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Articles 1 - 27 of 27
Full-Text Articles in Psychology
Local Field Potentials In The Male Rat Nucleus Accumbens During Effort-Based Behavior, Celine Aliko, John Salamone, Alev Ecevitoglu
Local Field Potentials In The Male Rat Nucleus Accumbens During Effort-Based Behavior, Celine Aliko, John Salamone, Alev Ecevitoglu
Honors Scholar Theses
Major depression is a devastating disorder that consists of multiple symptoms such as low mood and motivational dysfunction. It has been shown that motivational dysfunction can be studied in animal models by using effort-based choice paradigms, which vary in their response requirements. It has been reported that dopamine depletion in the nucleus accumbens decreases ratio-scheduled lever-pressing in a manner related to the size of the ratio requirement. One dopamine depleting agent is tetrabenazine (TBZ), which has been shown to decrease lever-pressing and induce low-effort bias. The current study aims to investigate behavioral and electrophysiological changes that occur with animals performing …
Variation In Sign-Tracking And Goal-Tracking Behaviors In A Genetically Diverse Inbred Panel Of Mice, Emily A. Schoenblum
Variation In Sign-Tracking And Goal-Tracking Behaviors In A Genetically Diverse Inbred Panel Of Mice, Emily A. Schoenblum
Undergraduate Honors Theses
No abstract provided.
Assessment Of The Triple Reuptake Inhibitor Diclofensine: Effort-Based Decision-Making In A Rodent Model Of Motivational Dysfunction, Sofia Papanikolaou
Assessment Of The Triple Reuptake Inhibitor Diclofensine: Effort-Based Decision-Making In A Rodent Model Of Motivational Dysfunction, Sofia Papanikolaou
Holster Scholar Projects
Serotonin-selective reuptake inhibitors (SSRIs) are the most commonly prescribed antidepressant medications. Despite their popularity, they remain relatively ineffective at treating effort-related motivational symptoms of depression such as fatigue and anergia. Increasing research on triple reuptake inhibitors (TRIs) that target three neurotransmitters—dopamine, serotonin, and norepinephrine—has suggested that TRIs could have efficacy in targeting motivational dysfunction due to their dopaminergic effects. Previous research has shown that the dopamine depleting agent tetrabenazine can reliably induce motivational deficits in rats, as evidenced by a shift towards low-effort behavior in effort-based choice tasks, and provide a validated approach to creating a model of motivational dysfunction. …
Contributions Of Reward Identity And Time Prediction Errors To Pavlovian Learning, Daniel B. Siegel
Contributions Of Reward Identity And Time Prediction Errors To Pavlovian Learning, Daniel B. Siegel
Dissertations, Theses, and Capstone Projects
Some models of associative learning attempt to explain effects such as blocking and unblocking as reflecting a prediction error (PE): Associative strength, and thereby learning, are said to be greater when the unconditioned stimulus (US) received following a cue deviates from one’s expectations. Some models of PE-motivated behavior and PE-relevant brain activity represent the US as a single quantitative variable for outcome value, and that learning therefore only occurs when outcome value differs from expectations. There is growing evidence to suggest that changes in other dimensions of reward, such as identity and timing, also contribute to learning. In Experiment 1, …
The Development And Evaluation Of Novel Da Transport Inhibitors And Their Effects On Effort-Related Motivation: A Review, Mukund Desibhatla
The Development And Evaluation Of Novel Da Transport Inhibitors And Their Effects On Effort-Related Motivation: A Review, Mukund Desibhatla
Honors Scholar Theses
Depression is a debilitating disorder that can cause motivational deficits such as psychomotor retardation, anergia, apathy, and fatigue. Recent research indicates that these motivational deficits, and potential pathways of therapeutic intervention, can be studied in animal models involving rats and mice. Treatments with the VMAT-2 inhibitor tetrabenazine (TBZ) and cytokine interleukin-1ß (IL-1ß) can create a low-effort bias and impair effort-related motivation (Nunes et al. 2013, 2014). A number of high-affinity DA transport inhibitors such as d-amphetamine, methylphenidate, and cocaine can restore extracellular DA, albeit with the cost of undesirable effects such as high abuse liability. These observations have led researchers …
