Olfactory learning in Pieris brassicae butterflies is dependent on the intensity of a plant-derived oviposition cue

Butterflies, like many insects, use gustatory and olfactory cues innately to assess the suitability of an oviposition site and are able to associate colours and leaf shapes with an oviposition reward. Studies on other insects have demonstrated that the quality of the reward is a crucial factor in forming associative memory. We set out to investigate whether the large cabbage white Pieris brassicae (Linnaeus) has the ability to associate an oviposition experience with a neutral olfactory cue. In addition, we tested whether the strength of this association is dependent on the gustatory response to the glucosinolate sinigrin, which is a known oviposition stimulus for P. brassicae. Female butterflies were able to associate a neutral odour with an oviposition experience after a single oviposition experience, both in a greenhouse and in a semi-natural outdoor setting. Moreover, butterflies performed best when trained with concentrations of sinigrin that showed the strongest response by specific gustatory neurons on the forelegs. Our study provides novel insight into the role of both gustatory and olfactory cues during oviposition learning in lepidopterans and contributes to a better understanding of how these insects might be able to adapt to a rapidly changing environment.

Awake bruxism report in a population of dental students with and without ecological momentary assessment monitorization-A randomised trial

OBJECTIVE

The Ecological Momentary Assessment (EMA) concept was the basis for developing a smartphone application for the real-time report of awake bruxism (AB) activities. The aim of this study was to assess the effects of the EMA with a randomised controlled trial designed to compare the frequency of AB reported in two separate single observation points between a group of students monitored over time with an EMA smartphone application and a non-EMA monitored group.

METHODS

Sixty-four (N = 64) dental students (22.3 YO [±2.6]; 52F; 12 M) answered the Oral Behaviour Checklist (OBC-1) and were randomised into an EMA-group (EG) and control group (CG). EG were monitored with a smartphone application for AB report during seven consecutive days and completed three EMA monitoring periods (EMA-1, 2 and 3) at one-month intervals. After the third period (EMA-3), both EG and CG answered again the OBC (OBC-2). Descriptive statistics were performed to characterise the sample. Pearson's chi-squared test, Fixer Exact test and post hoc Z test with Bonferroni correction were performed. The study hypothesis was that EMA could influence the AB reported by the participants because it implies an increase in the awareness, self-recognition, and self-control of bruxism behaviours. The level of significance was set at p < .05.

RESULT

The percentage of participants who changed the report of the activity of clenching their teeth while awake between OBC-1 and OBC-2 was significantly higher among participants in EG, when compared to CG (p = .027). For all other behaviours reported the within- and between-group differences from OBC-1 to OBC-2 were not significant. Clenching and bracing were the most frequently reported, whilst grinding was the less frequent behaviour.

CONCLUSION

A smartphone-based EMA approach demonstrated be useful to monitor AB over time, increasing individual's awareness, particularly to bracing and clenching behaviours.

A translational and multidisciplinary approach to studying the Garcia effect, a higher form of learning with deep evolutionary roots

Animals, including humans, learn and remember to avoid a novel food when its ingestion is followed, hours later, by sickness - a phenomenon initially identified during World War II as a potential means of pest control. In the 1960s, John Garcia (for whom the effect is now named) demonstrated that this form of conditioned taste aversion had broader implications, showing that it is a rapid but long-lasting taste-specific food aversion with a fundamental role in the evolution of behaviour. From the mid-1970s onward, the principles of the Garcia effect were translated to humans, showing its role in different clinical conditions (e.g. side-effects linked to chemotherapy). However, in the last two decades, the number of studies on the Garcia effect has undergone a considerable decline. Since its discovery in rodents, this form of learning was thought to be exclusive to mammals; however, we recently provided the first demonstration that a Garcia effect can be formed in an invertebrate model organism, the pond snail Lymnaea stagnalis. Thus, in this Commentary, after reviewing the experiments that led to the first characterization of the Garcia effect in rodents, we describe the recent evidence for the Garcia effect in L. stagnalis, which may pave the way for future studies in other invertebrates and mammals. This article aims to inspire future translational and ecological studies that characterize the conserved mechanisms underlying this form of learning with deep evolutionary roots, which can be used to address a range of different biological questions.

