The geometry of consciousness.

Conscious experience implies a reference-frame or vantage, which is often important in scientific models. Control models of ball-interception are used as an example. Models that use viewer-dependent egocentric reference-frames are contrasted with viewer-independent allocentric ones. Allocentric reference-frames serve well for models like Newtonian physics, which utilize static coordinate-systems that allow forces and object-movements to be compartmentalized. In contrast, egocentric reference-frames are natural for modeling mobile organisms or robots when controlling perception-action behavior. Lower-level perception-action behavior is often characterized using egocentric coordinate-systems that optimize processing-speed, while higher-level cognitive-processes use allocentric frames that provide a stationary spatial reference. Brain-behavior models like the Ventral-Stream What System, and Dorsal-Stream Where-How System, also respectively utilize allocentric and egocentric reference-frames. Reference-frame clarification can resolve disputes about models of control-tasks like running to catch baseballs, and can provide insights for biomimetic-robots. Confusion regarding geometry and reference-frames contributes to a lack of clarity between how and when egocentric versus allocentric geometries are imposed, with perception-actions generally being more egocentric and conscious experience more allocentric.

Optical angular constancy is maintained as a navigational control strategy when pursuing robots moving along complex pathways.

The optical navigational control strategy used to intercept moving targets was explored using a real-world object that travels along complex, evasive pathways. Fielders ran across a gymnasium attempting to catch a moving robot that varied in speed and direction, while ongoing position was measured using an infrared motion-capture system. Fielder running paths were compared with the predictions of three lateral control models, each based on maintaining a particular optical angle relative to the robotic target: (a) constant alignment angle (CAA), (b) constant eccentricity angle (CEA), and (c) linear optical trajectory (LOT). Findings reveal that running pathways were most consistent with maintenance of LOT and least consistent with CEA. This supports that fielders use the same optical control strategy of maintaining angular constancy using a LOT when navigating toward targets moving along complex pathways as when intercepting simple ballistic trajectories. In those cases in which a target dramatically deviates from its optical path, fielders appear to simply reset LOT parameters using a new constant angle value. Maintenance of such optical angular constancy has now been shown to work well with ballistic, complex, and evasive moving targets, confirming the LOT strategy as a robust, general-purpose optical control mechanism for navigating to intercept catchable targets, both airborne and ground based.

Absence of lateral navigational bias in young children.

Previous research has shown American adults exhibit a systematic navigational bias to favor moving to the right when locomoting around obstacles and other people. To further investigate how and when the right-side navigational bias develops, the authors tested pre-school and early elementary school aged American children. Children ran down a straight pathway with an object at the center of the end-line. Unlike replicated findings with adults, both pre-school and early elementary school aged children showed no tendency to favor either side of the object. These findings support that the rightward navigation bias found in adults is not present in children up to elementary school, and suggest that the onset of bias occurs during the age range of late elementary or secondary school.

Vertical attention bias for tops of objects and bottoms of scenes.

Past research demonstrated a top-salience bias in object identification, with random shapes appearing more similar when they share the same top versus the same bottom. This is consistent with tops of natural objects and lifeforms tending to be more informative locations of intentionality and functionality, leading observers to favor attending to tops. However, this bias may also reflect a generic downward vantage tendency that occurs with more informative interactive aspects of scenes typically lying below the horizon. Two experiments test for this overall pattern of vertical attention bias (VAB) for both objects and scenes. Participants observed picture triptychs and judged if the center object or scene appeared more similar to flanking comparison figures that contain the same top versus same bottom. Experiment 1 used vertically information-balanced impoverished stimuli, either polygon objects or polygon-array scenes. Experiment 2 extended the triptych stimuli to naturalistic objects or scenes. Results generally support a VAB for object tops and scene bottoms that varies as a function of the informative aspects of visually attended stimuli. This pattern held for information-balanced objects but not scenes, however, with more ecologically valid naturalistic stimuli, VAB was large and robust, consistent with a vertical information imbalance that drives a generic downward vantage. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Children and adults exhibit a common vertical attention bias for object tops and scene bottoms.

