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https://www.readbyqxmd.com/read/28101925/-watch-out-effects-of-instructed-threat-and-avoidance-on-human-free-operant-approach-avoidance-behavior
#1
Michael W Schlund, Kay Treacher, Oli Preston, Sandy K Magee, David M Richman, Adam T Brewer, Gemma Cameron, Simon Dymond
Approach-avoidance paradigms create a competition between appetitive and aversive contingencies and are widely used in nonhuman research on anxiety. Here, we examined how instructions about threat and avoidance impact control by competing contingencies over human approach-avoidance behavior. Additionally, Experiment 1 examined the effects of threat magnitude (money loss amount) and avoidance cost (fixed ratio requirements), whereas Experiment 2 examined the effects of threat information (available, unavailable and inaccurate) on approach-avoidance...
January 2017: Journal of the Experimental Analysis of Behavior
https://www.readbyqxmd.com/read/28101921/effects-of-shifts-in-food-reinforcement-context-on-rats-consumption-of-concurrently-available-water-or-sucrose-solution
#2
Chad M Galuska, Leslie E Sawyer
The purpose of this study was to investigate the effects of signaled transitions from relatively rich to lean conditions of food reinforcement on drinking concurrently available water or sucrose-sweetened water in rats. Past research demonstrated that these negative incentive shifts produce behavioral disruption in the form of extended pausing on fixed-ratio schedules. Four male Long-Evans rats operated on a two-component multiple fixed-ratio fixed-ratio schedule. In one manipulation, the ratio was held constant and the components arranged either a large six-pellet reinforcer (rich) or small one-pellet reinforcer (lean)...
January 2017: Journal of the Experimental Analysis of Behavior
https://www.readbyqxmd.com/read/28078744/escape-from-rich-to-lean-transitions-stimulus-change-and-timeout
#3
Billie J Retzlaff, Elizabeth T P Parthum, Raymond C Pitts, Christine E Hughes
Extended pausing during discriminable transitions from rich-to-lean conditions can be viewed as escape (i.e., rich-to-lean transitions function aversively). In the current experiments, pigeons' key pecking was maintained by a multiple fixed-ratio fixed-ratio schedule of rich or lean reinforcers. Pigeons then were provided with another, explicit, mechanism of escape by changing the stimulus from the transition-specific stimulus used in the multiple schedule to a mixed-schedule stimulus (Experiment 1) or by producing a period of timeout in which the stimulus was turned off and the schedule was suspended (Experiment 2)...
January 2017: Journal of the Experimental Analysis of Behavior
https://www.readbyqxmd.com/read/28078680/children-s-preference-for-mixed-versus-fixed-ratio-schedules-of-reinforcement-a-translational-study-of-risky-choice
#4
Michael P Mullane, Brian K Martens, Emily L Baxter, Danica Ver Steeg
Laboratory research has shown that when subjects are given a choice between fixed-ratio and bi-valued mixed-ratio schedules of reinforcement, preference typically emerges for the mixed-ratio schedule even with a larger ratio requirement. The current study sought to replicate and extend these findings to children's math problem completion. Using an ABCBC reversal design, four fourth-grade students were given the choice of completing addition problems reinforced on either a fixed-ratio 5 schedule or one of three mixed-ratio schedules; an equivalent mixed-ratio (1, 9) schedule, a mixed-ratio (1, 11) schedule with a 20% larger ratio requirement, and an equally lean mixed-ratio (5, 7) schedule without the small fixed-ratio 1 component...
January 2017: Journal of the Experimental Analysis of Behavior
https://www.readbyqxmd.com/read/28077308/cookie-or-fruit-relative-reinforcing-value-of-snack-foods-among-preschoolers-with-overweight-obesity-compared-to-healthy-weight
#5
Mary Beth McCullough, Hayley Guilkey, Lori Stark
The reinforcing value of food is an important determinant of food intake. Research has yet to examine the relative reinforcing value (RRV) of snack foods in young children with overweight and obesity (OW/OB). The current study compared the RRV of high-energy dense foods (cookies) to low-energy dense foods (fruits) between preschoolers with OW/OB and healthy weight (HW). RRV of cookies and fruits in preschoolers with OW/OB (n = 30; Mage = 4.4 ± 0.84; 60% male) and HW (n = 30; Mage = 4.5 ± 0.85; 70% male) was assessed with a developmentally-tailored computer program which used a progressive fixed ratio reward schedule...
