Aversive conditioning has been proposed as an important factor involved in the etiology of posttraumatic stress disorder (PTSD). However, it is not yet fully understood exactly which learning ...mechanisms are characteristic for PTSD.
PTSD patients (n=36), and healthy individuals with and without trauma exposure (TE group, n=21; nTE group, n=34), underwent a differential fear conditioning experiment consisting of habituation, acquisition, and extinction phases. An electrical stimulus served as the unconditioned stimulus (US), and two neutral pictures as conditioned stimuli (CS+, paired; CS-, unpaired). Conditioned responses were quantified by skin conductance responses (SCRs), subjective ratings of CS valence and US-expectancy, and a behavioural test.
In contrast to the nTE group, PTSD patients showed delayed extinction of SCRs to the CS+. Online ratings of valence and US-expectancy as well as the behavioural test confirmed this pattern. These findings point to a deficit in extinction learning and highlight the role of affective valence appraisals and cognitive biases in PTSD. In addition, there was some evidence that a subgroup of PTSD patients had difficulties in learning the CS–US contingency, thereby providing preliminary evidence of reduced discrimination learning.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
When we become engrossed in novels, films, games, or even our own wandering thoughts, we can feel present in a reality distinct from the real world. Although this subjective sense of presence is, ...presumably, a ubiquitous aspect of conscious experience, the mechanisms that produce it are unknown. Correlational studies conducted in virtual reality have shown that we feel more present when we are afraid, motivating claims that physiological changes contribute to presence; however, such causal claims remain to be evaluated. Here, we report two experiments that test the causal role of subjective and physiological components of fear (i.e., activation of the sympathetic nervous system) in generating presence. In Study 1, we validated a virtual reality simulation capable of inducing fear. Participants rated their emotions while they crossed a wooden plank that appeared to be suspended above a city street; at the same time, we recorded heart rate and skin conductance levels. Height exposure increased ratings of fear, presence, and both measures of sympathetic activation. Although presence and fear ratings were correlated during height exposure, presence and sympathetic activation were unrelated. In Study 2, we manipulated whether the plank appeared at height or at ground level. We also captured participants' movements, which revealed that alongside increases in subjective fear, presence, and sympathetic activation, participants also moved more slowly at height relative to controls. Using a mediational approach, we found that the relationship between height exposure and presence on the plank was fully mediated by self-reported fear, and not by sympathetic activation.
Public Significance StatementPresence is the feeling of being physically situated in the world. Previous studies report that people are more "present" when experiencing intense emotions. We used a fear-inducing virtual reality simulation to show that presence is related to the feeling of fear, but not to the increases in heart rate or sweating that accompany it. Our findings help us to understand how the mind and body make us feel present.
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CEKLJ, FFLJ, NUK, ODKLJ, PEFLJ, UPUK
Pharmacotherapy is often used to target symptoms of posttraumatic stress disorder (PTSD), but does not provide definitive treatment, and side effects of daily medication are often problematic. ...Trauma-focused psychotherapies are more likely than drug treatment to achieve PTSD remission, but have high dropout rates and ineffective for a large percentage of patients. Therefore, research into drugs that might increase the effectiveness of psychotherapy is a logical avenue of investigation. The most promising drug studied as a catalyst to psychotherapy for PTSD thus far is 3,4-methylenedioxymethamphetamine (MDMA), commonly known as the recreational drug “Ecstasy.” MDMA stimulates the release of hormones and neurochemicals that affect key brain areas for emotion and memory processing. A series of recently completed phase 2 clinical trials of MDMA-assisted psychotherapy for treatment of PTSD show favorable safety outcomes and large effect sizes that warrant expansion into multi-site phase 3 trials, set to commence in 2018. The nonprofit sponsor of the MDMA drug development program, the Multidisciplinary Association for Psychedelic Studies (MAPS), is supporting these trials to explore whether MDMA, administered on only a few occasions, can increase the effectiveness of psychotherapy. Brain imaging techniques and animal models of fear extinction are elucidating neural mechanisms underlying the robust effects of MDMA on psychological processing; however, much remains to be learned about the complexities of MDMA effects as well as the complexities of PTSD itself.
