[Alcohol consumption during the COVID-19 pandemic among French-speaking Belgian students : uncertainty and psychological distress]. / Face à la COVID-19. Consommation d'alcool pendant la pandémie de COVID-19 chez les étudiants belges francophones : incertitude et détresse psychologique.

The COVID-19 pandemic has had a deleterious impact on students. Studies showed an increase in anxiety-depressive symptoms and changes in certain health behaviours (smoking, drugs, etc.). The aim of the present study is to measure whether students' alcohol consumption changed during the third confinement (frequency and quantity) in relation to the factor of intolerance to uncertainty. The study was conducted on a sample of 273 French-speaking Belgian students (Universities and High Schools). The students answered questionnaires measuring their psycho-emotional state, alcohol consumption and intolerance of uncertainty and its mechanisms. Results showed that 65 % of the students had anxiety symptoms. Alcohol consumption remained moderate, with 85 % having not changed the frequency of consumption and 89 % their quantity of alcohol. Finally, the results indicated that the increase in alcohol consumption was essentially linked to positive expectations about the effects of alcohol, but not to measures of anxiety or intolerance of uncertainty. The study highlights the need for national prevention strategies to detect psychological distress in post-pandemic students.

La pandémie de COVID-19 a eu un impact délétère sur les étudiants. Les études montrent une augmentation de symptômes anxio-dépressifs et la modification de certains comportements de santé (tabac, drogue, etc.). L'objectif de la présente étude est de mesurer si la consommation d'alcool des étudiants a changé durant le troisième confinement (fréquence et quantité) en lien avec le facteur d'intolérance à l'incertitude. L'étude a été menée sur un échantillon de 273 étudiants belges francophones (Universités et Hautes Ecoles). Les étudiants ont répondu à des questionnaires mesurant leur état psycho-émotionnel, la consommation d'alcool et l'intolérance à l'incertitude et ses mécanismes. Les résultats montrent que 65 % des étudiants ont des symptômes anxieux. La consommation d'alcool reste modérée avec 85 % n'ayant pas modifié la fréquence de consommation et 89 % leur quantité d'alcool. Enfin, les résultats indiquent que l'augmentation de la consommation d'alcool était essentiellement liée aux attentes d'effets positifs de l'alcool, mais pas en lien avec les mesures d'anxiété ou d'intolérance à l'incertitude. L'étude met en évidence l'importance de mettre en place des stratégies nationales de prévention pour détecter la détresse psychologique des étudiants post-pandémie.

Effects of social housing conditions on ethanol-induced behavioral sensitization in Swiss mice.

RATIONALE: In previous animal model studies, it was shown that drug sensitization is dependent upon physical environmental conditions. However, the effects of social housing conditions on drug sensitization is much less known. OBJECTIVE: The aim of the present study was to investigate the effects of social conditions, through the size of housing groups, on ethanol stimulant effects and ethanol-induced behavioral sensitization in mice. MATERIALS AND METHODS: Male and female Swiss mice were housed in groups of different sizes (isolated mice, two mice per cage, four mice per cage and eight mice per cage) during a six-week period. A standard paradigm of ethanol-induced locomotor sensitization was then started with one daily injection of 2.5 g/kg ethanol for 8 consecutive days. RESULTS: The results show that social housing conditions affect the acute stimulant effects of ethanol. The highest stimulant effects were observed in socially isolated mice and then gradually decreased as the size of the group increased. Although the rate of ethanol sensitization did not differ between groups, the ultimate sensitized levels of ethanol-induced stimulant effects were significantly reduced in mice housed in groups of eight. CONCLUSIONS: These results are consistent with the idea that higher levels of acute and sensitized ethanol stimulant effects are observed in mice housed in stressful housing conditions, such as social isolation.

Impact of a pre-test measurement of alcohol craving in cue-exposure studies: Relationship with social desirability and demand effects.