January 8, 2017: Appetite
https://www.readbyqxmd.com/read/28065844/effects-of-the-chronic-restraint-stress-induced-depression-on-reward-related-learning-in-rats
#6
Pan Xu, Kezhu Wang, Cong Lu, Liming Dong, Yixi Chen, Qiong Wang, Zhe Shi, Yanyan Yang, Shanguang Chen, Xinmin Liu
Chronic mild or unpredictability stress produces a persistent depressive-like state. The main symptoms of depression include weight loss, despair, anhedonia, diminished motivation and mild cognition impairment, which could influence the ability of reward-related learning. In the present study, we aimed to evaluate the effects of chronic restraint stress on the performance of reward-related learning of rats. We used the exposure of repeated restraint stress (6h/day, for 28days) to induce depression-like behavior in rats...
January 5, 2017: Behavioural Brain Research
https://www.readbyqxmd.com/read/28059083/behavioral-determinants-of-cannabinoid-self-administration-in-old-world-monkeys
#7
William S John, Thomas J Martin, Michael A Nader
Reinforcing effects of Δ(9)-tetrahydrocannabinol (THC), the primary active ingredient in marijuana, as assessed with self-administration (SA), has only been established in New World primates (squirrel monkeys). The objective of this study was to investigate some experimental factors that may enhance intravenous SA of THC and the cannabinoid receptor (CBR) agonist CP 55 940 in Old World monkeys (rhesus and cynomolgus), a species that has been used extensively in biomedical research. In one experiment, male rhesus monkeys (N=9) were trained to respond under a fixed-ratio 10 schedule of food presentation...
January 6, 2017: Neuropsychopharmacology: Official Publication of the American College of Neuropsychopharmacology
https://www.readbyqxmd.com/read/28033493/the-time-dependent-synergism-of-the-six-component-mixtures-of-substituted-phenols-pesticides-and-ionic-liquids-to-caenorhabditis-elegans
#8
Li Feng, Shu-Shen Liu, Kai Li, Han-Xiao Tang, Hai-Ling Liu
Traditional environmental risk assessment rarely focused on exposures to multi-component mixtures which may cause toxicological interactions and usually ignored that toxicity is a process in time, which may underestimate the environment risk of mixtures. In this paper, six chemicals belonging to three categories, two substituted phenols, two pesticides and two Ionic liquids, were picked to construct a six-component mixture system. To systematically examine the effects of various concentration compositions, the uniform design ray method was employed to design nine mixture rays with nine mixture ratios and for every mixture ray 12 concentration levels were specified by the fixed ratio ray design...
December 19, 2016: Journal of Hazardous Materials
https://www.readbyqxmd.com/read/28007642/suppressing-effect-of-saikosaponin-a-an-active-ingredient-of-bupleurum-falcatum-on-chocolate-self-administration-and-reinstatement-of-chocolate-seeking-in-rats
#9
Irene Lorrai, Paola Maccioni, Mauro A M Carai, Alessandro Capra, M Paola Castelli, Antonella Riva, Paolo Morazzoni, Gian Luigi Gessa, Giancarlo Colombo
Recent lines of experimental evidence have indicated that saikosaponin A (SSA) - a bioactive ingredient of the medicinal plant, Bupleurum falcatum L. - suppressed alcohol, morphine, and cocaine self-administration in rats. The present paper was designed to assess whether the protective properties of SSA on addiction-related behaviors generalize to a hyperpalatable food such as a chocolate-flavored beverage (CFB). To this end, rats were initially trained to lever-respond for CFB [5% (w/v) Nesquik(®) powder in water] under fixed ratio (FR) 10 (FR10) schedule of reinforcement...
December 19, 2016: Neuroscience Letters
https://www.readbyqxmd.com/read/28000221/substitution-effects-in-a-generalized-token-economy-with-pigeons
#10
Leonardo F Andrade, Timothy D Hackenberg
Pigeons made repeated choices between earning and exchanging reinforcer-specific tokens (green tokens exchangeable for food, red tokens exchangeable for water) and reinforcer-general tokens (white tokens exchangeable for food or water) in a closed token economy. Food and green food tokens could be earned on one panel; water and red water tokens could be earned on a second panel; white generalized tokens could be earned on either panel. Responses on one key produced tokens according to a fixed-ratio schedule, whereas responses on a second key produced exchange periods, during which all previously earned tokens could be exchanged for the appropriate commodity...
