An investigation of the experience of control through the sense of agency in people with obsessive-compulsive disorder: a review and meta-analysis.

The construct of sense of agency (SoA) has proven useful for understanding mechanisms underlying obsessive-compulsive disorder (OCD) phenomenology, especially in explaining the apparent dissociation in OCD between actual and perceived control over one's actions. Paradoxically, people with OCD appear to experience both diminished SoA (feeling unable to control their actions) and inflated SoA (having "magical" control over events). The present review investigated the extent to which the SoA is distorted in OCD, in terms of both implicit (ie, inferred from correlates and outcomes of voluntary actions) and explicit (ie, subjective judgment of one's control over an outcome) measures of SoA. Our search resulted in 15 studies that met the criteria for inclusion in a meta-analysis, where we also examined the potential moderating effects of the type of measure (explicit versus implicit) and of the actual control participants had over the outcome. We found that participants with OCD or with high levels of OCD symptoms show lower implicit measures of SoA and at the same time tend to overestimate their control in situations where they do not actually have it. Together, these findings support the hypothesized dissociation in OCD between actual and perceived control over one's actions.

Cocaine self-administration behavior is associated with subcortical and cortical morphometry measures in individuals with cocaine use disorder.

Background: Individual differences in gray-matter morphometry in the limbic system and frontal cortex have been linked to clinical features of cocaine use disorder (CUD). Self-administration paradigms can provide more direct measurements of the relationship between the regulation of cocaine use and gray-matter morphometry when compared to self-report assessments.Objectives: Our goal was to investigate associations with self-administration behavior in subcortical and cortical brain regions. We hypothesized the number of cocaine infusions self-administered would be correlated with gray-matter volumes (GMVs) in the striatum, amygdala, and hippocampus. Due to scarcity in human studies, we did not hypothesize subcortical directionality. In the frontal cortex, we hypothesized thickness would be negatively correlated with self-administered cocaine.Methods: We conducted an analysis of cocaine self-administration and structural MRI data from 33 (nFemales = 10) individuals with moderate-to-severe CUD. Self-administration lasted 60-minutes and cocaine (8, 16, or 32 mg/70 kg) was delivered on an FR1 schedule (5-minute lockout). Subcortical and cortical regression analyses were performed that included combined bilateral regions and age, experimental variables and use history as confounders.Results: Self-administered cocaine infusions were positively associated with caudal GMV (b = 0.18, p = 0.030) and negatively with putamenal GMV (b = -0.10, p = 0.041). In the cortical model, infusions were positively associated with insular thickness (b = 0.39, p = 0.008) and women appeared to self-administer cocaine more frequently (b = 0.23, p = 0.019).Conclusions: Brain morphometry features in the striatum and insula may contribute to cocaine consumption in CUD. These differences in morphometry may reflect consequences of prolonged use, predisposed vulnerability, or other possibilities.Clinical Trial Numbers: NCT01978431; NCT03471182.

The Dose-Dependent Effect of Fractionated γ-Radiation on Anxiety-Like Behavior in Neonatal Mice.

High doses of ionizing radiation are the risk factor of cognitive dysfunction and anxiety disorders developing in humans and experimental animals. However, the data on the effect of low doses, especially in case of chronic or fractionated exposure, is limited and contradictory. Here we studied the effect of fractionated γ-radiation at cumulative doses of 0.1, 1, and 5 Gy on the parameters of the anxiety-like behavior in neonatal C57BL/6 mice. The anxiety was evaluated using the marble burying test and elevated plus maze. Fractionated irradiation resulted in dose-dependent changes in mouse behavior: the low dose caused an increase in anxiety, wherein the dose raise led to the decrease in anxiety-like behavior indicators compared to non-irradiated animals.

Mapping the neuroanatomical abnormalities in a phenotype of male compulsive rats.