Craving is one of the most studied concepts in the field of addiction. It is often investigated with repeated-measure experimental designs using self-reported scales. However, the explicit nature of self-reported craving scales may make them vulnerable to social desirability and demand effects. The aim of the present study was to test whether a pre-experimental measurement of craving affects its post-experimental assessment after an alcohol video exposure and whether these changes relate to social desirability, demand effects, and alcohol consumption. Seventy-five healthy volunteers aged 18-30 years were randomly assigned to two experimental groups: a pre-post and a post-only craving assessment group. They were invited to watch an alcohol-related video. Social desirability, demand effects, engagement toward the video, and severity of alcohol consumption were assessed in all participants. The results showed a significant effect of alcohol consumption (p < .001, η2p = .09) on post-experimental craving. The main effect of the repeated measure of craving was also significant (p = .04, η2p = .001), together with the interaction between these two variables (p = .03, η2p = .06). The pre-experimental craving measurement increased its post-experimental levels, but only in heavy drinkers. However, no evidence was found that these changes were related to social desirability or demand effects. Additional exploratory analyses indicated that craving increase in high alcohol drinkers was mediated by a stronger engagement toward the alcohol-related video. In summary, the repeated measurement of craving with explicit scales has a significant impact on the results of alcohol craving studies and may not always be desirable, especially when the true purpose of the study needs to be hidden from the participants. However, the present results also suggest that the pre-post experimental design is advisable when the experimenters seek to maximize the relationship between the individual levels of alcohol consumption and alcohol cue-exposure craving changes.

Using 360-degree immersive videos to assess multiple transdiagnostic symptoms: A study focusing on fear of negative evaluation, paranoid thoughts, negative automatic thoughts, and craving.

Over the last 20 years, virtual reality (VR) has gained a great interest for both assessment and treatment of various psychopathologies. However, due to high costs and material specificity, VR remains disadvantageous for clinicians. Adopting a multiple transdiagnostic approach, this study aims at testing the validity of a 360-degree immersive video (360IV) for the assessment of five common psychological symptoms (fear of negative evaluation, paranoid thoughts, negative automatic thoughts, craving for alcohol and for nicotine). A 360IV was constructed in the Darius Café and included actors behaving naturally. One hundred and fifty-eight adults from the general population were assessed in terms of their proneness towards the five symptoms, were then exposed to the 360IV and completed measures for the five state symptoms, four dimensions of presence (place, plausibility, copresence and social presence illusions) and cybersickness. Results revealed that the five symptoms occurred during the immersion and were predicted by the participants' proneness towards these symptoms. The 360IV was also able to elicit various levels of the four dimensions of presence while producing few cybersickness. The present study provides evidence supporting the use of the 360IV as a new accessible, ecological, and standardized tool to assess multiple transdiagnostic symptoms. Supplementary Information: The online version contains supplementary material available at 10.1007/s10055-023-00779-y.

Voluntary alcohol binge-drinking in adolescent C57Bl6 mice induces delayed appearance of behavioural defects in both males and females.

Adolescence is a developmental period characterized by significant changes in brain architecture and behaviour. The immaturity of the adolescent brain is associated with heightened vulnerability to exogenous agents, including alcohol. Alcohol is the most consumed drug among teenagers, and binge-drinking during adolescence is a major public health concern. Studies have suggested that adolescent alcohol exposure may interfere with the maturation of frontal brain regions and lead to long-lasting behavioural consequences. In this study, by using a slightly modified version of the Drinking in the Dark paradigm, adolescent C57Bl6 mice reach high blood alcohol concentration after voluntary binge-drinking. In order to assess short- and long-term consequences of adolescent alcohol exposure (AAE), a battery of behavioural tests was performed during late adolescence and during adulthood. We showed that AAE had no short-term effect on young mice behaviour but rather increased anxiety- and depressive-like behaviours, as well as alcohol consumption during adulthood. Moreover, alcohol binge-drinking during adolescence dramatically decreased recognition memory performances and behavioural flexibility in both adult males and females. Furthermore, we showed that voluntary consumption of alcohol during adolescence did not trigger any major activation of the innate immune system in the prefrontal cortex. Together, our data suggest that voluntary alcohol binge-drinking in adolescent mice induces a delayed appearance of behavioural impairments in adulthood.

Using 360° immersive videos to assess paranoia in a non-clinical population.

Introduction: For the past two decades, virtual reality (VR) has proven to be an innovative approach for the assessment of state paranoia. However, the use of VR remains costly, and avatars are still far from realistic in terms of facial and bodily expressions. The present study aimed to test the validity of three 360° immersive videos (360IVs) as an accessible and realistic alternative for the assessment of non-clinical state paranoia.Method: Three 360IVs were created (a Lift, a Library and a Bar) and included actors behaving naturally. One hundred and fifty healthy students were assessed in terms of their proneness towards trait paranoia, were then exposed to one of the three 360IVs, and finally completed measures of state paranoia, sense of presence and cybersickness.Results: Results revealed the presence of various interpretations about the actor's attitudes in the three 360IVs. Also, paranoid thoughts were predicted by proneness towards trait paranoia in two out of the three 360IVs. Furthermore, moderate levels of sense of presence and low levels of cybersickness were observed for each 360IV.Conclusion: The present study provides evidence in favour of the use of 360IVs as a new accessible, realistic, and standardised tool to assess state paranoia in non-clinical samples.

