A form of repetition blindness in visually unimpaired individuals was found for objects presented during saccades. Observers were asked to draw their percepts after making saccades across an LED strip that “painted” an image on their retinas by presenting sequential columns of a bitmap at a speed to match a 30-degree saccade. During experimental trials, repetitions of a single letter (either “A,” “X,” “H,” or “V”) were presented across saccades. Although an average of six letters were presented across each saccade, observers typically indicated perceiving only a single instance of the letter in their drawings. This inability to perceive multiple instances of a letter was not due to a limited region of attentional processing, as it only attained for multiple instances along the axis of the saccade—horizontal saccades did not affect perception of multiple letters along the vertical axis. This effect is likely due to selective suppression of visual areas during saccades.

Visual perception during rapid saccadic eye movements is typically suppressed. However, in the phenomenon of Saccadic Persistence of Vision (SPoV; Nelson et al., 2020), this suppression can be significantly attenuated. In the current study, we investigate the effectiveness of horizontal vs. vertical and oblique saccades for detecting the image presented during SPoV. Participants viewed a rapidly flashing LED strip during 20 degree saccades, which "painted" an image across their retina. Results indicate a higher degree of accuracy during horizontal saccades than during vertical or oblique saccades.

A form of simultanagnosia in visually unimpaired individuals was found for objects presented during saccades. 18 college-age observers were asked to draw their percepts after making saccades across an LED strip that “painted” an image on their retinas by presenting sequential columns of a bitmap at a speed to match a 30 degree saccade. During experimental trials, repetitions of a single letter (either “A”, “X”, “H”, or “V”) were presented across saccades. Although an average of six letters were presented across each saccade, observers nearly always indicated perceiving only a single instance of the letter in their drawings. This inability to perceive multiple instances of a letter was not due to a limited region of attentional processing, as it only attained for multiple instances along the axis of the saccade -- horizontal saccades did not affect perception of multiple letters along the vertical axis. This effect is likely due to known mechanisms of suppression of visual areas during saccades, particularly the medial temporal and inferior pulvinar regions (Berman et al., 2017).

In 1923, Adhemar Gelb and Ragnar Granit, two prominent researchers in early Gestalt perceptual theory, reported a lower threshold for detection of a target (a small colored dot) on the ground region of an image than on an adjacent figural region. Although their results had a wide influence on the understanding of figure-ground perception, they are at odds with more recent investigations in which figural regions appear to have a processing advantage over ground regions. The two present studies replicated Gelb and Granit's experiment using a similar figure-ground stimulus albeit with a two-alternative forced choice procedure rather than their original method of adjustment. Experiment 1 found that, contrary to Gelb and Granit's findings, a detection advantage was found for the figural over the ground region. Experiment 2 indicated that explicit contours might have played a role in detection.

In 1923, Gelb and Granit, using a method of adjustment for a small red light, reported a lower threshold for the target when presented on a ground region than on an adjacent figural region. More recent work in perceptual organization has found precisely the opposite-a processing advantage seems to go to items presented on the figure, not the ground. Although Gelb and Granit continue to be cited for their finding, it has not previously been available as an English translation. Understanding their methodology and results is important for integrating early Gestalt theory with more recent investigations.

We investigated how color preferences vary according to season and whether those changes could be explained by the ecological valence theory (EVT). To do so, we assessed the same participants' preferences for the same colors during fall, winter, spring, and summer in the northeastern United States, where there are large seasonal changes in environmental colors. Seasonal differences were most pronounced between fall and the other three seasons. Participants liked fall-associated dark-warm colors-for example, dark-red, dark-orange (brown), dark-yellow (olive), and dark-chartreuse-more during fall than other seasons. The EVT could explain these changes with a modified version of Palmer and Schloss' (2010) weighted affective valence estimate (WAVE) procedure that added an activation term to the WAVE equation. The results indicate that color preferences change according to season, as color-associated objects become more/less activated in the observer. These seasonal changes in color preferences could not be characterized by overall shifts in weights along cone-contrast axes.

