Life Sciences Commons^™

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 …

The Role Of Forebrain Cholinergic Signalling In Regulating Hippocampal Function And Neuropathology, Mohammed Al-Onaizi

Electronic Thesis and Dissertation Repository

Cholinergic dysfunction has been associated with cognitive abnormalities in a variety of neurodegenerative and neuropsychiatric disorders, including Alzheimer’s Disease (AD). Cumulative use of drugs with anticholinergic activity is associated with increased risk for dementia and AD. Also, cholinergic function has been implicated in predicting the development of key neuropathological hallmarks seen in AD. However, the relationship between cholinergic dysfunction and conservation of cognitive ability as well as neuronal cell maintenance is not fully understood. Here, we tested how information processing and distinct molecular mechanisms associated with AD are regulated by cholinergic tone in genetically-modified mice in which cholinergic transmission was …