Behavioral, Endocrine, And Neural Responses To Stress In Postpartum And Nulliparous Rats : Potential Mechanisms Of Postpartum Stress Resilience, Joanna Medina
Legacy Theses & Dissertations (2009 - 2024)
Major depressive disorder is one of the most pervasive psychiatric illnesses in the United States. Women are at greater risk for developing depression, particularly during their childbearing years. Approximately 17% of new mothers develop postpartum depression within 4 weeks after parturition. The risk for postpartum depression is even greater in women who do not breastfeed or stop breastfeeding early. Major depressive disorder and postpartum depression share the same symptomology and common etiological bases. Dysregulated stress responses, dopamine activity, and neuroinflammation are recognized mechanisms for depression. The transition to motherhood encompasses physiological and behavioral adaptations in the brain essential for ensuring …
The Effects Of The Atypical Dopamine Uptake Inhibitor Ce-158 On Extracellular Dopamine In The Nucleus Accumbens, Julia Neri
Honors Scholar Theses
Major Depressive Disorder (MDD) is characterized by symptoms such as cognitive dysfunctions, inflammatory changes, and motivational symptoms such as amotivation, fatigue, and anergia. While depressed people are commonly treated by traditional antidepressants such as serotonin reuptake inhibitors (SSRIs), previous studies have reported that SSRI medications do not treat fatigue and anergia symptoms well, and in some cases, can even worsen those symptoms. Subjects treated with dopamine (DA) uptake inhibitors, on the other hand, have been less likely to report symptoms of anergia and fatigue compared to those treated with SSRIs. Common DA uptake inhibitors such as methylphenidate and amphetamines, however, …
The Role Of Dopamine In Decision Making Processes In Drosophila Melanogaster, Michelle C. Bowers
The Role Of Dopamine In Decision Making Processes In Drosophila Melanogaster, Michelle C. Bowers
Undergraduate Honors Theses
Understanding the neural processes that mediate decision making is a relatively new field of investigation in the scientific community. With the ultimate goal of understanding how humans decide between one path and another, simpler models such as Drosophila Melanogaster, the common fruit fly, are often utilized as a way of determining the neural circuits involved in these decision-making processes. One of the most important decisions flies make is the decision of where to lay their eggs (oviposit). Choosing the proper substrate upon which to lay eggs is a crucial decision that can ultimately impact their fecundity. This paper investigates the …
Structure And Function Of Dopamine In The Inner Ear And Auditory Efferent System Of A Vocal Fish, Jonathan T. Perelmuter
Structure And Function Of Dopamine In The Inner Ear And Auditory Efferent System Of A Vocal Fish, Jonathan T. Perelmuter
Dissertations, Theses, and Capstone Projects
The neuromodulator dopamine is considered essential for coordinating the internal motivational state of an organism with appropriate behavioral responses to stimuli in the external environment. This could be accomplished by modifying the function of neural circuits involved in sensory processing such that they are “tuned in” and optimally sensitive to important stimuli during critical time windows. While dopamine modulation of auditory processing has been studied in the central nervous system, neuromodulation can also occur outside the brain, in the inner ear. The majority of investigations of dopamine in the ear are conducted using rodents and focus on its role in …
Murine Genetic Variance In Sugar And Fat-Conditioned Flavor Preferences: Roles Of Dopamine, Opioid And Nmda Receptors And Nutritive Sensing, Tamar T. Kraft
Murine Genetic Variance In Sugar And Fat-Conditioned Flavor Preferences: Roles Of Dopamine, Opioid And Nmda Receptors And Nutritive Sensing, Tamar T. Kraft
Dissertations, Theses, and Capstone Projects
