Inaccurate Space Perception Seeing Through Fences.

According to the sequential surface integration process hypothesis, the fine near-ground-surface representation and the homogeneous ground surface play a vital role in the representation of the ground surface. When an occluding box or opaque wall is placed between observers and targets, observers underestimate egocentric distance. However, in our daily life, many obstacles are perforated and cover the ground surface and targets simultaneously (e.g., fences). Humans see and observe through fences. The images of these fences and targets, projected onto observers' retinas, overlap each other. This study aims to explore the effects of perforated obstacles (i.e., fences) on space perception. The results showed that observers underestimated the egocentric distances when there was a fence on the ground surface relative to the no-fence condition, and the effect of widely spaced thick wood fences was larger than that of narrowly spaced thin iron fences. We further demonstrated that this effect was quite robust when the target size had a visual angle of 1°, 2°, or 4° in three virtual reality experiments. This study may add support for the notion that the sequential surface integration process hypothesis is applicable even if the obstacle is perforated and covers the target.

No effect of autistic traits on social attention: evidence based on single-cue and conflicting-cues scenarios.

Individuals often use others' gaze and head directions to direct their attention. To investigate the influence of autistic traits on social attention, we conducted two experiments comparing groups with high and low autistic traits in single-cue (Experiment 1) and conflicting-cue (Experiment 2) scenarios. Our findings indicate that individuals responded more rapidly to the direction of a single social cue or the consensus of multiple cues. However, we did not observe significant differences in social attention between individuals with high and low autistic traits. Notably, as the stimulus onset asynchrony (SOA) increased, individuals with low autistic traits exhibited greater improvements in reaction speed compared to those with high autistic traits. This suggests that individuals with low autistic traits excel at leveraging temporal information to optimize their behavioral readiness over time, hinting at potential variations in cognitive flexibility related to autistic traits.

The mechanism for the specificity of gaze direction: Inhibiting background location.

The experiment combined the spatial Stroop paradigm to examine the effect of background location on the perception of arrow or gaze direction in the vertical dimension by manipulating the congruence between the target direction and background location, and to validate a possible cognitive mechanism for gaze direction specificity - inhibiting background location. The results showed that when subjects were required to identify the target direction in a Stroop task (Experiment 1), the gaze cue failed to induce the Stroop effect. However, when subjects were required to judge the congruence between the target direction and the background location (Experiment 2), the gaze cue and the arrow cue both induced the Stroop effect. This suggests that " inhibiting background location" is responsible for the elimination of the spatial Stroop effect by gaze direction, which may one of the mechanisms for gaze direction specificity.

The celebrity effect on gaze following in older and young adults.

BACKGROUND: In daily life, people often follow others' gaze direction to infer their attention and mental state. This phenomenon is known as gaze following. OBJECTIVE: This study aimed to explore whether gaze following in different age groups is influenced by celebrity identity. METHODS: We recruited 70 participants, including 35 older adults and 35 young adults. The experimental materials consisted of three faces with different identity information (a political leader, a movie star, and an ordinary person). Each face had left and right gaze conditions. Targets and cues were presented with both longer and shorter stimulus onset asynchrony (SOA) conditions. RESULTS: Both older adults and young adults exhibited similar gaze following behaviors. Importantly, the celebrity effect on gaze following was observed in both groups, with stronger effects induced by the leader's and star's gazes compared to the ordinary person's gaze. Older adults showed a larger facilitation effect under the longer SOA condition compared to the shorter SOA, while no such SOA-related facilitation effect was found for young adults. CONCLUSION: These findings suggest that older adults can integrate social information from others' faces (celebrity identity) into the process of gaze following as effectively as young adults.

The allocentric nature of ground-surface representation: A study of depth and location perception.

When observers perceive 3D relations, they represent depth and spatial locations with the ground as a reference. This frame of reference could be egocentric, that is, moving with the observer, or allocentric, that is, remaining stationary and independent of the moving observer. We tested whether the representation of relative depth and of spatial location took an egocentric or allocentric frame of reference in three experiments, using a blind walking task. In Experiments 1 and 2, participants either observed a target in depth, and then straightaway blind walked for the previously seen distance between the target and the self; or walked to the side or along an oblique path for 3 m and then started blind walking for the previously seen distance. The difference between the conditions was whether blind walking started from the observation point. Results showed that blind walking distance varied with the starting locations. Thus, the represented distance did not seem to go through spatial updating with the moving observer and the frame of reference was likely allocentric. In Experiment 3, participants observed a target in space, then immediately blind walked to the target, or blind walked to another starting point and then blind walked to the target. Results showed that the end location of blind walking was different for different starting points, which suggested the representation of spatial location is likely to take an allocentric frame of reference. Taken together, these experiments convergingly suggested that observers used an allocentric frame of reference to construct their mental space representation.

Methods for measuring egocentric distance perception in visual modality.

