Backward and forward masking associated with saccadic eye movement

Abstract

Visual masking effects on test flash thresholds were measured under real and simulated eye movement conditions to determine whether visual masking is primarily responsible for elevations in threshold that are sometimes associated with saccadic eye movements. Brief luminous flashes presented to the central retina before, during, and after saccades were masked by stimuli presented either pre-or postsaccadically. The amount and time course of masking were quantitatively dependent on stimulus parameters of intensity and temporal separation and were unaffected by eye movement parameters (amplitude, velocity, direction) as long as retinal stimulus conditions were constant. The duration of forward masking was longer than that of backward masking. When retinal conditions during saccades were mimicked while the eyes were held steady, masking interactions were identical to those obtained during real saccades. These results indicate that masking effects during saccades in ordinary environments are determined solely by the stimulus situation at the retina. Putative nonvisual, centrally originating saccadic suppression suggested by other authors is evidently not additive with visually determined masking during saccades.

Transsaccadic processing: stability, integration, and the potential role of remapping

“…When the light remained on for a sufficient period after refixation, however, backward masking eliminated any percept of the saccadic blur, so that only the crisp, postsaccadic image of the vertical bar could be perceived. In subsequent experiments, Campbell and Wurtz (1978) and Brooks, Impelman, and Lum (1981) obtained consistent findings and also found that forward masking from the presaccadic image contributes to suppression.…”

Intra-saccadic motion streaks as cues to linking object locations across saccades

“…Although temporal masking is often attributed to stimuli covering the entire display (Castet et al, 2002) or even the entire visual field (Campbell & Wurtz, 1978), it is possible to achieve similar effects with just simple flashes of light without a necessary spatial or retinal overlap, an effect attributed to meta-contrast masking (Matin et al, 1972). Interestingly, this mechanism has been shown to be equally effective both during real and simulated saccades (Brooks et al, 1980;Brooks et al, 1981). The absence of post-saccadic masking, however, is not representative for the circumstances of natural vision, where every intra-saccadic input is followed (and thus masked) by a more reliable and stable retinal image (Castet, 2010).…”

“…Perception of intra-saccadic motion streaks induced by saccades across a static stimulus (often presented in a dimly lit, uniform background or in complete darkness) has been investigated in past studies. For example, Matin et al (1972) investigated the perceived length of motion streaks induced by varying on-durations of a single light source, and Brooks et al (1981) studied the threshold elevation in detecting them independent of pre-and post-saccadic masks during both real and simulated saccades. Bedell and Yang (2001) used a similar paradigm and found that, given similar prolonged post-movement durations of the light source being on, perceived streaks were still significantly longer during fixation than during saccades, suggesting an additional attenuation of smear around saccades.…”

Perceptual saccadic suppression starts in the retina

“…On the other hand, perceptual saccadic suppression could also arise as a result of the visual consequences of retinal image shifts 2,[19][20][21][22][23][24][25][26][27][28][29][30] . After all, the early visual system, including the retina, is a highly sensitive light sensing device, and can capture visual transients associated with saccade-induced retinal image shifts.…”