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DOBA, EMUNI, FIS, FSPLJ, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, VSZLJ, ZAGLJ
Background Mild traumatic brain injury (cerebral concussion) results in cognitive and emotional dysfunction. These injuries are a significant risk factor for the development of anxiety disorders, ...including posttraumatic stress disorder. However, because physically traumatic events typically occur in a highly emotional context, it is unknown whether traumatic brain injury itself is a cause of augmented fear and anxiety. Methods Rats were trained with one of five fear-conditioning procedures ( n = 105) 2 days after concussive brain trauma. Fear learning was assessed over subsequent days and chronic changes in fear learning and memory circuitry were assessed by measuring N -methyl-D-aspartate receptor subunits and glutamic acid decarboxylase, 67 kDa isoform protein levels in the hippocampus and basolateral amygdala complex (BLA). Results Injured rats exhibited an overall increase in fear conditioning, regardless of whether fear was retrieved via discrete or contextual-spatial stimuli. Moreover, injured rats appeared to overgeneralize learned fear to both conditioned and novel stimuli. Although no gross histopathology was evident, injury resulted in a significant upregulation of excitatory N -methyl-D-aspartate receptors in the BLA. There was a trend toward decreased γ-aminobutyric acid-related inhibition (glutamic acid decarboxylase, 67 kDa isoform) in the BLA and hippocampus. Conclusions These results suggest that mild traumatic brain injury predisposes the brain toward heightened fear learning during stressful postinjury events and provides a potential molecular mechanism by which this occurs. Furthermore, these data represent a novel rodent model that can help advance the neurobiological and therapeutic understanding of the comorbidity of posttraumatic stress disorder and traumatic brain injury.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
In the present work we have studied a prey-predator model with logistic growth of the prey in the absence of the predator. We have also considered the fear effect and have investigated the impact of ...fear of the predator on prey when the predator is provided additional food. Functional responses of the predator towards prey and additional food are derived in this text. Death rates of both prey and predator have been considered as stochastic parameters due to the effect of the fluctuating environment. Existence and uniqueness, boundedness and uniform continuity of the global positive solution of the proposed model have been established. The conditions for extinction and persistence of the system have been derived. In the investigation, it is found that environmental noise plays a vital role in extinction as well as in persistence. Our analytical derivations are justified through numerical simulations which show the reliability of the model from the ecological point of view. We have also investigated the impact of intense fear as well as the absence of fear on this model by numerical simulation. Several interesting numerical results have been obtained based on different fear functions.
The current study was conducted to investigate the association between the resilience of the adults affected by the Covid-19 pandemic and Covid-19 fear, meaning in life, life satisfaction, ...intolerance of uncertainty, hope gender, psychological trauma history and the presence of the individuals diagnosed with Covid-19 around. A total of 929 adults with the mean age of 41.58 participated in the current study. Findings from the study indicated that hope, meaning in life, life satisfaction, not having the experience of psychological trauma positively and significantly predict resilience while intolerance of uncertainty and Covid-19 fear negatively and significantly predict resilience. The presence of people diagnosed with Covid-19 and gender on the other hand were found to not significantly predict resilience.
•The model constructed for the regression seems to be significant on resilience in adults.•Hope and intolerance of uncertainty are the most predictive variables of resilience.•Meaning in life, Covid-19 fear and life satisfaction are predictive of resilience.•Psychological trauma history is predictive of resilience.•Other variables aren't significant predictors of resilience in current study.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The effect of Fear of Falling (FOF) and fear-related Activity Restriction (AR) on Late Life Depression (LLD) remains unstudied in older adults. In this study, we aimed to clarify associations between ...FOF, AR and the prevalence and incidence of LLD in a large cohort of community-dwelling older adults.
In this prospective study, participants (n = 4230; 52.1% female) aged ≥50 years completed the survey on whether they had FOF and AR at baseline. In addition, the Centre for Epidemiological Studies Depression (CESD) scale was used to evaluate LLD at baseline and after 2 years of follow-up. Moreover, LLD was defined by a CES-D score ≥ 16, at follow-up.
The results showed that the prevalence and incidence of LLD were 6.9% (n = 293) and 4.2% (n = 167), respectively. In addition, most of the respondents with LLD were female (64.9% vs 55.4%) and 50–59 years of age (50.9% vs 42.8%, all P < 0.05). Analysis of data from Wave 1 and 2 using logistic regression also demonstrated that the levels of FOF/AR was associated with 82.2% and 62.7% higher odds of prevalence OR = 1.822, 95%CI: 1.272–2.612 and incidence OR = 1.627, 95%CI: 1.085–2.440 of LLD, respectively in the fully adjusted models.
