Graded Exposure Therapy for Fear Avoidance Behaviour After Concussion (GET FAB): protocol for a multisite Canadian randomised controlled trial.

INTRODUCTION: Persistent symptoms after mild traumatic brain injury (mTBI) negatively affect daily functioning and quality of life. Fear avoidance behaviour, a coping style in which people avoid or escape from activities or situations that they expect will exacerbate their symptoms, maybe a particularly potent and modifiable risk factor for chronic disability after mTBI. This study will evaluate the efficacy of graded exposure therapy (GET) for reducing persistent symptoms following mTBI, with two primary aims: (1) To determine whether GET is more effective than usual care; (2) to identify for whom GET is the most effective treatment option, by evaluating whether baseline fear avoidance moderates differences between GET and an active comparator (prescribed aerobic exercise). Our findings will guide evidence-based care after mTBI and enable better matching of mTBI patients to treatments. METHODS AND ANALYSIS: We will conduct a multisite randomised controlled trial with three arms. Participants (n=220) will be recruited from concussion clinics and emergency departments in three Canadian provinces and randomly assigned (1:2:2 ratio) to receive enhanced usual care, GET or prescribed aerobic exercise. The outcome assessment will occur remotely 14-18 weeks following baseline assessment, after completing the 12-week treatment phase. The primary outcome will be symptom severity (Rivermead Post-concussion Symptoms Questionnaire). ETHICS AND DISSEMINATION: Informed consent will be obtained from all participants. All study procedures were approved by the local research ethics boards (University of British Columbia Clinical Research Ethics Board, University of Calgary Conjoint Health Research Ethics Board, University Health Network Research Ethics Board-Panel D). Operational approvals were obtained for Vancouver Coastal Health Research Institute and Provincial Health Services Authority. If GET proves effective, we will disseminate the GET treatment manual and present instructional workshops for clinicians. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov #NCT05365776.

Central amygdala CRF+ neurons promote heightened threat reactivity following early life adversity in mice.

Failure to appropriately predict and titrate reactivity to threat is a core feature of fear and anxiety-related disorders and is common following early life adversity (ELA). A population of neurons in the lateral central amygdala (CeAL) expressing corticotropin releasing factor (CRF) have been proposed to be key in processing threat of different intensities to mediate active fear expression. Here, we use in vivo fiber photometry to show that ELA results in sex-specific changes in the activity of CeAL CRF+ neurons, yielding divergent mechanisms underlying the augmented startle in ELA mice, a translationally relevant behavior indicative of heightened threat reactivity and hypervigilance. Further, chemogenic inhibition of CeAL CRF+ neurons selectively diminishes startle and produces a long-lasting suppression of threat reactivity. These findings identify a mechanism for sex-differences in susceptibility for anxiety following ELA and have broad implications for understanding the neural circuitry that encodes and gates the behavioral expression of fear.

Disengagement of somatostatin neurons from lateral septum circuitry by oxytocin and vasopressin restores social-fear extinction and suppresses aggression outbursts in Prader-Willi syndrome model.

Background: Responding to social signals by expressing the correct behavior is not only challenged in autism, but also in diseases with high prevalence of autism, like Prader-Willi Syndrome (PWS). Clinical evidence suggests aberrant pro-social behavior in patients can be regulated by intranasal oxytocin (OXT) or vasopressin (AVP). However, what neuronal mechanisms underlie impaired behavioral responses in a socially-aversive context, and how can they be corrected, remains largely unknown. Methods: Using the Magel2 knocked-out (KO) mouse model of PWS (crossed with CRE-dependent transgenic lines), we devised optogenetic, physiological and pharmacological strategies in a social-fear-conditioning paradigm. Pathway specific roles of OXT and AVP signaling were investigated converging on the lateral septum (LS), a region which receives dense hypothalamic inputs. Results: OXT and AVP signaling promoted inhibitory synaptic transmission in the LS, which failure in Magel2KO mice disinhibited somatostatin (SST) neurons and disrupted social-fear extinction. The source of OXT and AVP deficits mapped specifically in the supraoptic nucleus→LS pathway of Magel2KO mice disrupting social-fear extinction, which could be corrected by optogenetic or pharmacological inhibition of SST-neurons in the LS. Interestingly, LS SST-neurons also gated the expression of aggressive behavior, possibly as part of functional units operating beyond local septal circuits. Conclusions: SST cells in the LS play a crucial role in integration and expression of disrupted neuropeptide signals in autism, thereby altering the balance in expression of safety versus fear. Our results uncover novel mechanisms underlying dysfunction in a socially-aversive context, and provides a new framework for future treatments in autism-spectrum disorders.