Relative stability of alexithymia and openness to emotions in one psychiatric day hospital setting.

Alexithymia (literally, difficulty finding words for emotions) and openness to emotions (OE: referring to the cognitive representation, communication, regulation, perception of internal and external bodily sensations, and social restriction of emotions) are strongly linked to psychopathology. The absolute and relative stability hypotheses were tested in order to determine whether significant changes occurred on these constructs after therapy, a condition where changes were expected for both constructs. Negative attitudes toward treatment (NTI) and perceived social support (PSS) were expected to significantly predict alexithymia and OE. Patients (N = 179) who participated in this longitudinal study filled in the Toronto Alexithymia Scale, the Dimensions of Openness to Emotions Scale, the NTI subscale, the Multidimensional Scale of Perceived Social Support, and the Social Desirability Scale. After treatment, we observed significant decrease of all alexithymia scores and significant increases of three OE scores, that is, cognitive representation, communication, and regulation of emotions. Regression analyses revealed that gender, age, NTI, and PSS were significant predictors of alexithymia and OE. NTI strongly predicted lower OE levels and higher alexithymia levels, whereas PSS had opposite predicting effects on these constructs. In conclusion, the significant changes, and the moderate to high correlational levels observed between before and after alexithymia and OE scores, strengthen the relative stability hypothesis for both constructs. In addition, PSS represents a protective factor and NTI a vulnerability indicator for therapists. Our aim is to optimize treatment by providing therapists treating emotion difficulties a more concrete array of variables that potentially either promote or subvert recovery.

Alcohol Craving in Heavy and Occasional Alcohol Drinkers After Cue Exposure in a Virtual Environment: The Role of the Sense of Presence.

The development of new technologies, and more specifically the opportunity to immerse participants in virtual controlled environments, provides a new ecological framework for researchers to study complex behaviors. This experiment aimed to compare post-immersion craving in occasional and heavy alcohol drinkers. Twenty-two occasional drinkers and eighteen heavy drinkers were recruited and immersed in a virtual bar, including alcoholic beverages. After the exposure, heavy drinkers reported a significantly higher craving than occasional drinkers. Post-immersion alcohol craving was significantly related to the levels of perceived ecological validity of the virtual environment. Finally, a moderation analysis suggested that the levels of craving more strongly increased with perceived ecological validity in heavy drinkers than in occasional drinkers. Therefore, the perceived ecological validity was an important experimental parameter to study craving in a virtual environment. These results further suggested that virtual reality might be a useful tool for both the scientific study of alcohol addiction and the treatment of alcohol dependence and relapse.

Long-term exposure to daily ethanol injections in DBA/2J and Swiss mice: Lessons for the interpretation of ethanol sensitization.

Most mice ethanol sensitization studies focused on neurobiology at the expense of its behavioral characterization. Furthermore, relatively short ethanol exposures (10 to 20 injections) were used in these studies. The first aim of the present study is to better characterize the development and expression of ethanol sensitization after an extended exposure of 45 daily injections. In some previous studies, mice were classified as "respondent" and "resistant" to ethanol sensitization. The second aim of the present study is to test the long-term reliability of such categorizations and the consequences of their use on the interpretation of the ethanol sensitization results. Swiss and DBA/2J female mice received 45 consecutive daily ethanol administrations (respectively 2.5 and 2.0 g/kg) and their locomotor activity was daily recorded to test the development of ethanol sensitization. At the end of the procedure, a challenge test assessed the inter-group ethanol sensitization.The results of the present study show that ethanol sensitization continues to develop beyond 20 days to reach maximal levels after about 25 injections in DBA/2J mice and 40 injections in Swiss mice, although the core phase of the development of ethanol sensitization occurred in both strains during the first 20 days. Remarkably, ethanol sensitization after such a long daily ethanol treatment resulted in both an upward shift of the magnitude of ethanol stimulant effects and a prolongation of these effects in time (up to 30 minutes). Mice classified as "resistant to ethanol sensitization" according to previous studies developed very significant levels of ethanol sensitization when tested after 45 ethanol injections and are best described as showing a delayed development of ethanol sensitization. Furthermore, mice classified as respondent or resistant to ethanol sensitization also differ in their acute response to ethanol, such that it is difficult to ascertain whether these classifications are specifically related to the sensitization process.

