Visual event boundaries restrict anchoring effects in decision-making.

Research on higher-level thought has revealed many principles of reasoning and decision-making but has rarely made contact with how we perceive the world in the first place. Here we show how a lower-level property of perception-the spontaneous and task-irrelevant segmentation of continuous visual stimulation into discrete events-can restrict one of the most notorious biases in decision-making: numerical anchoring. Subjects walked down a long room in an immersive three dimensional (3D) animation and then made a numerical judgment (e.g., of how much a suitcase is worth, or of how many hours of community service a minor crime deserved). Critically, some subjects passed through a doorway (a visual event boundary) during their virtual walk, while others did not-equating time, distance traveled, and visual complexity. The anchoring manipulation was especially innocuous, not appearing to be part of the experiment at all. Before the online trial began, subjects reported the two-digit numerical value from a visually distorted "CAPTCHA" ("to verify that you are human")-where this task-irrelevant anchor was either low (e.g., 29) or high (e.g., 92). With no doorway, we observed reliable anchoring effects: Higher CAPTCHA values produced higher estimates. With the doorway, however, such effects were attenuated or even eliminated. This generalized across tasks involving item valuations, factual questions, and legal judgments and in tests of both incidental and explicit anchoring. This demonstrates how spontaneous visual event segmentation can have profound consequences for higher-level thought.

Perceptual (roots of) core knowledge.

Some core knowledge may be rooted in - or even identical to - well-characterized mechanisms of mid-level visual perception and attention. In the decades since it was first proposed, this possibility has inspired (and has been supported by) several discoveries in both infant cognition and adult perception, but it also faces several challenges. To what degree does What Babies Know reflect how babies see and attend?

Seeing Soft Materials Draped Over Objects: A Case Study of Intuitive Physics in Perception, Attention, and Memory.

We typically think of intuitive physics in terms of high-level cognition, but might aspects of physics also be extracted during lower-level visual processing? Might we not only think about physics, but also see it? We explored this using multiple tasks in online adult samples with objects covered by soft materials-as when you see a chair with a blanket draped over it-where you must account for the physical interactions between cloth, gravity, and object. In multiple change-detection experiments (n = 200), observers from an online testing marketplace were better at detecting image changes involving underlying object structure versus those involving only the superficial folds of cloths-even when the latter were more extreme along several dimensions. And in probe-comparison experiments (n = 100), performance was worse when both probes (vs. only one) appeared on image regions reflective of underlying object structure (equating visual properties). This work collectively shows how vision uses intuitive physics to recover the deeper underlying structure of scenes.

Gaze deflection reveals how gaze cueing is tuned to extract the mind behind the eyes.

Suppose you are surreptitiously looking at someone, and then when they catch you staring at them, you immediately turn away. This is a social phenomenon that almost everyone experiences occasionally. In such experiences-which we will call gaze deflection-the "deflected" gaze is not directed at anything in particular but simply away from the other person. As such, this is a rare instance where we may turn to look in a direction without intending to look there specifically. Here we show that gaze cues are markedly less effective at orienting an observer's attention when they are seen as deflected in this way-even controlling for low-level visual properties. We conclude that gaze cueing is a sophisticated mental phenomenon: It is not merely driven by perceived eye or head motions but is rather well tuned to extract the "mind" behind the eyes.

Gazing Without Eyes: A "Stare-in-the-Crowd" Effect Induced by Simple Geometric Shapes.

Of the many effects that eye contact has, perhaps the most powerful is the stare-in-the-crowd effect, wherein faces are detected more readily when they look directly toward you. This is commonly attributed to others' eyes being especially salient visual stimuli, but here we ask whether stares-in-the-crowd might arise instead from a deeper property that the eyes (but not only the eyes) signify: the direction of others' attention and intentions. In fact, even simple geometric shapes can be seen as intentional, as when numerous randomly scattered cones are all consistently pointing at you. Accordingly, we show here that cones directed at the observer are detected faster (in fields of averted cones) than are cones averted away from the observer (in fields of directed cones). These results suggest that perceived intentionality itself captures attention-and that even in the absence of eyes, others' directed attention stands out in a crowd.

How to Create Objects With Your Mind: From Object-Based Attention to Attention-Based Objects.

