Search results for "Neostriatum"
showing 3 items of 13 documents
6-Hydroxydopamine lesioning differentially affects α-synuclein mRNA expression in the nucleus accumbens, striatum and substantia nigra of adult rats
2002
The effect of a unilateral 6-hydroxydopamine (6-OHDA) lesion and/or repeated administration of levodopa (L-DOPA) to normal and 6-OHDA-lesioned rats on alpha-synuclein mRNA expression was investigated by in situ hybridization histochemistry. A 6-OHDA lesion of the nigro-striatal pathway alone, confirmed by the loss of nigral tyrosine hydroxylase mRNA expression, markedly decreased alpha-synuclein mRNA in the lesioned substantia nigra (SN). In contrast, the levels of alpha-synuclein mRNA in the denervated striatum and nucleus accumbens were not altered. Chronic administration of L-DOPA to normal or 6-OHDA-lesioned rats had no effect on alpha-synuclein mRNA expression in the SN, striatum or nu…
Reservoir computing model of prefrontal cortex creates novel combinations of previous navigation sequences from hippocampal place-cell replay with sp…
2019
As rats learn to search for multiple sources of food or water in a complex environment, they generate increasingly efficient trajectories between reward sites. Such spatial navigation capacity involves the replay of hippocampal place-cells during awake states, generating small sequences of spatially related place-cell activity that we call “snippets”. These snippets occur primarily during sharp-wave-ripples (SWRs). Here we focus on the role of such replay events, as the animal is learning a traveling salesperson task (TSP) across multiple trials. We hypothesize that snippet replay generates synthetic data that can substantially expand and restructure the experience available and make learni…
Stimulant-induced adaptations in neostriatal matrix and striosome systems: Transiting from instrumental responding to habitual behavior in drug addic…
2005
Abstract Converging evidence indicates that repeated exposure to motor stimulants such as cocaine and amphetamine produces marked alterations in network responsiveness of striatal neurons to subsequent challenge with the same stimulant drug. Such alterations, which correlate with persistent patterns of repetitive behavior, associate with distinct compartmental changes in the neostriatum. Striatal matrix system neurons undergo “silencing” following repeated drug challenges, allowing striosome system neurons to exhibit preferential activation. Matrix neurons are innervated by sensory and motor areas of neocortex and are activated in the course of on-going, adaptive behavior. Inactivation of m…