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Neural sensitivity to basic elements of the visual scene changes dramatically as information is handed from the thalamus to the primary visual cortex in cats. Famously, thalamic neurons are insensitive to stimulus orientation whereas their cortical targets easily resolve small changes in stimulus angle. There are two main types of cells in the visual cortex, simple and complex, defined by the s...

Inferotemporal (IT) neurons exhibit a substantial degree of invariance with respect to translation of images used as visual stimuli. Through theoretical and computer-modeling methods, we show how translation-invariant receptive fields, like those of IT neurons, can be generated from the responses of V4 neurons if the effects of attention are taken into account. The model incorporates a recently...

This article gives an overview of a normative computational theory of visual receptive fields, by which idealized shapes of early spatial, spatio-chromatic and spatiotemporal receptive fields can be derived in an axiomatic way based on structural properties of the environment in combination with assumptions about the internal structure of a vision system to guarantee consistent handling of imag...

This study is the first to investigate: (a) 'temporal performance fields,' whether the speed of information accrual differs for different locations at a fixed eccentricity, and (b) whether covert attention modulates temporal dynamics differentially at isoeccentric locations. Using the speed accuracy tradeoff (SAT) procedure, we derived conjoint measures of how isoeccentric locations and precuei...

The effects of emotionality and length on lateralized lexical decision of abstract nouns were investigated in 41 normal and three commissurotomized subjects. Emotionality had the same effect in both visual fields: Emotional words were responded to more accurately than neutral words. Length had different effects in the two visual fields: The accuracy of lexical decisions in the left visual field...

Simple cells in the primary visual cortex respond selectively to oriented stimuli. It has been proposed that such feature detecting neurons should generate a sparse representation of the visual world and orientation selective receptive fields are in this sense optimal spatial filters for “natural” visual environments. In this contribution we show that a competitive Hebbian development model dri...

Recently it has been pointed out that in simple animals like flies a motor neuron can have a visual receptive field [1]. Such receptive fields directly generate behaviour which, through closing the perception-action loop, will feed back to the sensors again. In more complex animals an increasingly complex hierarchy of visual receptive fields exists from early to higher visual areas, where visua...

A large choroidal metastasis was diagnosed in the right eye of a 44-year-old man referred for admission to hospital because of 'retinal detachment.' At the same time in the second, symptomless, eye a very small metastasis was observed. Close follow-up during the next month showed an extremely rapid deterioration of visual acuity and visual field in this eye. This is thought to be characteristic...

Recent physiological recording studies in monkeys have suggested that the frontal eye fields (FEFs) are involved in visual scene analysis even when eye movement commands are not required. We examined this proposed function of the human frontal eye fields during performance of visual search tasks in which difficulty was matched and eye movements were neither necessary nor required. Magnetic stim...