Compulsivity is considered a transdiagnostic dimension in obsessive-compulsive and related disorders, characterized by heterogeneous cognitive and behavioral phenotypes associated with abnormalities in cortico-striatal-thalamic-cortical circuitry. The present study investigated the structural morphology of white and gray matter in rats selected for low- (LD) and high- (HD) compulsive drinking behavior on a schedule-induced polydipsia (SIP) task. Regional brain morphology was assessed using ex-vivo high-resolution magnetic resonance imaging (MRI). Voxel-based morphometry of segmented MRI images revealed larger white matter volumes in anterior commissure and corpus callosum of HD rats compared with LD rats. HD rats also showed significantly larger regional volumes of dorsolateral orbitofrontal cortex, striatum, amygdala, hippocampus, midbrain, sub-thalamic nucleus, and cerebellum. By contrast, the medial prefrontal cortex was significantly smaller in HD rats compared with LD rats with no significant group differences in whole brain, ventricular, or cerebrospinal fluid volumes. These findings show that limbic cortico-basal ganglia structures implicated in impulse control disorders are distinct in rats that are vulnerable to develop compulsive behavior. Such abnormalities may be relevant to the etiology of compulsive disorders in humans.

Cognitive impairment in hoarding disorder: a systematic review.

OBJECTIVE: In the present study, we aimed to perform a systematic review evaluating the cognitive performance of patients with hoarding disorder (HD) compared with controls. We hypothesized that HD patients would present greater cognitive impairment than controls. METHODS: A systematic search of the literature using the electronic databases MEDLINE, SCOPUS, and LILACS was conducted on May 2020, with no date limit. The search terms were "hoarding disorder," "cognition," "neuropsychology," "cognitive impairment," and "cognitive deficit." We included original studies assessing cognitive functioning in patients with HD. RESULTS: We retrieved 197 studies initially. Of those, 22 studies were included in the present study. We evaluated 1757 patients who were 41 to 72 years old. All selected studies comprised case-control studies and presented fair quality. Contrary to our hypothesis, HD patients showed impairment only in categorization skills in comparison with controls, particularly at confidence to complete categorization tasks. Regarding attention, episodic memory, working memory, information-processing speed, planning, decision-making, inhibitory control, mental flexibility, language, and visuospatial ability, HD patients did not show impairment when compared with controls. There is a paucity of studies on social cognition in HD patients, although they may show deficits. The impact of emotion in cognition is also understudied in HD patients. CONCLUSION: Except for categorization skills, the cognitive performance in HD patients does not seem to be impaired when compared with that in controls. Further work is needed to explore social cognition and the impact of emotion in cognitive performance in HD patients.

Long-term stability in obsessive thoughts and compulsive behavior in the general population: a longitudinal study in Sweden.

OBJECTIVE: Obsessive thoughts and compulsive behavior and their related disorder Obsessive-Compulsive Disorder (OCD) commonly occur in the general population. Clinical populations indicate a high level of stability, although there are few longitudinal studies in the general population. The recommended drug treatments are SSRIs/TCAs. However, there are few long-term follow up studies. The goal of this study was to 1) examine the occurrence and stability of obsessions, compulsions, and OCD in a longitudinal population-based survey, 2) investigate the use of SSRI and TCA and the potential effect on symptoms. METHODS: A ten-year longitudinal general population in Stockholm was used (2000 and 2010, n = 5650) Obsessional washing, checking, intrusive unpleasant thoughts and the level of suffering due to these symptoms were measured by self-report. Information on use of SSRIs and TCAs by these individuals was obtained from registers. Stability was examined using contingency tables and multinomial logistic regression. RESULTS: At baseline, 2.1, 11.7 and 11.9% reported obsessional washing, checking and intrusive thoughts. A total of 5% reported considerable suffering from these (i.e. OCD). Based on psychiatric interview only 0.4% had OCD. Ten years later a quarter of OCD cases were still classified as having OCD, one quarter reported any obsessive or compulsive symptom and half were classified as symptom-free. Treatment receipt was low and controlling for medication did not change the stability. CONCLUSION: Obsessive thoughts and compulsive behavior are common and stable. While this group is potentially undertreated, there is no indication that those treated display a different pattern of recovery.