Invertebrates as models of learning and memory: investigating neural and molecular mechanisms

In this Commentary, we shed light on the use of invertebrates as model organisms for understanding the causal and conserved mechanisms of learning and memory. We provide a condensed chronicle of the contribution offered by mollusks to the studies on how and where the nervous system encodes and stores memory and describe the rich cognitive capabilities of some insect species, including attention and concept learning. We also discuss the use of planarians for investigating the dynamics of memory during brain regeneration and highlight the role of stressful stimuli in forming memories. Furthermore, we focus on the increasing evidence that invertebrates display some forms of emotions, which provides new opportunities for unveiling the neural and molecular mechanisms underlying the complex interaction between stress, emotions and cognition. In doing so, we highlight experimental challenges and suggest future directions that we expect the field to take in the coming years, particularly regarding what we, as humans, need to know for preventing and/or delaying memory loss. This article has an associated ECR Spotlight interview with Veronica Rivi.

Two Case Reports of Tapering Sedative-hypnotic Drugs Through Classical Conditioning Using Herbal Medicine (CARE-compliant)

RATIONALE

Sedative-hypnotic drugs (SHDs) used for insomnia are recommended for short-term use owing to concerns regarding abuse and dependence. Nevertheless, drug discontinuation is challenging owing to rebound insomnia that occurs when the SHD is ceased. Therefore, a strategy is required to reduce or discontinue SHDs, while minimizing rebound insomnia.

PATIENT CONCERNS

The present report discusses the cases of a 72-year-old man and 27-year-old man with insomnia. Both patients had been taking SHDs for more than 2 months.

DIAGNOSES

Both patients were diagnosed with primary insomnia.

INTERVENTIONS AND OUTCOMES

After 2 weeks of classical conditioning (CC) using Hwangryunhaedok-tang (HHT), both patients succeeded in tapering SHD; the Korean version of the insomnia severity index of patient 1 dropped from 14 to 5, and that of patient 2 dropped from 28 to 11. In the final follow-up, the index dropped to 2 and 3, respectively.

LESSONS

The CC, a concept emerging in psychology, could be a new strategy for tapering drugs. In this case, SHDs, which had been taken for a long time, were successfully reduced or discontinued through CC using HHT. Herbal medicine such as HHT is selected as a neutral stimulus for CC because the risk of rebound phenomenon is low as the compounds of herbal medicine have high structural similarities with human metabolites. Both patients in this study reported no particular challenges when HHT was discontinued. However, further studies are needed that will assist in tapering anticonvulsants or steroids as well as SHDs.

Psychedelics as Tools for Belief Transmission. Set, Setting, Suggestibility, and Persuasion in the Ritual Use of Hallucinogens

The use of psychedelics in the collective rituals of numerous indigenous groups suggests that these substances are powerful catalysts of social affiliation, enculturation, and belief transmission. This feature has recently been highlighted as part of the renewed interest in psychedelics in Euro-American societies, and seen as a previously underestimated vector of their therapeutic properties. The property of psychedelics to increase feelings of collective belonging and transmission of specific cultural values or beliefs raise, however, complex ethical questions in the context of the globalization of these substances. In the past decades, this property has been perceived as problematic by anticult movements and public authorities of some European countries, claiming that these substances could be used for "mental manipulation." Despite the fact that this notion has been widely criticized by the scientific community, alternative perspectives on how psychedelic experience supports enculturation and social affiliation have been yet little explored. Beyond the political issues that underlie it, the re-emergence of the concept of "psychedelic brainwashing" can then be read as the consequence of the fact that the dynamic through which psychedelic experience supports persuasion is still poorly understood. Beyond the unscientific and politically controversed notion of brainwashing, how to think the role of psychedelics in the dynamics of transmission of belief and its ethical stakes? Drawing on data collected in a shamanic center in the Peruvian Amazon, this article addresses this question through an ethnographic case-study. Proposing the state of hypersuggestibility induced by psychedelics as the main factor making the substances powerful tools for belief transmission, I show that it is also paradoxically in its capacity to produce doubt, ambivalence, and reflexivity that psychedelics support enculturation. I argue that, far from the brainwashing model, this dynamic is giving a central place to the agency of the recipient, showing that it is ultimately on the recipient's efforts to test the object of belief through an experiential verification process that the dynamic of psychedelic enculturation relies on. Finally, I explore the permanence and the conditions of sustainability of the social affiliation emerging from these practices and outline the ethical stakes of these observations.

Utility of Smartphone-based real-time report (Ecological Momentary Assessment) in the assessment and monitoring of awake bruxism: A multiple-week interval study in a Portuguese population of university students

PURPOSE

The Ecological Momentary Assessment (EMA) concept was the basis for developing a smartphone application for the on-time report of awake bruxism (AB) activities. This study aims to monitor AB report over time in a population of healthy young adults.