Zona incerta mediates early life isoflurane-induced fear memory deficits.

The potential long-term effects of anesthesia on cognitive development, especially in neonates and infants, have raised concerns. However, our understanding of its underlying mechanisms and effective treatments is still limited. In this study, we found that early exposure to isoflurane (ISO) impaired fear memory retrieval, which was reversed by dexmedetomidine (DEX) pre-treatment. Measurement of c-fos expression revealed that ISO exposure significantly increased neuronal activation in the zona incerta (ZI). Fiber photometry recording showed that ZI neurons from ISO mice displayed enhanced calcium activity during retrieval of fear memory compared to the control group, while DEX treatment reduced this enhanced calcium activity. Chemogenetic inhibition of ZI neurons effectively rescued the impairments caused by ISO exposure. These findings suggest that the ZI may play a pivotal role in mediating the cognitive effects of anesthetics, offering a potential therapeutic target for preventing anesthesia-related cognitive impairments.

The emotional states and associated behavioral responses (flexible-adaptive behaviors vs. inflexible-maladaptive behaviors) of cancer patients during the SARS-CoV-2 outbreak: A multi-center cross-sectional study in Italy.

OBJECTIVE: Distress during SARS-CoV-2 outbreak affected also cancer patients' well-being. Aim of this study was to investigate patient' reactions and behavior (flexible-adaptive vs. inflexible-maladaptive) during the SARS-CoV-2 outbreak. METHODS: A cross-sectional survey was designed with a self-report questionnaire, "the ImpACT questionnaire," developed for the study. Regression analysis was performed on data. RESULTS: Four hundred and forty five cancer patients from 17 Italian regions participated in the study. 79.8% of participants were female (mean age of 58 years). 92.6% of participants reported feeling vulnerable to COVID-19 contagion; 75.6% reported helpless, 62.7% sad, 60.4% anxious, and 52.0% anger. Avoidance of thinking about coronavirus is the principal maladaptive behavior that emerged. Participants who reported feeling anxious were more likely to have fear of staff being infected with COVID-19 (OR = 3.01; 95% CI = 1.49-6.30) and to have disrupted sleep due to worry (OR = 2.42; 95% CI = 1.23-4.83). Younger participants reported more anxiety (OR = 0.97; 95% CI = 0.94-1.00); men reported feeling calm more than women (OR = 2.60; 95% CI = 1.27-5.43). CONCLUSIONS: Majority of cancer patients reported serious concerns regarding SARS-CoV-2 infection; reliable information and psychological support must be offers to respond to these needs.

Dominant activities of fear engram cells in the dorsal dentate gyrus underlie fear generalization in mice.

Over-generalized fear is a maladaptive response to harmless stimuli or situations characteristic of posttraumatic stress disorder (PTSD) and other anxiety disorders. The dorsal dentate gyrus (dDG) contains engram cells that play a crucial role in accurate memory retrieval. However, the coordination mechanism of neuronal subpopulations within the dDG network during fear generalization is not well understood. Here, with the Tet-off system combined with immunostaining and two-photon calcium imaging, we report that dDG fear engram cells labeled in the conditioned context constitutes a significantly higher proportion of dDG neurons activated in a similar context where mice show generalized fear. The activation of these dDG fear engram cells encoding the conditioned context is both sufficient and necessary for inducing fear generalization in the similar context. Activities of mossy cells in the ventral dentate gyrus (vMCs) are significantly suppressed in mice showing fear generalization in a similar context, and activating the vMCs-dDG pathway suppresses generalized but not conditioned fear. Finally, modifying fear memory engrams in the dDG with "safety" signals effectively rescues fear generalization. These findings reveal that the competitive advantage of dDG engram cells underlies fear generalization, which can be rescued by activating the vMCs-dDG pathway or modifying fear memory engrams, and provide novel insights into the dDG network as the neuronal basis of fear generalization.