Clinical profile of schizophrenia comorbid with obsessive-compulsive symptoms: A comparative study.

OBJECTIVE: Describe and compare the clinical profile of schizophrenic patients with and without obsessive-compulsive symptoms and obsessive-compulsive disorder (OCD) patients. METHODS: A descriptive and analytical cross-sectional study was carried out at the psychiatry department of Hassan II University Hospital in Fez over 12 months to compare three groups of patients: "schizo-obsessive" (n=32), "schizophrenia" (n=34), and "OCD" (n=46). All participants (n=112) were assessed using the mini-international neuropsychiatric interview (MINI), the Yale-Brown obsessive-compulsive scale (Y-BOCS), the Brown assessment of beliefs scale (BABS), the Hamilton anxiety rating scale (HAM-A), the Beck's depression inventory (BDI-II), the positive and negative syndrome scale (PANSS), and the clinical global impressions-severity scale (CGI-S). RESULTS: The "schizo-obsessive" group differed from the "schizophrenia" group in: more severe psychotic symptoms (mean=64.16±17.049, P<0.001), higher anxiety (mean=8.87±5,655, P<0.001) and depression (mean=7.50±5.989, P<0.001) scores, more prevalent suicide attempts (46.9%), higher illness severity score (mean=5.13±1.157, P=0.02), and more professional disinsertion (78.1%). The "schizo-obsessive" group (mean= 14.47±3.388) had significantly poor insight (P<0.001) compared to the "OCD" group (mean= 8.35±4.542). There were similarities in the obsessive and compulsive themes between the "schizo-obsessive" and the "OCD" groups, with no significant difference of severity (P=0.26). CONCLUSION: A careful assessment of obsessive symptomatology is essential in schizophrenia for better patient management and prognosis.

Frequency of Impulsive-Compulsive Behavior and Associated Psychological Factors in Parkinson's Disease: Lack of Control or Too Much of It?

Background and Objectives: Impulse Control Disorders (ICDs) including pathological gambling, hypersexuality, compulsive eating, compulsive buying, and other related behaviors are well-known distinct non-motor symptoms in Parkinson's Disease (PD). Some large-scale studies present a prevalence of at least 10%, however, there are other reports providing much higher rates. The majority of the conducted studies investigating ICDs focus mainly on pharmacological factors, however, from a psychological perspective, there is yet enough room for investigation. In order to address the above issues, we designed a two-part study. Materials and Methods: First, we aimed to identify the incidence of ICD and related behaviors in a cohort of 892 Greek PD patients. Second, we administered a comprehensive battery of psychometric tools to assess psychological factors such as personality dimensions, quality of life, defenses, coherence, and resilience as well as to screen general cognitive capacity in PD patients with ICD manifestations. Results: With regard to the first part, we identified ICD manifestations in 12.4% of the patients. Preliminary findings from the second part indicate elevated activity, rather than impulsivity, as well as interrelations between several variables, including measures of activity, coping mechanisms, and quality of life. Conclusions: We present a working hypothesis for the contribution of high activity channeled to specific behavioral patterns through specific coping mechanisms, concerning the emergence of ICDs and related behaviors in PD, and further stress the importance of compulsivity rather than impulsivity in this process.

NMR-based Metabolomics and Fatty Acid Profiles to Unravel Biomarkers in Preclinical Animal Models of Compulsive Behavior.

