Disease relevance of Visual Cortex

• Prompted by the observation of decreased glucose metabolism in the striate and extrastriate visual cortex in a patient with opsoclonus, we studied the influence of involuntary eye movements on visual cortex activity [1].
• Mitochondrial encephalomyopathy: elevated visual cortex lactate unresponsive to photic stimulation--a localized 1H-MRS study [2].
• Measurement of metabolite levels in the occipital visual cortex in six normal subjects and six patients disclosed high lactate levels in the five patients who had experienced a migraine attack within the previous 2 months [3].
• During hypercapnia established by an end-tidal CO2 increase of 1.46 kPa, CBF in the visual cortex increased by 47.3 +/- 17.3% (mean +/- SD; n = 9), and deltaR2* was -0.478 +/- 0.147 sec(-1), which corresponds to BOLD signal change of 2.4 +/- 0.7% with a gradient echo time of 50 msec [4].
• Functional implications of mouse hereditary retinal degeneration have been studied at the level of the superior colliculus and visual cortex in the C57BL/6J-le rd strain [5].

Psychiatry related information on Visual Cortex

• Single- and double-label 2-deoxyglucose autoradiographs show further that slow-wave sleep differentially depresses visually evoked activity in the deeper layers of the visual cortex [6].
• Moreover, monocular deprivation remained effective in mice lacking mGluR2, and receptor expression levels were unchanged during the critical period in wild-type mice, indicating that experience-dependent plasticity is independent of LTD induction in visual cortex [7].
• Compared to placebo, rivastigmine produced only a small and non-significant improvement in task accuracy across all conditions with no change in response latency, and increased activity in the extrastriate visual cortex in areas associated with visual and spatial attention but not in any region within the working memory network [8].
• NMDA, AMPA, and benzodiazepine binding site changes in Alzheimer's disease visual cortex [9].
• Under our experimental conditions, sensory deprivation did not significantly alter GAP-43 levels in the visual cortex [10].

High impact information on Visual Cortex

• Switch-like behavior is not seen in the visual cortex, but might be seen in the hippocampus if the relative density of NMDA receptors there was higher than in the visual cortex.(ABSTRACT TRUNCATED AT 400 WORDS)[11]
• The visual cortex is thus served by many cortico-cortical connections to form a network of considerable complexity [12].
• Dark-rearing delays the loss of NMDA-receptor function in kitten visual cortex [13].
• A particularly striking example is the pattern of glomeruli in the olfactory bulbs; other instances are columns and 'blobs' in the visual cortex, barrels and columns in the somatosensory cortex, and striasomes and cell islands in the neostriatum [14].
• Thus, calbindin occurs in the primate striate cortex in a pattern almost complementary to that displaying strong cytochrome c-oxidase activity [15].

Chemical compound and disease context of Visual Cortex

• The ocular dominance histograms for cells in the visual cortex were indistinguishable from those of kittens that were monocularly deprived for a similar period in the "critical period" and that had normal amounts of noradrenaline in their visual cortex [16].
• We have studied the expression of the neuronal serine protease inhibitor neuroserpin in the primary visual cortex of mice from birth until the end of the critical period by means of reverse transcription polymerase chain reaction and in situ hybridization [17].
• In addition, the changes in NMDA expression in the visual cortex provide a greater understanding of the neural mechanisms that underlie the development of amblyopia and the potential for visual recovery [18].
• Whereas the bradycardia responses to the CS+ quickly extinguished in the group that had control lesions in the visual cortex, the auditory cortex lesion group continued to exhibit significantly larger bradycardiac HR CRs to the CS+ relative to the CS- during all 7 days of extinction [19].
• These results, together with the previously established properties of C1 and C2, suggest that the early stages of contour-specific processing in the visual cortex have relatively short response latencies and durations and are uninfluenced by the subsequent presentation of metacontrast masking stimuli [20].