"Nobody Here Likes Her"-The Impact of Parental Verbal Threat Information on Children's Fear of Strangers.

Parental verbal threat (vs. safety) information about strangers may induce fears of these strangers in adolescents. In this multi-method experimental study, utilizing a within-subject design, parents provided standardized verbal threat or safety information to their offspring (N = 77, Mage = 11.62 years, 42 girls) regarding two strangers in the lab. We also explored whether the impact of parental verbal threat information differs depending on the social anxiety levels of parents or fearful temperaments of adolescents. Adolescent's fear of strangers during social interaction tasks was assessed using cognitive (fear beliefs, attention bias), behavioral (observed avoidance and anxiety), and physiological (heart rate) indices. We also explored whether the impact of parental verbal threat information differs depending on the social anxiety levels of parents or fearful temperaments of adolescents. The findings suggest that a single exposure to parental verbal threat (vs. safety) information increased adolescent's self-reported fears about the strangers but did not increase their fearful behaviors, heart rate, or attentional bias. Furthermore, adolescents of parents with higher social anxiety levels or adolescents with fearful temperaments were not more strongly impacted by parental verbal threat information. Longitudinal research and studies investigating parents' naturalistic verbal expressions of threat are needed to expand our understanding of this potential verbal fear-learning pathway.

Predictive Model of the Relationship between Appearance, Eating Attitudes, and Physical Activity Behavior in Young People amid COVID-19.

This cross-sectional study conducted in Poland explored the relationship between the fear of negative appearance evaluations, eating disorders, and physical activity objectives, particularly during the COVID-19 pandemic. The Fear of Negative Appearance Evaluation Scale (FNAES), the Eating Attitude Test (EAT-26), and the Physical Activity Goals Inventory (IPAO) were administered to 644 participants (455 males with a mean age of 35.2 ± 6.2 years and 189 females with a mean age of 30.18 ± 5.7 years). This study explored the effects of gender, age, and body mass index (BMI) on FNAES, EAT-26, and IPAO scores. The results of this study demonstrated that females scored higher on fear of negative appearance, peaking at 41-50 years of age. Distinct BMI categories were associated with different negative appearance fear scores, eating attitudes, and physical activity objectives. Significant correlations were also found between the fear of negative appearance, dietary attitudes, and physical activity goals. Eating attitudes completely moderated the relationship between the fear of negative appearance and physical activity objectives. A significant interaction effect of age and body mass index on physical activity objectives was also revealed. These results highlight the relevance of considering gender, age, and body mass index when examining the associations between the fear of negative appearance, eating attitudes, and physical activity objectives.

Reducing FKBP51 Expression in the Ventral Hippocampus Decreases Auditory Fear Conditioning in Male Rats.

Fear conditioning evokes a physiologic release of glucocorticoids that assists learning. As a cochaperone in the glucocorticoid receptor complex, FKBP51 modulates stress-induced glucocorticoid signaling and may influence conditioned fear responses. This study combines molecular and behavioral approaches to examine whether locally reducing FKBP51 expression in the ventral hippocampus is sufficient to affect fear-related behaviors. We hypothesized that reducing FKBP51 expression in the VH would increase glucocorticoid signaling to alter auditory fear conditioning. Adult male rats were injected with an adeno-associated virus (AAV) vector expressing short hairpin - RNAs (shRNA) targeting FKBP5 into the ventral hippocampus to reduce FKBP5 levels or a control AAV. Infusion of FKBP5-shRNA into the ventral hippocampus decreased auditory fear acquisition and recall. Although animals injected with FKBP5-shRNA showed less freezing during extinction recall, the difference was due to a reduced fear recall rather than improved extinction. Reducing ventral hippocampus FKBP51 did not affect exploratory behavior in either the open field test or the elevated zero maze test but did increase passive behavior in the forced swim test, suggesting that the reduction in auditory fear recall was not due to more active responses to acute stress. Furthermore, lower ventral hippocampus FKBP51 levels did not alter corticosterone release in response to restraint stress, suggesting that the reduced fear recall was not due to lower corticosterone release. Our findings suggest FKBP51 in the ventral hippocampus plays a selective role in modulating fear-learning processes and passive behavioral responses to acute stress rather than hypothalamic-pituitary-adrenal axis reactivity or exploratory responses.

