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Visual receptive fields in the superficial hamster SC do not vary substantially in RF size with RF eccentricity.

Visual receptive field sizes change in the deep SC with eccentricity, they do not in the superficial hamster SC.

Spatial attention does not seem to affect the selectivity of visual neurons—just the vigour of their response.

Wickelgren found the receptive fields of audio-visual neurons in the deep SC to have no sharp boundaries.

Mysore and Knudsen say that deep SC neurons respond to relative saliency of a stimulus, i.e. to the saliency of stimuli in their receptive fields compared to the saliency of stimuli outside their receptive fields.

Visuo-somatosensory neurons in the putamen with somatosensory RFs in the face are very selective: They seem to respond to visual stimuli consistent with an upcoming somatosensory stimulus (close-by objects approaching to the somatosensory RFs of the neurons).

Graziano and Gross report on visuo-somatosensory cells in the putamen in which remapping seems to be happening: Those cells responded to visual stimuli only when the animal could see the arm in which the somatosensory RF of those cells was located.

Multisensory AES cell receptive fields are not well-delineated regions in space in which and only in which a stimulus evokes a stereotyped response. Instead, they can have a region, or multiple regions, where they respond vigorously and others, surrounding those `hot spots', which in which the response is less strong.

AES neurons show an interesting form of the principle of inverse effectiveness: Cross-sensory in regions in which the unisensory component stimuli would evoke only a moderate response produce additive (or, superadditive?) responses. In contrast, Cross-sensory stimuli at the `hot spots' of a neuron tend to produce sub-additive responses.

In some SC neurons, receptive fields are not in spatial register across modalities.

Receptive fields of SC neurons in different modalities tend to overlap.

Multisensory SC cell receptive fields are not well-delineated regions in space in which and only in which a stimulus evokes a stereotyped response. Instead, they can have a region, or multiple regions, where they respond vigorously and others, surrounding those `hot spots', which in which the response is less strong.

Receptive fields in AEV tend to be smaller for cells with RF centers at the center of the visual field than for those with RF centers in the periphery.

RFs in AEV are relatively large.

Rearing barn owls in darkness results in mis-alignment of auditory and visual receptive fields in the owls' optic tectum.

Rearing barn owls in darkness results in discontinuities in the map of auditory space of the owls' optic tectum.

Middlebrooks and Knudsen report on sharply delineated auditory receptive fields in some neurons in the deep cat SC, in which there is an optimal region from which stimuli elicit a stronger response than in other places in the RF.

A minority of deep SC neurons are omnidirectional, responding to sounds anywhere, albeit with a defined best area.

There is considerable variability in the sharpness of spatial tuning in the responses to auditory stimuli of deep SC neurons.

Middlebrooks and Knudsen define a spatial receptive field of a neuron as that angular range from which a stimulus elicits any response above baseline.

The best area, on the other hand, is that range from which it a stimulus elicits at least 75% of the maximum response.

Middlebrooks and Knudsen note that other studies use different definitions.

Auditory receptive fields tend to be greater and contain visual receptive fields in the deep SC of the owl.

According to Wilson and Bednar, wire-length optimization presupposes that neurons need input from other neurons with similar feature selectivity. Under that assumption, wire length is minimized if neurons with similar selectivities are close to each other. Thus, the kind of continuous topological feature maps we see optimize wire length.

The idea that neurons should especially require input from other neurons with similar spatial receptive fields is unproblematic. However, Wilson and Bednar argue that it is unclear why neurons should especially require input from neurons with similar non-spatial feature preferences (like orientation, spatial frequency, smell, etc.).

In the development of SC neurons, receptive fields are initially very large and shrink with experience.

Visual receptive fields in the deeper SC are larger than in the superficial SC.

The parts of the sensory map in the deeper SC corresponding to peripheral visual space have better representation than in the visual superficial SC.

Do the parts of the sensory map in the deeper SC corresponding to peripheral visual space have better representation than in the visual superficial SC because they integrate more information; does auditory or tactile localization play a more important part in multisensory localization there?

Moving the eyes shifts the auditory and somatosensory maps in the SC.

Visual receptive fields in the superficial monkey SC do vary substantially in RF size with RF eccentricity.

In some animals, receptive field sizes do and in some they don't change substantially with RF excentricity.

The neurons in the superficial (rhesus) monkey SC do not exhibit strong selectivity for specific shapes, stimulus orientation, or moving directions. Some of them do show selectivity to stimuli of specific sizes.

The activity profiles for stimuli moving through superficial SC neuron RFs shown in Cynader and Berman's work look similar to Poisson-noisy Gaussians, however, the authors state that the strength of a response to a stimulus was the same regardless where in the activating region it was shown.

The neurons in the superficial (rhesus) monkey SC largely prefer moving stimuli over non-moving stimuli.

In the study due to Xu et al., multi-sensory enhancement in specially-raised cats decreased gradually with distance between uni-sensory stimuli instead of occurring if and only if stimuli were present in their RFs. This is different from cats that are raised normally in which enhancement occurs regardless of stimulus distance if both uni-sensory components both are within their RF.

Visual receptive fields in the sc usually consist of an excitatory central region and an inhibitory surround.

(Auditory receptive fields also often seem to show this antagonism.)

Moving eyes, ears, or body changes the receptive field (in external space) in SC neurons wrt. stimuli in the respective modality.

Receptive fields in the dorsal pathway of visual processing are less retinotopic and more head-centered.

Parvocellular ganglion cells are color sensitive, have small receptive fields and are focused on foveal vision.

Magnocellular ganglion cells have lower spatial and higher temporal resolution than parvocellular cells.

Certain receptive fields in the cat striate cortex can be modeled reasonably well using linear filters, more specifically Gabor filters.

The receptive field properties of neurons in the cat striate cortex have been modeled as linear filters. In particular three types of linear filters have been proposed:

  • Gabor filters,
  • filters that based on second differentials of Gaussians functions,
  • difference of Gaussians filters.

Difference-of-Gaussians filters are parsimonious candidates for modeling the receptive fields of striate cortex cells, because the kind of differences of Gaussians used in striate cortex (differences of Gaussians with different peak locations) can themselves be computed linearly from differences of Gaussians which model receptive fields of LGN cells (where the peaks coincide), which provide the input to the striate cortex.

Both simple and complex cells' receptive fields can be described using difference-of-Gaussians filters.

Cuppini et al. expand on their earlier work in modeling cortico-tectal multi-sensory integration.

They present a model which shows how receptive fields and multi-sensory integration can arise through experience.

Ganglion cells in the retina connect the brain to a small, localized number of photoreceptors. The small population—or the region in space from which it receives incoming light— are called a ganglion cell's receptive field. They respond best either to patterns of high luminance in the center of that small population and low luminance at its periphery, or to the opposite pattern. Ganglion cells with the former characteristics are called "on-center" cells, the others "off-center" cells.

Simple center-surround receptive fields are selective of specific spatial frequencies. Other filters, like Gabor filters or linear combinations of simple center-surround receptive fields, can be selective for

Magnocellular ganglion cells have large receptive fields.