Life Sciences Commons^™

Identification And Delineation Of Neuronal Pathways Underlying Hypophagia, Jing Cai

Dissertations & Theses (Open Access)

In terms of metabolism, eating disorders manifest in two extreme directions: overnutrition, which can lead to obesity, and malnutrition, which can result in underweight or even starvation. Both extremes compromise the quality of life. According to the Diagnostic and Statistical Manual of Mental Disorders-5 (DSM-5) standard, eating disorders affect up to 17.9% of young women and 2.4% of young men. Although eating disorders are primarily defined as mental disorders rather than metabolic disorders, they are intertwined with complex emotions and sensory perceptions. However, in contemporary animal research related to eating disorders and feeding behaviors, the majority of neuroscientists still examine …

Electrophysiological Signatures Of Stress Adaptability In The Bnst-Vta Pathway, Yuka Miura

Dissertations, Theses, and Capstone Projects

Chronic stress has detrimental effects on psychological and physiological health. Incapability to adapt to chronic stress can lead to depression, anxiety disorders, and addiction. The brain regions critical for reward processing share diverse physiological and molecular changes linked to depressive-like behaviors as a result of chronic stress. Cumulative evidence shows that counteraction or prevention of these alterations in neurons, occasionally in a projection-specific manner, can enhance stress adaptation or resilience.

Chronic stress induces various changes in the brain, including in the bed nucleus of the stria terminalis (BNST) and the ventral tegmental area (VTA). The neural projections from the BNST …

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.

Mapping A Pup-Responsive Pathway From The Medial Preoptic Area To The Ventral Tegmental Area., Matias Andina

Masters Theses

Maternal behavior is the complex array of caregiving behaviors females display towards offspring. In rats, the transition to motherhood depends on the action of various hormones, especially estradiol near parturition, which primes the maternal circuitry to respond to pups upon first encounter at parturition with appropriate maternal behavior. Although virgin rats avoid pups, new mothers are highly motivated to interact with pups, and their maternal behavior depends on the functional interaction between the medial preoptic area (mPOA) and the ventral tegmental area (VTA). However, a precise mapping of the VTA-projecting mPOA neurons remains to be elucidated. To determine whether pup-responsive …

The Role Of Glutamate Neurotransmission In The Ventral Tegmental Area In The Expression Of Conditioned Approach Learning, Priscila Hachimine-Merli

Dissertations, Theses, and Capstone Projects

Conditioned stimuli (CSs) come to function as CSs by acquiring the capacity to activate the same mesocorticolimbic dopamine (DA) neurons activated by primary rewards, producing conditioned activation of these neurons and their associated motivational states. This model stipulates that CSs activate mesocorticolimbic DA systems through the activation of glutamate receptors on DA neurons in the ventral tegmental area (VTA). We tested the hypothesis that glutamate receptor stimulation in the VTA is necessary for the expression of conditioned approach. Rats were tested in a conditioned approach protocol that consisted of 7 consecutive conditioning sessions (light presentations and food were paired), one …

Cocaine And Mefloquine-Induced Acute Effects In Ventral Tegmental Area Dopamine And Gaba Neurons, David Wilbanks Allison

Theses and Dissertations

The aim of the two studies presented here was to evaluate the effects of cocaine and mefloquine (MFQ) on γ-aminobutyric acid (GABA) and dopamine (DA) neurons in the ventral tegmental area (VTA). Cocaine: In vivo, lower doses of intravenous cocaine (0.25-0.5 mg/kg), or methamphetamine (METH), enhanced VTA GABA neuron firing rate via D2/D5 receptor activation. Higher cocaine doses (1.0-2.0 mg/kg) inhibited their firing rate. Cocaine and lidocaine inhibited the firing rate and spike discharges induced by stimulation of the internal capsule (ICPSDs) at dose levels 0.25-2 mg/kg (IC50 1.2 mg/kg), but neither DA nor METH reduced ICPSDs. In VTA …

Brain Stimulation Reward Is Integrated By A Network Of Electrically-Coupled Gaba Neurons, Matthew Brian Lassen

Theses and Dissertations

Although it is well-established that animals will self-stimulate electric current to various diverse brain structures, the neural substrate of brain stimulation reward (BSR) has eluded identification since its discovery more than a half-century ago. We show that GABA neurons in the midbrain, hypothalamus and thalamus express connexin-36 (Cx36) gap junctions and couple electrically with dopamine application or by stimulation of the internal capsule (IC), which also supports self-stimulation. The threshold for responding for self-stimulation of the IC is the threshold for coupling between these GABA neurons, the degree of responding for IC ICSS is proportional to the magnitude of electrical …