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Premenstrual symptomatology is a widespread and yet under-researched problem. To date, there is no German instrument for assessing the broad spectrum of possible symptoms and their degree of expression. For this reason, the short versions of the Premenstrual Assessment Form with 20 and 10 items were translated and validated in a sample of N=147 menstruating persons. The internal consistencies of the 20-item and 10-item versions are high (Cronbach's αPAF20=0.93 and αPAF10=0.88, respectively) and comparable to the original versions. Factor analysis identified two scales that assess psychological and physiological symptoms. Convergent validity was demonstrated by a correlation with the PMS Impact Questionnaire (rPAF20=0.66, p<.001). This association was significantly higher (z=2.67, p=0.004) than the correlation with the Brief Symptom Inventory-18 (rPAF20=0.50, p<0.001), which verifies divergent validity. Additionally, cut-off values for suspected diagnoses based on DSM-V diagnostic criteria for both short forms were calculated. The translated Premenstrual Assessment Form is a valid, reliable, and parsimonious instrument that can be used flexibly. It is suitable for quantifying premenstrual symptomatology in research.
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Psicometría , Humanos , Encuestas y Cuestionarios , Reproducibilidad de los Resultados , Análisis Factorial , Manual Diagnóstico y Estadístico de los Trastornos MentalesRESUMEN
Emotional memories are better remembered than neutral ones, but the mechanisms leading to this memory bias are not well understood in humans yet. Based on animal research, it is suggested that the memory-enhancing effect of emotion is based on central noradrenergic release, which is triggered by afferent vagal nerve activation. To test the causal link between vagus nerve activation and emotional memory in humans, we applied continuous noninvasive transcutaneous auricular vagus nerve stimulation (taVNS) during exposure to emotional arousing and neutral scenes and tested subsequent, long-term recognition memory after 1 week. We found that taVNS, compared with sham, increased recollection-based memory performance for emotional, but not neutral, material. These findings were complemented by larger recollection-related brain potentials (parietal ERP Old/New effect) during retrieval of emotional scenes encoded under taVNS, compared with sham. Furthermore, brain potentials recorded during encoding also revealed that taVNS facilitated early attentional discrimination between emotional and neutral scenes. Extending animal research, our behavioral and neural findings confirm a modulatory influence of the vagus nerve in emotional memory formation in humans.SIGNIFICANCE STATEMENT Emotionally relevant information elicits stronger and more enduring memories than nonrelevant information. Animal research has shown that this memory-enhancing effect of emotion is related to the noradrenergic activation in the brain, which is triggered by afferent fibers of the vagus nerve (VN). In the current study, we show that noninvasive transcutaneous auricular VN stimulation enhances recollection-based memory formation specifically for emotionally relevant information as indicated by behavioral and electrophysiological indices. These human findings give novel insights into the mechanisms underlying the establishment of emotional episodic memories by confirming the causal link between the VN and memory formation which may help understand the neural mechanisms underlying disorders associated with altered memory functions and develop treatment options.
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Sistema Nervioso Autónomo/fisiología , Emociones/fisiología , Potenciales Evocados/fisiología , Memoria/fisiología , Nervio Vago/fisiología , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Reconocimiento en Psicología , Estimulación del Nervio Vago , Adulto JovenRESUMEN
Defensive behaviors in animals and humans vary dynamically with increasing proximity of a threat and depending upon the behavioral repertoire at hand. The current study investigated physiological and behavioral adjustments and associated brain activation when participants were exposed to dynamically approaching threat that was either inevitable or could be avoided by motor action. When the approaching threat was inevitable, attentive freezing was observed as indicated by fear bradycardia, startle potentiation, and a dynamic increase in activation of the anterior insula and the periaqueductal grey. In preparation for active avoidance a switch in defensive behavior was observed characterized by startle inhibition and heart rate acceleration along with potentiated activation of the amygdala and the periaqueductal grey. Importantly, the modulation of defensive behavior according to threat imminence and the behavioral option at hand was associated with activity changes in the ventromedial prefrontal cortex. These findings improve our understanding of brain mechanisms guiding human behavior during approaching threat depending on available resources.
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Reacción de Prevención/fisiología , Encéfalo/fisiología , Miedo/fisiología , Mapeo Encefálico/métodos , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Adulto JovenRESUMEN
Inhibitory learning is an important factor for decreasing fear expression. We investigated conditioned inhibition of learned fear responses using conditioned excitors and inhibitors differing in fear-relevance in a sample of 48 healthy female students. To study the effect of stimulus fear-relevance, we used the fear potentiated startle paradigm in an AX+/BX- discrimination learning task with fear-relevant (spider) vs. fear-irrelevant (butterfly) pictures as CS+ (A) and CS- (B), respectively. We found that, during acquisition, participants with elevated fear of spiders showed stronger fear potentiated startle to AX+ compared to BX- when the inhibitor (B) was fear-irrelevant (butterfly) using both median split as well as correlational analyses. In contrast, when the excitor (A) was fear-irrelevant (butterfly), fear potentiated startle to AX+ compared to BX- was reduced for participants with higher fear of spiders. Effects of conditioned inhibition were studied in a summation test, where excitor and inhibitor were presented in compound (AB) and compared to the last four excitor trials during prior acquisition. Conditioned inhibition was stronger for participants with a higher fear of spiders, when the butterfly acted as conditioned inhibitor (B). On the other hand, when the spider served as conditioned inhibitor, effects of conditioned inhibition were weaker for participants with higher fear of spiders. Hence, rather than to a general preparedness our data point to a specific impairment in safety learning for individually fear-relevant stimuli.
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Condicionamiento Psicológico/fisiología , Aprendizaje Discriminativo/fisiología , Miedo/psicología , Trastornos Fóbicos/psicología , Estimulación Acústica , Adolescente , Adulto , Miedo/fisiología , Femenino , Humanos , Inhibición Psicológica , Reflejo de Sobresalto/fisiología , Adulto JovenRESUMEN
The ability to associate neutral stimuli with motivationally relevant outcomes is an important survival strategy. In this study, we used event-related potentials (ERPs) to investigate brain dynamics of associative emotional learning when participants were confronted with multiple heterogeneous information. Participants viewed 144 different objects in the context of 144 different emotional and neutral background scenes. During each trial, neutral objects were shown in isolation and then paired with the background scene. All pairings were presented twice to compare ERPs in response to neutral objects before and after single association. After single pairing, neutral objects previously encoded in the context of emotional scenes evoked a larger P100 over occipital electrodes compared to objects that were previously paired with neutral scenes. Likewise, larger late positive potentials (LPPs) were observed over parieto-occipital electrodes (450-750 ms) for objects previously associated with emotional relative to neutral contexts. The LPP - but not P100 - enhancement was also related to subjective object/context binding. Taken together, our ERP data provide evidence for fast emotional associative learning, as reflected by heightened perceptual and sustained elaborative processing for neutral information previously encountered in emotional contexts. These findings could assist in understanding binding mechanisms in stress and anxiety, as well as in addiction and eating-related disorders.
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Aprendizaje por Asociación , Encéfalo/fisiología , Emociones , Potenciales Evocados , Femenino , Humanos , Masculino , Adulto JovenRESUMEN
There is abundant evidence in memory research that emotional stimuli are better remembered than neutral stimuli. However, effects of an emotionally charged context on memory for associated neutral elements is also important, particularly in trauma and stress-related disorders, where strong memories are often activated by neutral cues due to their emotional associations. In the present study, we used event-related potentials (ERPs) to investigate long-term recognition memory (1-week delay) for neutral objects that had been paired with emotionally arousing or neutral scenes during encoding. Context effects were clearly evident in the ERPs: An early frontal ERP old/new difference (300-500 ms) was enhanced for objects encoded in unpleasant compared to pleasant and neutral contexts; and a late central-parietal old/new difference (400-700 ms) was observed for objects paired with both pleasant and unpleasant contexts but not for items paired with neutral backgrounds. Interestingly, objects encoded in emotional contexts (and novel objects) also prompted an enhanced frontal early (180-220 ms) positivity compared to objects paired with neutral scenes indicating early perceptual significance. The present data suggest that emotional--particularly unpleasant--backgrounds strengthen memory for items encountered within these contexts and engage automatic and explicit recognition processes. These results could help in understanding binding mechanisms involved in the activation of trauma-related memories by neutral cues.
