Behavioral Effects Research Articles

Effects of repeated voluntary oral consumption of synthetic delta-9-tetrahydrocannabinol on locomotor activity and cannabinoid receptor 1 expression

As cannabis legalization expands, preclinical studies continue to investigate the impact of repeated exposure to delta-9-tetrahydrocannabinol (THC), the primary psychoactive compound in the plant. With the increasing popularity of cannabis infused foods, the rise of THC in medicinal applications have also expanded. The present study addresses a critical gap in existing literature by investigating the behavioral and neurobiological effects of low-dose edible THC in a preclinical rodent model. Adult male rats were administered synthetic-THC (Dronabinol) (0.0625mg/kg, 0.125mg/kg, and 0.25mg/kg) or vehicle (sesame oil) through edible cookies, 90min prior to eight locomotor sessions. Locomotor activity significantly increased in both 0.0625mg/kg and 0.25mg/kg THC groups, indicating a dose-dependent relationship. Repeated 0.25mg/kg THC administration dose-dependently reduced cannabinoid receptor 1 expression in the hippocampus. The observed neurobiological change from low dose oral THC advances our understanding of repeated cannabis use. These findings also emphasize the importance of refining rodent models for translational relevance.

Microplastics originated from Plasmix-based materials caused biochemical and behavioral adverse effects on Daphnia magna

The implementation of advanced recycling techniques represents a key strategy for mitigating the mismanagement and the environmental impact of plastic waste. A limited array of plastic polymers can be efficiently recycled, while a notable portion of plastic waste remains unrecyclable. In Italy, this residual, heterogeneous fraction is referred to as Plasmix. Because of its complexity and non-homogeneous composition, Plasmix is primarily directed towards low-value applications. However, recent developments in laboratory-scale mechanical recycling have enabled the creation of new plastic materials from Plasmix. Prior to their application, these materials must undergo rigorous eco-safety evaluation. The present study aims to assess the potential toxicity of microplastics (MPs) from Plasmix-based materials on the freshwater crustacean Daphnia magna. Specifically, this study investigated sub-individual and individual effects induced by a 21-day exposure to different concentrations of MPs generated from the grinding of naïve and Additivated Plasmix-based materials (hereafter referred to as Px-MPs and APx-MPs, respectively). Sub-individual endpoints focused on changes in oxidative status, including the modulation of antioxidant and detoxifying enzyme activities, as well as oxidative damage, such as lipid peroxidation. Individual level endpoints included alterations in survival and reproduction. Microscopy analyses confirmed the ingestion of both Px-MPs and APx-MPs by D. magna individuals. An oxidative stress condition raised in organisms exposed to Px-MPs, whereas no effect was observed in individuals exposed to APx-MPs. Although survival was not affected, a significant impairment in reproductive output was detected at the end of exposure to all the concentrations of both MP types. These findings suggest that even low concentrations of Px-MPs and APx-MPs could negatively affect the health status of D. magna, underscoring the need for further research to complete the risk assessment of Plasmix-based materials prior to their use in consumer products.

P35-3 Internet-delivered cognitive behavioural therapy effect in breast cancer survivors: a systematic review

P35-3 Internet-delivered cognitive behavioural therapy effect in breast cancer survivors: a systematic review

Maternal ingestion of cannabidiol (CBD) in mice leads to sex-dependent changes in memory, anxiety, and metabolism in the adult offspring, and causes a decrease in survival to weaning age