January 2017: Journal of the Experimental Analysis of Behavior
https://www.readbyqxmd.com/read/27986974/effects-of-a-serotonin-2c-agonist-and-a-2a-antagonist-on-actigraphy-based-sleep-parameters-disrupted-by-methamphetamine-self-administration-in-rhesus-monkeys
#11
Maylen Perez Diaz, Monica L Andersen, Kenner C Rice, Leonard L Howell
Sleep disorders and substance abuse are highly comorbid and we have previously shown that methamphetamine self-administration significantly disrupts activity-based sleep parameters in rhesus monkeys. To the best of our knowledge, no study has evaluated the effectiveness of any pharmacological intervention to attenuate the effects of methamphetamine on nighttime activity under well-controlled conditions in laboratory animals. Thus, we examined the effects of a 5-HT2C receptor agonist, WAY163909, and a 5-HT2A receptor antagonist, M100907, given alone and in combination, on actigraphy-based sleep parameters disrupted by methamphetamine self-administration in non-human primates...
January 18, 2017: Neuropsychopharmacology: Official Publication of the American College of Neuropsychopharmacology
https://www.readbyqxmd.com/read/27940077/the-discriminative-stimulus-effects-of-i-v-nicotine-in-rhesus-monkeys-pharmacokinetics-and-apparent-pa2-analysis-with-dihydro-%C3%AE-erythroidine
#12
Megan J Moerke, Andy Z X Zhu, Rachel F Tyndale, Martin A Javors, Lance R McMahon
Quantitative analysis of antagonism is infrequently used to identify nAChRs mediating behavioral effects. Here, nicotine (0.032 mg/kg i.v.) was established as a discriminative stimulus in rhesus monkeys responding under a fixed ratio 5 schedule; pharmacokinetics and underlying nAChR mechanism(s) were examined. When measured up to 4 h in venous blood, the training dose resulted in the following mean pharmacokinetic parameters: nicotine Cmax = 71.7 ng/ml, t1/2 = 116 min, and clearance = 6.25 ml/min/kg; cotinine Cmax = 191 ng/ml; and 3OH-cotinine Cmax = 63 ng/ml...
December 8, 2016: Neuropharmacology
https://www.readbyqxmd.com/read/27935269/from-adolescent-to-elder-rats-motivation-for-palatable-food-and-cannabinoids-receptors
#13
Octavio Amancio-Belmont, Antonio Romano-López, Alejandra Evelin Ruiz-Contreras, Mónica Méndez-Díaz, Oscar Prospéro-García
To analyze motivation, food self-administration and decision-making was evaluated in adolescent, adult and aged rats. Subjects were trained to press a lever (fixed ratio, FR1 and FR5) in an operant chamber, to obtain chocolate flavor pellets. We assessed the progressive ratio (PR), extinction and reinstatement of the behavior. To estimate decision-making for food, rats were trained in the conditioned place preference (CPP) paradigm: a) associating one compartment with lab chow (LCh) one day and the other compartment with rice krisspies (RK), the next day...
December 9, 2016: Developmental Neurobiology
https://www.readbyqxmd.com/read/27929349/effects-of-paclitaxel-on-mechanical-sensitivity-and-morphine-reward-in-male-and-female-c57bl6-mice
#14
Harshini Neelakantan, Sara Jane Ward, Ellen Ann Walker
This study evaluated the hypothesis that a paclitaxel treatment regimen sufficient to produce mechanical allodynia would alter sensitivities of male and female mice to the conditioned rewarding and reinforcing effects of morphine. Saline or paclitaxel were administered on Days 1, 3, 5, and 7 in male and female C57Bl/6 mice to induce morphine-reversible mechanical allodynia as measured by the Von Frey filament test. Paclitaxel treatment did not change sensitivity to morphine conditioned place preference (CPP) relative to saline treatment in either male or female mice...
December 2016: Experimental and Clinical Psychopharmacology
https://www.readbyqxmd.com/read/27924478/evaluating-synergistic-effects-of-mir-34a-mimics-in-combination-with-other-therapeutic-agents-in-cultured-non-small-cell-lung-cancer-cells
#15
Jane Zhao, Andreas G Bader
Tumor suppressor miRNAs such as miR-34a inhibit tumor growth by simultaneously regulating the expression of multiple important oncogenes across multiple oncogenic pathways and, therefore, provide a strong rationale for developing therapeutic miRNA mimics in combination with other therapeutic cancer agents to augment drug sensitivity. Here, we describe the experimental approach for evaluating miRNA and drug combinations using the "fixed ratio" method in cultured non-small cell lung cancer cells.