METHODS

A population of young adults recruited among dental students in good general health was recruited. All answered to a questionnaire, including the Oral Behavior Checklist (OBC-1). They were then monitored with a smartphone application for AB report during seven consecutive days and completed three further observation periods (EMA-1, 2 and 3) at one-month intervals. After the third period (EMA-3), participants answered again the OBC questionnaire (OBC-2). Changes over time were described, and Pearson Correlation test was performed to assess the correlation between EMA and OBC items reports. A significance level of p = .01 was set.

RESULTS

Thirty-one University students completed the study protocol. Answers to the OBC showed an increase in the prevalence of self-reported bracing and teeth clenching from the first to second report (38.7%-54.8% and 77.4%-90.3%, respectively). A slight increase in the 'relaxed' condition (62.5%-69.0%) was observed with EMA-based smartphone application over time. No correlation between OBC items and EMA was detected between OBC-1 and EMA-1. A moderate positive correlation in bracing report (+0.509, p = .01) and weak positive correlation in teeth contact report (+0.380, p = .05) were found between OBC-2 and EMA-3.

CONCLUSION

Using a smartphone-based approach to AB report may be helpful to monitor AB over time and increase an individual's awareness to recognise actions such as bracing and teeth contact concerning the single-time report.

The kingdom of dogs: Understanding Pavlov’s experiments as human–animal relationships

The growth of Human–Animal Studies, multi-species, and posthuman scholarship reflects an “animal turn” offering important theoretical, ethical, and methodological challenges to humanities, science, and social science disciplines, though psychology, in particular, has been slow to engage with these developments. This article is the first to apply the conceptual lens of the “animal turn” to Pavlov’s experiments with dogs. It is unique in applying in particular the work of feminist cultural theorist Donna Haraway, to radically reframe the human–animal relationship at the core of these landmark experiments. This original portrait is contrasted with contemporary retellings of those experiments which ignore or are indifferent to the complexities of that relationship. Paying attention to nonhuman others that constitute animal experimentation in psychology, historically, today, and in retellings, is argued to be a vitally important step for psychology today. The analysis provided constitutes a distinctive, radical shift in the way psychology might approach the lives of nonhuman animals, in its own past and present, with far-reaching implications for the future development of psychology.

Analysis of Mutants Suggests Kamin Blocking in C. elegans is Due to Interference with Memory Recall Rather than Storage

Higher-order conditioning phenomena, including context conditioning and blocking, occur when conditioning to one set of stimuli interacts with conditioning to a second set of stimuli to modulate the strength of the resultant memories. Here we analyze higher-order conditioning in the nematode worm Caenorhabditis elegans, demonstrating for the first time the presence of blocking in this animal, and dissociating it from context conditioning. We present an initial genetic dissection of these phenomena in a model benzaldehyde/NH₄Cl aversive learning system, and suggest that blocking may involve an alteration of memory retrieval rather than storage. These findings offer a fundamentally different explanation for blocking than traditional explanations, and position C. elegans as a powerful model organism for the study of higher order conditioning.

Neural Oscillatory Correlates for Conditioning and Extinction of Fear

The extinction of conditioned-fear represents a hallmark of current exposure therapies as it has been found to be impaired in people suffering from post-traumatic stress disorder (PTSD) and anxiety. A large body of knowledge focusing on psychophysiological animal and human studies suggests the involvement of key brain structures that interact via neural oscillations during the acquisition and extinction of fear. Consequently, neural oscillatory correlates of such mechanisms appear relevant regarding the development of novel therapeutic approaches to counterbalance abnormal activity in fear-related brain circuits, which, in turn, could alleviate fear and anxiety symptoms. Here, we provide an account of state-of-the-art neural oscillatory correlates for the conditioning and extinction of fear, and also deal with recent translational efforts aimed at fear extinction by neural oscillatory modulation.

Blocking of conditioning of tentacle lowering in the snail (Helix aspersa)

Experiment 1 established the effectiveness of an appetitive conditioning of odours procedure with snails ( Helix aspersa) that was subsequently used for the study of blocking. In this important phenomenon, the conditioning of a CS1 (where CS is the conditioned stimulus) prior to conditioning of a compound, CS1CS2, blocked the conditioning to the CS2. Experiments 2a, 2b, and 2c demonstrated this associative effect using three different experimental controls. Experiments 3a and 3b replicated the blocking effect and allowed us to reject an explanation of blocking based on generalized effects of several treatments of diverse stimuli in blocking and control groups (the pseudoblocking effect). The implications of these results for the study of invertebrate cognition by means of conditioning techniques are discussed.