Egocentric distance perception has been widely concerned by researchers in the field of spatial perception due to its significance in daily life. The frame of perception involves the perceived distance from an observer to an object. Over the years, researchers have been searching for an optimal way to measure the perceived distance and their contribution constitutes a critical aspect of the field. This paper summarizes the methodological findings and divides the measurement methods for egocentric distance perception into three categories according to the behavior types. The first is Perceptional Method, including successive equal-appearing intervals of distance judgment measurement, verbal report, and perceptual distance matching task. The second is Directed Action Method, including blind walking, blind-walking gesturing, blindfolded throwing, and blind rope pulling. The last one is Indirect Action Method, including triangulation-by-pointing and triangulation-by-walking. In the meantime, we summarize each method's procedure, core logic, scope of application, advantages, and disadvantages. In the end, we discuss the future concerns of egocentric distance perception.

Egocentric Distance Perception Disorder in Amblyopia.

Egocentric distance perception is a psychological process in which observers use various depth cues to estimate the distance between a target and themselves. The impairment of basic visual function and treatment of amblyopia have been well documented. However, the disorder of egocentric distance perception of amblyopes is poorly understood. In this review, we describe the cognitive mechanism of egocentric distance perception, and then, we focus on empirical evidence for disorders in egocentric distance perception for amblyopes in the whole visual space. In the personal space (within 2 m), it is difficult for amblyopes to show normal hand-eye coordination; in the action space (within 2 m~30 m), amblyopes cannot accurately judge the distance of a target suspended in the air. Few studies have focused on the performance of amblyopes in the vista space (more than 30 m). Finally, five critical topics for future research are discussed: 1) it is necessary to systematically explore the mechanism of egocentric distance perception in all three spaces; 2) the laws of egocentric distance perception in moving objects for amblyopes should be explored; and 3) the comparison of three subtypes of amblyopia is still insufficient; 4) study the perception of distance under another theoretical framework; 5) explore the mechanisms of amblyopia by Virtual Reality.

The foggy effect of egocentric distance in a nonverbal paradigm.

Inaccurate egocentric distance and speed perception are two main explanations for the high accident rate associated with driving in foggy weather. The effect of foggy weather on speed has been well studied. However, its effect on egocentric distance perception is poorly understood. The paradigm for measuring perceived egocentric distance in previous studies was verbal estimation instead of a nonverbal paradigm. In the current research, a nonverbal paradigm, the visual matching task, was used. Our results from the nonverbal task revealed a robust foggy effect on egocentric distance. Observers overestimated the egocentric distance in foggy weather compared to in clear weather. The higher the concentration of fog, the more serious the overestimation. This effect of fog on egocentric distance was not limited to a certain distance range but was maintained in action space and vista space. Our findings confirm the foggy effect with a nonverbal paradigm and reveal that people may perceive egocentric distance more "accurately" in foggy weather than when it is measured with a verbal estimation task.

Cortical Distance but Not Physical Distance Modulates Attentional Rhythms.

It has been well documented that the spotlight of attention is intrinsically rhythmic and oscillates by discretely sampling either single or multiple objects. However, the neural site of attentional rhythms remains poorly understood. Considering the topography of visual cortical areas, we modulated the cortical distances of two gratings while fixing the corresponding retinal distance by setting the gratings on different sides (cortically far, Experiment 1) or on the same side (cortically near, Experiment 2) of the vertical median, to investigate the interhemispheric divide effect in attentional rhythms. The cue-target stimulus onset asynchrony (SOA) varied from 0.1 s to 1.08 s in 20-ms increments, allowing fluctuations below 50 Hz to be examined. The results showed that when the two stimuli were on opposite sides of the vertical meridian, attentional rhythms were observed at theta and alpha frequencies, consistent with the results reported in previous studies. However, when the two stimuli were located on the same side of the vertical meridian, attentional rhythms were not observed. This study indicates that attentional rhythms are modulated by cortical distance but not by physical distance.

Behavioral Oscillations in Visual Attention Modulated by Task Difficulty.

The spotlight of attention is full of discrete moments and operates periodically. Recently, it has been well-documented there were behavioral oscillations in visual attention, however, different periodicities were demonstrated. Task difficulty may be an important factor causing disagreement in attentional periodic patterns. The present study examined behavioral oscillations in visual attention during difficult and easy tasks. A modified high temporal resolution cue-target paradigm in which the cue-target stimulus onset asynchrony (SOAs) varied from 0.1 to 1.08 s in steps of 20 ms was used. The target was detected with the accuracy of 65% in the difficult condition and 75% in the easy condition. Oscillatory patterns were analyzed and observed in behavioral performance. A theta rhythm was visible in the difficult version. However, attention oscillation increased to a higher frequency in the easy version. Task difficulty was negatively related to power for all bands. Our findings suggest that the attention spotlight switched faster when the task was easy, while, it switched much more slowly when the task was difficult in order to obtain more information. A flexible mechanism for attention spotlight was demonstrated, and task demand modulated attention oscillations.