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dc.contributor.supervisor Gruber, Aaron J.
dc.contributor.supervisor McNaughton, Bruce L.
dc.contributor.author Molina, Leonardo A.
dc.date.accessioned 2013-09-24T03:47:23Z
dc.date.available 2013-09-24T03:47:23Z
dc.date.issued 2012
dc.identifier.uri https://hdl.handle.net/10133/3264
dc.description xi, 42 leaves : ill. ; 29 cm en_US
dc.description.abstract NMDA receptor antagonists such as Ketamine and PCP are potent psychoactive drugs used recreationally. This class of drug induces a number of phenomena in humans similar to those associated with schizophrenia including reduced selective attention, altered working memory, thought disorders and hallucinations. These psychotomimetic drugs have thus been used as a longstanding model to study this disease in animals. Importantly, such animal models allow for recording of brain activity using invasive techniques that are inappropriate in humans. Previous electrophysiological studies have shown that MK-801, a potent non-competitive NMDA receptor antagonist, increases gamma-frequency oscillations and produces a state of disinhibition in the prefrontal cortex of rats wherein the activity of putative excitatory pyramidal neurons increases while the activity of putative inhibitory interneurons decreases. These features are relevant to schizophrenia because molecular evidence suggests dysfunction of inhibitory cortical interneurons, while electroencephalographic recordings show altered gamma-frequency oscillations in this disease. It has been hypothesized that the disinhibited cortical state produces “noisy” information processing, but this has not been directly observed in the interaction of neuronal firing in either humans or animal models. We therefore tested this hypothesis by examining the synchronization of neural activity in the NMDA receptor antagonist model of schizophrenia. We used high-density electrophysiological recordings in the medial prefrontal cortex of freely moving rats before and after systemic injection of MK-801. Analysis of these recordings revealed that drug administration: (i) increases gamma power in field potentials in a manner dissociated from increased locomotion; (ii) does not change the gamma power in multi-unit activity; (iii) decreases spike synchronization among putative pyramidal neurons in the gamma range (30ms), and despite of this it (iv) does not change the synchronization between gamma-range field potentials or between sum-of-spikes and field potentials. These effects in synchronization may be revealing of potent cognitive effects associated with NMDA receptor antagonism, and may reflect impaired communication processing hypothesized to occur in schizophrenia. en_US
dc.language.iso en_US en_US
dc.publisher Lethbridge, Alta. : University of Lethbridge, Dept. of Neuroscience, c2012 en_US
dc.relation.ispartofseries Thesis (University of Lethbridge. Faculty of Arts and Science) en_US
dc.subject Methyl aspartate -- Antagonists -- Research en_US
dc.subject Methyl aspartate -- Receptors -- Research en_US
dc.subject Schizophrenia -- Research en_US
dc.subject Rats as laboratory animals en_US
dc.title Alteration of neural dynamics in the rat medial prefrontal cortex by an NMDA antagonist en_US
dc.type Thesis en_US
dc.publisher.faculty Arts and Science en_US
dc.publisher.department Department of Neuroscience en_US
dc.degree.level Masters


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