25 research outputs found
Is transjugular intrahepatic portasystemic shunt a panacea for the complications of portal hypertension?
Influence of CO 2 on the micro-structural properties of spider dragline silk: X-ray microdiffraction results
Model-independent analysis of the differential cross section for the reaction n+d??0+t at medium energies
Development of resistance byEnterobacter cloacae during therapy of pulmonary infections in intensive care patients
AII amacrine cell population in the rabbit retina: Identification by parvalbumin immunoreactivity
How patterns of bleached rods and cones become visual perceptual experiences: A proposal
In an attempt to increase information about how mammalian visual systems create a perceptual experience out of a retinal photochemical bleach pattern, this article brings together recent rat physiological data acquired with large electrodes, an old cat behavioral experiment, and two complex human behaviors: reading and the reversible blindness people experience when the scene being viewed is stabilized on the retinal surface. The outcome suggests this juxtaposition of disparate data sets has been logical, reasonable, and informative. The link between rats and reading is the fact that both rat and human retinas convert bleach patterns into ganglion cell volleys 3 times a second. The probable trigger for these episodic retinal volleys is a more or less abrupt change in the pattern of bleached rods and cones, and we claim the absence of this trigger when the image is stabilized is responsible for the blindness. The cat behavioral experiment correlates performance on visual discrimination tasks with the number of nerve fibers remaining after lesions of the optic tract. The analysis of the result, which shows that as few as 2% of the normal number of nerve fibers supports perfect performance of such tasks, prompts the concept of a second dynamic visual system, operating in parallel with the anatomical nervous system pictured in the textbooks. The dynamic visual system model, which brings into the foreground important old facts that have been neglected and integrates them with new data, offers a synthesis that may be useful in interpreting classical visual behavioral phenomena