RationaleThe consequences of perinatal cannabidiol (CBD) exposure are severely understudied, but are important, given its widespread use and believed safety as a natural supplement. ObjectiveThe objective of this study was to test the health, metabolic, and behavioral consequences of perinatal CBD exposure on dams and their offspring raised to adult. MethodsPrimiparous female C57BL/6 J mice were orally administered 100 mg/kg CBD in strawberry jam to expose offspring during gestation, lactation, or both using a cross-fostering design. Adult offspring were metabolically profiled using indirect calorimetry and intraperitoneal glucose tolerance testing. Adults were behaviorally phenotyped, video recorded, and mouse position tracked using DeepLabCut. ResultsCBD was detected in maternal plasma using LC-MS 10-min post consumption (34.2 ± 1.7 ng/ul) and peaked within 30 min (371.0 ± 34.0 ng/ul). Fetal exposure to CBD significantly decreased survival of the pups, and decreased male postnatal development, but did not alter litter size, maternal body weight or pup birth weight. We observed many sex-dependent effects of perinatal CBD exposure. Exposure to CBD during gestation and lactation increased meal size, caloric intake, and respiratory exchange ratio for adult male offspring, while exposure during lactation decreased fasting glucose, but had no effect on clearance. Adult female offspring exposed to CBD during lactation showed increased drink size. Perinatal CBD exposure increased obsessive compulsive- and decreased anxiety-like behaviors (marble burying, light-dark box, elevated-plus maze) in female mice, decreased long-term object memory in male mice, and had no effect on attention tasks for either sex. ConclusionsWe conclude that orally-administered CBD during pregnancy affects behavior and metabolism in a sex-dependent manner, and mice are differentially sensitive to exposure during gestation vs. lactation, or both. Because long-term changes are observed following perinatal exposure to the drug, and exposure significantly decreases survival to weaning, more research during development is warranted.

Evaluating Negotiators Who Deceptively Communicate Anger or Happiness: On the Importance of Morality, Sociability, and Competence

AbstractResearch has shown that negotiators sometimes misrepresent their emotions, and communicate a different emotion to opponents than they actually experience. Less is known about how people evaluate such negotiation tactics. Building on person perception literature, we investigated in three preregistered studies (N = 853) how participants evaluate negotiators who deceptively (vs. genuinely) communicate anger or happiness, on the dimensions of morality, sociability, and competence. Study 1 employed a buyer/seller setting, Studies 2 and 3 employed an Ultimatum Bargaining Game (UBG). In all studies, participants learned a negotiator’s (the target’s) experienced and communicated emotions (anger or happiness), before evaluating the target. Across studies, targets were evaluated lower on morality if they deceptively (vs. genuinely) communicated anger or happiness. Notably, negotiators deceptively communicating anger were evaluated lower on morality and sociability but higher on competence than those deceptively communicating happiness. Studies 2 and 3 investigated behavioral consequences by examining whether in a future negotiation participants chose the target to be their opponent or representative. Results showed that for opponents, participants preferred targets who genuinely communicated happiness (vs. anger), which was associated with their perceived morality or sociability. For representatives, participants not only preferred targets who had genuinely communicated happiness (vs. anger), but also targets who had deceptively communicated anger (vs. happiness), which was associated with their perceived competence. These findings show that when evaluating deceptive (vs. genuine) communication strategies, people distinguish between morality, sociability, and competence. The importance they attach to these dimensions is also contingent on the behavioral decisions they face.

Weighting of sensory cues reflect changing patterns of visual investment during ecological divergence in Heliconius butterflies.

Integrating information across sensory modalities enables animals to orchestrate a wide range of complex behaviours. The relative importance placed on one sensory modality over another reflects the reliability of cues in a particular environment and corresponding differences in neural investment. As populations diverge across environmental gradients, the reliability of sensory cues may shift, favouring divergence in neural investment and the weight given to different sensory modalities. During their divergence across closed-forest and forest-edge habitats, closely related butterflies Heliconius cydno and Heliconius melpomene evolved distinct brain morphologies, with the former investing more in vision. Quantitative genetic analyses suggest that selection drove these changes, but their behavioural consequences remain uncertain. We hypothesized that divergent neural investment may alter sensory weighting. We trained individuals in an associative learning experiment using multimodal colour and odour cues. When positively rewarded stimuli were presented in conflict, i.e. pairing positively trained colour with negatively trained odour and vice versa, H. cydno favoured visual cues more strongly than H. melpomene. Hence, differences in sensory weighting may evolve early during divergence and are predicted by patterns of neural investment. These findings, alongside other examples, imply that differences in sensory weighting stem from divergent investment as adaptations to local sensory environments.