FOF and AR may be associated with the prevalence and incidence of LLD. Additionally, the study highlighted the importance of assessing LLD in older adults with FOF and AR.
•FOF, AR and LLD were assessed in a representative Irish community sample.•FOF/AR was independently associated with the prevalence and incidence of LLD.•FOF/AR may represent potentially modifiable risk factors for LLD.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Manipulations that increase dopamine (DA) signaling can enhance fear extinction, but the circuits involved remain unknown. DA neurons originating in the substantia nigra (SN) projecting to the dorsal ...striatum (DS) are traditionally viewed in the context of motor behavior, but growing data implicate this nigrostriatal circuit in emotion. Here we investigated the role of nigrostriatal DA in fear extinction. Activation of SN DA neurons with designer G
-coupled receptors exclusively activated by designer drugs (G
-DREADD) during fear extinction had no effect on fear extinction acquisition, but enhanced fear extinction memory and blocked the renewal of fear in a novel context; a pattern of data paralleled by cFos expression in the central amygdala. D1 receptors in the DS are a likely target mediating the effects of SN DA activation. D1-expressing neurons in the medial DS (DMS) were recruited during fear extinction, and G
-DREADD-induced DA potentiated activity of D1-expressing neurons in both the DMS and the lateral DS (DLS). Pharmacological activation of D1 receptors in the DS did not impact fear extinction acquisition or memory, but blocked fear renewal in a novel context. These data suggest that activation of SN DA neurons and DS D1 receptors during fear extinction render fear extinction memory resistant to the disrupting effects of changes in contextual contingencies, perhaps by recruiting habitual learning strategies involving the DLS. Nigrostriatal DA thus represents a novel target to enhance long-term efficacy of extinction-based therapies for anxiety and trauma-related disorders.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Background & Purpose: Organizational fear has a negative impact on the employee performance at work, creates a silent culture, delays decision-making, and prevents innovation and development in the ...organization. The aim of this research is to provide a comprehensive model of fear management in financial organizations.Methodology: To obtain the main purpose of the study, grounded theory method was used. Participants of the study were experts in public and private organizations in financial industry that are active in Tehran, from which 20 experts were selected as a statistical sample through a purposeful sampling method.Findings: Based on the results, the central category was explained in three subcategories of communication, functional and motivational dimensions. Causal conditions were classified in the form of 2 categories of intra and extra-organizational factors, background conditions in the form of two categories of social and technological background, and intervening conditions in the form of two categories of economic conditions of society and psychological conditions triggering organizational fear. Actions-reactions were identified in the form of four categories of managing the roots of fear in employees, human resources management measures, behavioral reforms, and cultural measures. Finally, the consequences were explained in four categories of functional, behavioral, structural, and social damages.Conclusion: Using this model, managers can take steps in the field of understanding the organizational fear of employees, and in order to prevent or treat it, they can also take measures to identify and define the factors that cause fear, and finally in order to deal with organizational fear, they can reform the structure and culture.
The aim of this study is to determine the anxiety and fear related to coronavirus disease 2019 (COVID-19) and their associations with travel, tourism and hospitality, in the Portuguese population. ...The Coronavirus Anxiety Scale (CAS) and Fear of COVID-19 Scale (FCV-19S) were validated for the Portuguese population and correlations with issues related to travel, tourism and hospitality were established. CAS and FCV-19S presented a good adjustment model and solid reliability and validity. Correlations between CAS and FCV-19S and the perception of the impact of COVID-19 in travel, tourism and hospitality were found. Participants considered that COVID-19 mainly affected their holidays and leisure time. However, the strongest correlation established was between total FCV-19S and emotional fear FCV-19S and the fear of attending hotel facilities. The Portuguese versions of CAS and FCV-19S are reliable psychological tools to assess anxiety and fear in relation to COVID-19 for the general population. The use of hotel facilities is the most threatening issue related to travel, tourism and hospitality. The results suggest that hotels should invest in hygiene and safety measures that allow users to regain confidence in hotel equipment.
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