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Fulltext The theoretical model of school refusal: the self-efficacy concept

Maruzairi Husain, Ng, Vi Vien

Malaysian Journal of Paediatrics and Child Health, 2019;25(2):7-13.
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Introduction: School refusal is a common cause of chronically poor school attendance. The basis of school refusal behaviour can be grouped into the symptomatic and functional models, the operant conditioning model and the cognitive model. Objective: This paper is aimed to discuss the various systems and models which explain the school refusal behaviour. Method: An initial search of published literature in English Language was performed on the online databases including Google Scholar, Science Direct, EBSCOhost, and Proquest with the main keywords were School Refusal and Self–efficacy. Further sources were identified after consulting the original author for recommendations, and references within the literature retrieved in the initial search. Results: Out of 57 articles found, 41 were used in this review. Development and maintenance of school refusal involve heterogeneous risk factors and processes. The existing theoretical basis of school refusal behaviour can be grouped into symptomatic models, the operant conditioning model and the cognitive model. Conclusion: School refusal depicts a symptom, heralding the need for early intervention before development of a more pervasive mental health disorder. Where the problem had persisted for months to years, the child or adolescent would commonly present with coexisting anxiety or depressive disorders.

Matched MeSH terms: Conditioning, Operant
Fulltext Divergent Solutions to Visual Problem Solving across Mammalian Species

Mustafar F, Harvey MA, Khani A, Arató J, Rainer G

eNeuro, 2018 07 11;5(4).
PMID: 30073190 DOI: 10.1523/ENEURO.0167-18.2018

Our understanding of the neurobiological underpinnings of learning and behavior relies on the use of invasive techniques, which necessitate the use of animal models. However, when different species learn the same task, to what degree are they actually producing the same behavior and engaging homologous neural circuitry? This question has received virtually no recent attention, even as the most powerful new methodologies for measuring and perturbing the nervous system have become increasingly dependent on the use of murine species. Here, we test humans, rats, monkeys, and an evolutionarily intermediate species, tree shrews, on a three alternative, forced choice, visual contrast discrimination task. As anticipated, learning rate, peak performance, and transfer across contrasts was lower in the rat compared to the other species. More interestingly, rats exhibited two major behavioral peculiarities: while monkeys and tree shrews based their choices largely on visual information, rats tended to base their choices on past reward history. Furthermore, as the task became more difficult, rats largely disengaged from the visual stimulus, reverting to innate spatial predispositions in order to collect rewards near chance probability. Our findings highlight the limitation of muridae as models for translational research, at least in the area of visually based decision making.

Matched MeSH terms: Conditioning, Operant/physiology*
Discriminative stimulus properties of mitragynine (kratom) in rats

Harun N, Hassan Z, Navaratnam V, Mansor SM, Shoaib M

Psychopharmacology (Berl), 2015 Jul;232(13):2227-38.
PMID: 25616583 DOI: 10.1007/s00213-015-3866-5

RATIONALE: Mitragynine (MG) is the primary active alkaloid extracted from the leaves of Mitragyna speciosa or kratom and exhibits pharmacological activities mediated by opioid receptors. The plant has been traditionally used for its opium and psychostimulant-like effects to increase work efficiency or as a substitute in the self-treatment of opiate addiction.
OBJECTIVES: The present study was performed to investigate the discriminative stimulus effects of MG in rats. The pharmacological mechanism of MG action and its derivative, 7-hydroxymitragynine (7-HMG) with a specific focus on opioid receptor involvement was examined in rats trained to discriminate morphine from vehicle. In order to study the dual actions of MG, the effect of cocaine substitution to the MG discriminative stimulus was also performed in MG-trained rats.
METHODS: Male Sprague Dawley rats were trained to discriminate MG from vehicle in a two-lever drug discrimination procedure under a tandem variable-interval (VI 60') fixed-ratio (FR 10) schedule of food reinforcement.
RESULTS: Rats acquired the MG discrimination (15.0 mg/kg, i.p.) which was similar to the acquisition of morphine discrimination (5.0 mg/kg, i.p.) in another group of rats. MG substituted fully to the morphine discriminative stimulus in a dose-dependent manner, suggesting pharmacological similarities between the two drugs. The administration of 7-HMG derivative in 3.0 mg/kg (i.p.) dose engendered full generalisation to the morphine discriminative stimulus. In addition, the MG stimulus also partially generalised to cocaine (10.0 mg/kg, i.p.) stimulus.
CONCLUSION: The present study demonstrates that the discriminative stimulus effect of MG possesses both opioid- and psychostimulant-like subjective effects.

