No evidence that arousal affects reactivated memories.

Memory for inherently neutral elements of emotional events is often enhanced on delayed tests - an effect that has been attributed to noradrenergic arousal. Reactivation of a memory is thought to return its corresponding neural ensemble to a state that is similar to when it was originally experienced. Therefore, we hypothesized that neutral elements of memories, too, can be enhanced through reactivation concurrent with heightened arousal. Participants (n = 94) visited the lab for three sessions. During the first session, they encoded 120 neutral memories consisting of an object presented in unique context images. In session two, the 80 objects were reactivated by presenting their corresponding context images, 40 of which were immediately followed by an arousal-inducing shock. Finally, recognition memory for all objects was tested. It was found that memory for reactivated objects was enhanced, but even though the shocks elicited elevations in arousal as indexed by skin conductance, there was no difference between memory of objects reactivated with and without heightened arousal. We thus conclude that arousal, when isolated from other cognitive and affective variables that might impact memory, has no enhancing effect on reactivated memories.

Can neutral episodic memories become emotional? Evidence from facial expressions and subjective feelings.

Maladaptive emotional memories are a transdiagnostic feature of mental health problems. Therefore, understanding whether and how emotional memories can change might help to prevent and treat mental disorders. We tested whether neutral memories of naturalistic events can retroactively acquire positive or negative affect, in a preregistered three-day Modification of Valence in Episodes (MOVIE) paradigm. On Day 1, participants (N = 41) encoded memories of neutral movie scenes, representing lifelike naturalistic experiences. On Day 2, they retrieved each episode before viewing a happy, sad, or neutral scene from the same movie (yielding a within-subjects design with a neutral-negative, neutral-positive, and neutral-neutral condition). On Day 3, participants again retrieved each memory from Day 1. We assessed the affective tone of episodes through facial expressions of positive and negative affect (using facial electromyography, fEMG) and through self-reported feelings. Positive updating of neutral episodes led to increased expressions of positive affect, whereas negative updating led to increased self-reported negative feelings. These results suggest that complex neutral episodic memories can retroactively acquire an affective tone, but the effects were modest and inconsistent across affect readouts. Future research should investigate alternative approaches to updating emotional memories that produce more profound changes in the valence of memories.

Bayesian evaluation of diverging theories of episodic and affective memory distortions in dysphoria.

People suffering from dysphoria retrieve autobiographical memories distorted in content and affect, which may contribute to the aetiology and maintenance of depression. However, key memory difficulties in dysphoria remain elusive because theories disagree how memories of different valence are altered. Here, we assessed the psychophysiological expression of affect and retrieved episodic detail while participants with dysphoria (but without a diagnosed mental illness) and participants without dysphoria relived positive, negative, and neutral memories. We show that participants with dysphoria retrieve positive memories with diminished episodic detail and negative memories with enhanced detail, compared to participants without dysphoria. This is in line with negativity bias but not overgeneral memory bias theories. According to confirmatory analyses, participants with dysphoria also express diminished positive affect and enhanced negative affect when retrieving happy memories, but exploratory analyses suggest that this increase in negative affect may not be robust. Further confirmatory analyses showed that affective responses to memories are not related to episodic detail and already present during the experience of new emotional events. Our results indicate that affective memory distortions may not emerge from mnemonic processes but from general distortions in positive affect, which challenges assumptions of memory theories and therapeutics. Protocol registration: The Stage 1 protocol for this Registered Report was accepted in principle on the 18rd of March 2021. The protocol, as accepted by the journal, can be found at https://doi.org/10.6084/m9.figshare.14605374.v1 .

The generalization of behavioral control over physical threats to social stressors in humans: A pilot fMRI study.

Behavioral control, the ability to manage one's exposure to a given stressor, influences the impacts of both the present and future stressors. Behavioral control over a stressor may decrease stress caused by the stressor, and promote resilience towards future stressors. A lack of behavioral control may exacerbate the stress response and lead to learned helplessness, a generalized view that one cannot control other, unrelated stressors in their environment. The ventromedial prefrontal cortex (vmPFC) may detect the presence of behavioral control over a stressor and communicate this to subcortical regions involved in stress responses, such as the nucleus accumbens (NAc). Building on previous research in animals and humans, we piloted a paradigm to investigate how behavioral control over a physical threat (electric shocks), generalized to responses for a subsequent social stressor (anticipation of public speaking). Our manipulation of behavioral control effected perceived control between groups, increased stress across but not between groups, and no effects generalized to the subsequent social stressor in behavioral, physiological, or neural responses. We discuss refinements to the paradigm to strengthen the manipulation, the potential impacts of statistical power on the present results, and metrics to measure the generalization of behavioral control in addition to vmPFC-subcortical connectivity.