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Encéfalo/fisiología , Emociones/fisiología , Potenciales Evocados/fisiología , Memoria/fisiología , Reconocimiento en Psicología/fisiología , Adolescente , Adulto , Mapeo Encefálico/métodos , Electroencefalografía , Femenino , Humanos , Masculino , Estimulación Luminosa/métodos , Tiempo , Adulto JovenRESUMEN
INTRODUCTION: Most persons with an active menstrual cycle suffer from a range of aversive symptoms (e.g. reduced ability to concentrate) in the days before their menstruation - the premenstrual syndrome (PMS). Biological and cognitive mechanisms of PMS are poorly understood. It has been shown that vagally mediated heart rate variability (vmHRV), a physiological marker of self-regulation, decreases during the PMS-affected cycle phase (luteal phase) only in individuals with high PMS symptomology. This study investigates the specific associations between vmHRV, PMS symptomology and cognitive self-regulation (attentional control). METHODS: In this between-subject study, participants completed an vmHRV baseline measurement through electrocardiography, a reaction time paradigm to measure attentional control (modified attention network test revised, ANT-R) and filled out a questionnaire regarding impact of PMS as well as current menstrual phase. RESULTS: Mixed Model analysis showed interactions effects in the hypothesized direction. VmHRV was decreased during the luteal phase only in individuals with higher PMS. Analogously, performance in the Executive Functioning of the ANT-R task was reduced in the luteal compared to the follicular phase only in individuals with increased PMS symptoms. No effects were found in the Orienting Network Score. DISCUSSION: The results point in the direction of associations between vmHRV, PMS and self-regulation. This could hint at common underlying mechanisms. Further research, however, must be conducted to examine causal pathways to confirm these associations.
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Introduction: Heart rate variability biofeedback (HRVB) is a well-studied intervention known for its positive effects on emotional, cognitive, and physiological well-being, including relief from depressive symptoms. However, its practical use is hampered by high costs and a lack of trained professionals. Smartphone-based HRVB, which eliminates the need for external devices, offers a promising alternative, albeit with limited research. Additionally, premenstrual symptoms are highly prevalent among menstruating individuals, and there is a need for low-cost, accessible interventions with minimal side effects. With this pilot study, we aim to test, for the first time, the influence of smartphone-based HRVB on depressive and premenstrual symptoms, as well as anxiety/stress symptoms and attentional control. Methods: Twenty-seven participants with above-average premenstrual or depressive symptoms underwent a 4-week photoplethysmography smartphone-based HRVB intervention using a waitlist-control design. Laboratory sessions were conducted before and after the intervention, spaced exactly 4 weeks apart. Assessments included resting vagally mediated heart rate variability (vmHRV), attentional control via the revised attention network test (ANT-R), depressive symptoms assessed with the BDI-II questionnaire, and stress/anxiety symptoms measured using the DASS questionnaire. Premenstrual symptomatology was recorded through the PAF questionnaire if applicable. Data analysis employed linear mixed models. Results: We observed improvements in premenstrual, depressive, and anxiety/stress symptoms, as well as the Executive Functioning Score of the ANT-R during the intervention period but not during the waitlist phase. However, we did not find significant changes in vmHRV or the Orienting Score of the ANT-R. Discussion: These findings are promising, both in terms of the effectiveness of smartphone-based HRVB and its potential to alleviate premenstrual symptoms. Nevertheless, to provide a solid recommendation regarding the use of HRVB for improving premenstrual symptoms, further research with a larger sample size is needed to replicate these effects.
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Agorafobia/terapia , Frecuencia Cardíaca/fisiología , Terapia Implosiva/métodos , Evaluación de Resultado en la Atención de Salud/métodos , Trastorno de Pánico/terapia , Sistema Nervioso Parasimpático/fisiopatología , Cooperación del Paciente , Nervio Vago/fisiología , Agorafobia/fisiopatología , Electrocardiografía , Humanos , Trastorno de Pánico/fisiopatología , Pacientes Desistentes del TratamientoRESUMEN
Introduction: Vagally mediated heart rate variability is an index of autonomic nervous system activity that is associated with a large variety of outcome variables including psychopathology and self-regulation. While practicing heart rate variability biofeedback over several weeks has been reliably associated with a number of positive outcomes, its acute effects are not well known. As the strongest association with vagally mediated heart rate variability has been found particularly within the attention-related subdomain of self-regulation, we investigated the acute effect of heart rate variability biofeedback on attentional control using the revised Attention Network Test. Methods: Fifty-six participants were tested in two sessions. In one session each participant received a heart rate variability biofeedback intervention, and in the other session a control intervention of paced breathing at a normal ventilation rate. After the biofeedback or control intervention, participants completed the Attention Network Test using the Orienting Score as a measure of attentional control. Results: Mixed models revealed that higher resting baseline vagally mediated heart rate variability was associated with better performance in attentional control, which suggests more efficient direction of attention to target stimuli. There was no significant main effect of the intervention on attentional control. However, an interaction effect indicated better performance in attentional control after biofeedback in individuals who reported higher current stress levels. Discussion: The results point to acute beneficial effects of heart rate variability biofeedback on cognitive performance in highly stressed individuals. Although promising, the results need to be replicated in larger or more targeted samples in order to reach stronger conclusions about the effects.