Investigating the reciprocal relationships between locomotor sensitization to ethanol and PTSD-like clusters in DBA/2J mice.

BACKGROUND: Post-traumatic stress disorder (PTSD) and alcohol use disorder (AUD) are two conditions that co-occur frequently. The mechanistic explanations of this co-morbidity are still unclear. The goal of this study was twofold. First to investigate whether PTSD reduces the threshold for the acquisition of ethanol sensitization in an animal model of PTSD. Then to investigate whether ethanol sensitization modulates the expression of PTSD. METHODS: 152 female inbred DBA/2 J mice were submitted to an inescapable footshock paradigm to induce a PTSD-like condition (PTSDLC) and to a paradigm of locomotor sensitization to ethanol. In a first experiment, mice were submitted to the PTSDLC and then repeatedly injected with either saline, 1 g/kg ethanol or 2 g/kg ethanol. Their sensitization to the locomotor stimulant effects of ethanol was then tested in an open field. In a second experiment, mice were first sensitized to the locomotor stimulant effects of ethanol and then tested for their behavioral response to PTSDLC. RESULTS: In the first experiment, PTSDLC failed to induce a significant locomotor sensitization at the subthreshold dose of 1 g/kg ethanol. However, with 2 g/kg ethanol, a stronger ethanol sensitization was observed in mice submitted to the footshock relative to the control group. In the second experiment, ethanol sensitization increased only some of the behavioral clusters of PTSDLC, namely the fear generalization in a new context. CONCLUSION: PTSDLC did not reduce the dose threshold for the acquisition of ethanol sensitization but strengthened the development of ethanol sensitization with effective doses. This suggests that PTSD might interact with one of the mechanisms underlying the development of alcohol sensitization. When the relationship between ethanol sensitization and PTSDLC is tested in the reverse direction, the present study only shows a significant effect of ethanol administration on the "sensitized fear" PTSD cluster.

Smoking addiction: the shift from head to hands: Approach bias towards smoking-related cues in low-dependent versus dependent smokers.

The dual process theory is central to several models of addiction, implying both an increase of stimulus salience and deficits in inhibitory control. Our major aim is to provide behavioral evidence for an approach bias tendency in smokers and more specifically during smoking cue exposure. The second aim is to examine whether this bias differs in low-dependent versus dependent smokers. Thirty-two smokers (17 low dependent and 15 dependent; cut-off FTND of 4) and 28 non-smokers performed a modified Go/NoGo task using tobacco-related words and neutral words as stimuli. Smokers generally made more mistakes and tended to be faster for smoking-related cues specifically. Low dependents acknowledged more their dependency in declarative questionnaires while making more errors and being slower specifically on smoking cues; dependent smokers were less prone to indicate their addiction, but were faster and accurate when it came to picking the smoking cues. These results suggest that a shift has operated from a mental preoccupation with smoking in the low-dependent group, to smoking as a motor habit in our dependent group. This finding invites experts to rethink smoking addiction in the light of this crucial moment, namely, the shift "from head to hands".

Alcohol-cue exposure decreases response inhibition towards alcohol-related stimuli in detoxified alcohol-dependent patients.

The induction of alcohol craving and the cognitive processing of alcohol-related stimuli in alcohol-dependent patients have been reported to compete with inhibitory control and contribute to alcohol relapse. The aim of the present study is to investigate whether the induction of a craving state, using an alcohol cue exposure paradigm, influences response inhibition towards both neutral stimuli and alcohol-related stimuli in alcohol-dependent patients. Thirty-one detoxified alcohol-dependent patients were exposed to either their preferred alcoholic beverage or to a glass of water. They then performed a modified stop signal task, which used alcohol-related words, neutral words and non-words, and a lexical decision as the Go response. The alcohol-cue exposure group reported significantly higher alcohol craving and showed higher percentages of commission errors towards alcohol-related words than the control group. All participants, but especially those of the alcohol-cue exposure group, showed also shorter reaction times when alcohol words were used as targets in go trials. The induction of alcohol craving in detoxified alcohol-dependent patients increases the motivational salience value of alcohol stimuli, leading them to automatically approach alcohol-related cues and therefore impairing response inhibition towards those stimuli.

Accurate Control of 17ß-Estradiol Long-Term Release Increases Reliability and Reproducibility of Preclinical Animal Studies.