Concentration- and time-dependent behavioural effects of ethanol on Lumbriculus variegatus.

Ethanol is one of the most widely used drugs in the world. Ethanol induces profound physiological and behavioural responses in invertebrate model organisms, such as Caenorhabditis elegans and Drosophila melanogaster. Lumbriculus variegatus (Annelida, Oligochaete) is an aquatic worm which shows behavioural responses to common drugs and thus is potentially useful in pharmacological research. The effects of ethanol are unknown in this organism. In this study, we examine the effects of acute exposure to ethanol (0-500 mM) on the stereotypical movements and locomotor activity of L. variegatus and examine the concentration- (0-500 mM) and time-dependent (0-210 min) effects of ethanol in L. variegatus. We show that ≥250 mM ethanol reversibly reduced the ability of tactile stimulation to elicit stereotypical movements, namely body reversal and helical swimming and locomotor activity (p < 0.05, N = 8). We also found that 2 min of exposure to ≥250 mM ethanol rapidly induces steady-state hypokinesis (p < 0.05, N = 11) and confirm ethanol absorption into L. variegatus tissues. Additionally, we also observed acute ethanol tolerance after 150 min of exposure to 500 mM ethanol (p < 0.05, N = 24). This study is the first to report the behavioural effects of ethanol in L. variegatus. Our results show that this is a model organism for use in ethanol studies, providing further evidence for its utility in pharmacological research.

Physiologic and behavioral effects of long-acting subcutaneous and transdermal buprenorphine in rats.

To investigate thermoregulation, thermal antinociception, food/kaolin intake, fecal output, and behavior following long-acting buprenorphine preparations in rats. 8 adult male rats (Rattus norvegicus) were administered long-acting SC buprenorphine (SB; 0.65 mg/kg), transdermal buprenorphine (TB; 10 mg/kg), and controls in a randomized, cross-over design. Body temperature, self-injury, sedation, food/kaolin intake, fecal output, and thermal withdrawal latencies were measured 1, 4, 8, 12, 24, 48, and 72 hours posttreatment. Data analysis was performed with mixed linear models. Self-injury was present between 1 and 12 hours and 4 and 12 hours following TB and SB, respectively; sedation was associated with TB at 12 to 24 hours. Withdrawal latencies were longer in both TB and SB groups than in the control group. Food intake decreased with time in all groups but was significantly lower 24 to 48 hours after TB and 24 to 72 hours after SB versus controls. Kaolin intake decreased from baseline 48 to 72 hours in the control group. Fecal output decreased from baseline 24 to 72 hours in all groups but was significantly lower than controls 24 hours following TB and 24 to 48 hours in SB. Body temperature increased from baseline at 1 hour, 1 to 12 hours, and 1 to 24 hours in the control, TB, and SB groups, respectively, and was significantly higher than the control group 1 to 72 hours following TB and 4 to 24 hours after SB. Transdermal buprenorphine and SB in normal rats produced antinociception, self-injurious behavior, hyperthermia, and decreased food/fecal output. Although these buprenorphine preparations may produce antinociception, untoward effects such as hyperthermia, self-injurious behavior, and reduced food intake/fecal output may be seen.

Aquatic hazard and risk posed by four pesticides detected in waterways discharging to the Great Barrier Reef, Australia: Part 2. Hazard and risk assessment