The relation between figure ground organization and attention is a complicated one. Some findings (Nelson & Palmer, 2008; Wong & Weisstein, 1982) have indicated an advantage for the figural region. However, in a much earlier work, Gelb & Granit (1923) presented evidence that targets in the ground region were more perceptually distinguishable than targets in the figure region, a claim that would seem to be contrary. In the present research, we re-examine Gelb & Granit’s work, and claim that these effects are due to a lower-level effect, that of masking due to proximity to surrounding contours. In a series of experiments using stimuli constructed from the original studies, using a 2AFC detection procedure, we find that targets are more detectible in the ground region only when the figure is surrounded by fully articulated contours. Meeting abstract presented at VSS 2015

The 44-minute documentary Where Am I, part of ‘The Nature of Things’ Series by Bullfrog Films, blazes through a number of findings on spatial cognition from various researchers around the world. So...

Background A variety of studies have demonstrated gains in cognitive ability following cognitive training interventions. However, other studies have not shown such gains, and questions remain regarding the efficacy of specific cognitive training interventions. Cognitive training research often involves programs made up of just one or a few exercises, targeting limited and specific cognitive endpoints. In addition, cognitive training studies typically involve small samples that may be insufficient for reliable measurement of change. Other studies have utilized training periods that were too short to generate reliable gains in cognitive performance. Methods The present study evaluated an online cognitive training program comprised of 49 exercises targeting a variety of cognitive capacities. The cognitive training program was compared to an active control condition in which participants completed crossword puzzles. All participants were recruited, trained, and tested online (N = 4,715 fully evaluable participants). Participants in both groups were instructed to complete one approximately 15-minute session at least 5 days per week for 10 weeks. Results Participants randomly assigned to the treatment group improved significantly more on the primary outcome measure, an aggregate measure of neuropsychological performance, than did the active control group (Cohen’s d effect size = 0.255; 95% confidence interval = [0.198, 0.312]). Treatment participants showed greater improvements than controls on speed of processing, short-term memory, working memory, problem solving, and fluid reasoning assessments. Participants in the treatment group also showed greater improvements on self-reported measures of cognitive functioning, particularly on those items related to concentration compared to the control group (Cohen’s d = 0.249; 95% confidence interval = [0.191, 0.306]). Conclusion Taken together, these results indicate that a varied training program composed of a number of tasks targeted to different cognitive functions can show transfer to a wide range of untrained measures of cognitive performance. Trial Registration ClinicalTrials.gov NCT-02367898

In typical figure–ground displays the figure has shape and is perceived as being in front, whereas the ground is shapeless and recedes to the back. The recent literature on the visual perception of holes has questioned the nature of this coupling between shape and depth both theoretically and empirically. In this paper we provide a theoretical framework that clarifies the underlying issues and we report new evidence supporting the view that the shape of a hole is perceived as the shape of its interior region. Palmer, Davis, Nelson, and Rock (2008 Perception, 37, 1569–1586) showed that the shape of the interior region of a hole is remembered as such, even though the surface visible through it is perceived as farther in depth. The present paper extends this evidence to perceiving holes. Participants performed a speeded shape-matching task in which they compared a surrounded interior region (of either a hole or an object) or its exterior complement with one of several shapes. The results indicate that holes are perceived as shaped in the same way as their material counterparts. We conclude that the shape of a hole is encoded as the shape of its interior region, even though that region contains no surface material. These results can be reconciled with recent experiments that have provided evidence that holes are perceived differently from their material counterparts.

According to Palmer and Schloss’s (2010) ecological theory of color aesthetics, people’s preferences for colored objects influence their preferences for the colors associated with those objects. If so, broad changes in environmental colors (and any learned associations with them) might affect color preferences. The current study examined color preferences over the four seasons of the year at a college in New England, where there is substantial seasonal variation in the color of the outdoor environment. Thirty-nine participants who had lived in the area for at least six years rated their preferences on the 37 colors of the Berkeley Color Project, including eight chromatic hues at four "cuts" in color space (light, dark, saturated, and muted), and five achromatic colors (white, black, and three shades of gray), during the fall, winter, spring, and summer seasons. Seasonal changes in color preference were evident, particularly between ratings done in the spring and fall for colors characteristically associated with these seasons. Participants preferred dark warm colors more in the fall and light colors more in the spring. Substantial gender differences in color preference were also evident, with seasonal differences being more pronounced in males than females. These results are compared with recent theories and data about color preferences (e.g., Hurlbert & Ling, 2007; Schloss & Palmer, 2011). Meeting abstract presented at VSS 2012