Interaction between the prefrontal and visual cortices supports subjective fear.

It has been reported that threatening and non-threatening visual stimuli can be distinguished based on the multi-voxel patterns of haemodynamic activity in the human ventral visual stream. Do these findings mean that there may be evolutionarily hardwired mechanisms within early perception, for the fast and automatic detection of threat, and maybe even for the generation of the subjective experience of fear? In this human neuroimaging study, we presented participants ('fear' group: N = 30; 'no fear' group: N = 30) with 2700 images of animals that could trigger subjective fear or not as a function of the individual's idiosyncratic 'fear profiles' (i.e. fear ratings of animals reported by a given participant). We provide evidence that the ventral visual stream may represent affectively neutral visual features that are statistically associated with fear ratings of participants, without representing the subjective experience of fear itself. More specifically, we show that patterns of haemodynamic activity predictive of a specific 'fear profile' can be observed in the ventral visual stream whether a participant reports being afraid of the stimuli or not. Further, we found that the multivariate information synchronization between ventral visual areas and prefrontal regions distinguished participants who reported being subjectively afraid of the stimuli from those who did not. Together, these findings support the view that the subjective experience of fear may depend on the relevant visual information triggering implicit metacognitive mechanisms in the prefrontal cortex. This article is part of the theme issue 'Sensing and feeling: an integrative approach to sensory processing and emotional experience'.

Engrams: From Behavior to Brain-Wide Networks.

Animals utilize a repertoire of behavioral responses during everyday experiences. During a potentially dangerous encounter, defensive actions such as "fight, flight, or freeze" are selected for survival. The successful use of behavior is determined by a series of real-time computations combining an animal's internal (i.e., body) and external (i.e., environment) state. Brain-wide neural pathways are engaged throughout this process to detect stimuli, integrate information, and command behavioral output. The hippocampus, in particular, plays a role in the encoding and storing of the episodic information surrounding these encounters as putative "engram" or experience-modified cellular ensembles. Recalling a negative experience then reactivates a dedicated engram ensemble and elicits a behavioral response. How hippocampus-based engrams modulate brain-wide states and an animal's internal/external milieu to influence behavior is an exciting area of investigation for contemporary neuroscience. In this chapter, we provide an overview of recent technological advancements that allow researchers to tag, manipulate, and visualize putative engram ensembles, with an overarching goal of casually connecting their brain-wide underpinnings to behavior. We then discuss how hippocampal fear engrams alter behavior in a manner that is contingent on an environment's physical features as well as how they influence brain-wide patterns of cellular activity. Overall, we propose here that studies on memory engrams offer an exciting avenue for contemporary neuroscience to casually link the activity of cells to cognition and behavior while also offering testable theoretical and experimental frameworks for how the brain organizes experience.

Hippocampal Engrams and Contextual Memory.

Memories are not formed in a vacuum and often include rich details about the time and place in which events occur. Contextual stimuli promote the retrieval of events that have previously occurred in the encoding context and limit the retrieval of context-inappropriate information. Contexts that are associated with traumatic or harmful events both directly elicit fear and serve as reminders of aversive events associated with trauma. It has long been appreciated that the hippocampus is involved in contextual learning and memory and is central to contextual fear conditioning. However, little is known about the underlying neuronal mechanisms underlying the encoding and retrieval of contextual fear memories. Recent advancements in neuronal labeling methods, including activity-dependent tagging of cellular ensembles encoding memory ("engrams"), provide unique insight into the neural substrates of memory in the hippocampus. Moreover, these methods allow for the selective manipulation of memory ensembles. Attenuating or erasing fear memories may have considerable therapeutic value for patients with post-traumatic stress disorder or other trauma- or stressor-related conditions. In this chapter, we review the role of the hippocampus in contextual fear conditioning in rodents and explore recent work implicating hippocampal ensembles in the encoding and retrieval of aversive memories.