Compulsivity is a key manifestation of inhibitory control deficit and a cardinal symptom of psychopathological conditions such as obsessive-compulsive and attention-deficit hyperactivity disorders, in which metabolic alterations have raised attention as putative biomarkers for early identification. The present study assessed the metabolic profile in a preclinical model of a compulsive phenotype of rats. We used the schedule-induced polydipsia (SIP) method to classify male Wistar rats into high drinkers (HDs) or low drinkers (LDs) according to their compulsive drinking rate developed by exposure to a fixed-time 60 s (FT-60) schedule of reinforcement with water available ad libitum during 20 sessions. Before and after SIP, blood samples were collected for subsequent serum analysis by nuclear magnetic resonance spectroscopy coupled to multivariate analysis. Although no differences existed in the pre-SIP set, the compulsive drinking behavior induced remarkable metabolic alterations: HD rats selected by SIP exhibited a hyperlipidemic, hypoglycemic, and hyperglutaminergic profile compared with their low-compulsive counterparts. Interestingly, these alterations were not attributable to the mere exposure to reward pellets because a control experiment did not show differences between HDs and LDs after 20 sessions of pellet consumption without intermittent reinforcement. Our results shed light toward the implication of dietary and metabolic factors underpinning the vulnerability to compulsive behaviors.

Socioemotional deficit and HPA axis time response in high compulsive rats selected by schedule-induced polydipsia.

Compulsivity is a failure to stop an ongoing behavior that has become inappropriate to the situation and is recognized as a transdiagnostic trait present in different neuropsychiatric disorders. The implication of motivation and emotion, as well as the stress response in compulsive population has not been fully understood. We assessed the motivation to reward and cues, the emotional response in different contexts and the hypothalamic-pituitary-adrenal (HPA) axis response in rats selected by a preclinical model of compulsive behavior. Firstly, high (HD) or low (LD) drinkers were selected according to their drinking behavior on schedule-induced polydipsia (SIP). Then, we assessed motivation by the propensity to attribute incentive salience to rewards on Pavlovian Conditioned Approach (PavCA) and motivation to gain reward on Progressive Ratio Schedule of Reinforcement (PRSR). Emotion was measured by Social Dominance on the Tube Test (SDTT) and emotional memory on Passive Avoidance (PA). Plasma corticosterone (CORT) levels in response to SIP were assessed. HD rats showed a socioemotional deficit by fewer victories on the SDTT, and an increased latency to enter the dark compartment on the PA. No differences were found between groups regarding to motivational assessment. Moreover, HD rats revealed a blunted time response in the increase of CORT levels at 45 min after SIP compared to LD rats. The findings show that the compulsive phenotype of HD rats exhibit less social dominance, more resistance to extinction and a differential CORT time response to SIP. These findings may contribute to highlight the relevance of assessing socioemotional behaviors and stress response for a better characterization of the vulnerability to compulsive spectrum disorders.

Dysfunctional Brain Reward System in Child Obesity.

Eating habits leading to obesity may reflect nonhomeostatic behavior based on excessive immediate-reward seeking. However, it is currently unknown to what extent excess weight is associated with functional alterations in the brain's reward system in children. We tested the integrity of reward circuits using resting-state functional connectivity magnetic resonance imaging in a population of 230 children aged 8-12 years. The major components of the reward system were identified within the ventral striatum network defined on the basis of the nucleus accumbens connectivity pattern. The functional structure of the cerebral cortex was characterized using a combination of local functional connectivity measures. Higher body mass index was associated with weaker connectivity between the cortical and subcortical elements of the reward system, and enhanced the integration of the sensorimotor cortex to superior parietal areas relevant to body image formation. Obese children, unlike WHO-defined overweight condition, showed functional structure alterations in the orbitofrontal cortex and amygdala region similar to those previously observed in primary obsessive-compulsive disorder and Prader-Willi syndrome associated with obsessive eating behavior. Results further support the view that childhood obesity is not simply a deviant habit with restricted physical health consequences but is associated with reward system dysfunction characterizing behavioral control disorders.

Compulsive drug use is associated with imbalance of orbitofrontal- and prelimbic-striatal circuits in punishment-resistant individuals.