Pesticide active ingredients (PAIs) are regularly detected in the rivers, creeks, wetlands, and inshore waterways that discharge to the Great Barrier Reef (GBR) lagoon. Pesticide active ingredients detected above ecologically protective concentrations may pose a hazard and risk to aquatic species. The ability to assess this hazard and risk is reliant on the availability of water quality guidelines, which are only available for a limited number of PAIs detected in GBR catchment waterways. Unendorsed guideline values, known as ecotoxicity threshold values (ETVs) were developed in part one of this study for active ingredients in two fungicides (4-hydroxychlorothalonil (fungicide degradate) and carbendazim) and two insecticides (dimethoate and methoxyfenozide) that are commonly detected in GBR catchment waterways. In the current study, the hazard and risk posed by these PAIs was assessed by comparing the ETVs to environmental monitoring data from the Great Barrier Reef Catchment Loads Monitoring Program. Exceedances of the concentrations that should protect 99 % of aquatic species (i.e., PC99) were observed for all four pesticides. Detected concentrations of 4-hydroxychlorothalonil, carbendazim and methoxyfenozide exceeded the PC95 ETV, however no exceedances of the PC95 were observed for dimethoate. The hazard quotient (HQ) method was used to identify high hazard sites across the GBR catchment area. In total, six sites were identified as having concentrations that exceeded the PC95 ETVs. For 4-hydroxychlorothalonil, the risk to aquatic species based on the 95th percentile concentrations ranged from 3 to 13 %, 1 to 8 % for carbendazim and 2 to 8 % for methoxyfenozide. Detected concentrations of carbendazim were two orders of magnitude higher than concentrations that are reported to induce behavioural effects in some fish species. Considering that detected concentrations of three of the four PAIs individually pose a potential risk to aquatic species, their contributions to pesticide mixture toxicity should be further assessed.

Nomophobia syndrome and its impact on morale and behavior change in early childhood

Nomophobia has become a prevalent issue which affects individuals today. This leads many to feel constantly connected to their devices. The term, derived from "No Mobile Phone Phobia," describes an excessive reliance on gadgets. This psychological condition is recognized as a global psychosocial phenomenon that influences mobile phone users and affects their morals and behavior. Alarmingly, this issue has also emerged among young children, with many preschoolers showing signs of addiction. This study is aimed at exploring the effects of nomophobia on early childhood, focusing on its moral and behavioral consequences in daily life. The study employed a qualitative case study approach and it involved two 5-year-old children. Data were collected through observations and unstructured interviews with their parents. The findings indicated that excessive gadget used in early childhood could significantly alter children's morals and behaviors. This was primarily due to insufficient parental supervision of their app usage. The study emphasized the need for intervention from adults, including both parents and teachers, who are the closest guardians to children in monitoring smartphone usage. These collaborative preventive measures to monitor and mitigate the negative impacts of smartphone usage are important to do. Future studies for exploring nomophobia in early childhood contexts are encouraged to delve deeper into the surrounding events and circumstances that affect children.

Mical1 deletion in tyrosinase expressing cells affects mouse running gaits.

Neuronal development is a highly regulated process that is dependent on the correct coordination of cellular responses to extracellular cues. In response to semaphorin axon guidance proteins, the MICAL1 protein is stimulated to produce reactive oxygen species that oxidize actin on specific methionine residues, leading to filamentous actin depolymerization and consequent changes in neuronal growth cone dynamics. Crossing genetically modified mice homozygous for floxed Mical1 (Mical1fl/fl) alleles with transgenic mice expressing Cre recombinase under the control of a tyrosinase gene enhancer/promoter (Tyr::Cre) enabled conditional Mical1 deletion. Immunohistochemical analysis showed Mical1 expression in the cerebellum, which plays a prominent role in the coordination of motor movements, with reduced Mical1 expression in Mical1fl/fl mice co-expressing Tyr::Cre. Analysis of the gaits of mice running on a treadmill showed that both male and female Mical1fl/fl, Tyr::Cre mutant mice had significant alterations to their striding patterns relative to wild-type mice, although the specific aspects of their altered gaits differed between the sexes. Additional motor tests that involved movement on a rotating rod, descending a vertical pole, or crossing a balance beam did not show significant differences between the genotypes, suggesting that the effect of the Mical1fl/fl, Tyr::Cre genetic modifications was only manifested during specific highly coordinated movements that contribute to running. These findings indicate that there is a behavioral consequence in Mical1fl/fl, Tyr::Cre mutant mice that affects motor control as manifested by alterations in their gait.