2017: Methods in Molecular Biology
https://www.readbyqxmd.com/read/27921428/-promising-molecules-for-treatment-of-hyperglycemia-in-patients-with-type-2-diabetes
#16
Milan Kvapil
New antidiabetic drugs are being developed today that expand the range of pharmacological intervention, in particular for patients with type 2 diabetes (imeglimin, semaglutide, dulaglutide, FGF 21 analogue). At the same time innovations take place that "better" the well-proven molecules, they offer new application forms we have no experience of diabetology (osmotic pump for exenatide, faster acting insulin aspart). New properties are brought by just the change of concentration (insulin glargine in a concentration of 300 U/ml), unexpected positive results are also brought by new fixed-ratio combinations of antidiabetics (fixed-ratio combination of insulin degludec and liraglutide, fixed-ratio combination of insulin glargine and lixisenatide)...
2016: Vnitr̆ní Lékar̆ství
https://www.readbyqxmd.com/read/27896377/self-administration-and-behavioral-economics-of-second-generation-synthetic-cathinones-in-male-rats
#17
S L Huskinson, J E Naylor, E A Townsend, J K Rowlett, B E Blough, K B Freeman
RATIONALE: Synthetic cathinones have become increasingly available as drugs of abuse. Distribution of these drugs is made possible by altering the chemical structures of prohibited cathinones and marketing them under misleading labels. Very little is known about the relative reinforcing effectiveness of new synthetic cathinones relative to known drugs of abuse. OBJECTIVE: We examined self-administration of three second-generation synthetic cathinones: alpha-pyrrolidinopentiophenone (alpha-PVP), 4-methyl-N-ethylcathinone (4-MEC), and 4-methyl-alpha-pyrrolidinopropiophenone (4-MePPP) relative to methamphetamine...
November 28, 2016: Psychopharmacology
https://www.readbyqxmd.com/read/27888373/combined-toxic-effect-of-airborne-heavy-metals-on-human-lung-cell-line-a549
#18
Yeowool Choi, Kihong Park, Injeong Kim, Sang D Kim
Many studies have demonstrated that heavy metals existing as a mixture in the atmospheric environment cause adverse effects on human health and are important key factors of cytotoxicity; however, little investigation has been conducted on a toxicological study of a metal mixture from atmospheric fine particulate matter. The objective of this study was to predict the combined effects of heavy metals in aerosol by using in vitro human cells and obtain a suitable mixture toxicity model. Arsenic, nickel, and lead were selected for mixtures exposed to A549 human lung cancer cells...
November 25, 2016: Environmental Geochemistry and Health
https://www.readbyqxmd.com/read/27886524/effects-of-ethanol-on-cocaine-self-administration-in-monkeys-responding-under-a-second-order-schedule-of-reinforcement
#19
William S John, Michael A Nader
BACKGROUND: Concurrent alcohol use among cocaine abusers is common but the behavioral variables that promote co-abuse are not well understood. The present study examined the effects of intragastric (i.g.) ethanol (EtOH) administration in monkeys responding under a schedule of cocaine reinforcement in which extensive drug seeking was maintained by conditioned stimuli. METHODS: Four adult male cynomolgus monkeys (Macaca fascicularis) were trained to respond under a second-order fixed-interval (FI) 600s (fixed-ratio (FR) 30:S) schedule of cocaine (0...
January 1, 2017: Drug and Alcohol Dependence
https://www.readbyqxmd.com/read/27869181/functional-states-of-rat-cortical-circuits-during-the-unpredictable-availability-of-a-reward-related-cue
#20
Iván Fernández-Lamo, Raudel Sánchez-Campusano, Agnès Gruart, José M Delgado-García M
Proper performance of acquired abilities can be disturbed by the unexpected occurrence of external changes. Rats trained with an operant conditioning task (to press a lever in order to obtain a food pellet) using a fixed-ratio (1:1) schedule were subsequently placed in a Skinner box in which the lever could be removed randomly. Field postsynaptic potentials (fPSPs) were chronically evoked in perforant pathway-hippocampal CA1 (PP-CA1), CA1-subiculum (CA1-SUB), CA1-medial prefrontal cortex (CA1-mPFC), mPFC-nucleus accumbens (mPFC-NAc), and mPFC-basolateral amygdala (mPFC-BLA) synapses during lever IN and lever OUT situations...
November 21, 2016: Scientific Reports
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