Marie-Hélène Monfils

Anxiety and related disorders are highly prevalent (Baxter et al., 2012) and associated with significant distress and disability (Bandelow & Michaelis, 2015; Olatunji et al., 2007). Fortunately, in...

Collective intelligence (CI) is the capacity of groups to outperform individuals in tasks such as decision-making, coordination and problem-solving. A significant challenge to studying CI is that it encompasses a wide variety of behaviours that are underpinned by different mechanisms. To balance inclusivity with conceptual clarity, we propose a typology of CI mechanisms including self-organized coordination, distributed decision-making, cooperative problem-solving, statistical aggregation and culture and cultural improvement. This typology helps clarify the minimum requirements for CI and how other, more cognitive complex mechanisms may have layered on top of these. As model comparative species, we focus on two ecologically successful generalists, rats (Rattus) and cockroaches (Blattodea). Cockroaches show evidence of collective behaviours, but these rely on a more ancestral set of mechanisms that lack cognitive complexity. Conversely, rats share important ecological traits with cockroaches but exhibit social traits found in primates, including cultural learning, distributed decision-making, empathy and cooperation. This comparison can show how similar collective outcomes can emerge even with disparate mechanisms and provide a way to uncover evolutionary design principles of CI. Ultimately, we can use such comparisons to determine which features of CI are universal properties of collectives and which are contingent on specific cognitive adaptations. This article is part of the theme issue ‘The evolution of collective intelligence’.

Gonadal hormones (e.g., estradiol and progesterone) influence response to, and preference for, drugs in females; however, how hormonal contraceptives, synthetic hormones that decrease gonadal hormone levels, affect drug preference is not known. The current experiment investigated whether oral administration of levonorgestrel (LNG), a synthetic progestin used in hormonal contraceptives, would lead to a reduction in amphetamine (AMPH) preference. Female rats were tested for their AMPH preference over 3 days (which also served as extinction sessions) after receiving oral administration of LNG (250 μg, 500 μg, or 2 mg) or during an estrous cycle stage associated with higher levels of gonadal hormones (i.e., proestrus/estrus). Our results show that AMPH preference was reduced for females on 500 μg and 2 mg of LNG across extinction sessions. Interestingly, only the 2 mg LNG dose led to a disruption in the naturally occurring estrous cycle. Uterine horn width, an index of estrogen exposure, was decreased in all LNG groups, but only the 500 μg and 2 mg LNG groups showed suppression of gonadal hormones, suggesting that both doses are sufficient for contraceptive use in rats. Our study demonstrates an effective and noninvasive oral LNG administration method in a rat model and further shows reduced AMPH preference by LNG. (PsycInfo Database Record (c) 2025 APA, all rights reserved).

Cues associated with alcohol consumption can trigger cravings, seeking behaviour and relapse after abstinence in individuals with alcohol use disorder (AUD). These conditioned responses can be attenuated through extinction learning, a core component of cue exposure therapy (CET). CET is effective in some individuals with AUD but not all, so it is necessary to develop strategies to identify and intervene with individuals unlikely to benefit from CET. Another method for attenuating conditioned responding is retrieval‐extinction, which renders the original associative memory labile via distinct neural mechanisms. We recently demonstrated that CO ₂ reactivity predicts extinction memory for both fear and food cues, and fear memory after retrieval‐extinction, and CO ₂ ‐induced orexin/c‐Fos colocalization predicts fear extinction memory. The purpose of the current study was to examine whether the predictive power of CO ₂ reactivity might extend to alcohol‐seeking behaviour after extinction or retrieval‐extinction in male and female rats. We also examined the relationship between CO ₂ reactivity, return of alcohol‐seeking behaviour and CO ₂ ‐induced orexin/c‐Fos colocalization. Male and female rats first underwent alcohol drinking induction in the homecage followed by dependence via exposure to chronic intermittent ethanol vapour or control air and homecage drinking. All rats then underwent Pavlovian alcohol conditioning followed by either standard extinction or retrieval‐extinction. They then received a long‐term memory (LTM) test and CO ₂ challenge followed by euthanasia for brain harvesting. CO ₂ reactivity differentially predicted LTM after extinction and retrieval‐extinction. There were no relationships between orexin/c‐Fos colocalization and CO ₂ reactivity or LTM. The predictive power of CO ₂ reactivity extends to alcohol‐seeking behaviour after extinction and retrieval‐extinction in alcohol dependent and nondependent male and female rats, while its relationship with orexin/c‐Fos colocalization does not. CO ₂ reactivity could be used as a screening tool to determine whether an individual may be a good candidate for CET or a retrieval‐extinction–based approach.