Estrogens are the subject of intensive researches aiming to elucidate their mechanism of action on the various tissues they target and especially on mammary gland and breast cancer. The use of ready-to-use slow releasing devices to administer steroids, especially estrogens, to small experimental animals remains the method of choice in terms of animal well-being and of safety for both the researcher and the animal. In this study, we evaluated and compared, in vitro and in vivo, the release kinetic of estradiol (E2) over sixty days from two different slow-releasing systems: the matrix pellet (MP) and the reservoir implant (RI). We compared the impact of these systems in three E2-sensitive mouse models : mammary gland development, human MCF7 adenocarcinoma xenograft and mouse melanoma progression. The real amount of E2 that is released from both types of devices could differ from manufacturer specifications due to inadequate release for MP and initial burst effect for RI. Compared to MP, the interindividual variability was reduced with RI thanks to a superior control of the E2 release. Depending on the dose-dependent sensitivity of the physiological or pathological readout studied, this could lead to an improvement of the statistical power of in vivo experiments and thus to a reduction of the required animal number. Altogether, our data draw attention on the importance to adequately select the slow-releasing device that is the most appropriated to a specific experiment to better fulfill the 3Rs rule (Replacement, Reduction, Refinement) related to animal welfare and protection.

Loss of treatment benefit when heroin-assisted treatment is stopped after 12 months.

PURPOSE: In 2013, during a recent heroin-assisted treatment trial, participants in heroin-assisted treatment (HAT) decreased significantly more their street heroin use than participants in oral methadone treatment. After the trial, HAT was discontinued. To examine whether the treatment benefits were sustained three months after the trial, the use of street heroin by the participants was analyzed in a follow-up study. RESULTS: At the follow-up assessment, street heroin use increased in the experimental group. The two groups no longer showed a significant difference (p=0.55) in the level of street heroin use. CONCLUSION: A predetermined and forced end of HAT was followed by a significant increase in the level of street level use.

Activation of D2 autoreceptors alters cocaine-induced locomotion and slows down local field oscillations in the rat ventral tegmental area.

Psychoactive substances affecting the dopaminergic system induce locomotor activation and, in high doses, stereotypies. Network mechanisms underlying the shift from an active goal-directed behavior to a "seemingly purposeless" stereotypic locomotion remain unclear. In the present study we sought to determine the relationships between the behavioral effects of dopaminergic drugs and their effects on local field potentials (LFPs), which were telemetrically recorded within the ventral tegmental area (VTA) of freely moving rats. We used the D2/D3 agonist quinpirole in a low, autoreceptor-selective (0.1 mg/kg, i.p.) and in a high (0.5 mg/kg, i.p.) dose, and a moderate dose of cocaine (10 mg/kg, i.p.). In the control group, power spectrum analysis revealed a prominent peak of LFP power in the theta frequency range during active exploration. Cocaine alone stimulated locomotion, but had no significant effect on the peak of the LFP power. In contrast, co-administration of low dose quinpirole with cocaine markedly altered the pattern of locomotion, from goal-directed exploratory behavior to recurrent motion resembling locomotor stereotypy. This behavioral effect was accompanied by a shift of the dominant theta power toward a significantly lower (by ∼15%) frequency. High dose quinpirole also provoked an increased locomotor activity with signs of behavioral stereotypies, and also induced a shift of the dominant oscillation frequency toward the lower range. These results demonstrate a correlation between the LFP oscillation frequency within the VTA and a qualitative aspect of locomotor behavior, perhaps due to a variable level of coherence of this region with its input or output areas.

Differential effects of context on psychomotor sensitization to ethanol and cocaine.

Repeated drug injections lead to sensitization of their stimulant effects in mice, a phenomenon sometimes referred to as drug psychomotor sensitization. Previous studies showed that sensitization to cocaine is context dependent as its expression is reduced in an environment that was not paired with cocaine administration. In contrast, the effects of the test context on ethanol sensitization remain unclear. In the present study, female OF1 mice were repeatedly injected with 1.5 g/kg ethanol to test for both the effects of context novelty/familiarity and association on ethanol sensitization. A first group of mice was extensively pre-exposed to the test context before ethanol sensitization and ethanol injections were paired with the test context (familiar and paired group). A second group was not pre-exposed to the test context, but ethanol injections were paired with the test context (nonfamiliar and paired group). Finally, a third group of mice was not pre-exposed to the test context and ethanol was repeatedly injected in the home cage (unpaired group). Control groups were similarly exposed to the test context, but were injected with saline. In a second experiment, cocaine was used as a positive control. The same behavioral procedure was used, except that mice were injected with 10 mg/kg cocaine instead of ethanol. The results show a differential involvement of the test context in the sensitization to ethanol and cocaine. Cocaine sensitization is strongly context dependent and is not expressed in the unpaired group. In contrast, the expression of ethanol sensitization is independent of the context in which it was administered, but is strongly affected by the relative novelty/familiarity of the environment. Extensive pre-exposure to the test context prevented the expression of ethanol sensitization. One possible explanation is that expression of ethanol sensitization requires an arousing environment.