The Role of Prefrontal Ensembles in Memory Across Time: Time-Dependent Transformations of Prefrontal Memory Ensembles.

The medial prefrontal cortex (mPFC) plays a critical role in recalling recent and remote fearful memories. Modern neuroscience techniques, such as projection-specific circuit manipulation and activity-dependent labeling, have illuminated how mPFC memory ensembles are reorganized over time. This chapter discusses the implications of new findings for traditional theories of memory, such as the systems consolidation theory and theories of memory engrams. It also examines the specific contributions of mPFC subregions, like the prelimbic and infralimbic cortices, in fear memory, highlighting how their distinct connections influence memory recall. Further, it elaborates on the cellular and molecular changes within the mPFC that support memory persistence and how these are influenced by interactions with the hippocampus. Ultimately, this chapter provides insights into how lasting memories are dynamically encoded in prefrontal circuits, arguing for a key role of memory ensembles that extend beyond strict definitions of the engram.

Engrams of Fear Memory Attenuation.

Fear attenuation is an etiologically relevant process for animal survival, since once acquired information needs to be continuously updated in the face of changing environmental contingencies. Thus, when situations are encountered that were originally perceived as fearful but are no longer so, fear must be attenuated, otherwise, it risks becoming maladaptive. But what happens to the original memory trace of fear during fear attenuation? In this chapter, we review the studies that have started to approach this question from an engram perspective. We find evidence pointing to both the original memory trace of fear being suppressed, as well as it being updated towards safety. These seemingly conflicting results reflect a well-established dichotomy in the field of fear memory attenuation, namely whether fear attenuation is mediated by an inhibitory mechanism that suppresses fear expression, called extinction, or by an updating mechanism that allows the fear memory to reconsolidate in a different form, called reconsolidation-updating. Which of these scenarios takes the upper hand is ultimately influenced by the behavioral paradigms used to induce fear attenuation, but is an important area for further study as the precise cell populations underlying fear attenuation and the molecular mechanisms therein can now be understood at unprecedented resolution.

Unveiling Transcriptional and Epigenetic Mechanisms Within Engram Cells: Insights into Memory Formation and Stability.

Memory traces for behavioral experiences, such as fear conditioning or taste aversion, are believed to be stored through biophysical and molecular changes in distributed neuronal ensembles across various brain regions. These ensembles are known as engrams, and the cells that constitute them are referred to as engram cells. Recent advancements in techniques for labeling and manipulating neural activity have facilitated the study of engram cells throughout different memory phases, including acquisition, allocation, long-term storage, retrieval, and erasure. In this chapter, we will explore the application of next-generation sequencing methods to engram research, shedding new light on the contribution of transcriptional and epigenetic mechanisms to engram formation and stability.

Understanding Others' Distress Through Past Experiences: The Role of Memory Engram Cells in Observational Fear.

For individuals to survive and function in society, it is essential that they recognize, interact with, and learn from other conspecifics. Observational fear (OF) is the well-conserved empathic ability of individuals to understand the other's aversive situation. While it is widely known that factors such as prior similar aversive experience and social familiarity with the demonstrator facilitate OF, the neural circuit mechanisms that explicitly regulate experience-dependent OF (Exp OF) were unclear. In this review, we examine the neural circuit mechanisms that regulate OF, with an emphasis on rodent models, and then discuss emerging evidence for the role of fear memory engram cells in the regulation of Exp OF. First, we examine the neural circuit mechanisms that underlie Naive OF, which is when an observer lacks prior experiences relevant to OF. In particular, the anterior cingulate cortex to basolateral amygdala (BLA) neural circuit is essential for Naive OF. Next, we discuss a recent study that developed a behavioral paradigm in mice to examine the neural circuit mechanisms that underlie Exp OF. This study found that fear memory engram cells in the BLA of observers, which form during a prior similar aversive experience with shock, are reactivated by ventral hippocampal neurons in response to shock delivery to the familiar demonstrator to elicit Exp OF. Finally, we discuss the implications of fear memory engram cells in Exp OF and directions of future research that are of both translational and basic interest.

