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Exposure-based therapy is effective in treating anxiety, but a return of fear in the form of relapse is common. Exposure is based on the extinction of Pavlovian fear conditioning. Both animal and human studies point to increased arousal during immediate compared to delayed extinction (>+24 h), which presumably impairs extinction learning and increases the subsequent return of fear. Impaired extinction learning under arousal might interfere with psychotherapeutic interventions. The aim of the present study was to investigate whether arousal before extinction differs between extinction groups and whether arousal before extinction predicts the return of fear in a later (retention) test. As a highlight, both the time between fear acquisition and extinction (immediate vs. delayed) and the time between extinction and test (early vs. late test) were systematically varied. We performed follow-up analyses on data from 103 young, healthy participants to test the above hypotheses. Subjective arousal ratings and physiological arousal measures of sympathetic and hypothalamic pituitary adrenal axis activation (tonic skin conductance and salivary cortisol) were collected. Increased pre-extinction arousal in the immediate extinction group was only confirmed for subjective arousal. In linear regression analyses, none of the arousal measures predicted a significant return of fear in the different experimental groups. Only when we aggregated across the two test groups, tonic skin conductance at the onset of extinction predicted the return of fear in skin conductance responses. The overall results provide little evidence that pre-extinction arousal affects subsequent extinction learning and memory. In terms of clinical relevance, there is no clear evidence that exposure could be improved by reducing subjective or physiological arousal.
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Resposta Galvânica da Pele , Sistema Hipotálamo-Hipofisário , Animais , Humanos , Extinção Psicológica/fisiologia , Sistema Hipófise-Suprarrenal , Medo/fisiologia , Nível de Alerta/fisiologiaRESUMO
Appetitive conditioning plays an important role in the development and maintenance of pornography-use and gaming disorders. It is assumed that primary and secondary reinforcers are involved in these processes. Despite the common use of pornography and gaming in the general population appetitive conditioning processes in this context are still not well studied. This study aims to compare appetitive conditioning processes using primary (pornographic) and secondary (monetary and gaming-related) rewards as unconditioned stimuli (UCS) in the general population. Additionally, it investigates the conditioning processes with gaming-related stimuli as this type of UCS was not used in previous studies. Thirty-one subjects participated in a differential conditioning procedure in which four geometric symbols were paired with either pornographic, monetary, or gaming-related rewards or with nothing to become conditioned stimuli (CS + porn, CS + game, CS + money, and CS-) in an functional magnetic resonance imaging study. We observed elevated arousal and valence ratings as well as skin conductance responses for each CS+ condition compared to the CS-. On the neural level, we found activations during the presentation of the CS + porn in the bilateral nucleus accumbens, right medial orbitofrontal cortex, and the right ventral anterior cingulate cortex compared to the CS-, but no significant activations during CS + money and CS + game compared to the CS-. These results indicate that different processes emerge depending on whether primary and secondary rewards are presented separately or together in the same experimental paradigm. Additionally, monetary and gaming-related stimuli seem to have a lower appetitive value than pornographic rewards.
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Mapeamento Encefálico , Literatura Erótica , Resposta Galvânica da Pele , Imageamento por Ressonância Magnética , Recompensa , Humanos , Masculino , Adulto Jovem , Adulto , Feminino , Resposta Galvânica da Pele/fisiologia , Jogos de Vídeo , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Condicionamento Clássico/fisiologia , Nível de Alerta/fisiologiaRESUMO
BACKGROUND: There are phenomenological similarities between social anxiety disorder (SAD) and posttraumatic stress disorder, such as a provoking aversive event, posttraumatic stress symptoms (e.g. intrusions) in response to these events and deficient (context-dependent) fear conditioning processes. This study investigated the neural correlates of context-dependent extinction recall and fear renewal in SAD, specifically in patients with intrusions in response to an etiologically relevant aversive social event. METHODS: During functional magnetic resonance imaging a two-day context-dependent fear conditioning paradigm was conducted in 54 patients with SAD and 54 healthy controls (HC). This included fear acquisition (context A) and extinction learning (context B) on one day, and extinction recall (context B) as well as fear renewal (contexts C and A) one day later. The main outcome measures were blood oxygen level-dependent responses in regions of interest and skin conductance responses. RESULTS: Patients with SAD showed reduced differential conditioned amygdala activation during extinction recall in the safe extinction context and during fear renewal in the acquisition context compared to HC. Patients with clinically relevant intrusions moreover exhibited hypoactivation of the ventromedial prefrontal cortex (vmPFC) during extinction learning, extinction recall, and fear renewal in a novel context, while amygdala activation more strongly decreased during extinction learning and increased during fear renewal in the acquisition context compared with patients without intrusions. CONCLUSIONS: Our study provides first evidence that intrusions in SAD are associated with similar deficits in context-dependent regulation of conditioned fear via the vmPFC as previously demonstrated in posttraumatic stress disorder.
