Visual processing recovers not only simple features, such as color and shape, but also seemingly higherlevel properties, such as animacy. Indeed, even abstract geometric shapes are readily perceived as intentional agents when they move in certain ways, and such percepts can dramatically influence behavior. In the wolfpack effect, for example, subjects maneuver a disc around a display in order to avoid several randomly moving darts. When the darts point toward the disc, subjects (falsely) perceive that the darts are chasing them, and this impairs several types of visuomotor performance. Are such effects reflexive, automatic features of visual processing? Or might they instead arise only as contingent strategies in tasks in which subjects must interact with (and thus focus on the features of) such objects? We explored these questions in an especially direct way-by embedding such displays into the background of a completely independent "foraging" task. Subjects now moved their disc to collect small "food" dots (which appeared sequentially in random locations) as quickly as possible. The darts were task-irrelevant, and subjects were encouraged to ignore them. Nevertheless, foraging was impaired when the randomly moving darts pointed at the subjects' disc, as compared to control conditions in which they were either oriented orthogonally to the subjects' disc or pointed at another moving shape-thereby controlling for nonsocial factors. The perception of animacy thus influences downstream visuomotor behavior in an automatic manner, such that subjects cannot completely override the influences of seemingly animate shapes even while attempting to ignore them.

A substantial body of literature supports the idea that systematic changes can occur in artists' painting styles after the onset of degenerating neurological illnesses like Alzheimer's disease or Fronto-temporal dementia. However, these studies have typically been descriptive and qualitative in their analyses. Our study was motivated to show that quantitative methods can be applied to the neuropsychology of art production and to determine whether there are systematic changes in the art produced by two individuals with Alzheimer's disease (AD). Using the Assessment of Art Attributes which probes 6 formal characteristics (depth, color temperature, color saturation, balance, stroke, and simplicity) and 6 conceptual characteristics (depictive accuracy, abstractness, emotion, symbolism, realism, and animacy), we found that both AD patients produced paintings with more abstraction and use of symbolism and with less depictive accuracy and realism. Their paintings did not change in the use of depth, or balance or in the quality of their stroke. When these observations are combined with those made recently in 3 artists with focal brain damage, we find that conceptual more than formal perceptual attributes are susceptible to change after neurological illness.

Of all the visual stimuli you can perceive, perhaps the most important are other people's eyes. And this is especially true when those eyes are looking at you: direct gaze has profound influences, even at the level of basic cognitive processes such as working memory. For example, memory for the properties of simple geometric shapes is disrupted by the presence of other eyes gazing at you. But are such effects really specific to direct gaze per se? Seeing eyes is undoubtedly important, but presumably only because of what it tells us about the "mind behind the eyes"i.e., about others' attention and intentions. This suggests that the same effects might arise even without eyes, as long as an agent's directed attention is conveyed by other means. Here we tested the impact on working memory of simple "mouth" shapeswhich in no way resemble eyes, yet can still be readily seen as intentionally facing you (or not). Just as with gaze cues, the ability to detect changes in geometric shapes was impaired by direct (compared to averted) mouthsbut not in very similar control stimuli that were not perceived as intentional. We conclude that this disruption of working memory reflects a general phenomenon of "mind contact," rather than a specific effect of eye contact.

One of the most foundational questions that can be asked about any visual process is the nature of the underlying 'units' over which it operates (e.g., features, objects, or spatial regions). Here we address this question-for the first time, to our knowledge-in the context of the perception of animacy. Even simple geometric shapes appear animate when they move in certain ways. Do such percepts arise whenever any visual feature moves appropriately, or do they require that the relevant features first be individuated as discrete objects? Observers viewed displays in which one disc (the "wolf") chased another (the "sheep") among several moving distractor discs. Critically, two pairs of discs were also connected by visible lines. In the Unconnected condition, both lines connected pairs of distractors; but in the Connected condition, one connected the wolf to a distractor, and the other connected the sheep to a different distractor. Observers in the Connected condition were much less likely to describe such displays using mental state terms. Furthermore, signal detection analyses were used to explore the objective ability to discriminate chasing displays from inanimate control displays in which the wolf moved toward the sheep's mirror-image. Chasing detection was severely impaired on Connected trials: observers could readily detect an object chasing another object, but not a line-end chasing another line-end, a line-end chasing an object, or an object chasing a line-end. We conclude that the underlying units of perceived animacy are discrete visual objects.

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Beyond seemingly lower-level features such as color and motion, visual perception also recovers properties more commonly associated with higher-level thought, as when an upwardly accelerating object is seen not just as moving, but moreover as self-propelled, and resisting the force of gravity. Given past research demonstrating the prioritization of living things in attention and memory, here we hypothesized that observers would be more sensitive to an object’s speed changes if those speed changes were opposite to natural gravitational acceleration. Across six experiments, we found that observers were more sensitive to objects’ accelerations when they moved upward (when those accelerations were opposite to gravity) and less sensitive to their accelerations when they moved downward (when those accelerations were consistent with gravity). Moreover, observers were more sensitive to objects’ decelerations when they moved downward (when those decelerations appeared as “braking” against gravity), and less sensitive to their decelerations when they moved upward (when those decelerations were consistent with gravity). This greater visual sensitivity to speed changes opposite to gravity is consistent with previous results suggesting that we readily monitor the world for cues to animacy.

Researchers in our field-like pretty much everyone else-seem to have a collective fascination with visual illusions. A recent Perception editorial, however, wonders whether this is a good idea (Braddick, 2018). In particular, while acknowledging plenty of useful research on (and inspired by) various individual illusions, Braddick asks whether it is really helpful to identify illusions more broadly as a category: "what have we gained by putting them in the same box. . .?" (p. 1). Braddick's suggestion is that doing so is a mistake motivated primarily by a superficial "innocent pleasure," but that illusions as a category are actually "deeply unhelpful for science" (p. 1). In an explicit attempt to be provocative, Braddick even suggests that focusing on illusions as a natural kind (i.e. as a privileged grouping that reflects something important about the structure of the mind) is an "infantile disorder." In this respect, Braddick's editorial succeeds admirably: we are provoked! In particular, we are provoked to explain why we disagree: we think that "illusions" are a natural kind whose existence has profound implications for our (scientific!) understanding of seeing, thinking, and especially how seeing and thinking do and do not interact. This is a theme that has figured quite a lot in recent debates about how cognition may influence perception, but curiously it was not mentioned either in Braddick's editorial or in subsequent defenses of the importance of illusions (e.g., Shapiro, 2018; Todorovic, 2018).

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