When staring at a blank grid, one can readily "see" simple shapes-a peculiar experience that does not occur when viewing an empty background. But just what does this "seeing" entail? Previous work has explored many cues to object-based attention (e.g., involving continuity and closure), but here we asked whether attention can be object based even when there are no cues to objecthood. Observers viewed simple grids and attended to particular squares until they could effectively "see" shapes such as a capital H or I. During this scaffolded attention, two probes appeared, and observers reported whether they were the same or different. Remarkably, this produced a traditional same-object advantage: In several experiments (including high-powered direct replications), performance was enhanced for probes presented on the same (purely imagined) object, compared with equidistant probes presented on different objects. We conclude that attention not only operates over objects but also can effectively create object representations.

Motion-induced blindness for dynamic targets: Further explorations of the perceptual scotoma hypothesis.

Motion-induced blindness (MIB) is a striking phenomenon wherein fully visible and attended objects may repeatedly fluctuate into and out of conscious awareness when superimposed onto certain global moving patterns. Perhaps the most remarkable feature of MIB is that objects can disappear even when they are moving. Here we report several novel demonstrations of MIB for dynamic objects, including the observations that (a) MIB can occur for dynamic targets defined by various types of complex visual distortions (akin to those that may occur with various types of metamorphopsias), and (b) MIB is more robust for downward-drifting compared to upward-drifting objects (perhaps because of the related motions of floaters in the eye's vitreous humor). To interpret these results, we focus on the idea that MIB may arise not from a limitation or failure of visual processing, but instead from a perceptual scotoma: MIB may reflect a functional inference in visual processing, eliminating some novel stimuli from awareness in much the same way that the visual system chronically eliminates percepts that would otherwise arise from visual impairments (such as scotomas) or features that are not in the external world in the first place (such as shadows from retinal blood vessels).

The Perception of History: Seeing Causal History in Static Shapes Induces Illusory Motion Perception.

The perception of shape, it has been argued, also often entails the perception of time. A cookie missing a bite, for example, is seen as a whole cookie that was subsequently bitten. It has never been clear, however, whether such observations truly reflect visual processing. To explore this possibility, we tested whether the perception of history in static shapes could actually induce illusory motion perception. Observers watched a square change to a truncated form, with a "piece" of it missing, and they reported whether this change was sudden or gradual. When the contours of the missing piece suggested a type of historical "intrusion" (as when one pokes a finger into a lump of clay), observers actually saw that intrusion occur: The change appeared to be gradual even when it was actually sudden, in a type of transformational apparent motion. This provides striking phenomenological evidence that vision involves reconstructing causal history from static shapes.

Seeing and thinking: Foundational issues and empirical horizons.

The spectacularly varied responses to our target article raised big-picture questions about the nature of seeing and thinking, nitty-gritty experimental design details, and everything in between. We grapple with these issues, including the ready falsifiability of our view, neuroscientific theories that allow everything but demand nothing, cases where seeing and thinking conflict, mental imagery, the free press, an El Greco fallacy fallacy, hallucinogenic drugs, blue bananas, subatomic particles, Boeing 787s, and the racial identities of geometric shapes.

Cognition does not affect perception: Evaluating the evidence for "top-down" effects.

What determines what we see? In contrast to the traditional "modular" understanding of perception, according to which visual processing is encapsulated from higher-level cognition, a tidal wave of recent research alleges that states such as beliefs, desires, emotions, motivations, intentions, and linguistic representations exert direct, top-down influences on what we see. There is a growing consensus that such effects are ubiquitous, and that the distinction between perception and cognition may itself be unsustainable. We argue otherwise: None of these hundreds of studies - either individually or collectively - provides compelling evidence for true top-down effects on perception, or "cognitive penetrability." In particular, and despite their variety, we suggest that these studies all fall prey to only a handful of pitfalls. And whereas abstract theoretical challenges have failed to resolve this debate in the past, our presentation of these pitfalls is empirically anchored: In each case, we show not only how certain studies could be susceptible to the pitfall (in principle), but also how several alleged top-down effects actually are explained by the pitfall (in practice). Moreover, these pitfalls are perfectly general, with each applying to dozens of other top-down effects. We conclude by extracting the lessons provided by these pitfalls into a checklist that future work could use to convincingly demonstrate top-down effects on visual perception. The discovery of substantive top-down effects of cognition on perception would revolutionize our understanding of how the mind is organized; but without addressing these pitfalls, no such empirical report will license such exciting conclusions.

Object Persistence Enhances Spatial Navigation: A Case Study in Smartphone Vision Science.

Violations of spatiotemporal continuity disrupt performance in many tasks involving attention and working memory, but experiments on this topic have been limited to the study of moment-by-moment on-line perception, typically assessed by passive monitoring tasks. We tested whether persisting object representations also serve as underlying units of longer-term memory and active spatial navigation, using a novel paradigm inspired by the visual interfaces common to many smartphones. Participants used key presses to navigate through simple visual environments consisting of grids of icons (depicting real-world objects), only one of which was visible at a time through a static virtual window. Participants found target icons faster when navigation involved persistence cues (via sliding animations) than when persistence was disrupted (e.g., via temporally matched fading animations), with all transitions inspired by smartphone interfaces. Moreover, this difference occurred even after explicit memorization of the relevant information, which demonstrates that object persistence enhances spatial navigation in an automatic and irresistible fashion.

"Please tap the shape, anywhere you like": Shape skeletons in human vision revealed by an exceedingly simple measure.

A major challenge for visual recognition is to describe shapes flexibly enough to allow generalization over different views. Computer vision models have championed a potential solution in medial-axis shape skeletons-hierarchically arranged geometric structures that are robust to deformations like bending and stretching. In the experiments reported here, we exploited an old, unheralded, and exceptionally simple paradigm to reveal the presence and nature of shape skeletons in human vision. When participants independently viewed a shape on a touch-sensitive tablet computer and simply tapped the shape anywhere they wished, the aggregated touches formed the shape's medial-axis skeleton. This pattern held across several shape variations, demonstrating profound and predictable influences of even subtle border perturbations and amodally filled-in regions. This phenomenon reveals novel properties of shape representation and demonstrates (in an unusually direct way) how deep and otherwise-hidden visual processes can directly control simple behaviors, even while observers are completely unaware of their existence.

"Top-down" effects where none should be found: the El Greco fallacy in perception research.

A tidal wave of recent research purports to have discovered that higher-level states such as moods, action capabilities, and categorical knowledge can literally and directly affect how things look. Are these truly effects on perception, or might some instead reflect influences on judgment, memory, or response bias? Here, we exploited an infamous art-historical reasoning error (the so-called "El Greco fallacy") to demonstrate that multiple alleged top-down effects (including effects of morality on lightness perception and effects of action capabilities on spatial perception) cannot truly be effects on perception. We suggest that this error may also contaminate several other varieties of top-down effects and that this discovery has implications for debates over the continuity (or lack thereof) of perception and cognition.

"Visual verbs": Dynamic event types are extracted spontaneously during visual perception.

During visual processing, input that is continuous in space and time is segmented, resulting in the representation of discrete tokens-objects or events. And there has been a great deal of research about how object representations are generalized into types-as when we see an object as an instance of a broader category (e.g., an animal or plant). There has been much less attention, however, to the possibility that vision represents dynamic information in terms of a small number of primitive event types (such as twisting or bouncing). (In models that posit a "language of vision," these would be the foundational visual verbs.) Here we ask whether such event types are extracted spontaneously during visual perception, even when entirely task irrelevant during passive viewing. We exploited the phenomenon of categorical perception-wherein differences are more readily noticed when they are represented in terms of different underlying categories. Observers were better at detecting changes to images or short videos when the changes involved switches in the underlying event type-even when the changes that maintained the same event type were objectively larger (in terms of both brute image metrics and higher level feature change). We observed this categorical "cross-event-type" advantage for visual working memory for twisting versus rotating, scooping versus pouring, and rolling versus bouncing. Moreover, additional control experiments confirmed that such effects could not be explained by appeal to lower-level non-categorical stimulus differences. This spontaneous perception of "visual verbs" might promote both generalization and prediction about how events are likely to unfold. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Spontaneous path tracing in task-irrelevant mazes: Spatial affordances trigger dynamic visual routines.

Given a maze (e.g., in a book of puzzles), you might solve it by drawing out paths with your pencil. But even without a pencil, you might naturally find yourself mentally tracing along various paths. This "mental path tracing" may intuitively seem to depend on your (overt, conscious, voluntary) goal of wanting to get out of the maze, but might it also occur spontaneously-as a result of simply seeing the maze, via a kind of dynamic visual routine? Here, observers simply had to compare the visual properties of two probes presented in a maze. The maze itself was entirely task irrelevant, but we predicted that simply seeing the maze's visual structure would "afford" incidental mental path tracing (à la Gibson). Across four experiments, observers were slower to compare probes that were further from each other along the paths, even when controlling for lower level properties (such as the probes' brute linear separation, ignoring the maze "walls"). These results also generalized beyond mazes to other unfamiliar displays with task-irrelevant circular obstacles. This novel combination of two prominent themes from our field-affordances and visual routines-suggests that at least some visual routines may not require voluntary goals; instead, they may operate in an automatic (incidental, stimulus-driven) fashion, as a part of visual processing itself. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

What's next?: Time is subjectively dilated not only for 'oddball' events, but also for events immediately after oddballs.

Our experience of time is strikingly plastic: Depending on contextual factors, the same objective duration can seem to fly by or drag on. Perhaps the most direct demonstration of such subjective time dilation is the oddball effect: when seeing identical objects appear one after another, followed by an "oddball" (e.g., a disc that suddenly grows in size, in a sequence of otherwise static discs), observers experience this oddball as having lasted longer than its nonoddball counterparts. Despite extensive work on this phenomenon, a surprisingly foundational question remains unasked: What actually gets dilated? Beyond the oddball, are the objects just before (or just after) the oddball also dilated? As in previous studies, observers viewed sequences of colored discs, one of which could be the oddball-and subsequently reproduced the oddball's duration. Unlike previous studies, however, there were also critical trials in which observers instead reproduced the duration of the disc immediately before or after the oddball. A clear pattern emerged: oddball-induced time dilation extended to the post-oddball disc, but not the pre-oddball disc. Whence this temporal asymmetry? We suggest that an oddball's sudden appearance may induce uncertainty about what will happen next, heightening attention until after the uncertainty is resolved.

Perceived gaze dynamics in social interactions can alter (and even reverse) the perceived temporal order of events.

Here's an all-too-familiar scenario: Person A is staring at person B, and then B turns toward A, and A immediately looks away (a phenomenon we call 'gaze deflection'). Beyond perceiving lower-level properties here - such as the timing of the eye/head turns - you can also readily perceive seemingly higher-level social dynamics: A got caught staring, and frantically looked away in embarrassment! It seems natural to assume that such social impressions are based on more fundamental representations of what happened when - but here we show that social gaze dynamics are unexpectedly powerful in that they can actually alter (and even reverse) the perceived temporal order of the underlying events. Across eight experiments, observers misperceived B as turning before A, when in fact they turned simultaneously - and even when B was turning after A. Additional controls confirmed that this illusion depends on visual processing (vs. being driven solely by higher-level interpretations), and that it is specific to the perception of social agents (vs. non-social objects). This demonstrates how social perception is tightly integrated into our perceptual experience of the world, and can have powerful consequences for one of the most basic properties that we can perceive: what happens when.

Dissociating the detection of intentionality from animacy in the right posterior superior temporal sulcus.

Certain motion patterns can cause even simple geometric shapes to be perceived as animate. Viewing such displays evokes strong activation in temporoparietal cortex, including areas in and near the (predominantly right) posterior superior temporal sulcus (pSTS). These brain regions are sensitive to socially relevant information, but the nature of the social information represented in pSTS is unclear. For example, previous studies have been unable to explore the perception of shifting intentions beyond animacy. This is due in part to the ubiquitous use of complex displays that combine several types of social information, with little ability to control lower-level visual cues. Here we address this challenge by manipulating intentionality with parametric precision while holding cues to animacy constant. Human subjects were exposed to a "wavering wolf" display, in which one item (the wolf) chased continuously, but its goal (i.e., the sheep) frequently switched among other shapes. By contrasting this with three other control displays, we find that the wolf's changing intentions gave rise to strong selective activation in the right pSTS, compared with (1) a wolf that chases with a single unchanging intention, (2) very similar patterns of motion (and motion change) that are not perceived as goal-directed, and (3) abrupt onsets and offsets of moving objects. These results demonstrate in an especially well controlled manner that right pSTS is involved in social perception beyond physical properties such as motion energy and salience. More importantly, these results demonstrate for the first time that this region represents perceived intentions beyond animacy.