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Fobia Social , Humanos , Fobia Social/diagnóstico por imagem , Condicionamento Clássico/fisiologia , Extinção Psicológica/fisiologia , Resposta Galvânica da Pele , Rememoração Mental/fisiologia , Imageamento por Ressonância Magnética/métodosRESUMO
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.
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Extinção Psicológica , Resposta Galvânica da Pele , Humanos , Feminino , Extinção Psicológica/fisiologia , Medo/fisiologia , Condicionamento Clássico/fisiologia , Rememoração Mental/fisiologia , Imageamento por Ressonância MagnéticaRESUMO
INTRODUCTION: Imagery rescripting (ImRs) is a psychotherapeutic intervention targeting aversive memories. During the three-phase intervention, patients reexperience their aversive memory (phase 1), observe the scene from their adult perspective, and intervene to help their former selves (phase 2), and reexperience it again with the positive changes (phase 3). Previous studies have rarely investigated emotional and regulatory processes taking place during the intervention. OBJECTIVE: This randomized controlled trial investigated self-reported affective and physiological responses during ImRs. METHODS: Seventy-seven patients with social anxiety disorder (SAD) were randomly assigned to a single session of ImRs or a control intervention (recall and discussion of the memory) targeting an aversive social memory. Heart rate (HR) and heart rate variability (HRV) were assessed during and post hoc ratings of positive and negative feelings after baseline and the intervention phases. RESULTS: Relative to the control intervention, ImRs resulted in an initial increase in negative feelings from baseline to phase 1 and a following larger (phase 1 to phase 2) and more stable (phase 2 to phase 3) decrease in negative feelings/increase in positive feelings. On the physiological level, during ImRs compared to the control intervention, mean HR was significantly higher during phase 1 and HRV during phase 3, each compared to baseline. CONCLUSIONS: These results provide further information about the specific sequence of emotional responses on different response levels during ImRs, being consistent with known theories of emotional processing and supposed mechanisms of ImRs.
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Emoções , Frequência Cardíaca , Imagens, Psicoterapia , Fobia Social , Humanos , Fobia Social/terapia , Fobia Social/psicologia , Feminino , Masculino , Adulto , Frequência Cardíaca/fisiologia , Imagens, Psicoterapia/métodos , Emoções/fisiologia , Pessoa de Meia-Idade , Rememoração Mental/fisiologia , MemóriaRESUMO
Anxiety disorders are effectively treated with exposure therapy based on the extinction of Pavlovian fear conditioning. Animal research indicates that both the timing of extinction and test are important factors to reduce the return of fear. However, empirical evidence in humans is incomplete and inconsistent. In this neuroimaging study, we, therefore, tested 103 young, healthy participants in a 2-factorial between-subjects design with the factors extinction group (immediate, delayed) and test group (+1 day and +7 days). Immediate extinction led to greater retention of fear memory at the beginning of extinction training indicated by increased skin conductance responses. A return of fear was observed in both extinction groups, with a trend toward a greater return of fear in immediate extinction. The return of fear was generally higher in groups with an early test. Neuroimaging results show successful cross-group fear acquisition and retention, as well as activation of the left nucleus accumbens during extinction training. Importantly, the delayed extinction group showed a larger bilateral nucleus accumbens activation during test. This nucleus accumbens finding is discussed in terms of salience, contingency, relief, and prediction error processing. It may imply that the delayed extinction group benefits more from the test as a new learning opportunity.