As obesity and diabetes have emerged as a severe public health crisis, understanding the mechanisms underlying the consumption of sugars and fats has become a topic of vigorous study. From a biological standpoint, genetic dispositions, neurochemical and hormonal influences, and predetermined orosensory and postingestive signals that modulate the hunger and satiety process may govern physiological aspects of the obesity puzzle. In addition to an innate appetite and attraction for simple carbohydrates and fats, learning plays an important role in modulating preferences for sugar- and fat-rich foods in rodents, including inbred mouse strains. Marked genetic variance has been observed among murine …
Basal Ganglia Involvement In The Playfulness Of Juvenile Rats, Stephen M. Siviy
Basal Ganglia Involvement In The Playfulness Of Juvenile Rats, Stephen M. Siviy
Psychology Faculty Publications
Play is an important part of normal childhood development and can be readily studied in the laboratory rat in the form of rough‐and‐tumble play. Given the robust nature of rough‐and‐tumble play, it has often been assumed that the basal ganglia would have a prominent role in modulating this behavior. Recent work using c‐fos expression as a metabolic marker for neural activity combined with temporary inactivation of relevant corticostriatal regions and pharmacological manipulations of opioid, cannabinoid, and dopamine systems has led to a better understanding of how basal ganglia circuitry may be involved in modulating social play in the juvenile rat. …
Synchronicity: The Role Of Midbrain Dopamine In Whole-Brain Coordination, Jeff A. Beeler, Jakob Kiskye Dreyer
Synchronicity: The Role Of Midbrain Dopamine In Whole-Brain Coordination, Jeff A. Beeler, Jakob Kiskye Dreyer
Publications and Research
Midbrain dopamine seems to play an outsized role in motivated behavior and learning. Widely associated with mediating reward-related behavior, decision making, and learning, dopamine continues to generate controversies in the field. While many studies and theories focus on what dopamine cells encode, the question of how the midbrain derives the information it encodes is poorly understood and comparatively less addressed. Recent anatomical studies suggest greater diversity and complexity of afferent inputs than previously appreciated, requiring rethinking of prior models. Here, we elaborate a hypothesis that construes midbrain dopamine as implementing a Bayesian selector in which individual dopamine cells sample afferent …
Examining The Associative Learning And Accumbal Dopaminergic Mechanisms Of Caffeine Reinforcement, Curtis Bradley
Examining The Associative Learning And Accumbal Dopaminergic Mechanisms Of Caffeine Reinforcement, Curtis Bradley
Electronic Theses and Dissertations
Caffeine is the most consumed psychoactive substance in the world, and most caffeine consumption in coffee and energy drinks is intended to produce a psychoactive effect. However, caffeine is not a primary reinforcer in preclinical paradigms – non-human species do not reliably take the drug to produce a psychoactive effect. However, caffeine is a ‘reinforcement enhancer’ in preclinical models; the effects of caffeine increase the motivation to obtain other non-drug reinforcers. The overall goal of this project was to determine if these reinforcement enhancing effects of caffeine could promote caffeine self-administration and to subsequently investigate the behavioral and neurochemical underpinnings …
Effort-Related Motivational Dysfunctions: Behavioral And Neurochemical Studies Of The Wistar-Kyoto Rat Model Of Depression, Brendan Abbott
Effort-Related Motivational Dysfunctions: Behavioral And Neurochemical Studies Of The Wistar-Kyoto Rat Model Of Depression, Brendan Abbott
Masters Theses
Depression and related disorders are characterized by motivational dysfunctions, including deficits in behavioral activation and exertion of effort. Animal models of relevance to depression represent a critical starting point in elucidating the neurobiological mechanisms underlying motivational dysfunctions. The present study explored the use of the Wistar-Kyoto (WKY) animal model of depression to examine effort-related functions as measured by voluntary wheel running and performance on a mixed fixed ratio 5/progressive ratio (FR5/PR) operant task. Given the known link between activational aspects of motivation and the mesocorticolimbic dopamine (DA) system, the behavioral effects of d-amphetamine (0.5 and 1.0 mg/kg, IP), a psychostimulant …
Possible Breakdown Of Dopamine Receptor Synergism In A Mouse Model Of Huntington's Disease, Samantha F. Kennedy
Possible Breakdown Of Dopamine Receptor Synergism In A Mouse Model Of Huntington's Disease, Samantha F. Kennedy
University of New Orleans Theses and Dissertations
The model of basal ganglia function proposed by Albin, Young and Penney (1989) describes two anatomically independent motor pathways, the direct and indirect. However, under normal conditions striatal dopamine (DA) is required for the expression of motor behavior, and DAergic control of the two pathways (via D1 and D2 receptors, respectively) is dependent on co-activation. We tested for a possible breakdown of D1/D2 synergism using transgenic R6/1 mice bearing the human huntingtin allele (Htt). Motor stereotypy, observed prior to the onset of HD-related symptoms, was rated on a 5-point scale following activation of: A) D1 receptors alone, B) D2 receptors …
The Nucleus Accumbens Core Dopamine D1 And Glutamate Ampa/Nmda Receptors Play A Transient Role In The Performance Of Pavlovian Approach Behavior, Veronica Dobrovitsky
The Nucleus Accumbens Core Dopamine D1 And Glutamate Ampa/Nmda Receptors Play A Transient Role In The Performance Of Pavlovian Approach Behavior, Veronica Dobrovitsky
Dissertations, Theses, and Capstone Projects
The role of the nucleus accumbens core (NAc core) continues to be redefined with newly acquired data on neurochemical mechanisms mediating the learning and performance of behavior. Previous empirical data showed that dopamine transmission at the D1 receptor (D1R) plays a transient role in the expression of learned Pavlovian approach behavior. Here we show that, prior to overtraining, dopamine activity at D1Rs specifically within the NAc core is critical for the performance of approach behavior elicited by the recently-acquired reward-paired cue. Blockade of D1Rs in the NAc core, but not the dorsomedial striatum or NAc shell, disrupted approach responses during …
Dopamine D1 Receptor Activity In The Basolateral Amygdala Is Important For Mediating Fear, Reward And Safety Discrimination Learning, Ka Ho Ng
Open Access Theses
Post traumatic stress disorder (PTSD) patients frequently show impairment in safety learning (Jovanovic, Kazama, Bachevalier, & Davis, 2012). Since the amygdala is known to be critical for emotional processing(Wassum & Izquierdo, 2015) and dopamine signaling in the amygdala is important for mediating both fear and reward learning, current experiments examined the role of dopamine signaling in the BLA in mediating both safety learning and reward seeking. We manipulated dopamine D1 receptor activity with a D1 receptor agonist (SKF 38393) or D1 receptor antagonist (SCH23390) either systemically or infused directly into the BLA 20 minutes prior to training rats in a …
Discriminative Stimulus Properties Of 1.25 Mg/Kg Clozapine In Rats: Mediation By Serotonin 5-Ht2 And Dopamine D4 Receptors, Adam J. Prus, Laura Wise, Alan L. Pehrson, Scott D. Philibin, Benny Bang-Andersen, Jørn Arnt, Joseph H. Porter
Discriminative Stimulus Properties Of 1.25 Mg/Kg Clozapine In Rats: Mediation By Serotonin 5-Ht2 And Dopamine D4 Receptors, Adam J. Prus, Laura Wise, Alan L. Pehrson, Scott D. Philibin, Benny Bang-Andersen, Jørn Arnt, Joseph H. Porter
Journal Articles
The atypical antipsychotic drug clozapine remains one of most effective treatments for schizophrenia, given a lack of extrapyramidal side effects, improvements in negative symptoms, cognitive impairment, and in symptoms in treatment-resistant schizophrenia. The adverse effects of clozapine, including agranulocytosis, make finding a safe clozapine-like a drug a goal for drug developers. The drug dis- crimination paradigm is a model of interoceptive stimulus that has been used in an effort to screen experimental drugs for clozapine-like atypical antipsychotic effects. The present study was conducted to elucidate the receptor-mediated stimulus properties that form this clozapine discriminative cue by testing selective receptor ligands …
