Cortical circuitry

Englund, U., Bjorldund, A., Wictorin, K., Lindvall, O. and Kokaia, M. Grafted neural stem cells develop into functional pyramidal neurons and integrate into host cortical circuitry. Proc. Natl Acad. Sci. U.S.A. 99 17089-17094,2002. 

Lewis DA. 1998. Chandelier cells Shedding light on altered cortical circuitry in schizophrenia. Mol Psychiatry 3 468-471. 

The development of serotonergic innervation to the cerebral cortex has been characterized in neonatal rats by immunohistochemical techniques and autoradiographic imaging. These experiments demonstrate early serotonergic innervation that could be involved in a transient physiological role in sensory areas of the cortex or exert a trophic influence on the development of cortical circuitry and thalamocortical connections [76]. 

Critical periods are those in which the synaptic circuitry of a given brain region becomes stabilized in a functionally optimized conformation. The cerebral cortex and other brain structures contain functional maps for the activities characteristic of a species. The best example is the ocular dominance columns and other physical and functional characteristics of the circuitry within the visual cortical system that process information derived from the left and right visual fields, producing a map of the visual world. Other internal maps exist for the body (somatosensory, motor corti-... 

Geula, C. (1998) Abnormalities of neural circuitry in Alzheimer s disease hippocampus and cortical cholinergic innervation, hieu-rology 51 S18—S29 discussion S65-67. 

Functional neuroimaging studies provide strong evidence for dysfunction of the cortical-striatal-thalamocortical (CSTC) circuitry. Symptoms of OCD are associated with increased activity in orbitofrontal cortex in neutral state (Swedo et ah, 1989b Baxter, 1994 Saxena et ah, 1998). Increased activity was also noted in some of these studies in anterior cingulate gyrus, caudate nucleus, and thalamus. Horwitz et al. (1991) found that the pattern of intercorrelations between various brain regions in patients with OCD differed from that of controls. 

Two lines of evidence implicate the serotonin system. First, it has a significant role at several sites in the circuitry connecting the frontal cortical and the basal ganglia locations. Second, agents that benefit OCD have potent serotonin effects (e.g., clomipramine, SSRIs). 

Ang CW, Carlson GC, Coulter DA. 2005. Hippocampal CA1 circuitry dynamically gates direct cortical inputs preferentially at theta frequencies. J Neurosci 25 9567-9580. 

The ability to encode new information into memory and to retrieve previously stored information from memory is impaired in schizophrenia. Several models have proposed abnormalities of cortical-hippocampal circuitry as the mechanism for the abnormal mental representations seen in schizophrenia (Roberts, 1963 Venables, 1992 Hemsley, 1993 Talamini et al., 2005 Siekmeier et al., 2007). 

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