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Extinção Psicológica , Medo , Animais , Humanos , Extinção Psicológica/fisiologia , Medo/fisiologia , Condicionamento Clássico/fisiologia , Resposta Galvânica da PeleRESUMO
OBJECTIVE: Research suggests that some therapists achieve better outcomes than others. However, an overlooked area of study is how institution differences impact patient outcomes independent of therapist variance. This study aimed to examine the role of institution and therapist differences in adult outpatient psychotherapy. METHOD: The study included 1428 patients who were treated by 196 therapists at 10 clinics. Two- and three-level hierarchical linear regression models were employed to investigate the effects of therapists and institutions on three dependent patient variables: (1) symptom change, (2) treatment duration, and (3) dropout. Level three explanatory variables were tested. RESULTS: The results showed that therapist effects (TE) were significant for all three types of treatment outcome (7.8%-18.2%). When a third level (institution) was added to the model, the differences between therapists decreased, and significant institution effects (IE) were found: 6.3% for symptom change, 10.6% for treatment duration, and 6.5% for dropout. The exploratory analyses found no predictors able to explain the systematic variation at the institution level. DISCUSSION: TE on psychotherapy outcomes remain a relevant factor but may have been overestimated in previous studies due to not properly distinguishing them from differences at the institution level.
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Reinterpretation and distancing, two cognitive reappraisal tactics, are known to effectively reduce negative feelings and event-related potentials (ERPs), such as the P300 and the late positive potential (LPP), in the short-term. Less is known about differential and lasting effects on ERPs as well as their association with habitual reappraisal. Fifty-seven participants were instructed to passively view or reappraise (reinterpretation, distancing) pictures that were repeatedly presented with the same instruction (active regulation phase). Thirty minutes later, these pictures were shown again without instruction for the assessment of lasting effects (re-exposure phase). ERPs were recorded and participants rated the intensity of negative feelings following picture presentation. Reappraisal led to an attenuation of the LPP, and both tactics decreased negative feelings during active regulation, whereby reinterpretation had a stronger impact on the subjective level. Passive re-exposure resulted in reduced negative feelings for previously reappraised pictures but had no lasting effects on ERPs. Higher habitual reappraisal was associated with higher P300 and early LPP amplitudes for emotional reactivity during the active regulation phase. During the re-exposure phase, higher habitual reappraisal was not related to ERPs. The current findings emphasize the effectiveness of both tactics in the short-term and lasting effects on the subjective experience of negative feelings. Enhanced emotional reactivity on the electrocortical level in individuals with a more frequent habitual use of reappraisal might indicate a higher preparedness to regulate.
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Terapia de Reestruturação Cognitiva , Emoções , Potenciais Evocados , Hábitos , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Análise de Dados , Regulação Emocional/fisiologia , Estimulação LuminosaRESUMO
Previous studies suggest there is a complex relationship between sexual and general affective stimulus processing, which varies across individuals and situations. We examined whether sexual and general affective processing can be distinguished at the brain level. In addition, we explored to what degree possible distinctions are generalizable across individuals and different types of sexual stimuli, and whether they are limited to the engagement of lower-level processes, such as the detection of visual features. Data on sexual images, nonsexual positive and negative images, and neutral images from Wehrum et al. (2013) (N = 100) were reanalyzed using multivariate support vector machine models to create the brain activation-based sexual image classifier (BASIC) model. This model was tested for sensitivity, specificity, and generalizability in cross-validation (N = 100) and an independent test cohort (N = 18; Kragel et al. 2019). The BASIC model showed highly accurate performance (94-100%) in classifying sexual versus neutral or nonsexual affective images in both datasets with forced choice tests. Virtual lesions and tests of individual large-scale networks (e.g., visual or attention networks) show that individual networks are neither necessary nor sufficient to classify sexual versus nonsexual stimulus processing. Thus, responses to sexual images are distributed across brain systems.