The Relative Attenuation Of Self-Stimulation, Eating And Drinking Produced By Dopamine-Receptor Blockade, E. T. Rolls, B. J. Rolls, P. H. Kelly, S. G. Shaw, R. J. Wood, Robert H.I. Dale
The Relative Attenuation Of Self-Stimulation, Eating And Drinking Produced By Dopamine-Receptor Blockade, E. T. Rolls, B. J. Rolls, P. H. Kelly, S. G. Shaw, R. J. Wood, Robert H.I. Dale
Robert H. I. Dale
Spiroperidol, which blocks dopamine (DA) receptors, attenuated self-stimulation of the nucleus accumbens, septal area, hippocampus, anterior hypothalamus and ventral tegmental area. Dopamine is thus involved in self-stimulation of many sites (in addition to the lateral hypothalamus). The attenuation was not a simple motor impairment of the speed of bar-pressing in that the nucleus accumbens and septal self-stimulation rates were lower than those in treated animals self-stimulating at other sites (Experiment 1). Feeding was partly attenuated, and drinking was much less attenuated by the spiroperidol. Since the rats bar-pressed for brain- stimulation reward, chewed pellets to eat, and licked a tube …
Associations Between Hypothalamic-Pituitary-Adrenal Axis System Gene Variants And Cortisol Reactivity In Preschoolers: Main Effects And Gene-Environment Interactions, Haroon I. Sheikh
Electronic Thesis and Dissertation Repository
Exposure to stressful events during early development has consistently been shown to produce long lasting effects on the hypothalamic-pituitary-adrenal (HPA) axis, which may increase vulnerability to mood and anxiety disorders. Recently reported genetic association studies indicate that these disorders may be influenced, in part, by gene-environment interactions (GxE) involving polymorphisms within the corticotrophin-releasing hormone and monoaminergic system genes. However, little is known about how genetic variants and life stress work to shape children’s neuroendocrine reactivity and emerging symptoms. Therefore, the aim of this thesis is to examine main effects of candidate genes and GxE on the neuroendocrine stress response and …
A Kinder, Gentler Dopamine. . . Highlighting Dopamine's Role In Behavioral Flexibility, Jeff A. Beeler, Roshan Cools, Monica Luciana, Sean B. Ostlund, Giselle Petzinger
A Kinder, Gentler Dopamine. . . Highlighting Dopamine's Role In Behavioral Flexibility, Jeff A. Beeler, Roshan Cools, Monica Luciana, Sean B. Ostlund, Giselle Petzinger
Publications and Research
No abstract provided.
Cocaine-Induced Reinstatement Of A Conditioned Place Preference In Developing Rats: Involvement Of The D2 Receptor, Kimberly A. Badanich, Cheryl L. Kirstein
Cocaine-Induced Reinstatement Of A Conditioned Place Preference In Developing Rats: Involvement Of The D2 Receptor, Kimberly A. Badanich, Cheryl L. Kirstein
Psychology Faculty Publications
Reinstatement of conditioned place preferences have been used to investigate physiological mechanisms mediating drug-seeking behavior in adolescent and adult rodents; however, it is still unclear how psychostimulant exposure during adolescence affects neuron communication and whether these changes would elicit enhanced drug-seeking behavior later in adulthood. The present study determined whether the effects of intra-ventral tegmental area (VTA) or intra-nucleus accumbens septi (NAcc) dopamine (DA) D2 receptor antagonist infusions would block (or potentiate) cocaine-induced reinstatement of conditioned place preferences. Adolescent rats (postnatal day (PND 28–39)) were trained to express a cocaine place preference. The involvement of D2 receptors on cocaine-induced reinstatement …
The Effects Of Extended Access To Methamphetamine Self-Administration On Dopaminergic Markers In The Striatum, Joe Luevano
The Effects Of Extended Access To Methamphetamine Self-Administration On Dopaminergic Markers In The Striatum, Joe Luevano
Open Access Theses & Dissertations
Methamphetamine (METH) abuse is a persistent problem in the U.S. and abroad. Escalation of METH use among independent users occurs for a variety of physiological and psychological reasons. Methamphetamine dependence may be attributed to the rewarding effect of this drug via the dopaminergic systems of the central nervous system (CNS). The presence of METH in the CNS increases synaptic release of dopamine. This increase in dopaminergic neurotransmission is thought to be directly attributed to the rewarding effects of METH. Following METH use, compensatory changes have been found to occur in the dopaminergic system during various periods of abstinence. It is …
