Receptive field

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

Neural Basis of Orientation Perception in Primate Vision

Abstract: Orientational differences in human visual acuity can be related parametrically to the distribution of optimal orientations for the receptive fields of neurons in the striate cortex of the rhesus monkey. Both behavioral measures of acuity and the distribution of receptive fields exhibit maximums for stimuli horizontal or vertical relative to the retina; the effect diminishes with distance from the fovea. The anisotropy in the neuronal population and in visual acuity appear to be determined by postnatal visual experience.

An electrophysiological study of dorsal horn neurons in the spinal cord of rats with an experimental peripheral neuropathy.

Abstract: 1. Extracellular single-unit recordings have been made from 295 dorsal horn neurons in the lumbar enlargement of rat spinal cord; 191 neurons in 20 rats with an experimental peripheral neuropathy, and 104 in 10 sham-operated rats. Recordings were made 9-11 days after inducing the neuropathy by tying four loose ligatures around the sciatic nerve in the nerve-injured rats or performing a sham procedure in the sham-operated rats. 2. A survey of the general properties of all neurons encountered was made in the 10 sham-operated rats (104 neurons) and compared with those seen in 17 of the nerve-injured animals (180 neurons). The vast majority (87%; 156/180) of neurons recorded in the nerve-injured animals showed abnormal characteristics; these included responses to very gentle mechanical stimulation of the nerve-injury site and to manipulations that resulted in movement of this site such as extension of the leg and probing of the skin and muscle of the thigh (53%), absence of detectable peripheral receptive fields (RFs; 56%), and very high spontaneous activity (7%). In the sham-operated rats none of the neurons recorded could be activated by gentle mechanical stimulation of the sciatic nerve, and only 6% had no detectable peripheral RF. 3. In the nerve-injured animals, 31% (55/180) of cells had both a peripheral RF, and a response to gentle mechanical stimulation of the nerve-injury site. All cells of this type tested (n = 5) showed very prolonged responses (up to 10 min long) to 15 s pinch stimuli applied to the RF and to 15 s gentle tapping of the injury site. The majority of cells in this group were excited by noxious stimuli (71%; 39/55) and had C-fiber inputs (60%; 33/55). 4. The mean threshold temperatures for evoking responses to heat stimuli in cells tested in nerve-injured rats and in sham-operated animals were not different. However, there was a group of neurons in the nerve-injured rats that had low thresholds, failed to encode stimulus intensity, and did not have a C-fiber input. 5. There were significantly fewer neurons excited by low-intensity stimulation of the skin in the nerve-injured (24%; 43/180) than in the sham-operated rats (71%; 74/104). Measurements of mechanical threshold with von Frey hairs showed that, although the mean threshold did not change, none of the cells tested in the nerve-injured animals had thresholds < 12 mN, whereas the lowest threshold recorded in the sham-operated animals was 0.2 mN.(ABSTRACT TRUNCATED AT 400 WORDS)

Spatio-temporal interactions in cat retinal ganglion cells showing linear spatial summation.

Abstract: The spatio-temporal characteristics of cat retinal ganglion cells showing linear summation have been studied by measuring both magnitude and phase of the responses of these cells to drifting or sinusoidally contrast-modulated sinusoidal grating patterns. It has been demonstrated not only that X cells behave approximately linearly when responding with amplitudes of less than about 10 impulses/sec to stimuli of low contrast but also that cells of another type with larger receptive field centres (Q cells) behave approximately linearly under the same conditions. These Q cells appear to form a homogeneous group which is probably a subset of the tonic W cells (Stone & Fukuda, 1974) or sluggish centre-surround cells (Cleland & Levick, 1974). The over-all spatio-temporal frequency characteristics of cells showing linear spatial summation are not separable in space and time. The form of the spatial frequency responsivity function of these cells depends upon the temporal frequency at which it is measured while the temporal phase of their resonse measured at any constant temporal frequency depends upon the spatial frequency of the stimulus. The behaviour of X and Q cells is quite well explained by an extension of the model in which signals from centre and surround mechanisms with radially Gaussian weighting functions are summed to provide the drive to the retinal ganglion cell. While the general form of the temporal frequency response characteristics of these ganglion cells are probably provided by the characteristics of elements common to the centre and surround pathways, the spatio-temporal interactions can be explained by assuming that the surround signal is delayed relative to the centre signal by a few milliseconds.

Quantitative distribution of GABA-immunoreactive neurons in the visual cortex (area 17) of the cat.

Abstract: Cortical neurons using the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) are known to contribute to the formation of neuronal receptive field properties in the primary visual cortex (area 17) of the cat. In order to determine the cortical location of GABA containing neurons and what proportion of cortical neurons might use GABA as their transmitter, we analysed their distribution quantitatively using a post-embedding GABA immunohistochemical method on semithin sections in conjunction with stereological procedures. The mean total numerical density of neurons in the medial bank of the lateral gyrus (area 17) of five adult cats was 54,210±634 per mm3 (¯x±SD). An average of 20.60±0.48% (¯x±SEM) of the neurons were immunoreactive for GABA. The density of GABA-immunoreactive neurons was somewhat higher in layers II, III and upper VI, compared with layers I, IV, V and lower VI, with the lowest density being in layer V. The proportion of GABA-immunopositive cells relative to immunonegative neurons gradually decreased from the pia to the white matter. Layer I was different from other layers in that approximately 95% of its neurons were GABA-immunoreactive. The results allowed the calculation of the absolute numbers of GABAergic neurons in each layer under a given cortical surface area and could provide the basis for the quantitative treatment of cortical circuits.

Visual area of the lateral suprasylvian gyrus (Clare-Bishop area) of the cat.

Abstract: On anatomical and physiological grounds a zone of cat cortex deep in the medial bank of the suprasylvian sulcus (the Clare—Bishop area) is known to receive strong visual projections both from the lateral geniculate body and area 17. We have mapped receptive fields of single cells in this area in eight cats. Active responses to visual stimuli were found over most of the medial bank of the suprasylvian sulcus extending to the depths and over to the lowest part of the lateral bank. The area is clearly topographically arranged. The first responsive cells, recorded over the lateral convexity and 2-3 mm down the medial bank, had receptive fields in the far periphery of the contralateral visual fields. The receptive fields tended to be large, but showed considerable variation in size and scatter in their positions. As the electrode advanced down the bank, fields of successively recorded cells gradually tended to move inwards, so that in the depths of the sulcus the inner borders of many of the fields reached the vertical mid line. Here the fields were smaller, though they still varied very much in size. Receptive fields were larger than in 17, 18, or 19, but otherwise were not obviously different from the complex and lower-order hypercomplex fields in those areas. No simple fields, or concentric fields of the retino-geniculate type, were seen. Cells with common receptive-field orientation were grouped together, but whether or not the grouping occurs in columns was not established. Most cells were driven independently by the two eyes. Fields in the two eyes seemed to be identical in organization. Cells dominated by the contralateral eye were much more common than ipsilaterally dominated ones, but when cells with parafoveal and peripheral fields were considered separately, the asymmetry was seen to apply mainly to cells with peripheral fields.