Substance use disorders (SUDs) impose severe negative impacts upon individuals, their families, and society. Clinical studies demonstrate that some chronic stimulant users are able to curtail their drug use when faced with adverse consequences while others continue to compulsively use drugs. The mechanisms underlying this dichotomy are poorly understood, which hampers the development of effective individualized treatments of a disorder that currently has no Food and Drug Administration-approved pharmacological treatments. In the present study, using a rat model of methamphetamine self-administration (SA) in the presence of concomitant foot shocks, thought to parallel compulsive drug taking by humans, we found that SA behavior correlated with alterations in the balance between an increased orbitofrontal cortex-dorsomedial striatal "go" circuit and a decreased prelimbic cortex-ventrolateral striatal "stop" circuit. Critically, this correlation was seen only in rats who continued to self-administer at a relatively high rate despite receiving foot shocks of increasing intensity. While the stop circuit functional connectivity became negative after repeated SA in all rats, "shock-resistant" rats showed strengthening of this negative connectivity after shock exposure. In contrast, "shock-sensitive" rats showed a return toward their baseline levels after shock exposure. These results may help guide novel noninvasive brain stimulation therapies aimed at restoring the physiological balance between stop and go circuits in SUDs.

Neurophysiological Correlates of Trait Impulsivity in Parkinson's Disease.

BACKGROUND: Impulsivity is common in people with Parkinson's disease (PD), with many developing impulsive compulsive behavior disorders (ICB). Its pathophysiological basis remains unclear. OBJECTIVES: We aimed to investigate local field potential (LFP) markers of trait impulsivity in PD and their relationship to ICB. METHODS: We recorded subthalamic nucleus (STN) LFPs in 23 PD patients undergoing deep brain stimulation implantation. Presence and severity of ICB were assessed by clinical interview and the Questionnaire for Impulsive-Compulsive Disorders in PD-Rating Scale (QUIP-RS), whereas trait impulsivity was estimated with the Barratt Impulsivity Scale (BIS-11). Recordings were obtained during the off dopaminergic states and the power spectrum of the subthalamic activity was analyzed using Fourier transform-based techniques. Assessment of each electrode contact localization was done to determine the topography of the oscillatory activity recorded. RESULTS: Patients with (n = 6) and without (n = 17) ICB had similar LFP spectra. A multiple regression model including QUIP-RS, BIS-11, and Unified PD Rating Scale-III scores as regressors showed a significant positive correlation between 8-13 Hz power and BIS-11 score. The correlation was mainly driven by the motor factor of the BIS-11, and was irrespective of the presence or absence of active ICB. Electrode contact pairs with the highest α power, which also correlated most strongly with BIS-11, tended to be more ventral than contact pairs with the highest beta power, which localize to the dorsolateral motor STN. CONCLUSIONS: Our data suggest a link between α power and trait impulsivity in PD, irrespective of the presence and severity of ICB. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Understanding athletic and exercise identity in relation to disordered eating behaviors.

PURPOSE: This study investigated the associations between athletic and exercise identities and a range of disordered eating and exercise behaviors. METHOD: Study 1 (N = 441; 53.5% female) included online questionnaires of athletic identity and disordered eating behaviors, anthropometrics, and demographic information. Study 2 (N = 225; 50.2% female) added measures of: exercise identity, exercise behaviors, and a broader measure of disordered eating behaviors. Multiple linear regressions were used to test hypotheses. Dominance analysis was used in Study 2 to determine the unique variance accounted for by each predictor. RESULTS: Controlling for body mass index (BMI), age, and sex, athletic identity was not significantly associated with disordered eating in Study 1 (ps > 0.039) but was significantly associated with lower cognitive restraint in Study 2 (p = 0.012). In Study 2, stronger exercise identity was significantly associated with more cognitive restraint (p < 0.001), more body dissatisfaction (p = 0.016), more compulsive exercise (p < 0.001), and more positive and healthy exercise (p < 0.001), after controlling for BMI, age, sex, and athletic identity. Dominance analyses suggested that exercise identity was more strongly associated with these outcomes than athletic identity. CONCLUSION: Exercise identity, but not athletic identity, may be an important risk factor for disordered eating and exercise behaviors in broad populations. LEVEL OF EVIDENCE: Level IV, results from uncontrolled trial.