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Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador/métodos , Máquina de Vetores de SuporteRESUMO
BACKGROUND: Gaming disorder (GD) is a disorder due to addictive behaviors (ICD-11). Cue-reactivity and craving are relevant mechanisms in the development and maintenance of addictive behaviors. When confronted with cues showing in-game content (proximal cues) individuals with higher symptom severity show increased cue-reactivity. Based on conditioning and addiction theories on incentive sensitization, cue-reactivity responses may generalize to more distal cues, e.g. when individuals at risk of developing a GD are confronted with a starting page of an online game. In cue-reactivity paradigms so far, only proximal gaming cues have been used. METHODS: We investigated the effect of distal gaming cues compared to gaming-unrelated control cues on cue-reactivity and craving in 88 individuals with non-problematic use of online games (nPGU) and 69 individuals at risk for GD (rGD). The distal cues showed the use of an electronic device (e.g., desktop PC or smartphone) whose screen showed starting pages of either games (target cues), shopping- or pornography sites (control cues) from a first-person perspective. FINDINGS: We found significantly higher urge and arousal ratings as well as longer viewing times for gaming-related compared to gaming-unrelated control cues in rGD compared to nPGU. Valence ratings did not differ between groups. INTERPRETATION: The results demonstrate that already distal gaming-specific cues lead to cue-reactivity and craving in rGD. This finding indicates that based on conditioning processes, cue-reactivity and craving develop during the course of GD and generalize to cues that are only moderately related to the specific gaming activity.
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Comportamento Aditivo , Jogos de Vídeo , Humanos , Sinais (Psicologia) , Jogos de Vídeo/efeitos adversos , Comportamento Aditivo/diagnóstico , Fissura/fisiologia , Oligopeptídeos , Imageamento por Ressonância Magnética/métodosRESUMO
Sharing imaging data and comparing them across different psychological tasks is becoming increasingly possible as the open science movement advances. Such cross-paradigm integration has the potential to identify commonalities in findings that neighboring areas of study thought to be paradigm-specific. However, even the integration of research from closely related paradigms, such as aversive and appetitive classical conditioning is rare - even though qualitative comparisons already hint at how similar the 'fear network' and 'reward network' may be. We aimed to validate these theories by taking a multivariate approach to assess commonalities across paradigms empirically. Specifically, we quantified the similarity of an aversive conditioning pattern derived from meta-analysis to appetitive conditioning fMRI data. We tested pattern expression in three independent appetitive conditioning studies with 29, 76 and 38 participants each. During fMRI scanning, participants in each cohorts performed an appetitive conditioning task in which a CS+ was repeatedly rewarded with money and a CS- was never rewarded. The aversive pattern was highly similar to appetitive CS+ > CS- contrast maps across samples and variations of the appetitive conditioning paradigms. Moreover, the pattern distinguished the CS+ from the CS- with above-chance accuracy in every sample. These findings provide robust empirical evidence for an underlying neural system common to appetitive and aversive learning. We believe that this approach provides a way to empirically integrate the steadily growing body of fMRI findings across paradigms.
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Condicionamento Clássico , Condicionamento Psicológico , Humanos , Medo , Recompensa , Aprendizagem da EsquivaRESUMO
BACKGROUND: Sexual dysfunctions are commonly associated with depression by which women are particularly affected. AIM: In the following study, we looked at which stage-early attention-related processes or later evaluation-related processes-of the processing of sexual stimuli deviations occur in depressed individuals. METHODS: We examined 96 women who either suffered from a major depressive disorder, or had recovered from it, and a healthy control group. The early level of attention processes was represented by reaction time tasks (dot probe, line orientation, picture categorization). In addition, implicit approach and avoidance behavior was tested by the Approach-Avoidance Task. Later evaluation of the visual material was determined with the help of a questionnaire for recording automatic negative thoughts regarding sexuality. OUTCOMES: Reaction times and explicit ratings as well as the Becks Depression Inventory (BDI II), the Trait Sexual Motivation Questionnaire (TSMQ), the Sexual Modes Questionnaire (SMQ) and a screening for sexual dysfunction were used. RESULTS: Depressed women did not differ significantly from healthy women in their attention processes and approach-avoidance behavior. However, there were clear differences in explicit assessment and automatic thoughts about sexual stimuli. Women who had recovered from depression lay between the 2 groups. CLINICAL IMPLICATIONS: The results indicated that the therapy of sexual dysfunction in depressed patients should focus more on automatic thoughts than on attention processes. STRENGTHS & LIMITATIONS: This study is the first to experimentally research the attention processes of depression towards sexual stimuli. However, participants were only tested on one occasion so that change of attention processes and evaluation of sexual stimuli over the course of a depression could not be assessed. CONCLUSION: Our novel findings demonstrate the role of attention processes in sexual dysfunctions of depressed women and suggest potential mechanisms that may underlie the observed correlation between depression and sexual dysfunction. Baranowski AM, Noll A-K, Golder S, et al. Effects of Depression on Processing and Evaluation of Sexual Stimuli in Women. J Sex Med 2022;19:441-451.