Correlation between ethanol behavioral sensitization and midbrain dopamine neuron reactivity to ethanol.

Repeated ethanol injections lead to a sensitization of its stimulant effects in mice. Some recent results argue against a role for ventral tegmental area (VTA) dopamine neurons in ethanol behavioral sensitization. The aim of the present study was to test whether in vivo ethanol locomotor sensitization correlates with changes in either basal- or ethanol-evoked firing rates of dopamine neurons in vitro. Female Swiss mice were daily injected with 2.5 g/kg ethanol (or saline in the control group) for 7 days and their locomotor activity was recorded. At the end of the sensitization procedure, extracellular recordings were made from dopaminergic neurons in midbrain slices from these mice. Significantly higher spontaneous basal firing rates of dopamine neurons were recorded in ethanol-sensitized mice relative to control mice, but without correlations with the behavioral effects. The superfusion of sulpiride, a dopamine D2 antagonist, induced a stronger increase of dopamine neuron firing rates in ethanol-sensitized mice. This shows that the D2 feedback in dopamine neurons is preserved after chronic ethanol administration and argues against a reduced D2 feedback as an explanation for the increased dopamine neuron basal firing rates in ethanol-sensitized mice. Finally, ethanol superfusion (10-100 mM) significantly increased the firing rates of dopamine neurons and this effect was of higher magnitude in ethanol-sensitized mice. Furthermore, there were significant correlations between such a sensitization of dopamine neuron activity and ethanol behavioral sensitization. These results support the hypothesis that changes in brain dopamine neuron activity contribute to the behavioral sensitization of the stimulant effects of ethanol.

Response to novelty and cocaine stimulant effects: lack of stability across environments in female Swiss mice.

RATIONALE: In humans, novelty/sensation seeking is seen as a personality trait with a positive relationship with addiction vulnerability. In animal studies, one of the standard procedures to model novelty seeking is the "response to novelty," i.e., the levels of locomotor activity in a new environment. In rodents, a positive correlation was demonstrated between the response to novelty and several effects of drugs, especially the locomotor stimulant effects of cocaine. OBJECTIVES: The present study was designed to test in mice whether the response to novelty is stable across environments and whether its relationship with the stimulant effects of cocaine is altered by environmental changes. Experiment 1 assessed the responses to novelty of the same mice in two different novel environments. Experiment 2 tested the correlation between response to novelty and acute stimulant effects of cocaine recorded in two distinct environments. RESULTS: The results show a weak correlation only during the first 5 min of the session between the responses to novelty measured in two distinct environments. Experiment 2 demonstrates that novelty responses and stimulant effects of cocaine are positively correlated only when both behavioral responses are measured in the same environment. In contrast, the relationship between response to novelty and acute stimulant effects of cocaine is completely lost when the behavioral responses are recorded in two different environments. CONCLUSIONS: The present results question the usual interpretation of the correlation between the response to novelty and the stimulant effects of cocaine as reflecting a relationship between two underlying individual stable characteristics.

Validation of the Marijuana Effect Expectancies Questionnaire (MEEQ) in a Non-Clinical French-Speaking Adolescent Sample.

Teenagers commonly use cannabis. Expectancies related to the effects of cannabis play an important role in its consumption and are frequently measured with the Marijuana Effect Expectancies Questionnaire (MEEQ). This study aims to assess the psychometric properties (factor structure, internal consistency reliability, criterion validity) of the French MEEQ. A sample of 1,343 non-clinical teenagers (14-18 years) were recruited to answer a self-report questionnaire; 877 of them responded twice (one-year interval). A four-factor structure was obtained: Cognitive Impairment and Negative, Relaxation and Social Facilitation, Perceptual Enhancement and Craving and Negative Behavioral Effect Expectancies. It is concluded that the French MEEQ constitutes an appropriate tool to measure cannabis effect expectancies among adolescents.