GBA-Related Parkinson's Disease: Dissection of Genotype-Phenotype Correlates in a Large Italian Cohort.

BACKGROUND: Variants in GBA are the most common genetic risk factor for Parkinson's disease (PD). The impact of different variants on the PD clinical spectrum is still unclear. OBJECTIVES: We determined the frequency of GBA-related PD in Italy and correlated GBA variants with motor and nonmotor features and their occurrence over time. METHODS: Sanger sequencing of the whole GBA gene was performed. Variants were classified as mild, severe, complex, and risk. ß-glucocerebrosidase activity was measured. The Kaplan-Meier method and Cox proportional hazard regression models were performed. RESULTS: Among 874 patients with PD, 36 variants were detected in 14.3%, including 20.4% early onset. Patients with GBA-PD had earlier and more frequent occurrence of several nonmotor symptoms. Patients with severe and complex GBA-PD had the highest burden of symptoms and a higher risk of hallucinations and cognitive impairment. Complex GBA-PD had the lowest ß-glucocerebrosidase activity. CONCLUSIONS: GBA-PD is highly prevalent in Italy. Different types of mutations underlie distinct phenotypic profiles. © 2020 International Parkinson and Movement Disorder Society.

Defining Dysbiosis in Disorders of Movement and Motivation.

The gut microbiota has emerged as a critical player in shaping and modulating brain function and has been shown to influence numerous behaviors, including anxiety and depression-like behaviors, sociability, and cognition. However, the effects of the gut microbiota on specific disorders associated with thalamo-cortico-basal ganglia circuits, ranging from compulsive behavior and addiction to altered sensation and motor output, are only recently being explored. Wholesale depletion and alteration of gut microbial communities in rodent models of disorders, such as Parkinson's disease, autism, and addiction, robustly affect movement and motivated behavior. A new frontier therefore lies in identifying specific microbial alterations that affect these behaviors and understanding the underlying mechanisms of action. Comparing alterations in gut microbiota across multiple basal-ganglia associated disease states allows for identification of common mechanistic pathways that may interact with distinct environmental and genetic risk factors to produce disease-specific outcomes.

Image-based analysis and long-term clinical outcomes of deep brain stimulation for Tourette syndrome: a multisite study.

BACKGROUND: Deep brain stimulation (DBS) can be an effective therapy for tics and comorbidities in select cases of severe, treatment-refractory Tourette syndrome (TS). Clinical responses remain variable across patients, which may be attributed to differences in the location of the neuroanatomical regions being stimulated. We evaluated active contact locations and regions of stimulation across a large cohort of patients with TS in an effort to guide future targeting. METHODS: We collected retrospective clinical data and imaging from 13 international sites on 123 patients. We assessed the effects of DBS over time in 110 patients who were implanted in the centromedial (CM) thalamus (n=51), globus pallidus internus (GPi) (n=47), nucleus accumbens/anterior limb of the internal capsule (n=4) or a combination of targets (n=8). Contact locations (n=70 patients) and volumes of tissue activated (n=63 patients) were coregistered to create probabilistic stimulation atlases. RESULTS: Tics and obsessive-compulsive behaviour (OCB) significantly improved over time (p<0.01), and there were no significant differences across brain targets (p>0.05). The median time was 13 months to reach a 40% improvement in tics, and there were no significant differences across targets (p=0.84), presence of OCB (p=0.09) or age at implantation (p=0.08). Active contacts were generally clustered near the target nuclei, with some variability that may reflect differences in targeting protocols, lead models and contact configurations. There were regions within and surrounding GPi and CM thalamus that improved tics for some patients but were ineffective for others. Regions within, superior or medial to GPi were associated with a greater improvement in OCB than regions inferior to GPi. CONCLUSION: The results collectively indicate that DBS may improve tics and OCB, the effects may develop over several months, and stimulation locations relative to structural anatomy alone may not predict response. This study was the first to visualise and evaluate the regions of stimulation across a large cohort of patients with TS to generate new hypotheses about potential targets for improving tics and comorbidities.

