Human receptive field characteristics: Probe analysis of stabilized images

The relationship between sighting dominance and the fading of a stabilized retinal image

“…The order of eye of stimulus. The absence of orientation-specific effects in our data contradicts the results of other studies of stabilized image fading (Brown et al, 1973;Cosgrove et al, 1972;Schmidt et al, 1972;Schmidt et al, 1971;Sharpe, 1972;Wade, 1972Wade, , 1973aWade, , 1973b. Generally, it has been reported that horizontal and vertical lines exhibit more perceptual stability as stabilized targets than do lines of oblique orientations.…”

“…For instance, suppose that stabilized images fade as a result of the occurrence of satiation and fatigue processes at various levels of the visual system. This presumably occurs due to the absence of transient stimulation usually provided by ocular tremor and eye movements that shift the stimulus action across many receptors in a temporal sequence (see Brown et al, 1973). At the cortical level, this could refer to differences in the distribution of cells responsive to the sighting and the nonsighting eyes, or to differences in their action.…”

“…Since afterimages often are considered to be equivalent to stabilized retinal projections, this result has potential theoretical importance. Stabilized retinal images have been used widely to study the involvement of basic neural mechanisms in human vision, especially the role of orientation and spatialfrequency-specific cortical units in contour perception (Brown, Schmidt, Fulgham, & Cosgrove, 1973;Cosgrove, Schmidt, Fulgham, & Brown, 1972;Schmidt, Fulgham, & Brown, 1971;Wade, 1972Wade, , 1973aWade, , 1973b. For this reason, the establishment of differences in the perception of stabilized retinal images in the dominant and the nondominant eyes could clarify the nature of the underlying neural substrate differences between the eyes.…”

Contrast-dependent interaction between steadily fixated lines

“…Insofar as steady fixation can be shown to reveal processes similar to those established for afterimages and optical stabilization, the method offers advantages over other procedures. In particular, with steady fixation, it is possible to manipulate the luminance of stimuli both within and between trials and thus to examine the dependence of stimulus visibility on characteristics whose control is impracticable with afterimages and confined to very few subjects with optical stabilization (e.g., Brown, Schmidt, Fulgham, & Cosgrove, 1973).…”