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The startle response is a cross-species defensive reflex that is considered a key tool for cross-species translational emotion research. While the neural pathway mediating (affective) startle modulation has been extensively studied in rodents, human work on brain-behavior interactions has lagged in the past due to technical challenges, which have only recently been overcome through non-invasive simultaneous EMG-fMRI assessments. We illustrate key paradigms and methodological tools for startle response assessment in rodents and humans and review evidence for primary and modulatory neural circuits underlying startle responses and their affective modulation in humans. Based on this, we suggest a refined and integrative model for primary and modulatory startle response pathways in humans concluding that there is strong evidence from human work on the neurobiological pathway underlying the primary startle response while evidence for the modulatory pathway is still sparse. In addition, we provide methodological considerations to guide future work and provide an outlook on new and exciting perspectives enabled through technical and theoretical advances outlined in this work.
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Encéfalo , Reflejo de Sobresalto , Humanos , Reflejo de Sobresalto/fisiología , Electromiografía , Encéfalo/fisiología , Emociones/fisiologíaRESUMEN
The role of the human insula in facial emotion recognition is controversially discussed, especially in relation to lesion-location-dependent impairment following stroke. In addition, structural connectivity quantification of important white-matter tracts that link the insula to impairments in facial emotion recognition has not been investigated. In a case-control study, we investigated a group of 29 stroke patients in the chronic stage and 14 healthy age- and gender-matched controls. Lesion location of stroke patients was analysed with voxel-based lesion-symptom mapping. In addition, structural white-matter integrity for tracts between insula regions and their primarily known interconnected brain structures was quantified by tractography-based fractional anisotropy. Our behavioural analyses showed that stroke patients were impaired in the recognition of fearful, angry and happy but not disgusted expressions. Voxel-based lesion mapping revealed that especially lesions centred around the left anterior insula were associated with impaired recognition of emotional facial expressions. The structural integrity of insular white-matter connectivity was decreased for the left hemisphere and impaired recognition accuracy for angry and fearful expressions was associated with specific left-sided insular tracts. Taken together, these findings suggest that a multimodal investigation of structural alterations has the potential to deepen our understanding of emotion recognition impairments after stroke.
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Globally, armed conflicts have increased threefold since 2010. The number of children voluntarily engaging with armed groups is also rising, despite increasing efforts to prevent this grave human rights violation. However, traditional approaches focusing on the prevention, release, and reintegration of children through forced recruitment do not adequately address the complex and interlinking push and pull factors of voluntary recruitment. This qualitative study sought to deepen understanding of the drivers and consequences of voluntary recruitment from the perspectives of adolescents and their caregivers, as well as to explore how to better support families living in conflict settings. In-depth interviews were conducted with 74 adolescents (44 boys and 30 girls) ages 14 to 20 years and 39 caregivers (18 men and 21 women) ages 32 to 66 years in two distinct conflict settings: North Kivu, Democratic Republic of Congo and Ouham-Pendé, Central African Republic. Interviews with adolescents utilized a visual narrative technique. The findings examine the unique perspectives of adolescents engaged with armed groups and their caregivers to understand how conflict experiences, economic insecurity, and social insecurity influence adolescent's engagement with armed groups and reintegration with their families. The study found that families living in conflict settings are subject to traumatic experiences and economic hardship that erode protective family relationships, leaving adolescent boys and girls particularly vulnerable to the systemic and overlapping factors that influence them to engage with and return to armed groups. The findings illustrate how these factors can disrupt protective social structures, and inversely how familial support can act as a potential protective factor against recruitment and break the cycle of reengagement. By better understanding the experiences of adolescents enduring recruitment and how to support caregivers of those adolescents, more comprehensive programming models can be developed to adequately prevent voluntary recruitment and promote successful reintegration, enabling children to reach their full potential.
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The current study investigated the neural networks activated during the anticipation of potentially threatening body symptoms evoked by a guided hyperventilation task in a group of participants reporting either high or low fear of unexplained somatic sensations. 15 subjects reporting high and 14 subjects reporting low fear of somatic symptoms first learned that one of two cues predicted the occurrence of a hyperventilation task reliably producing body symptoms in all participants that were rated as more intense and unpleasant in the high fear group. During anticipation of unpleasant symptoms, high fear participants reported more intense body symptoms and showed potentiation of the startle reflex. After this learning session, participants were taken into the fMRI where the same cues either predicted the occurrence of hyperventilation or normoventilation, although the task was never performed in the scanner. During anticipation of hyperventilation all participants showed an increased activation of anterior insula/orbitofrontal cortex and rostral parts of the dorsal anterior cingulate cortex/dorsomedial prefrontal cortex (dACC/dmPFC). Brain activation of high compared to low fear participants differed in two ways. First, high fear participants showed an overall stronger activation of this network during threat and safe conditions indexing stronger anxious apprehension during the entire context. Second, while low fear participants no longer responded with stronger activation to the threat cue after experiencing that the hyperventilation challenge did not follow this cue, high fear participants continued to show stronger activation of the network to this cue. Activation of the rostral dACC/dmPFC was significantly correlated with reported fear of somatic symptoms. These data demonstrate that anticipation of interoceptive threat activates the same network that has been found to be active during anticipation of exteroceptive threat cues. Thus, the current paradigm might provide an innovative method to study anxious apprehension and treatment effects in patients with panic disorder.
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Anticipación Psicológica/fisiología , Encéfalo/fisiología , Señales (Psicología) , Miedo/fisiología , Vías Nerviosas/fisiología , Adolescente , Adulto , Mapeo Encefálico , Femenino , Humanos , Hiperventilación/complicaciones , Hiperventilación/fisiopatología , Interpretación de Imagen Asistida por Computador , Imagen por Resonancia Magnética , Masculino , Adulto JovenRESUMEN
Keeping aware of the locations of objects while one is moving requires the updating of spatial representations. As long as the objects are visible, attentional tracking is sufficient, but knowing where objects out of view went in relation to one's own body involves an updating of spatial working memory. Here, multiple object tracking was employed to study spatial updating and its neural correlates. In a dynamic 3D-scene, targets moved among visually indistinguishable distractors. The targets and distractors either stayed visible during continuous viewpoint changes or they turned invisible. The parametric variation of tracking load revealed load-dependent activations of the intraparietal sulcus, the superior parietal lobule, and the lateral occipital cortex in response to the attentive tracking task. Viewpoint changes with invisible objects that demanded retention and updating produced load-dependent activation only in the precuneus in line with its presumed involvement in updating spatial working memory.
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Atención/fisiología , Encéfalo/fisiología , Percepción de Movimiento/fisiología , Percepción Espacial/fisiología , Adulto , Femenino , Neuroimagen Funcional , Humanos , Imagen por Resonancia Magnética , Masculino , Memoria a Corto Plazo/fisiología , Lóbulo Parietal/fisiología , Estimulación LuminosaRESUMEN
Individuals who score high in self-reported Intolerance of Uncertainty (IU) tend to find uncertainty aversive. Prior research has demonstrated that under uncertainty individuals with high IU display difficulties in updating learned threat associations to safety associations. Importantly, recent research has shown that providing contingency instructions about threat and safety contingencies (i.e. reducing uncertainty) to individuals with high IU promotes the updating of learned threat associations to safety associations. Here we aimed to conceptually replicate IU and contingency instruction-based effects by conducting a secondary analysis of self-reported IU, ratings, skin conductance, and functional magnetic resonance imaging (fMRI) data recorded during uninstructed/instructed blocks of threat acquisition and threat extinction training (n = 48). Generally, no significant associations were observed between self-reported IU and differential responding to learned threat and safety cues for any measure during uninstructed/instructed blocks of threat acquisition and threat extinction training. There was some tentative evidence that higher IU was associated with greater ratings of unpleasantness and arousal to the safety cue after the experiment and greater skin conductance response to the safety cue during extinction generally. Potential explanations for these null effects and directions for future research are discussed.
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Señales (Psicología) , Respuesta Galvánica de la Piel , Afecto , Nivel de Alerta , Extinción Psicológica/fisiología , Humanos , IncertidumbreRESUMEN
Classical views suggest that experienced affect is related to a specific bodily response, whereas recent perspectives challenge this view postulating that similar affective experiences rather evoke different physiological responses. To further advance this debate in the field, we used representational similarity analysis to investigate the correspondence between subjective affect (arousal and valence ratings) and physiological reactions (skin conductance response [SCR], startle blink response, heart rate, and corrugator activity) across various emotion induction contexts (picture viewing task, sound listening task, and imagery task). Significant similarities were exclusively observed between SCR and arousal in the picture viewing task. However, none of the other physiological measures showed a significant relation with valence and arousal ratings in any of the tasks. These findings are discussed within the framework of the Populations hypothesis, suggesting that physiological responses do not depend on the experienced affect but are directly associated with the context in which they are evoked.