Sociodemographic, Attitudinal, and Behavioral Correlates of Using Nutrition, Weight Loss, and Fitness Websites: An Online Survey.

BACKGROUND: Nutrition, diet, and fitness are among the most searched health topics by internet users. Besides that, health-related internet users are diverse in their motivations and individual characteristics. However, little is known about the individual characteristics associated with the usage of nutrition, weight loss, and fitness websites. OBJECTIVE: The aim of this study was to examine the individual factors associated with the usage of nutrition, weight loss, and fitness websites. METHODS: An invitation to an online survey was published on 65 websites and discussion forums. In total, we employed data from 623 participants (aged 13 to 39 years, mean 24.11 [SD 5.26]). The measures included frequency of usage of nutrition, weight loss and fitness websites, excessive exercise, eating disorder symptomatology, internalization of the beauty ideal, weight status, and perceived online social support. Participants' data were used as predictors in a base linear regression model. RESULTS: The final model had an acceptable fit (χ210 =14.1; P=.17; root mean square error of approximation=0.03; comparative fit index=0.99; Tucker-Lewis index=0.99). Positive associations were found between usage of (1) nutrition websites and being female, higher levels of excessive exercise, and perceived online social support; (2) weight loss websites and excessive exercise, internalization, being female, eating disorder symptomatology, and being overweight or obese; and (3) fitness websites and levels of excessive exercise, internalization, and frequency of internet use. CONCLUSIONS: The results highlighted the importance of individual differences in the usage of health-related websites.

FLUOXETINE THERAPY TO DECREASE STEREOTYPIC BEHAVIOR IN THE ASIATIC BLACK BEAR (URSUS THIBETANUS).

The present study evaluated the effects of fluoxetine on decreasing stereotypic behaviors in Asiatic black bears (ABB). Four captive ABB exhibiting stereotypic behaviors were administered fluoxetine (0.25-1 mg/ kg orally every 24 hr) for 91 days. The animals were monitored twice weekly for 213 days (April to October) using a scan sampling method (preadministration, 30 day; administration, 91 days; postadministration, 92 days). Five blood samples were collected from the jugular vein of each bear for serum chemistry analysis (one during preadministration; two each during administration and postadministration periods). Fluoxetine was safe and effective in decreasing stereotypies, but it may be difficult to decrease long-established stereotypies in ABB using fluoxetine alone. To decrease stereotypies in ABB effectively, it is necessary to identify underlying problems that contribute to stereotypic behavior and apply comprehensive interventions that can include fluoxetine treatment.

Determinants of compulsive buying behavior among young adults: The mediating role of materialism.

This research seeks to determine what makes young adults materialistic. The study examines the mediating role of materialism between the contextual factors and compulsive buying. Data was gathered from 219 Pakistani undergraduate university students. Partial Least Square (PLS) technique was used to analyze the data. The study confirms the intuition that more materialistic young adults are more likely to be involved in compulsive buying than are less materialistic young adults. The results were similar with the previous literature conducted in the western culture, indicating that also applies in a modern Islamic society. The findings of the study reveal that materialism mediated the relationship between certain sociological factors (i.e., group, media Celebrity endorsement, and TV advertisement) and compulsive buying. The study highlights the importance of understanding young adults' materialistic attitudes and consumption decisions and provides key knowledge for researchers, policymakers, and managers of leading brands.