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Transtorno Depressivo Maior , Disfunções Sexuais Fisiológicas , Disfunções Sexuais Psicogênicas , Depressão , Transtorno Depressivo Maior/complicações , Feminino , Humanos , Comportamento Sexual , SexualidadeRESUMO
The experience of socially aversive events is proposed to be a critical etiological factor in the development of social anxiety symptoms even though the experience itself is also common among healthy individuals. Rather than the event itself, accompanying factors such as maladaptive processing might be associated with higher levels of social anxiety symptoms. One-hundred-seventy-four individuals participated in this online-survey comprising questionnaires regarding social anxiety symptoms and retrospective reports concerning maladaptive processing of the worst socially aversive event. Structural equation modelling was used to analyze the hypothesized mediation of maladaptive processing and fear of negative evaluation by intrusive re-experiencing and social phobic beliefs. The positive association between retrospectively evaluated maladaptive processing after the worst socially aversive event and fear of negative evaluation was mediated by social phobic beliefs but not by intrusive re-experiencing. These results point towards the relevance of further investigating processing strategies after socially aversive events as a potential influencing factor for SAD development. Trial registration. The trial was registered at the German Clinical Trial Register (DRKS00021502) on June 3rd, 2020. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12144-022-02805-9.
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OBJECTIVE: Symptoms of exercise addiction, a state of compulsively engaging in intense exercise, and orthorexic eating attitudes, the obsession with eating only healthy foods, often occur together. It is assumed that some more general psychological traits underlie this association. Main aim of this report was to examine similarities and differences between orthorexic eating and addictive exercising. METHOD: Six hundred and eight individuals completed an online survey (mean age: 27.5, SD = 11.0 years; 76.5% women) measuring exercise addiction (Exercise Addiction inventory, EAI), orthorexic eating (Düsseldorfer Orthorexie Skala, DOS), personality domains (Big-Five Inventory-10), anxiety and depression (Hospital Anxiety and Depression Scale). RESULTS: Correlations between the DOS and EAI were .43 in women and .62 in men. Structural equation models identified gender-specific as well as behavior-specific psychological correlates. Among women, anxiety correlated with both EAI and DOS. In addition, the DOS correlated with depression and neuroticism while the EAI correlated with conscientiousness. In men, both scales were associated with conscientiousness and the EAI also correlated with extraversion. Clusterability analysis provided no evidence for clusters based on DOS and EAI. DISCUSSION: Present results showed a substantial correlation between addictive exercising and orthorexic eating, however, coefficients were smaller than expected and appeared higher in men. Both behaviors shared few psychological traits (anxiety in women, conscientiousness in men) thereby questioning the assumption of a similar origin. Additionally, gender-specific psychological correlates point to the need for different disease management approaches in women and men.
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Comportamento Alimentar , Transtornos da Alimentação e da Ingestão de Alimentos , Adulto , Ansiedade , Exercício Físico , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico , Feminino , Humanos , Masculino , Personalidade , Inquéritos e QuestionáriosRESUMO
In the eleventh International Classification of Diseases (ICD-11) of the World Health Organization, gambling disorder and gaming disorder are included in the category 'disorders due to addictive behaviours', which can be specified further as occurring either predominantly offline or predominantly online. Other specific problematic behaviours may be considered for the category 'other specified disorders due to addictive behaviours'. The Research Unit FOR 2974, funded by the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG), focuses on the most prominent online addictive behaviours: gaming, pornography use, buying-shopping and social-networks use. The main goal of the Research Unit is to contribute to a better understanding of the common and differential psychological as well as neurobiological mechanisms involved in these specific types of Internet-use disorders. We aim to investigate theoretically argued (bio)psychological processes with a focus on concepts coming from research of substance-use disorders, for example, cue reactivity and craving, executive functions and specific inhibitory control, coping, implicit cognitions, and decision making. One central characteristic of the Research Unit is that we will investigate all participants using a comprehensive core battery of experimental paradigms, neuropsychological tasks, questionnaires, biomarkers, ambulatory assessment, and a 6-month follow-up survey. Beyond the anticipated contributions to the scientific understanding of the mechanisms involved in the development and maintenance of respective online addictive behaviours, we also expect contributions to clinical practice by showing which affective and cognitive mechanisms may be addressed more intensively to optimize treatment.