Terror catastrophizing: association with anxiety, depression, and transgenerational effects.

Background & Objectives: Terror catastrophizing, defined as an ongoing fear of future terrorist attacks, is associated with a higher incidence of anxiety disorders, among other psychological impacts. However, previous studies examining terror catastrophizing's relationship to other mental health disorders are limited. The current study sought to determine if patients diagnosed with anxiety and depression would experience increased terror catastrophizing. Additionally, this study aimed to investigate whether parental terror catastrophizing increases children's internalizing symptoms.Design & Methods: Individuals were randomly drawn from the Danish Civil Registration System and invited to complete a series of questionnaires to measure terror catastrophizing tendency, lifetime parental trauma, and children's internalizing symptoms. In total, n = 4,175 invitees completed the survey of which 933 reported on a child between 6 and 18 years. Responses were analyzed using a generalized linear regression model.Results: Participants diagnosed with anxiety alone or comorbid with depression were more likely to experience symptoms of terror catastrophizing than undiagnosed participants (ß = 0.10, p < .001; ß = 0.07, p = .012). Furthermore, the parental tendency to catastrophize terror was associated with higher internalizing symptoms in children (ß = 0.09, p = .006), even after taking parental diagnoses, as well as lifetime and childhood trauma into account.Conclusion: The results can inform clinical practices to account for a patient's potential to exhibit increased terror catastrophizing tendencies or be more affected by traumatic events. Additionally, they can offer insights for designing novel preventative interventions for the whole family, due to the relation between parental tendencies for terror catastrophizing and the internalizing symptoms observed in children.

Diagnoses of comorbid anxiety and depression tend to have increased terror catastrophizing (TC); however, a sole anxiety diagnosis is associated with more TC, while sole depression is not.Informative for clinical practice to understand how patients with TC tendencies are more likely to be impacted by traumatic events.Parental TC symptoms are linked to internalizing symptoms in children; thus, this could inform the design of novel preventative interventions.

The persian version of the fear-avoidance beliefs questionnaire among iranian post-surgery patients: a translation and psychometrics.

INTRODUCTION: Fear-avoidance beliefs (FAB) play a crucial role in the treatment outcomes of post-surgery patients. These beliefs can lead to activity avoidance, increased pain, and decreased quality of life. Therefore, accurately measuring these beliefs in Iranian patients is of significant importance. The Fear-Avoidance Belief Questionnaire (FABQ) is a patient-reported questionnaire that evaluates individuals' FAB. Since the validity and reliability of the Persian version of FABQ (FABQ-P) have not been assessed based on the Iranian population and sociocultural contexts, the current study has been implemented to determine the reliability and validity of the FABQ-P among Iranian post-operative patients by translation and psychometric properties. METHODS: This methodological study conducted in 2023, a sample of 400 patients who had undergone surgery were selected using a convenience sampling method. The scale used in the study was translated and its psychometric properties were evaluated through network analysis and assessments of construct validity (including exploratory and confirmatory factor analysis), convergent validity, and discriminant validity. Additionally, the study assessed the internal consistency of the scale. RESULTS: The MLEFA results with Promax and Kaiser Normalization rotation yielded two factors explaining 57.91% of the variance, encompassing 13 items. Also, the model was approved by CFA. Convergent and discriminant validity have been confirmed through the following criteria: Average Variance Extracted (AVE) exceeding 0.5, Composite Reliability (CR) surpassing 0.7, and Heterotrait-Monotrait Ratio of Correlations (HTMT) equating to 0.597. As for reliability, Cronbach's alpha, composite reliability (CR), and MaxR for all constructs were greater than 0.7, demonstrating good internal consistency. CONCLUSION: As demonstrated by the results, the FABQ-P has a satisfactory level of reliability along with authentic validity according to the sociocultural contexts of Iranian post-operative patients.