A surrounded region perceived as a hole presents an interesting case for figure-ground perception. Previous experiments have demonstrated that the shapes of holes are remembered nearly as well as objects (Palmer, Davis, Nelson, & Rock, 2008), although according to classic figure-ground theories, the region in front should receive a shape description. Others have suggested that holes would not receive a shape description in a speeded perceptual task (Bertamini, 2006). To address this possibility, in the current experiment participants made a speeded perceptual judgment (4AFC) about the matching shape for either a hole or an object, and when they were given either the surrounded shape or its complement. Results clearly show that, contrary to predictions that the shape of the front region should always be perceived, participants were faster when matching the shape of the hole than in matching the shape of its complement (that is, the edge belonging to the surrounding region that was in front). These results are discussed in terms of a functional visuomotor theory of why the shape of holes might be perceived.

What characterizes the processing difference between regions that are segregated into figure and ground? Only one of the adjacent regions “owns” the contour, and that region (the figure) is seen to be in front, while the ground continues amodally behind. Here it is proposed that the same Gestalt cues that that bias figure/ground segregation (such as surroundedness, meaningfulness, and convexity) also act to spread attention to the figural side of the contour. The present experiments demonstrate that processing in the figural region is enhanced, which indicates a preferential allocation of attentional resources. The general method used was a presentation of a two adjacent regions, followed by a variable SOA to a target in one of the regions. It was found that in both reaction time and discrimination measures, processing was improved on the region biased to be perceived as figure over the region biased to be perceived as ground. Factors tested to date include surroundedness and meaningfulness.

Some perceptual theories of autism have postulated that autistics (and others along the spectrum) may process visual information at an “earlier” level. For example, hierarchical stimuli may be processed at a more local level, and there may be less susceptibility to visual illusions of size and shape that rely on contextual information. The current experiments tested perceptual grouping in autistics and those with Asperger's Syndrome, setting up a 2AFC procedure where one choice corresponded to grouping at an “early” or more retinal level, and the other choice corresponded to grouping at a “later” level, after such processes as amodal completion and illusory contour formation. Results did not support a difference in processing styles between adolescents on the autistic spectrum and controls, suggesting that if there is a difference in perceptual organization, it is subtle.

Holes present an intriguing paradox for figure-ground organization. Although the outside of a hole is seen as the closer figure and the inside as the farther ground, the shape of the interior region appears to be well perceived and remembered, contrary to the usual claim that border assignment is unidirectional and linked for depth and shape. Recent evidence has questioned the claim that the interior shapes of holes are perceived (e.g., Bertamini & Croucher, 2003). We present four experiments that demonstrate circumstances under which the shapes of visual holes are perceived and remembered — or not. In Experiment 1, subjects saw a series of novel shapes presented as real, physical models of 2D surfaces with and without holes. A later shape recognition test showed that they remembered the interior shapes of the holes as well as the shapes of the solid objects. A second study with stereoscopically viewed depth displays demonstrated that memory for the interior shape of holes is limited to intrinsic holes, whose contours are continuous in depth within a single object. Memory for accidental visual holes, arising from the coincidental alignment of discontinuous contours of two or more objects separated in depth, was no better than chance. A control experiment ruled out explanations based on artifacts due to differential size or shape. Further studies used instructional manipulations to investigate the influence of differential attention to intrinsic versus accidental holes to determine whether the observed differences in shape memory are obligatory or strategic. The findings are discussed as supporting an account of hole perception in which the shape of a hole is attended and encoded as an immaterial (or virtual) surface where matter is missing from the otherwise solid surface, perhaps with a “missing sign” (analogous to a minus sign in mathematics) to represent its status as a hole rather than as a material part.

To understand the way in which video-game play affects subsequent perception and cognitive strategy, two experiments were performed in which participants played either a fast-action game or a puzzle-solving game. Before and after video-game play, participants performed a task in which both speed and accuracy were emphasized. In experiment 1 participants engaged in a location task in which they clicked a mouse on the spot where a target had appeared, and in experiment 2 they were asked to judge which of four shapes was most similar to a target shape. In both experiments, participants were much faster but less accurate after playing the action game, while they were slower but more accurate after playing the puzzle game. Results are discussed in terms of a taxonomy of video games by their cognitive and perceptual demands.