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Academias e Institutos/organização & administração , Transtorno de Adição à Internet/fisiopatologia , Transtorno de Adição à Internet/psicologia , Fissura/fisiologia , Sinais (Psicologia) , Tomada de Decisões/fisiologia , Função Executiva/fisiologia , Alemanha , HumanosRESUMO
Extinction of appetitive conditioning is regarded as an important model for the treatment of psychiatric disorders like addiction. However, very few studies have investigated its neural correlates. Therefore, we investigated neural correlates of appetitive extinction in a large human sample including all genders (N = 76, 40 females) to replicate and extend results from a previous study. During differential appetitive conditioning, one stimulus (CS+) was paired with the chance to win a monetary reward, whereas another stimulus (CS-) was not. During appetitive extinction on the next day, neither the CS+ nor the CS- were reinforced. After successful acquisition of appetitive conditioning, the extinction phase elicited significant reductions of valence and arousal ratings toward the CS+ and a significant reduction in skin conductance responses to the CS+ from early to late extinction. On a neural level, early extinction showed significant differential (CS+ - CS-) activation in dACC and hippocampus, whereas involvement of the vACC and caudate nucleus did not replicate. The differential activation of amygdala and nucleus accumbens during late extinction was replicated, with the amygdala displaying significantly higher differential activation during the late phase of extinction as compared to the early phase of extinction. We show discernible signals for reward learning and extinction in subregions of amygdala and nucleus accumbens after extinction learning. This successful replication underlines the role of nucleus accumbens and amygdala in neural models of appetitive extinction in humans that was previously only based on animal findings.
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Tonsila do Cerebelo/fisiologia , Apetite/fisiologia , Extinção Psicológica/fisiologia , Núcleo Accumbens/fisiologia , Tonsila do Cerebelo/diagnóstico por imagem , Núcleo Caudado/diagnóstico por imagem , Núcleo Caudado/fisiologia , Condicionamento Operante , Feminino , Resposta Galvânica da Pele , Humanos , Aprendizagem , Imageamento por Ressonância Magnética , Masculino , Motivação , Núcleo Accumbens/diagnóstico por imagem , Recompensa , Adulto JovemRESUMO
Exposure therapy is a successful treatment for patients with anxiety and fear-related disorders. Extinction of conditioned fear comprises one important mechanism underlying the effects of exposure therapy. Yet, relapses frequently occur in the long-term, probably related to difficulties in generalizing the extinction of conditioned fear to new contexts, leading to renewal of conditioned fear. Extinction training in multiple extinction contexts depicts a promising opportunity to reduce this renewal of conditioned fear. However, the underlying neural correlates are unknown yet. In this functional magnetic resonance imaging study, 49 healthy men participated in a fear conditioning paradigm with fear acquisition training in context A on a first day, extinction training in a single context (B1) or in four different contexts (B1-B4) one day later, and fear and extinction recall and reinstatement in context B1 and a novel context C on a third day one week later. Multiple extinction contexts led to a stronger differential activation decrease in the hippocampus during extinction learning compared to a single extinction context. One week later, the multiple context group compared with the single context group showed reduced differential amygdala activation during fear renewal in the novel context C compared with the extinction context B1. Furthermore, multiple extinction contexts diminished amygdala activation during a subsequent reinstatement test in context B1. However, there were no significant differences in differential conditioned SCRs. These results indicate that the use of multiple extinction contexts during extinction training leads to reduced conditioned responses in the amygdala-hippocampus complex.