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Afecto , Nivel de Alerta , Afecto/fisiología , Nivel de Alerta/fisiología , Parpadeo , Emociones/fisiología , Respuesta Galvánica de la Piel , Humanos , Reflejo de Sobresalto/fisiologíaRESUMEN
The Covid-19 pandemic imposed new constraints on empirical research and forced researchers to transfer from traditional laboratory research to the online environment. This study tested the validity of a web-based episodic memory paradigm by comparing participants' memory performance for trustworthy and untrustworthy facial stimuli in a supervised laboratory setting and an unsupervised web setting. Consistent with previous results, we observed enhanced episodic memory for untrustworthy compared to trustworthy faces. Most importantly, this memory bias was comparable in the online and the laboratory experiment, suggesting that web-based procedures are a promising tool for memory research.
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COVID-19/epidemiología , Expresión Facial , Internet/estadística & datos numéricos , Memoria Episódica , Recuerdo Mental/fisiología , Reconocimiento en Psicología , Confianza , Adulto , COVID-19/psicología , COVID-19/virología , Femenino , Alemania/epidemiología , Humanos , Masculino , SARS-CoV-2/aislamiento & purificación , Adulto JovenRESUMEN
The theory of constructed emotions suggests that different psychological components, including core affect (mental and neural representations of bodily changes), and conceptualization (meaning-making based on prior experiences and semantic knowledge), are involved in the formation of emotions. However, little is known about their role in experiencing emotions. In the current study, we investigated how individual differences in interoceptive sensibility and emotional conceptualization (as potential correlates of these components) interact to moderate three important aspects of emotional experiences: emotional intensity (strength of emotion felt), arousal (degree of activation), and granularity (ability to differentiate emotions with precision). To this end, participants completed a series of questionnaires assessing interoceptive sensibility and emotional conceptualization and underwent two emotion experience tasks, which included standardized material (emotion differentiation task; ED task) and self-experienced episodes (day reconstruction method; DRM). Correlational analysis showed that individual differences in interoceptive sensibility and emotional conceptualization were related to each other. Principal Component Analysis (PCA) revealed two independent factors that were referred to as sensibility and monitoring. The Sensibility factor, interpreted as beliefs about the accuracy of an individual in detecting internal physiological and emotional states, predicted higher granularity for negative words. The Monitoring factor, interpreted as the tendency to focus on the internal states of an individual, was negatively related to emotional granularity and intensity. Additionally, Sensibility scores were more strongly associated with greater well-being and adaptability measures than Monitoring scores. Our results indicate that independent processes underlying individual differences in interoceptive sensibility and emotional conceptualization contribute to emotion experiencing.
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During fear conditioning, a cue (CS) signals an inevitable distal threat (US) and evokes a conditioned response that can be described as attentive immobility (freezing). The organism remains motionless and monitors the source of danger while startle responses are potentiated, indicating a state of defensive hypervigilance. Although in animals vagally mediated fear bradycardia is also reliably observed under such circumstances, results are mixed in human fear conditioning. Using a single-cue fear conditioning and extinction protocol, we tested cardiac reactivity and startle potentiation indexing low-level defensive strategies in a fear-conditioned (n = 40; paired presentations of CS and US) compared with a non-conditioned control group (n = 40; unpaired presentations of CS and US). Additionally, we assessed shock expectancy ratings on a trial-by-trial basis indexing declarative knowledge of the previous contingencies. Half of each group underwent extinction under sham or active transcutaneous vagus nerve stimulation (tVNS), serving as additional proof of concept. We found stronger cardiac deceleration during CS presentation in the fear learning relative to the control group. This learned fear bradycardia was positively correlated with conditioned startle potentiation but not with declarative knowledge of CS-US contingencies. TVNS abolished differences in heart rate changes between both groups and removed the significant correlation between late cardiac deceleration and startle potentiation in the fear learning group. Results suggest, fear-conditioned cues evoke attentive immobility in humans, characterized by cardiac deceleration and startle potentiation. Such defensive response pattern is elicited by cues predicting inevitable distal threat and resembles conditioned fear responses observed in rodents.