A Study on How Social Media FOMO (Fear of Missing Out) Impacts the Gen Z Audience

Generation Z, or Gen Z, refers to people born between 1995 and 2010, often known as "zoomers," the first generation to fully embrace the internet. This paper focuses on the impact of socialmedia-induced Fear ofMissing Out (FOMO) on Generation Z, blending with the characteristics of digital nativity and extensive engagement with social media platforms. Fear of Missing Out, or FOMO, was uniquely introduced in 2004 with the rise of social networking sites. It centers on anxiety and how, for Gen Z, this plays a pivotal role in making one feel absent from rewarding experiences. This study delves into the effects on mental health, psychological well-being, self-esteem, and life satisfaction. It explores social media analytics regarding usage, compulsive checking, behavioural consequences, following trends, and real-life social interactions. The findings highlight the need for strategies to mitigate FOMO's adverse effects, promoting healthier social media habits and fostering a more balanced approach to digital consumption.

"Hot" affect-related aspects in emotional information processing: The role of facial muscle responses in the direct and indirect processing of emotion categories.

The present study investigated the involvement of facial muscle responses in the indirect and direct processing of emotional facial expressions. Five discrete emotion categories were used, and we assessed both facial muscle and behavioral responses on a trial-by-trial basis. Experiment 1 tested facial muscle activation of clearly visible stimuli in an emotion categorization task. We observed emotion-specific facial muscle responses and corresponding behavioral categorization effects, providing evidence for the specificity of facial muscle activation. By contrast, under masked indirect presentation conditions in which emotional facial expressions were presented as primes in an emotion misattribution procedure, a specific pattern of emotion-congruent and cross-category behavioral misattributions was observed (in line with Rohr et al., 2015, 2018). Multilevel analyses in Study 2 suggest that an emotional reaction feeds into the behavioral decision, as indicated by differential activation of the frontalis lateralis in response to angry faces. Thus, the present study provides evidence that facial muscle responses contribute to behavioral decisions under masked indirect processing conditions. The different pattern of effects in both studies suggests that facial muscle responses index different processes, depending on the processing conditions: sensorimotor simulation in direct processing conditions and emotional reactions in masked indirect processing conditions. We discuss the implications for models that aim to account for facial muscle activity in response to emotional facial expressions. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

BNST CRF receptor type 1 modulates mechanical hypersensitivity induced by adolescent alcohol exposure in adult female mice.

Alcohol exposure during adolescence has been linked to long-lasting behavioral consequences, contributing to the development of alcohol use disorder. Negative affect and chronic pain during alcohol withdrawal are critical factors influencing problematic alcohol use and relapse. Our previous research demonstrated that adolescent intermittent ethanol (AIE) vapor exposure elicits sex-specific negative affect-like behavior in adult mice following stress exposure. Additionally, AIE induces persistent mechanical hypersensitivity, which is accompanied by increased activation of corticotropin-releasing factor receptor type 1 (CRFR1) neurons in the dorsolateral bed nucleus of the stria terminalis (dlBNST). This study extends previous work by investigating plasma corticosterone levels and CRFR1 protein expression in the dlBNST following restraint stress exposure in adult mice with an AIE history. We also aim to explore the role of dlBNST CRFR1 signaling in mediating negative affect-like behavior and mechanical hypersensitivity. Female mice exhibited elevated plasma corticosterone levels compared to males following restraint stress. Moreover, females with AIE history showed higher expression of CRFR1 protein in the dlBNST compared to air controls. Antagonism of CRFR1 in the dlBNST blocked AIE-induced mechanical hypersensitivity in adult females but did not affect stress-induced negative affect-like behavior. In alcohol-naïve females, intra-dlBNST administration of a CRFR1 agonist induced mechanical hypersensitivity. These findings provide new insights into the neurobiological mechanisms underlying stress-induced negative affect and pain-related behavior, both influenced by a history of adolescent alcohol exposure. The results suggest that CRFR1 antagonists warrant further investigation for their potential in addressing alcohol-related chronic pain.