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Encéfalo/fisiologia , Extinção Psicológica/fisiologia , Medo/fisiologia , Rememoração Mental/fisiologia , Tonsila do Cerebelo/fisiologia , Mapeamento Encefálico , Giro do Cíngulo/fisiologia , Hipocampo/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/fisiologiaRESUMO
Motor imagery (MI) is the process in which subjects imagine executing a body movement with a strong kinesthetic component from a first-person perspective. The individual capacity to elicit such mental images is not universal but varies within and between subjects. Neuroimaging studies have shown that these inter-as well as intra-individual differences in imagery quality mediate the amplitude of neural activity during MI on a group level. However, these analyses were not sensitive to forms of representation that may not map onto a simple modulation of overall amplitude. Therefore, the present study asked how far the subjective impression of motor imagery vividness is reflected by a spatial neural code, and how patterns of neural activation in different motor regions relate to specific imagery impressions. During fMRI scanning, 20 volunteers imagined three different types of right-hand actions. After each imagery trial, subjects were asked to evaluate the perceived vividness of their imagery. A correlation analysis compared the rating differences and neural dissimilarity values of the rating groups separately for each region of interest. Results showed a significant positive correlation in the left vPMC and right IPL, indicating that these regions particularly reflect perceived imagery vividness in that similar rated trials evoke more similar neural patterns. A decoding analysis revealed that the vividness of the motor image related systematically to the action specificity of neural activation patterns in left vPMC and right SPL. Imagined actions accompanied by higher vividness ratings were significantly more distinguishable within these areas. Altogether, results showed that spatial patterns of neural activity within the human motor cortices reflect the individual vividness of imagined actions. Hence, the findings reveal a link between the subjective impression of motor imagery vividness and objective physiological markers.
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Imaginação/fisiologia , Cinestesia/fisiologia , Córtex Motor/fisiologia , Movimento , Lobo Parietal/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Individualidade , Imageamento por Ressonância Magnética , Masculino , Desempenho Psicomotor , Adulto JovemRESUMO
In communication, who is communicating can be just as important as what is said. However, sender identity in virtual communication is often inferred rather than perceived. Therefore, the present research investigates the brain structures activated by sender identity attributions and evaluative feedback processing during virtual communication. In a functional magnetic resonance imaging (fMRI) study, 32 participants were told that they would receive personality feedback, either sent from another human participant or from a randomly acting computer. In reality, both conditions contained random but counterbalanced feedback, automatically delivered by approving or denying negative, neutral, or positive adjectives. Although physically identical, feedback attributed to the "human" sender activated multiple regions within a "social brain" network, including the superior frontal, medial prefrontal, and orbitofrontal cortex, anterior and posterior parts of the cingulate cortex, and the bilateral insula. Regardless of attributed sender, positive feedback increased responses in the striatum and bilateral amygdalae, while negative compared to neutral feedback elicited stronger insula and somatosensory responses. These results reveal the recruitment of an extensive mentalizing and social brain network by mere sender attributions and the activation of brain structures related to reward and punishment by verbal feedback, demonstrating its embodied processing.
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Comunicação , Emoções/fisiologia , Lobo Frontal/fisiologia , Relações Interpessoais , Sistema Límbico/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Realidade Virtual , Adulto JovemRESUMO
Appetitive conditioning is considered a central mechanism for the vulnerability to psychiatric disorders. However, the investigation of individual differences that are related to altered appetitive learning has been almost neglected so far. The aim of this study was to investigate the link between neuroticism and appetitive conditioning processes. 79 subjects participated in a differential conditioning procedure in which a conditioned stimulus (CS+) was paired with a reward (money) after a fast behavioral response, while a second conditioned stimulus (CS-) was never followed by a reward, irrespective of the behavioral response. As a main result, neuroticism correlated negatively with the underlying neural processes of appetitive conditioning in females, but not in males. In detail, higher levels of neuroticism were associated with decreased neural responses in the left (pâ¯=â¯.001) and right amygdala (pâ¯=â¯.011), left (pâ¯=â¯.063) and right (pâ¯=â¯.019) nucleus accumbens, and left (pâ¯=â¯.002) and right (pâ¯=â¯.021) orbitofrontal cortex (all results are family-wise-error-corrected). The present results support previous findings, which also showed an inverse sex-specific effect in the context of neuroticism and emotional processing in females. In addition, the findings suggest that neuroticism is not solely linked to increased amygdala sensitivity during the processing of negative stimuli but also to decreased neural responses when processing rewarding stimuli. Possible explanations for the sex differences and implications are discussed.