threat processing remains to be elucidated. Here, we investigate specific connectivity of the centromedial amygdala (CMA) and basolateral amygdala (BLA) during conscious and subconscious processing of trauma-related words among individuals with PTSD (n = 26) as compared to non-trauma-exposed controls (n = 20). Psycho-physiological interaction analyses were performed using the right and left amygdala complexes as regions of interest during conscious and subconscious trauma word processing. These analyses revealed a differential, context-dependent responses by each amygdala seed during trauma processing in PTSD. Specifically, relative to controls, during subconscious processing, individuals with PTSD demonstrated increased connectivity of the CMA with the superior frontal gyrus, accompanied by a pattern of decreased connectivity between the BLA and the superior colliculus. During conscious processing, relative to controls, individuals with PTSD showed increased connectivity between the CMA and the pulvinar. These findings demonstrate alterations in amygdala subregion functional connectivity in PTSD and highlight the disruption of the innate alarm network during both conscious and subconscious trauma processing in this disorder.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Br J Health Psychol ; 21(3): 584-99, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26932132

RESUMO

OBJECTIVES: The aim of this study was to verify the efficacy of a manualized, cognitively oriented psychological intervention, called Mental Fitness, in improving the mental and physical health of patients with acute coronary syndrome (ACS). Mental Fitness is a small-group four-session treatment aimed at increasing awareness of one's own bodily perceptions, emotions, and thoughts and is overall tailored on participants' perception of control over their health. DESIGN: Prospective randomized controlled single-blind trial. METHODS: Patients with ACS were recruited within a week from their acute cardiac event. Patients in the intervention group underwent one of two variants of Mental Fitness, depending on their perceived (internal or external) control over their health. Patients in the control group underwent standard treatment. All the patients were submitted to a clinical and psychological follow-up for 8 months. RESULTS: The patients who underwent the Mental Fitness intervention (N = 31) showed, compared to the control patients (N = 34), increased quality of life in its physical, psychological, social and environmental domains, more functional emotional and problem-centred coping strategies, and higher emotional awareness. They also showed improved high-density lipoprotein cholesterol, triglycerides, heart rate, and left ventricular ejection fraction compared to the controls. In addition, they were more successful in maintaining physical exercise. CONCLUSIONS: This study demonstrates the efficacy of Mental Fitness in modifying specific psychological and physical variables conditioning cardiological patients' prognosis. It also confirms the importance of differentiating psychological interventions based on the psychological characteristics of the patients. Statement of contribution What is already known on this subject? Traditional symptom-based interventions in heart disease are aimed at diagnosing and reducing psychological symptomatology (e.g., depression), but recent work has shown the usefulness of orienting psychological interventions to patients' representations of themselves and of the world and to how such representations influence their thoughts, feelings, and behaviours (e.g., Chiavarino et al., ). What does this study add? Mental Fitness, by working on awareness of bodily perceptions, emotions, and thoughts, leads to positive changes in physical and psychological health. Mental Fitness is a cost-effective psychological intervention that adds significantly to the effectiveness of standard medical care.


Assuntos
Síndrome Coronariana Aguda/psicologia , Síndrome Coronariana Aguda/reabilitação , Conhecimentos, Atitudes e Prática em Saúde , Educação de Pacientes como Assunto/métodos , Adaptação Psicológica , Conscientização , Exercício Físico/psicologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Qualidade de Vida/psicologia , Método Simples-Cego , Resultado do Tratamento
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