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Amphetamine Selectively Enhances Avoidance Responding To A Less Salient Stimulus In Rats, Ming Li, Wei He, Rebecca Munro May 2012

Amphetamine Selectively Enhances Avoidance Responding To A Less Salient Stimulus In Rats, Ming Li, Wei He, Rebecca Munro

Ming Li

This preclinical study examined the psychological processes affected by amphetamine that contribute to human psychosis. Using a novel avoidance conditioning paradigm involving two conditioned stimuli (CS) with varied salience, we found that acute amphetamine (1.5 mg/ kg, i.p.) selectively enhanced avoidance responding to a less salient stimulus, but not to a salient one. These findings suggest that elevated dopaminergic activity selectively enhances the attributions of motivational salience to a less salient stimulus, a process that may bear relevance to the development of human delusional thoughts.


Nicotine As A Signal For The Presence Or Absence Of Sucrose Reward: Pavlovian Drug Appetitive Conditioning Preparation In Rats, Joyce Besheer, Matthew I. Palmatier, Dawn M. Metschke, Rick A. Bevins May 2012

Nicotine As A Signal For The Presence Or Absence Of Sucrose Reward: Pavlovian Drug Appetitive Conditioning Preparation In Rats, Joyce Besheer, Matthew I. Palmatier, Dawn M. Metschke, Rick A. Bevins

Rick A. Bevins

Rationale: In Pavlovian conditioning research, nicotine is typically conceptualized as the unconditioned stimulus (US) that becomes associated with an exteroceptive conditioned stimulus (CS). This research has not explored the possibility that nicotine can also function as a CS. Objectives: The present research examined whether nicotine served as a CS for the presence (CS+) or absence (CS–) of sucrose and started defining its specificity. Methods and results: Rats trained in the CS+ condition had nicotine (0.4 mg/kg, base) paired intermittently with brief access to sucrose. Intermixed were saline sessions without sucrose. Nicotine acquired the ability to evoke goal tracking. This conditioned …


Characterization Of Nicotine’S Ability To Serve As A Negative Feature In A Pavlovian Appetitive Conditioning Task In Rats, Rick A. Bevins, Jamie L. Wilkinson, Matthew I. Palmatier, Hannah L. Siebert, Steven M. Wiltgen May 2012

Characterization Of Nicotine’S Ability To Serve As A Negative Feature In A Pavlovian Appetitive Conditioning Task In Rats, Rick A. Bevins, Jamie L. Wilkinson, Matthew I. Palmatier, Hannah L. Siebert, Steven M. Wiltgen

Rick A. Bevins

Rationale Pavlovian feature negative discriminations have been widely used to understand inhibitory conditioning processes using exteroceptive stimuli. Comparatively little is known about inhibitory conditioning processes using a drug state as a negative feature. A negative feature signals that presentation of a conditional stimulus (CS) will not be paired with an unconditioned stimulus. Objectives: The present research examined whether nicotine served as a negative feature and started characterizing its properties. Methods and results: In acquisition, rats received intermixed saline and nicotine (0.4 mg/kg, base) sessions. On saline sessions, a 15-s light CS was paired with 4-s access to sucrose; the CS …


Individual Differences In Behavioral Responses To Novelty And Amphetamine Self-Administration In Male And Female Rats, J. E. Klebaur, Rick A. Bevins, T. M. Segar, M. T. Bardo May 2012

Individual Differences In Behavioral Responses To Novelty And Amphetamine Self-Administration In Male And Female Rats, J. E. Klebaur, Rick A. Bevins, T. M. Segar, M. T. Bardo

Rick A. Bevins

Previous work has shown that individual differences in locomotor activity in an inescapable novel environment can predict acquisition of amphetamine self-administration. The current study examined whether individual differences in approach to novelty in a free choice test could also predict amphetamine self-administration. Further, the current study examined whether individual differences in either free choice or inescapable novelty tests could predict responding for a nondrug reinforcer (sucrose) in the presence and absence of amphetamine. Male and female rats were first tested for their response to free choice novelty (playground maze and novelty-induced place preference tests) and inescapable novelty. They were then …


Individual Differences In Response To Novelty, Amphetamine-Induced Activity And Drug Discrimination In Rats, Rick A. Bevins, J. E. Klebaur, M. T. Bardo May 2012

Individual Differences In Response To Novelty, Amphetamine-Induced Activity And Drug Discrimination In Rats, Rick A. Bevins, J. E. Klebaur, M. T. Bardo

Rick A. Bevins

Rats mere pre-tested in several individual difference screens - novelty-induced activity, novelty-induced place preference, novel-object interaction, and amphetamine-induced activity. Rats that were more sensitive to the locomotor effects of amphetamine were more active in an inescapable novel environment and displayed a greater preference for a novel environment. All animals were then trained to discriminate amphetamine (1 mg/kg) from saline in a two-bar discrimination procedure using food-maintained responding. After acquisition of the discrimination (mean =37 trials), two amphetamine generalization tests (0.0625,0.125,0.25,0.5, 1.0 and 2.0 mg/kg) were conducted. In the second generalization test, rats that were more sensitive to the activating effect …


Locomotion And Conditioned Place Preference Produced By Acute Intravenous Amphetamine: Role Of Dopamine Receptors And Individual Differences In Amphetamine Self-Administration, M. T. Bardo, J. M. Valone, Rick A. Bevins May 2012

Locomotion And Conditioned Place Preference Produced By Acute Intravenous Amphetamine: Role Of Dopamine Receptors And Individual Differences In Amphetamine Self-Administration, M. T. Bardo, J. M. Valone, Rick A. Bevins

Rick A. Bevins

Although previous studies have shown that dopamine (DA) antagonists block amphetamine reward, these studies have utilized animal models that involve repeated exposures to amphetamine. The present investigation examined the effect of DA antagonists on single-trial conditioned place preference (CPP) produced by acute intravenous (IV) amphetamine in rats. In the first experiment, rats were prepared with a jugular catheter and then received an acute IV injection of amphetamine (0.1–3 mg/kg) paired with one compartment of a CPP apparatus. Relative to sham controls (no IV catheter), amphetamine produced a dose-dependent increase in locomotor activity and CPP. Two further experiments demonstrated that both …


Differential Effects Of Acute Amphetamine And Phencyclidine Treatment And Withdrawal From Repeated Amphetamine Or Phencyclidine Treatment On Social Interaction And Social Memory In Rats, Ming Li, Wei He, Rebecca Munro Jan 2012

Differential Effects Of Acute Amphetamine And Phencyclidine Treatment And Withdrawal From Repeated Amphetamine Or Phencyclidine Treatment On Social Interaction And Social Memory In Rats, Ming Li, Wei He, Rebecca Munro

Department of Psychology: Faculty Publications

Although animal models based on amphetamine (AMPH) or phencyclidine (PCP) treatment have been used extensively to study the neurobiological and behavioral characteristics of schizophrenia, there are conflicting reports regarding their validity in modeling the negative symptoms and cognitive deficits of schizophrenia. The present study examined how acute AMPH or PCP treatment (Experiment 1) and withdrawal from repeated AMPH treatment (Experiment 2) or PCP treatment (Experiment 3) affects social behavior and social recognition memory in male Sprague-Dawley rats. Each subject was tested on two consecutive days. On the first day, the rats were tested four times (5 min/each) at 10-min intervals …