Cortico cortical

A global view of consciousness is that it is generated throughout the entire brain, as a result of synchronisation of relevant neural networks. Specific systems or regions—for example the cerebral cortex, brainstem reticular formation and thalamic nuclei—may be key anatomical integrators. Areas with the most widespread interconnections are pivotal, and on this basis the cortex and thalamus are more relevant than cerebellum and striatum for example. Frontal cortex for example connects with every other brain region, both in terms of input and output, with 80% of such connections accounted for by cortico-cortical connections. Thalamic intralaminar nuclei are, in conjunction with the reticular nucleus, reciprocally connected to all cortical areas. By contrast the cerebellum has very few output pathways and striatal-cortical input is (via the thalamus) confined to frontal lobe. 

Glutamatergic neurons are widely distributed throughout the entire brain. Most glutamatergic neurons are so-called projection neurons their axon projects into distant brain regions. Prominent glutamatergic pathways are the connections between different regions of the cerebral cortex (cortico-cortical projections), the connections between thalamus and cortex, and the projections from cortex to striatum (extrapyramidal pathway) and from cortex to brain stem/spinal chord (pyramidal pathway). 

Parnas J, Bovet P, Innocenti GM. 1996. Schizophrenic trait features, binding, and cortico-cortical connectivity A neu-rodevelopmental pathogenetic hypothesis. Neurol Psychiatry Brain Res 4 185-196. 

Association Connections Cortico-cortical projections within PC are extensive and exhibit laminar... 

Cellular heterogeneity of the corticostriatal projection could also help to explain the absence of a single simple rule governing the convergence of corticostriatal inputs. Rules based on cortico-cortical connections, like that suggested by Yeterian and van Hoesen... 

Thatcher R. W., Krause P. 1. and Hrybyk M. 1986. Cortico-cortical associations and EEG coherence A two-compartmental model. Electroencephalogr. CUn. Neurophysiol. 64 123-143 Toga A. W., Thompson P. M. and Sowell E. R. 2006. Mapping brain maturation. Trends Neurosci. 29 148-159... 

The post-surgery survival period coincides with the time required for the tracer to be retrogradely transported from the injection point, where it is taken up by axon terminals, to the parent cell bodies. To label cortico-cortical associative neurons, 72-96 h represent the optimal survival time. During this period, animals must be monitored on a regular basis, according to the rules established by the Animal Care Facility of your institution, in order to minimize stress, discomfort, and post-surgical pain. 

Fig. 1 Retrogradely labeled cortico-cortical neurons in layer 2/3 of the sensorimotor rat cortex. Note the Golgi-like labeling of the basal and apical dendrites. Arrowheads indicate the axon initial segment. Note also the labeling of dendritic spines (especially evident in (a)). Scale bar 25 pm...

Giannetti S, Gaglini PD, Rocco F et al (2000) Organization of cortico-cortical associative projections in a rat model of microgyria. Neuroreport 11 2185-2189... 

Granato A, Di Rocco F, Zumbo A et al (2003) Organization of cortico-cortical associative projections in rats exposed to ethanol during early postnatal life. Brain Res Bull 60 339-344... 

Minciacchi D, Del Tongo C, Carretta D et al (2010) Alterations of the cortico-cortical network in sensori-motor areas of dystrophin deficient mice. Neiu-osdence 166 1129-1139... 

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