Fear extinction is foundational to exposure therapy and thus studying strategies to optimize fear extinction is relevant for clinical practice. This paper provides a critical review of translational research on pharmacological enhancement of fear extinction, concentrating mostly on D-cycloserine (DCS), the agent with the most extensive evidence base across levels of analyses. Despite early promise, results across preclinical, human laboratory, and clinical trials have been mixed. We identify factors that may account for these inconsistent findings, including differences in study design, selection of subjects, sample size, and measurement approaches. We emphasize the need for a rigorous mechanistic research agenda that assesses extinction processes – acquisition, consolidation, and retrieval – as distinct mechanistic targets, and examines the relation between changes in these fear extinction processes and clinical outcomes. Finally, we discuss opportunities to advance translational research in this area leveraging extant collaborative infrastructures to improve quality, efficiency and ultimately the availability of effective clinical strategies.

Here, we describe the efforts we dedicated to the challenge of modifying entrenched emotionally laden memories. In recent years, through a number of collaborations and using a combination of behavioral, molecular, and computational approaches, we: (a) developed novel approaches to fear attenuation that engage mechanisms that differ from those engaged during extinction (Monfils), (b) examined whether our approaches can generalize to other reinforcers (Lee, Gonzales, Chaudhri, Cofresi, and Monfils), (c) derived principled explanations for the differential outcomes of our approaches (Niv, Gershman, Song, and Monfils), (d) developed better assessment metrics to evaluate outcome success (Shumake and Monfils), (e) identified biomarkers that can explain significant variance in our outcomes of interest (Shumake and Monfils), and (f) developed better basic research assays and translated efforts to the clinic (Smits, Telch, Otto, Shumake, and Monfils). We briefly highlight each of these milestones and conclude with final remarks and extracted principles. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Anxiety and related disorders are a significant public-health burden with rising prevalence in the wake of the COVID-19 pandemic. As demand for effective anxiety treatment increases, so too does the need for strategies to bolster treatment outcomes. Research on the mechanisms of exposure therapy, the frontline behavioral treatment, will be critically important for optimizing clinical outcomes. We outline an initial agenda for future research on the mechanisms of change of exposure therapy, developed in collaboration with a large international team of researchers through the Exposure Therapy Consortium. Key questions and recommendations for future research focus on four priority areas: conceptualization, measurement, study design/analysis, and individual/contextual differences. Rising to the challenge of addressing these questions will require coordinated action and availability of centralized tools that can be used across trials, settings, and research groups.

Social transmission of fear occurs in a subset of individuals, where an Observer displays a fear response to a previously neutral stimulus after witnessing or interacting with a conspecific Demonstrator during memory retrieval. The conditions under which fear can be acquired socially in rats have received attention in recent years, and suggest that social factors modulate social transmission of information. We previously found that one such factor, social rank, impacts fear conditioning by proxy in male rats. Here, we aimed to investigate whether social roles as determined by nape contacts in females, might also have an influence on social transmission of fear. In-line with previous findings in males, we found that social interactions in the home cage can provide insight into the social relationship between female rats and that these relationships predict the degree of fear acquired by-proxy. These results suggest that play behavior affects the social transfer/transmission of information in female rats.