Adults have a vertical attention bias (VAB) that directs their focus toward object tops and scene bottoms. This is consistent with focusing attention on the informative aspects and affordances of the environment, and generally favoring a downward gaze. The smaller size of children, combined with their relatively limited interactions with objects and scenes, could lead them to have diminished bias that only gradually develops. Alternatively, an early coupling of attention to action space could lead to VAB similar to adults. The current study investigates the developmental timeline of VAB, comparing 4-7-year-olds to adults. Participants (N = 50 children, 53 adults; 58% White, 22% Asian, 6% Black, 2% Native American, and 12% other) observed naturalistic photographic triptychs (48 objects, 52 scenes, all online). They made similarity judgments comparing a test figure to two flanking figures containing either the same top or same bottom. We found that (a) children and adults exhibit a common VAB for object tops and scene bottoms and (b) the adult bias is stronger than children's. Exploratory analyses revealed the same age trend within children, with VAB increasing with age, and asymptoting at the adult level at age 8. This demonstrates that despite age and body size differences that could make the environment for young children relatively disparate from adults, their perceptual system is already largely attuned to their individual interactive action space, with only minor continuing residual development. The findings support that, like adults, young children focus their attention on their action space and body level affordances, where they interact more with tops of objects and bottoms of scenes. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

The gleam-glum effect: /i:/ versus /λ/ phonemes generically carry emotional valence.

The gleam-glum effect is a novel sound symbolic finding that words with the /i:/-phoneme (like gleam) are perceived more positive emotionally than matched words with the /Λ/-phoneme (like glum). We provide data that not only confirm the effect but also are consistent with an explanation that /i:/ and /Λ/ articulation tend to co-occur with activation of positive versus negative emotional facial musculature respectively. Three studies eliminate selection bias by including all applicable English words from the English Lexicon Project (Balota et al., 2007) and the Warriner et al. (2013) database and every possible Mandarin Pinyin combination that differ only in the middle phoneme (/i:/ vs /Λ/). In Study 1, 61 U.S. undergraduates rated monosyllabic English /i:/ words as robustly more positive than matched /Λ/ words. Study 2 analyzed the Warriner et al. (2013) valence ratings, extending the gleam-glum effect to all applicable words in the database. In Study 3, 38 U.S. participants (using English) and 37 participants in China (using Mandarin Pinyin) rated word pairs under three conditions that moderate musculature activity: Read aloud (Enhance), read silently (Control), and read silently while chewing gum (Interfere). Indeed, the effect was both replicated and was significantly larger when facial musculature was enhanced than when interfered with, and the two language populations did not significantly differ. These findings confirm a robust gleam-glum effect, despite semantic noise, in English and Mandarin Pinyin. Furthermore, these data are consistent with the hypothesis that this type of sound symbolism arises from the overlap in muscles used both in articulation and emotion expression. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Egocentric Temporal Order Bias Robust Across Manipulations of Cue Predictability and Sensory Modality.

The Egocentric Temporal Order (ETO) bias is the finding that self-initiated action-events are perceived as having occurred prior to simultaneous externally triggered events. Here, we test if the ETO bias is affected by predictability of the stimulus cue used to initiate a self-action or by the sensory modality of that cue. Without separating out the potential influence of the stimulus cue on the ETO bias, further investigations into the mechanisms underlying the bias are difficult to interpret. Our findings robustly confirm and replicate the ETO bias, providing evidence that the bias is not an artifact of the experimental design, but rather indicates a true temporal bias in the perception of self-initiated action-events.

Perception of approaching and retreating floor-projected shapes in a large, immersive, multimedia learning environment.

Perception of floor-projected moving geometric shapes was examined in the context of the Situated Multimedia Arts Learning Laboratory (SMALLab), an immersive, mixed-reality learning environment. As predicted, the projected destinations of shapes which retreated in depth (proximal origin) were judged significantly less accurately than those that approached (distal origin). Participants maintained similar magnitudes of error throughout the session, and no effect of practice was observed. Shape perception in an immersive multimedia environment is comparable to the real world. One may conclude that systematic exploration of basic psychological phenomena in novel mediated environments is integral to an understanding of human behavior in novel human-computer interaction architectures.

Who hit the ball out? An egocentric temporal order bias.

Temporal order judgments can require integration of self-generated action events and external sensory information. We examined whether conscious experience is biased to perceive one's own action events to occur before simultaneous external events, such as deciding whether you or your opponent last touched a basketball heading out of bounds. Participants made temporal order judgments comparing their own touch to another participant's touch, a mechanical touch, or an auditory click. In all three manipulations, we find a robust bias to perceive self-generated action events to occur about 50 ms before external sensory events. We denote this bias to perceive self-actions earlier as the "egocentric temporal order" bias. Thus, if two players hit a ball nearly simultaneously, then both will likely have different subjective experiences of who touched last, leading to arguments.

Baseball's sight-audition farness effect (SAFE) when umpiring baserunners: Judging precedence of competing visual versus auditory events.

Baseball umpires judge force-outs at first-base by comparing the sound of ball-mitt contact to the sight of foot-base contact. This study examines if distant observer judgments of the temporal order of visual versus auditory events are biased due to the slow speed of sound, or if judgments made from farther away systematically compensate for acoustic delays of sound. Seventy and 81 participants observed videos projected onto a gymnasium wall from 0, 100, or 200 feet, and made multisensory precedence judgments regarding which cue occurred first, visual ("safe") or auditory ("out"). Experiment 1 used visual flash versus auditory click; Experiment 2, colliding visual stimuli versus auditory click; Experiment 3, films of base-runners with basemen catching balls. Our findings confirm a sight-audition farness effect (SAFE) bias such that when visual information is impoverished, distant observers making multisensory precedence judgments typically do not fully compensate for acoustic delays due to the slow speed of sound, which can lead to disagreements. In short, distant fans will tend to have more of a bias to experience baserunners as safe, compared with nearby umpires. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Auditory capture of visual apparent motion, both laterally and looming.

Traditional tests of multisensory stimuli typically support that vision dominates spatial judgments and audition dominates temporal ones. Here, we examine if unambiguous auditory spatial cues can capture ambiguous visual ones in judgments of direction of apparent motion. The visual motion judgments include both lateral movement and movement in depth, each when coupled with auditory stimuli moving at one of four rates. Experiment 1 tested lateral visual movement judgments (leftward vs rightward) coupled with auditory stimuli that moved laterally. Experiment 2 tested depth visual movement judgments (approaching vs receding) coupled with auditory stimuli that got louder or quieter. Results of Experiment 1 revealed and replicated an overall leftward motion bias, but with additional acoustic capture to experience visual movement away from the side on which sound initially occurred, and no effect of auditory motion speed. Results of Experiment 2 revealed and replicated an approaching motion bias, but with no effect of initial sound intensity, and an additional systematic capture effect of auditory motion speed. Faster changes in acoustic intensity produced larger visual motion capture consistent with the direction of acoustic intensity change. Findings of both experiments generalized over conditions of listening device (head phones vs speakers) and test-setting (Laboratory vs Web-based data-collection). The leftward and approaching motion bias results replicate previous research. Our principal new findings, the auditory motion capture effects, confirm the multisensory nature of dynamic spatial perception and support that extent of inter-sensory capture is a function of the relative reliability of spatial information acquired by each sensory modality.

Regularity of symmetry verticality guides perceptual judgments of objects.

Previous research indicated that most salient, real-world objects possess natural regularities that observers commonly assume in perceptual judgments of figural orientation and interpretation. Regularities include 3-dimensionality, bilateral symmetry, and the tendency for object tops to possess more salient information than bottoms. Thus, when observers interpret randomly shaped figures, they reliably impose volume, bilateral symmetry, and top and front orientation directions, even when figures are 2-dimensional and asymmetric. We confirmed generalizability for observers to assume these regularities with stimuli that vary in complexity, and we found evidence supporting another regularity, that of symmetry verticality (symmetry about a vertical axis). Findings support use of a family of perceptual heuristics corresponding to natural regularities that constrain stimulus indeterminacy and help guide judgment of object orientation and interpretation.

A unified fielder theory for interception of moving objects either above or below the horizon.

A unified fielder theory is presented that explains how humans navigate to intercept targets that approach from either above or below the horizon. Despite vastly different physical forces affecting airborne and ground-based moving targets, a common set of invariant perception-action principles appears to guide pursuers. When intercepting airborne projectiles, fielders keep the target image rising at a constant optical speed in a vertical image plane and moving in a constantoptical direction in an image plane that remains perpendicular to gaze direction. We confirm that fielders use the same strategies to intercept grounders. Fielders maintained a cotangent of gaze angle that decreases linearly with time (accounting for 98.7% of variance in ball speed) and a linear optical trajectory along an image plane that remains perpendicular to gaze direction (accounting for 98.2% of variance in ball position). The universality of maintaining optical speed and direction for both airborne and ground-based targets supports the theory that these mechanisms are domain independent.

Motion by nearby players biases perception but not action in judgments of baseball destination.

In this research, the influence of irrelevant reference frames on estimates of ball destination was examined. In 3 experiments, confederate base runners and fielders served as distractor stimuli while balls were rolled from home plate to random locations along a barrier hidden under an elevated tarp between first and second base. Stationary participants estimated the position that the ball would exit from under the tarp if there were no barrier, whereas running participants ran along the back edge of the barrier and touched the top of the tarp above where they believed the ball would exit. Estimates of ball destination were significantly biased in the direction opposite to the confederates' motion for stationary participants, but were accurate for running participants. These findings are consistent with other perception-action dissociations, and show that relative motion effects can occur in a naturalistic setting.

Naive beliefs in baseball: systematic distortion in perceived time of apex for fly balls.

When fielders catch fly balls they use geometric properties to optically maintain control over the ball. The strategy provides ongoing guidance without indicating precise positional information concerning where the ball is located in space. Here, the authors show that observers have striking misconceptions about what the motion of projectiles should look like from various perspectives and that they estimate when the physical apex of a fly ball occurs to be far later than actual, irrespective of baseball experience. Their estimations are consistent with the highest point they are looking at as the ball approaches, not with the physical apex. These findings introduce a new and robust effect in intuitive perception in which people confuse their perceptual perspective with the physical situation that they mentally represent.

The Galileo bias: a naive conceptual belief that influences people's perceptions and performance in a ball-dropping task.

This research introduces a new naive physics belief, the Galileo bias, whereby people ignore air resistance and falsely believe that all objects fall at the same rate. Survey results revealed that this bias is held by many and is surprisingly strongest for those with formal physics instruction. In 2 experiments, 98 participants dropped ball pairs varying in volume and/or mass from a height of 10 m, with the goal of both balls hitting the ground simultaneously. The majority of participants in both experiments adopted a single strategy consistent with the Galileo bias, showing no improvement across trials. Yet, for participants reporting intentions of dropping both balls at the same time, the differences between release points were significantly greater than 0 ms. These findings support separate but interacting cognition and perception-action systems.

Navigational strategy used to intercept fly balls under real-world conditions with moving visual background fields.

This study explored the navigational strategy used to intercept fly balls in a real-world environment under conditions with moving visual background fields. Fielders ran across a gymnasium attempting to catch fly balls that varied in distance and direction. During each trial, the launched balls traveled in front of a moving background texture that was projected onto an entire wall of a gymnasium. The background texture consisted of a field of random dots that moved together, at a constant speed and direction that varied between trials. The fielder route deviation was defined as the signed area swept out between the actual running path and a straight-line path to the destination, and these route deviation values were compared as a function of the background motion conditions. The findings confirmed that the moving visual background fields systematically altered the fielder running paths, which curved more forward and then to the side when the background gradient moved laterally with the ball, and curved more to the side and then forward when the background gradient moved opposite the ball. Fielder running paths deviated systematically, in a manner consistent with the use of a geometric optical control strategy that helps guide real-world perception-action tasks of interception, such as catching balls.

Baseball outfielders maintain a linear optical trajectory when tracking uncatchable fly balls.

The authors investigated whether behavior of fielders pursuing uncatchable fly balls supported either (a) maintenance of a linear optical trajectory (LOT) with monotonic increases in optical ball height or (b) maintenance of optical acceleration cancellation (OAC) with simultaneous lateral alignment with the ball. Past work supports usage of both LOT and OAC strategies in the pursuit of catchable balls headed to the side. When balls are uncatchable, fielders must choose either optical linearity or alignment at the expense of the other. Fielders maintained the LOT strategy more often and for a longer period of time than they did the OAC alignment strategy. Findings support the LOT strategy as primary when pursuing balls headed to the side, whether catchable or not.

A linear optical trajectory informs the fielder where to run to the side to catch fly balls.

P. McLeod, N. Reed, and Z. Dienes (2002) argued that the linear optical trajectory (LOT) strategy incorrectly cues fielders to run forward for balls headed beyond them. The authors of this article explain that the downward optical curvature found for balls landing beyond the fielder's initial position occurs because the balls reorient the direction the fielder is facing during pursuit. Thus, when downward optical curvature begins, the ball is headed to land in front of where the fielder is facing and running. This investigation of open-loop failure conditions has led to new insights such as the reorientation of the fielder, and it supports the use of maintaining matching rates of vertical and lateral optical ball movement consistent with primacy of the LOT control mechanism even when interception is unachievable.

The Doppler effect is not what you think it is: dramatic pitch change due to dynamic intensity change.

Historically, auditory pitch has been considered to be a function of acoustic frequency, with only a small effect being due to absolute intensity. Yet we found that when tones are Doppler shifted so that frequency drops, the pitch dramatically rises and falls, closely following the pattern of dynamic intensity change. We show that continuous intensity change can produce pitch variation comparable to a frequency change approaching an octave. This effect opposes and is an order of magnitude larger than the well-known effect of discrete intensity change in the frequency range employed. We propose that the perceptual interaction of continuous changes in pitch and loudness reflects a natural correlation between changes in frequency and intensity that is neurally encoded to facilitate the parsing and processing of meaningful acoustic patterns.