Receptive field

About: Receptive field is a research topic. Over the lifetime, 8537 publications have been published within this topic receiving 596428 citations.

Dynamic predictive coding by the retina.

Abstract: Retinal ganglion cells convey the visual image from the eye to the brain. They generally encode local differences in space and changes in time rather than the raw image intensity. This can be seen as a strategy of predictive coding, adapted through evolution to the average image statistics of the natural environment. Yet animals encounter many environments with visual statistics different from the average scene. Here we show that when this happens, the retina adjusts its processing dynamically. The spatio-temporal receptive fields of retinal ganglion cells change after a few seconds in a new environment. The changes are adaptive, in that the new receptive field improves predictive coding under the new image statistics. We show that a network model with plastic synapses can account for the large variety of observed adaptations.

Segmental and supraspinal actions on dorsal horn neurons responding to noxious and non-noxious skin stimuli.

Abstract: 1. (1) Single dorsal horn neurons have been recorded extracellularly in 8 anesthetized (pentobarbital-Na) cats and in 1 unanesthetized decerebrated cat. The animals were either spinalized by transection of the cord at L 1 (6 experiments) or a cold block was used for reversible spinalization at L 1 (3 experiments). 2. (2) Sixty-five units were recorded in the dorsal horn and in the dorsolateral funiculus which could be excited by electrical stimulation of the ipsilateral plantar nerves and by natural stimulation of the skin in the foot region. The recording position of the microelectrode was verified histologically. 3. (3) According to their excitability by electrical stimulation of the afferent nerve fibers and by natural stimulation of the receptive fields, 2 major classes of units could be distinguished in the spinalized cat. Class 1 cells were excited by electrical stimulation of myelinated axons (group II) in the plantar nerves. Four out of 9 could be excited by low threshold cutaneous mechanoreceptors; 5 had input probably from deep receptors. Class 2 cells , which were more than twice as common as class 1 cells, could, like the latter, be excited by electrical stimulation of group II myelinated afferent fibers in the plantar nerves, but in addition, were excited by electrical stimulation of C-fibers. 4. (4) When stimulated naturally, virtually all of the class 2 cells received an excitatory input from low threshold cutaneous mechanoreceptors and also from receptors excited by noxious radiant heat stimulation in their receptive fields. They responded to noxious heating in a quantitatively similar manner as the primary C-heat nociceptors.

Selective Sensitivity to Direction of Movement in Ganglion Cells of the Rabbit Retina

Abstract: Among the ganglion cells in the rabbit's retina there is a class that responds to movement of a stimulus in one direction, and does not respond to movement in the opposite direction. The same directional selectivity holds over the whole receptive field of one such cell, but the selected direction differs in different cells. The discharge is almost uninfluenced by the intensity of the stimulus spot, and the response occurs for the same direction of movement when a black spot is substituted for a light spot.

A Neural Map of Auditory Space in the Owl

Abstract: Auditory units that responded to sound only when it originated from a limited area of space were found in the lateral and anterior portions of the midbrain auditory nucleus of the owl (Tyto alba). The areas of space to which these units responded (their receptive fields) were largely independent of the nature and intensity of the sound stimulus. The units were arranged systematically within the midbrain auditory nucleus according to the relative locations of their receptive fields, thus creating a physiological map of auditory space.