Personality and health behavior changes after pulmonary rehabilitation: A longitudinal observational study.

Pulmonary rehabilitation (PR) is the gold standard treatment for improving the health status of individuals with chronic respiratory diseases (CRD). However, to achieve lasting results, the adoption and maintenance of a physically active lifestyle are necessary. Unfortunately, the trajectories of change in physical activity (PA) and sedentary behavior (SB) following PR are marked by a high degree of heterogeneity between patients. This study aimed to better understand the factors underlying this variability by investigating the role played by the personality as defined by the five-factor model. Eighty eight CRD patients were assessed on personality upon PR admission (Time 1). PA and SB were assessed at Time 1 and 6 months post-PR (Time 2) using questionnaires. Multiple regression analyses revealed that "healthy neuroticism" is associated with an increase in PA 6 months after PR (β = .20, p < .05) independently of the PA at Time 1. A high level of neuroticism, when it is paired with a low level of conscientiousness, is related to an increase in SB 6 months after PR (β = -.20, p < .01), when the SB and exercise tolerance at Time 1 were controlled for. These findings highlight that investigating the interaction between personality traits is relevant to a better understanding of the interindividual differences in changes in PA and SB after PR in patients with CRD. The behavioral effects of PR could be improved if patients' personality traits were taken into account in the design of behavior-change interventions. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Partial chemogenetic inhibition of the locus coeruleus due to heterogeneous transduction of noradrenergic neurons preserved auditory salience processing in wild-type rats.

The acoustic startle reflex (ASR) and prepulse inhibition of the ASR (PPI) assess the efficiency of salience processing, a fundamental brain function that is impaired in many psychiatric conditions. Both ASR and PPI depend on noradrenergic transmission, yet the modulatory role of the locus coeruleus (LC) remains controversial. Clonidine (0.05 mg/kg, i.p.), an alpha2-adrenoreceptor agonist, strongly reduced the ASR amplitude. In contrast, chemogenetic LC inhibition only mildly suppressed the ASR and did affect the PPI in virus-transduced rats. The canine adenovirus type 2 (CAV2)-based vector carrying a gene cassette for the expression of inhibitory receptors (hM4Di) and noradrenergic cell-specific promoter (PRSx8) had high cell-type specificity (94.4±3.1%) but resulted in heterogeneous virus transduction of DbH-positive LC neurons (range: 9.2-94.4%). Clozapine-N-oxide (CNO; 1mg/kg, i.p.), a hM4Di actuator, caused the firing cessation of hM4Di-expressing LC neurons, yet complete inhibition of the entire population of LC neurons was not achieved. Case-based immunohistochemistry revealed that virus injections distal (> 150μm) to the LC core resulted in partial LC transduction, while proximal (< 50 μm) injections caused neuronal loss due to virus neurotoxicity. Neither the ASR nor PPI differed between the intact and virus-transduced rats. Our results suggest that a residual activity of virus-non-transduced LC neurons might have been sufficient for mediating an unaltered ASR and PPI. Our study highlights the importance of a case-based assessment of the virus efficiency, specificity, and neurotoxicity for targeted cell populations and of considering these factors when interpreting behavioral effects in experiments employing chemogenetic modulation.

