A less severe impairment was observed with the tone CS. The results suggest that CS information from the LGNv and light CSs is relayed to the cerebellum through the MPN. Retrograde tracing with fluoro-gold (FG) showed that the LGNv and nucleus of the optic tract have ipsilateral projections to the MPN. Unilateral inputs to the MPN from the LGNv and nucleus of the optic tract may be part of the visual CS pathway that is necessary for visual eyeblink conditioning.”
“In the context of probabilistic AZD1480 mouse learning, previous functional magnetic resonance imaging studies have shown decreasing uncertainty
accompanying decreasing neuronal activation in task-relevant networks. Moreover, initial evidence points to a relationship between white matter structure and cognitive performance. Little is known, however, about the structural correlates underlying individual differences in activation and performance in the context of probabilistic learning. This combined functional magnetic resonance imaging diffusion tensor imaging study aimed at investigating the individual ability to reduce processing resources with decreasing uncertainty in direct relation to individual characteristics in white matter brain structure. Results showed that more successful learners, as compared with less successful learners, exhibited stronger activation decreases with decreasing selleck chemicals llc uncertainty. An increased
mean and axial diffusivity in, among others, the inferior and superior longitudinal fasciculus, the posterior part of the cingulum bundle, and the corpus callosum were detectable in less successful learners compared with more successful learners. Most importantly, there was a negative correlation between uncertainty-related activation and diffusivity in a fronto-parieto-striatal network in
less successful learners only, indicating a direct relation between diffusivity and the PLEKHM2 ability to reduce processing resources with decreasing uncertainty. These findings indicate that interindividual variations in white matter characteristics within the normal population might be linked to neuronal activation and critically influence individual learning performance. (C) 2010 IBRO. Published by Elsevier Ltd. All rights reserved.”
“Four experiments used rats to study the role of the basolateral amygdala (BLA) in the reinstatement and extinction of fear responses (freezing) to a previously extinguished conditioned stimulus (CS). In Experiment 1, BLA inactivation before pairing the extinguished CS with the shock unconditioned stimulus (US) or before US-alone exposure impaired the restoration and the reinstatement of fear responses to the extinguished CS. In Experiment 2, BLA inactivation before extinction impaired long-term inhibition of fear responses, but its inactivation before extinction of fear responses restored by CS-US pairing did not impair long-term inhibition.