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 Behavioural Phenotype Of Pthr175-Tau Expression In The Hippocampus Of Female Adult Sprague Dawley Rats, Jason J. Gopaul

Electronic Thesis and Dissertation Repository

Amyotrophic lateral sclerosis with cognitive impairment (ALSci) can be characterized by pathological inclusions of microtubule associated protein tau (tau) uniquely phosphorylated at Thr175 (pThr175-tau). The purpose of this study was to characterize the behavioural consequences of expressing a pseudophosphorylated tau mimic of pThr175-tau (Thr175Asp-tau) in rat hippocampus. Expression was hypothesized to lead to pathological tau fibril formation resulting in cognitive and behavioural deficits. Expression was accomplished in female Sprague Dawley rats through stereotactic inoculations of recombinant adeno-associated virus (rAAV9) vector with human tau gene. Pathological tau fibrillary structures were identified, but behavioural testing up to 12 months post-surgery revealed no …