Dysfunctional Play And Dopamine Physiology In The Fischer 344 Rat, Stephen M. Siviy, Cynthia A. Crawford, Garnik Akopian, John P. Walsh
Dysfunctional Play And Dopamine Physiology In The Fischer 344 Rat, Stephen M. Siviy, Cynthia A. Crawford, Garnik Akopian, John P. Walsh
Psychology Faculty Publications
Juvenile Fischer 344 rats are known to be less playful than other inbred strains, although the neurobiological substrate(s) responsible for this phenotype is uncertain. In the present study, Fischer 344 rats were compared to the commonly used outbred Sprague-Dawley strain on several behavioral and physiological parameters in order to ascertain whether the lack of play may be related to compromised activity of brain dopamine (DA) systems. As expected, Fischer 344 rats were far less playful than Sprague-Dawley rats, with Fischer 344 rats less likely to initiate playful contacts with a playful partner and less likely to respond playfully to these …
Comparison Of Affective Analgesia And Conditioned Place Preference Following Cholinergic Activation Of, Elena Schifirnet
Comparison Of Affective Analgesia And Conditioned Place Preference Following Cholinergic Activation Of, Elena Schifirnet
Wayne State University Dissertations
Activation of the dopaminergic mesolimbic reward circuitry that originates in the ventral tegmental area (VTA) is postulated to preferentially suppress affective reactions to noxious stimuli (affective analgesia, AA). VTA dopamine neurons are activated via cholinergic inputs, and we have observed that microinjections of the acetylcholine agonist carbachol suppressed vocalizations of rats that occur following administration of brief (1 sec) tail-shocks (vocalization afterdischarges = VAD). VADs are a validated rodent model of pain affect. In addition, the capacity of carbachol to support reinforcement appears to be regionally dependent within VTA. Ikemoto and Wise (2002) reported that carbachol was self-administered in the …
Characterization Of The Behavioral And Neurochemical Effects Of Nicotine Withdrawal In Adolescent And Adult Rats., Luis Alberto Natividad
Characterization Of The Behavioral And Neurochemical Effects Of Nicotine Withdrawal In Adolescent And Adult Rats., Luis Alberto Natividad
Open Access Theses & Dissertations
Previous studies have demonstrated that the behavioral effects of nicotine withdrawal are lower in adolescent versus adult rats. However, the neurochemical mechanisms that mediate these developmental differences are presently unclear. Much work has shown that nicotine reward is mediated via enhanced dopamine neurotransmission in the mesolimbic pathway which originates in the ventral tegmental area (VTA) and terminates in several forebrain structures including the nucleus accumbens (NAcc). More recently, studies have shown that nicotine withdrawal produces a decrease in NAcc dopamine transmission, an effect that is believed to serve as a neurochemical marker of withdrawal in adult rodents. The goal of …
The Relative Attenuation Of Self-Stimulation, Eating And Drinking Produced By Dopamine-Receptor Blockade, E. T. Rolls, B. J. Rolls, P. H. Kelly, S. G. Shaw, R. J. Wood, Robert H.I. Dale
The Relative Attenuation Of Self-Stimulation, Eating And Drinking Produced By Dopamine-Receptor Blockade, E. T. Rolls, B. J. Rolls, P. H. Kelly, S. G. Shaw, R. J. Wood, Robert H.I. Dale
Scholarship and Professional Work - LAS
Spiroperidol, which blocks dopamine (DA) receptors, attenuated self-stimulation of the nucleus accumbens, septal area, hippocampus, anterior hypothalamus and ventral tegmental area. Dopamine is thus involved in self-stimulation of many sites (in addition to the lateral hypothalamus). The attenuation was not a simple motor impairment of the speed of bar-pressing in that the nucleus accumbens and septal self-stimulation rates were lower than those in treated animals self-stimulating at other sites (Experiment 1). Feeding was partly attenuated, and drinking was much less attenuated by the spiroperidol. Since the rats bar-pressed for brain- stimulation reward, chewed pellets to eat, and licked a tube …