Matched MeSH terms: Conditioning, Operant/drug effects*; Conditioning, Operant/physiology
Assessing physiological dependence and withdrawal potential of mitragynine using schedule-controlled behaviour in rats

Harun N, Johari IS, Mansor SM, Shoaib M

Psychopharmacology (Berl), 2020 Mar;237(3):855-867.
PMID: 31832720 DOI: 10.1007/s00213-019-05418-6

RATIONALE: Kratom is proposed to exhibit therapeutic potential as an opium substitute, but little is known about its dependence-producing profile, particularly of its main psychoactive compound, mitragynine (MG).
OBJECTIVES: This study examined the dependence-producing effects of MG using operant-scheduled behaviour in rats and investigated the potential therapeutic effect of MG by comparing effects to buprenorphine in morphine-dependent rats using the same schedule-controlled behavioural task.
METHODS: The effects of acutely administered MG and morphine were determined in rats trained to respond under fixed-ratio (FR) 10 schedule of food reinforcement. Next, the rats were administered MG and morphine twice daily for 14 consecutive days to determine if physiological dependence would develop by examining cessation of drug treatment and following antagonist-precipitated withdrawal. The study then examined the effects of MG substitution to suppress naloxone-precipitated morphine withdrawal effects on scheduled responding.
RESULTS: Acute doses of MG did not produce dose-related decreases on FR schedules of responding compared to morphine. Unlike morphine, MG-treated rats showed no suppression of response rates following cessation of MG treatment. However, withdrawal effects were evident for MG after precipitation by either naloxone or SR141716A (rimonabant), similar to morphine-treated rats. MG in higher doses (10 and 30 mg/kg) attenuated the naloxone-precipitated morphine withdrawal effects while smaller doses of buprenorphine (0.3 and 1.0 mg/kg) were necessary to alleviate these effects.
CONCLUSION: The findings suggest that MG does not induce physiological dependence but can alleviate the physical symptoms associated with morphine withdrawal which represent the desired characteristics of novel pharmacotherapeutic interventions for managing opioid use disorder (OUD).

Matched MeSH terms: Conditioning, Operant/drug effects; Conditioning, Operant/physiology
Methanolic extract of Mitragyna speciosa Korth leaf inhibits ethanol seeking behaviour in mice: involvement of antidopaminergic mechanism

Vijeepallam K, Pandy V, Murugan DD, Naidu M

Metab Brain Dis, 2019 12;34(6):1713-1722.
PMID: 31396844 DOI: 10.1007/s11011-019-00477-2

In the current study, the effect of methanolic extract of Mitragyna speciosa leaf (MMS) against the rewarding and reinforcing properties of ethanol using a mouse model of conditioned place preference (CPP) and runway model of drug self-administration was studied. Subsequently, the effect of MMS on dopamine level in the nucleus accumbens (NAc) of the mouse brain was further investigated. From the data obtained, MMS (50 and 75 mg/kg, p.o.) significantly reversed the ethanol-place preference in mice, which is similar to the effect observed in the reference drugs acamprosate (300 mg/kg, p.o.) and clozapine (1 mg/kg, p.o.) treatment groups in CPP test. Likewise, the escalating doses of ethanol-conditioned mice reduced the runtime to reach goal box, infers the positive reinforcing effects of alcohol. Interestingly, MMS (50, 75 and 100 mg/kg, p.o.) significantly prolonged the runtime in ethanol-conditioned mice. Besides, MMS (50 and 75 mg/kg, p.o.) and reference drugs; acamprosate (300 mg/kg, p.o.) and clozapine (1 mg/kg, p.o.) treated mice significantly decreased the alcohol-induced elevated dopamine level in the NAc region of the brain. Overall, this study provides first evidence that MMS inhibits ethanol seeking behaviour in mice. Based on these findings, we suggest that Mitragyna speciosa may well be utilized for novel drug development to combat alcohol dependence.

Matched MeSH terms: Conditioning, Operant/drug effects
MicroRNA expression signature of methamphetamine use and addiction in the rat nucleus accumbens

Sim MS, Soga T, Pandy V, Wu YS, Parhar IS, Mohamed Z

Metab Brain Dis, 2017 Dec;32(6):1767-1783.
PMID: 28681200 DOI: 10.1007/s11011-017-0061-x

Methamphetamine (METH) is a highly addictive psycho-stimulant that induces behavioral changes due to high level of METH-induced dopamine in the brain. Nucleus accumbens (NAc) plays an important role in these changes, especially in drug addiction. However, little is known about the underlying molecular mechanisms of METH-induced addiction. The objective of this study was to establish a behavioral model of METH use and addiction using escalating doses of METH over 15 days and to determine the global miRNA expression profiling in NAc of METH-addicted rats. In the behavioral study, the experimental rats were divided into 3 groups of 9 each: a control group, a single dose METH (5 mg/kg) treatment group and a continuous 15 alternate days METH (0.25, 0.5, 1, 2, 3, 4, 5 mg/kg) treatment group. Following that, six rats in each group were randomly selected for global miRNA profiling. Addiction behavior in rats was established using Conditioned Place Preference task. The analysis of the miRNA profiling in the NAc was performed using Affymetric microarray GeneChip® System. The findings indicated that a continuous 15 alternate days METH treatment rats showed a preference for the drug-paired compartment of the CPP. However, a one-time acute treatment with 5 mg/kg METH did not show any significant difference in preference when compared with controls. Differential profiling of miRNAs indicated that 166 miRNAs were up-regulated and 4 down-regulated in the chronic METH-treatment group when compared to controls. In comparing the chronic treatment group with the acute treatment group, 52 miRNAs were shown to be up-regulated and 7 were down-regulated. MiRNAs including miR-496-3p, miR-194-5p, miR-200b-3p and miR-181a-5p, were found to be significantly associated with METH addiction. Canonical pathway analysis revealed that a high number of METH addiction-related miRNAs play important roles in the MAPK, CREB, G-Protein Couple Receptor and GnRH Signaling pathways. Our results suggest that dynamic changes occur in the expression of miRNAs following METH exposure and addiction.

Matched MeSH terms: Conditioning, Operant/drug effects