Cardiorespiratory fitness as protection against the development of memory intrusions: A prospective trauma analogue study.

Intrusive and distressing memories are at the core of post-traumatic stress disorder (PTSD). Since cardiorespiratory fitness (CRF) has been linked with improved mental health, emotion regulation, and memory function, CRF may, by promoting these capabilities, protect against the development of intrusions after trauma. We investigated the CRF-intrusion relationship and its potential mediators in 115 healthy individuals, using a trauma film to induce intrusions. As potential mediators, we assessed indices of pre-trauma mental health such as heart rate variability, subjective and psychobiological peri-traumatic responses, and memory. Critically, results showed that higher CRF was related to fewer intrusions, but no mediators emerged for the CRF-intrusion relationship. These results indicate that individuals displaying higher CRF are less prone to develop traumatic memory intrusions. Future studies may want to investigate whether promoting fitness prior to possible trauma exposure can boost resilience against the development of debilitating re-experiencing symptoms of PTSD.

"Yes, I'm interested in taking PrEP!": PrEP interest among women respondents to the European community-based survey "Flash! PrEP in Europe".

The World Health Organization recommends pre-exposure prophylaxis (PrEP) for all populations at substantial risk of HIV infection, including women. However, data regarding PrEP interest among women is lacking, particularly in Europe. Factors associated with interest in using PrEP were assessed among women respondents to the Flash! PrEP in Europe (FPIE) survey. This community-based cross-sectional study, conducted in 12 European countries, aimed to assess PrEP knowledge and interest. "High objective risk" (HOR) was assessed using established risk criteria following EACS and CDC guidelines. Factors associated with interest in using PrEP were assessed in univariable and multivariable logistic regression models. Among 678 women, 12.5% (n = 85) were considered at HOR, 46.8% (n = 317) indicated prior PrEP knowledge and 18.0% (n = 122) reported interest in using PrEP. Among women at HOR, 40.0% (n = 34) were interested in PrEP. Factors significantly associated with PrEP interest in the final multivariable model were: younger age (18-29 years) (aOR 1.91[95CI: 1.07; 3.41]), bad self-perceived financial status (1.84[1.09; 3.11]), migrant status (south to north) (2.87[1.05; 7.89]), single or dating relationship status (1.93[1.23; 3.03]), sexual abuse history (1.86[1.17; 2.97]), "rather high"/ "high" self-perceived HIV risk (3.21[1.32; 7.81]), and HOR (2.49[1.42; 4.35]). These results show that women at HOR and those who perceived themselves to be at high risk are interested in using PrEP. There is a critical need for targeted information and improved access to PrEP to increase uptake of this HIV prevention tool to meet PrEP interest among women.

PrEP Interest Among Men Who Have Sex with Men in the Netherlands: Covariates and Differences Across Samples.

Despite increased availability of pre-exposure prophylaxis (PrEP), PrEP uptake has remained low. To promote uptake, factors related to PrEP interest among relevant target populations warrant investigation. The aim of this study was to provide an analysis of PrEP interest among men who have sex with men (MSM) in the Netherlands, while taking study recruitment strategies into account. We recruited 154 MSM from an LGBT research panel (AmsterdamPinkPanel) and 272 MSM from convenience sampling. Both samples were part of the Flash! PrEP in Europe Survey and were compared on their PrEP interest, usage intentions, and sexual behavior. We conducted logistic regression analyses to discover variables associated with PrEP interest and intentions. Participants from the AmsterdamPinkPanel were less likely to use PrEP, had less knowledge of PrEP, and were less interested in PrEP than participants from convenience sampling. Significant covariates of PrEP interest were being single, more prior PrEP knowledge, sexual risk behaviors, such as not having used a condom during last sex and having ever used drugs in a sexual context, and not participating in the AmsterdamPinkPanel. Adding the recruitment strategy to the regression increased explained variance on top of predictors already described in the literature. Increased sexual risk behavior is related to increased PrEP interest and it helps to identify PrEP target groups. Recruitment strategies have a substantial impact on findings regarding PrEP interest and usage intentions. This study emphasizes the importance of using multiple strategies for recruiting participants to obtain a more comprehensive view of MSM's attitudes toward PrEP.