The effects of amphetamine exposure on stress susceptibility in mice

Substance use disorders (SUDs) and their many psychiatric comorbidities, including major depression and anxiety disorders, are characterized by significant sex differences. Although the causes of SUDs and their psychiatric comorbidities remain unknown, stress has been heavily implicated in their etiology. Indeed, one leading hypothesis regarding the basis of clinically observed sex differences in psychopathology argues that differences in stress susceptibility and stress exposure play key roles. Consistent with this, differences in stress susceptibility and reactivity in females compared to males have been documented across multiple species. A wide range of environmental, genetic, and epigenetic factors are also thought to impact stress susceptibility, but whether there are sex differences in the effects of specific susceptibility factors remains understudied. Preclinical work suggests that a history of cocaine exposure can increase susceptibility to stress in males, but whether similar effects occur in females following stimulant exposure has not been established. The current work examined the impact of repeated amphetamine administration on subsequent susceptibility to mild sub-chronic stress in male and female mice. In addition to examining behavior, potential sex differences in the effects of stress and amphetamine on the expression of several genes were evaluated. Our results reveal several significant sex differences in the behavioral effects of amphetamine and stress in the elevated plus maze, forced swim test, and novelty-suppressed feeding test. However, in contrast to our initial hypothesis, a history of amphetamine did not lead to an overall increase in stress susceptibility across multiple tests in males or females.

The Neurophysiological Costs of Learning in a Noisy Classroom: An Ecological Virtual Reality Study.

Many real-life situations can be extremely noisy, which makes it difficult to understand what people say. Here, we introduce a novel audiovisual virtual reality experimental platform to study the behavioral and neurophysiological consequences of background noise on processing continuous speech in highly realistic environments. We focus on a context where the ability to understand speech is particularly important: the classroom. Participants (n = 32) experienced sitting in a virtual reality classroom and were told to pay attention to a virtual teacher giving a lecture. Trials were either quiet or contained background construction noise, emitted from outside the classroom window. Two realistic types of noise were used: continuous drilling and intermittent air hammers. Alongside behavioral outcomes, we measured several neurophysiological metrics, including neural activity (EEG), eye-gaze and skin conductance (galvanic skin response). Our results confirm the detrimental effect of background noise. Construction noise, and particularly intermittent noise, was associated with reduced behavioral performance, reduced neural tracking of the teacher's speech and an increase in skin conductance, although it did not have a significant effect on alpha-band oscillations or eye-gaze patterns. These results demonstrate the neurophysiological costs of learning in noisy environments and emphasize the role of temporal dynamics in speech-in-noise perception. The finding that intermittent noise was more disruptive than continuous noise supports a "habituation" rather than "glimpsing" hypothesis of speech-in-noise processing. These results also underscore the importance of increasing the ecologically relevance of neuroscientific research and considering acoustic, temporal, and semantic features of realistic stimuli as well as the cognitive demands of real-life environments.

Falling off the Social Ladder: Longitudinal Behavioral and Mental Health Consequences of Desiring Higher Popularity and Experiencing Popularity Status Insecurity

Falling off the Social Ladder: Longitudinal Behavioral and Mental Health Consequences of Desiring Higher Popularity and Experiencing Popularity Status Insecurity

Temporal changes in HIV-related stigma and sexual behaviours: An examination of 22 African countries.

ABSTRACTDespite non-trivial success against the HIV epidemic, health experts in Sub-Saharan Africa (SSA) remain concerned about new infections, stigma attitudes, and increasing rates of higher-risk sexual behaviours (HRSBs). Although this concern has produced voluminous scholarship on the behavioural consequences of belonging to stigmatised populations, scholars have only recently examined the behavioural consequences of holding stigmatising attitudes. Existing work generally finds a positive relationship between stigmatising beliefs and the practice of HRSBs. Yet, it is unknown whether this relationship has changed for countries over the past two decades. We fill this gap using Demographic and Health Survey data from 22 SSA countries. We first find that in most countries, the practice of HRSBs has increased, while stigma beliefs have become more tolerant. Second, the relationship between stigma beliefs and HRSBs changed in only six countries: Nigeria, Kenya, Mozambique, Sierra Leone, Ethiopia, and Lesotho. It changed from non-existent or negative to positive in Nigeria, Kenya, Mozambique, and Ethiopia, but non-existent to negative in Sierra Leone. In Lesotho, the positive association weakened over time. These findings highlight the importance of social and epidemic contexts when considering how stigma impacts sexual behaviours and HIV rates in SSA.