نتایج جستجو برای: spatial frequencies
تعداد نتایج: 450392 فیلتر نتایج به سال:
Lateralization touches virtually every function we think makes us human and interacts fundamentally with development. Here we connect lateralized function to anatomical asymmetries, and connect those anatomical asymmetries to temporal asymmetries in development. Our differential encoding (DE) model (Cipollini, Hsiao, & Cottrell, 2012; Hsiao, Cipollini, & Cottrell, 2013; Hsiao, Shahbazi, & Cottr...
To establish the mouse as a genetically tractable model for high-order visual processing, we characterized fine-scale retinotopic organization of visual cortex and determined functional specialization of layer 2/3 neuronal populations in seven retinotopically identified areas. Each area contains a distinct visuotopic representation and encodes a unique combination of spatiotemporal features. Ar...
Two sets of experiments were carried out to examine dependencies of two types of induced motion (motion assimilation and motion contrast) on spatial properties of stimuli in terms of spatial-frequency tuning of local motion detectors. In the first set, the magnitudes of motion assimilation and motion contrast for a sinusoidal grating were measured at a function of the spatial frequency of the i...
We examined the contribution of area 17 to visual function in two cats whose fixation was monitored by means of scleral search coils. Ibotenic acid lesions were made within the physiologically identified representation of the lower left visual field of area 17. In a detection task in which the cats simply indicated the presence or absence of a vertical grating, contrast sensitivity loss was gre...
Vuilleumier, Armony, Driver & Dolan (2003) have shown that amygdala cells to fearful expressions of human faces seem to be more activated by intact or low spatial frequency (LSF) faces than high spatial frequency (HSF) faces. These fMRI results may suggest that LSF components might be processed by a subcortical pathway that is assumed to bypass the striate cortex in order to process LSF compone...
Humans extract visual information from the world through spatial frequency (SF) channels that are sensitive to different scales of light-dark fluctuations across visual space. Using two methods, we measured human SF tuning for discriminating videos of human actions (walking, running, skipping and jumping). The first, more traditional, approach measured signal-to-noise ratio (s/n) thresholds for...
In three experiments we measured reaction times (RTs) and error rates in identifying the global structure of spatially filtered stimuli whose spatial-frequency content was selected by means of three types of 2-D isotropic filters (Butterworth of order 2, Butterworth of order 10, and a filters with total or partial Gaussian spectral profile). In each experiment, low-pass (LP), bandpass (BP), and...
Visually evoked responses to counterphased gratings were recorded from the cat visual cortex before and after physostigmine administration. Physostigmine markedly reduced the responses to low spatial frequencies, but minimally affected the response to high frequencies. This effect is considered cholinergic since it could be reversed by atropine. These results support at least a two-channel mode...
Spatiotemporal frequency responses were measured at different levels of light adaptation for cat X and Y retinal ganglion cells. Stationary sinusoidal luminance gratings whose contrast was modulated sinusoidally in time or drifting gratings were used as stimuli. Under photopic illumination, when the spatial frequency was held constant at or above its optimum value, an X cell's responsivity was ...
A laboratory prototype spectral-spatial interferometer has been constructed to demonstrate the feasibility of the double-Fourier technique at far infrared (FIR) wavelengths (0.15-1 THz). It is planned to use this demonstrator to investigate and validate important design features and data-processing methods for future astronomical FIR interferometer instruments. In building this prototype, we ha...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید