Neuroscience and Neurobiology Commons^™

Quantifying Psychostimulant-Induced Sensitization Effects On Dopamine And Acetylcholine Release Across Different Timescales, Georg Lange

Dissertations, Theses, and Capstone Projects

Drug-induced behavioral sensitization describes the phenomenon that behavioral response to a drug of abuse is getting stronger if the same psychostimulant is delivered multiple times which is much more pronounced if done in the same environmental context. A proposed neural basis is the formation of an association between contextual cues and the rewarding drug which is mediated by dopamine. Dopamine operates at different timescales and to fully understand dopamine sensitization, it is necessary to investigate dopamine release at slow (tens of minutes) but also faster (sub-second) timescales. But creating a holistic view has been difficult due to a lack of …

Organization And Development Of Cholinergic Input To The Mouse Visual Thalamus., Guela Sokhadze

Electronic Theses and Dissertations

Cholinergic signaling plays a vital role in modulating the flow of sensory information through thalamic circuits in a state-dependent manner. In the dorsal lateral geniculate nucleus (dLGN), the thalamic visual relay, release of acetylcholine (ACh) contributes to enhanced thalamocortical transfer of retinal signal during behavioral states of arousal, wakefulness, and sleep/wake transitions. Moreover, ACh modulates activity of the thalamic reticular nucleus (TRN), a structure which provides inhibitory input to dLGN. While several cholinergic nuclei have been shown to innervate dLGN and TRN, it is unclear how projections from each area are organized. Furthermore, little is known of how or when …

The Role Of Cholinergic Neurotransmission In Sensory Filtering And Sensorimotor Gating, Erin Azzopardi

Electronic Thesis and Dissertation Repository

At every moment, our brain is bombarded with sensory information. How we filter and process sensory information is critical for daily functioning and cognition. Examples of sensory filtering include habituation (a progressive decrease in responding) and prepulse inhibition (PPI, gating of responding). Our aim is to understand the differential role acetylcholine (ACh) plays in these processes.

To study this we used both reflexive (acoustic startle response: ASR) and non-reflexive (locomotor) behaviours. PPI is hypothesized to occur via inhibitory cholinergic projections from the Pedunculopontine Tegmental Nucleus (PPT) to the startle pathway. The role of ACh in habituation of reflexive and non-reflexive …

Cognitive Roles Of Anterior And Posterior Pedunculopontine Tegmentum Subregions, Jordan C. Robinson

Electronic Thesis and Dissertation Repository

The pedunculopontine tegmentum (PPT) is part of the mesopontine cholinergic system with distinct anterior and posterior subdivisions. With fast sensory input and descending connections to brainstem locomotor centers, we predict posterior PPT (pPPT) mediates prepulse inhibition of acoustic startle reflex, a form of sensorimotor gating that affects attentional processes. Similar to pPPT cholinergic projections to ventral tegmental area, we predict anterior PPT cholinergic input to substantia nigra regulates dopamine release in striatum, which is important for reinforcement learning. We lesioned the PPT bilaterally in male Sprague Dawley rats with ibotenic acid. Posterior cholinergic cell loss was significantly correlated with prepulse …