AIM To determine in vivo whether the lateral geniculate nucleus (LGN) undergoes atrophy in patients with glaucoma and vision loss compared with normal subjects. METHODS Following institutional St Michael's Hospital Research Ethics Board approval, a prospective and masked neuroimaging study was conducted on glaucoma patients with visual-field defects affecting both eyes (n = 10) and age-matche...

Background and Aim. We evaluated the usefulness of background coloration (BC), a color change in the area between intrapapillary capillary loops (IPCLs) in the early esophago-pharyngeal lesions using NBI with magnificaiton. Methods. Between April 2004 and March 2010, a total of 294 esophago-pharyngeal lesions were examined using NBI with magnification, and the presence of BC and IPCL patterns w...

Monocular deprivation early in postnatal development leads to anatomical and physiological changes in the lateral geniculate nucleus (LGN) and visual cortex. Many of these changes are dependent upon activation of the NMDA receptor. We have examined the role of visual experience in modifying NMDAR1 subunit expression in the LGN of animals reared with various forms of visual deprivation. Followin...

Two long-standing questions in neuroscience are how sleep promotes brain plasticity and why some forms of plasticity occur preferentially during sleep vs. wake. Establishing causal relationships between specific features of sleep (e.g., network oscillations) and sleep-dependent plasticity has been difficult. Here we demonstrate that presentation of a novel visual stimulus (a single oriented gra...

The lateral geniculate nucleus (LGN) is the primary thalamic nucleus that relays visual information from the retina to the primary visual cortex (V1) and has been extensively studied in non-human primates. A key feature of the LGN is the segregation of retinal inputs into different cellular layers characterized by their differential responses to red-green (RG) color (L/M opponent), blue-yellow ...

A distinguished line-up of scholars recently got together to stir up discussion about the physiological basis for color and have, with a simple manipulation of decades-old data, challenged one of the fundamental tenets of our current understanding of the neurobiology of color (1). Understanding color is not easy. Newton made some headway, but his demonstration of color’s physical basis provided...

Orientation selectivity is a property of mammalian primary visual cortex (V1) neurons, yet its emergence along the visual pathway varies across species. In carnivores and primates, elongated receptive fields first appear in V1, while in lagomorphs such receptive fields emerge earlier, in the retina. Here we examine the mouse visual pathway and reveal the existence of orientation selectivity in ...

The response of a neuron in striate cortex to an optimally oriented stimulus is suppressed by a superimposed orthogonal stimulus. The neural mechanism underlying this cross-orientation suppression (COS) may arise from intracortical or subcortical processes or from both. Recent studies of the temporal frequency and adaptation properties of COS suggest that depression at thalamo-cortical synapses...