Biological context of Visual Cortex

• Long-term potentiation and NMDA receptors in rat visual cortex [21].
• Autoradiographic representation of the local rates of cerebral glucose utilization and local cerebral functional activity by means of the [14C]deoxyglucose technique reveals the existence of the ocular dominance columns in the striate cortex of the monkey in the first day of life [22].
• In this issue of Neuron, Mazer and Gallant analyze neural activity in higher-level visual cortex during this kind of active visual exploration, and they demonstrate a localized enhancement of visual responses that predicts the target of the upcoming eye movement [23].
• Here, we establish a fundamental role for type 2 metabotropic glutamate receptors (mGluR2) in long-term depression (LTD) of synaptic transmission within primary visual cortex [7].
• The glucose change was used to calculate the increase of glucose cerebral metabolic rate in the visual cortex region for individual subjects by using the Michaelis-Menten model of glucose transport on the assumption of constant transport kinetics [24].

Anatomical context of Visual Cortex

• We have examined the hypothesis that the segregation of LGN axon terminals into ocular dominance (OD) patches in layer 4 of the visual cortex requires neurotrophins, acting as signals to modulate the pattern of synaptic connectivity [25].
• In postnatal rat brain, CDF/LIF mRNA is localized selectively in two parts of the visual system, visual cortex and superior colliculus [26].
• The visual cortex, pancreas, mammary gland, preimplantation embryo, and placenta contain the largest number of differentially expressed transcripts, 25% of which are previously undescribed loci [27].
• Depolarization with 40-60 mM K+ was used to analyze the activity of Ca2+ VOCs in Indo-1-loaded astrocytes in acute slices from the visual cortex and the CA1 hippocampal region of developing rats [28].
• In rats that performed a well-learned nose-poke response for water reward, c-fos mRNA levels were broadly increased, relative to values in home cage-control rats, in visual cortex, superior colliculus, olfactory bulb, and, to comparable levels, regions CA3 and CA1 of hippocampus; hybridization was not increased in the dentate gyrus [29].

Associations of Visual Cortex with chemical compounds

• NMDA receptors in the visual cortex of young kittens are more effective than those of adult cats [30].
• Aspartate and glutamate as possible neurotransmitters of cells in layer 6 of the visual cortex [31].
• We used two strategies to deplete cortical NA: the first, pioneered by Kasamatsu el al., utilized osmotic minipumps to deliver 6-OHDA to visual cortex; the second involved systemic neonatal injections of 6-OHDA, a technique which has proved effective in rodents [32].
• Transient increase in muscarinic acetylcholine receptor and acetylcholinesterase in visual cortex on first exposure of dark-reared rats to light [33].
• Physiological evidence that the 2-deoxyglucose method reveals orientation columns in cat visual cortex [34].

Gene context of Visual Cortex

• Combgap is thus a tissue-specific relay between Wingless and its target genes for the determination of cell fate in the visual cortex [35].
• These data reveal that NMDAR subunit composition in the visual cortex is remarkably dynamic and bidirectionally regulated by sensory experience [36].
• TrkB-IgG or K252a itself completely blocked LTP, suggesting that endogenous BDNF or another TrkB ligand plays a role in LTP in the developing visual cortex [37].
• We examined the activities of ERK, JNK/SAPK, and p38 MAPK along with their nuclear targets (Elk-1 and c-Jun) in rat visual cortex after light stimulation [38].
• In the present study, we have examined the time course of NMDA receptor changes and how they correlate with the critical period of ocular dominance plasticity in the visual cortex of a highly binocular animal, the ferret [39].

Analytical, diagnostic and therapeutic context of Visual Cortex

• We have used 2-deoxyglucose autoradiography to investigate the development of cat striate cortex [40].
• Here, we map the visual cortex (V1) in mice deficient for ephrin-A2, -A3, and -A5 functionally, using intrinsic signal optical imaging and microelectrode recording, and structurally, by anatomical tracing of thalamocortical projections [41].
• Using newly developed 1H NMR spectroscopic techniques that allow measurement of lactate in vivo, we detected lactate elevations of 0.3-0.9 mM in human visual cortex during physiologic photic stimulation [42].
• We studied one mitochondrial-encoded mRNA [subunit I (COI)], two nuclear-encoded mRNAs (COIV, COVIII), and mtDNA, using in situ hybridization to determine their distributions in monkey hippocampus, cerebellum, and primary visual cortex [43].
• Measuring oxygen consumption (CMR O2 ) with positron emission tomography, the authors demonstrated increased CMR O2 during sustained stimulation of visual cortex with a complex stimulus [44].

References