Denis Pelli

• PhD
• Professor at New York University

Online vision testing enables efficient data collection from diverse participants but requires accurate fixation. Fixation accuracy is traditionally ensured by using a camera to track gaze. That works well in the lab, but tracking during online testing with a built-in webcam is not yet sufficiently precise. Kurzawski, Pombo, et al. (2023) introduce...

Active object recognition, fundamental to tasks like reading and driving, relies on the ability to make time-sensitive decisions. People exhibit a flexible tradeoff between speed and accuracy, a crucial human skill. However, current computational models struggle to incorporate time. To address this gap, we present the first dataset (with 148 observ...

Past research shows that emotion affects beauty judgments of images and music. Because it is widely supposed that our faculty of empathy facilitates aesthetic experience, we wondered whether individual levels of empathy modulate the effect of emotion on beauty. 164 participants rated the perceived beauty, happiness, and sadness of 12 art images, 12...

Variance across participants is at the heart of the centuries-old debate about the universality of beauty. Beauty's belonging to the eye of the beholder implies large interindividual variance, while beauty as a universal object property implies the opposite. To characterize the variance at the center of this debate, we selected two quartets with ei...

Online methods allow testing of larger, more diverse populations, with much less effort than in-lab testing. However, many psychophysical measurements, including visual crowding, require accurate eye fixation, which is classically achieved by testing only experienced observers who have learned to fixate reliably, or by using a gaze tracker to restr...

What role do the emotions of subject and object play in judging the beauty of images and music? Eighty-one participants rated perceived beauty, liking, perceived happiness, and perceived sadness of 24 songs, 12 art images, and 12 nature photographs. Stimulus presentation was brief (2 seconds) or prolonged (20 seconds). The stimuli were presented in...

What spatial frequency information do humans and neural networks use to recognize objects? In neuroscience, critical band masking is an established tool that can reveal the frequency-selective filters used for object recognition. Critical band masking measures the sensitivity of recognition performance to noise added at each spatial frequency. Exis...

Crowding is the failure to recognize an object due to surrounding clutter. Our visual crowding survey measured 13 crowding distances (or "critical spacings") twice in each of 50 observers. The survey includes three eccentricities (0, 5, and 10 deg), four cardinal meridians, two orientations (radial and tangential), and two fonts (Sloan and Pelli)....

Information theory (bits) allows comparing beauty judgment to perceptual judgment on the same absolute scale. In one of the most influential articles in psychology, Miller (1956) found that classifying a stimulus into one of eight or more categories of the attribute transmits roughly 2.6 bits of information. That corresponds to 7 ± 2 categories. Th...

Recall memory and sequential dependence threaten the independence of successive beauty ratings. Such independence is usually assumed when using repeated measures to estimate the intrinsic variance of a rating. We call "intrinsic" the variance of all possible responses that the participant could give on a trial. Variance arises within and across par...

In one of the most influential papers in psychology, Miller (1956) found that classifying a stimulus into one of 8 or more categories of the attribute transmits roughly 2.6 bits of information. That corresponds to 7 ± 2 categories. This number is both remarkably small and highly conserved across attributes and sensory modalities. This appears to be...

The core of everyday tasks like reading and driving is active object recognition. Attempts to model such tasks are currently stymied by the inability to incorporate time. People show a flexible tradeoff between speed and accuracy and this tradeoff is a crucial human skill. Deep neural networks have emerged as promising candidates for predicting pea...

Intuitively, various factors contribute to beauty judgments. However, there is no empirical evidence that indicates whether rating beauty is unidimensional (e.g., like rating luminance) or multidimensional (e.g., like rating color). A few years after Shannon’s (1948) introduction of communication theory, Miller (1956) used mutual information to des...

Beauty judgments, at least in part, determine what we wear, where we eat, and who we swipe right on Tinder. However, beauty judgments vary greatly across individuals, and a new study highlights the importance of assessing these individual differences.

The intrinsic variance of a beauty rating is the essential baseline for evaluating how beauty ratings vary within and across individuals. Given independent repeated measures, it’s easy to estimate the variance of the distribution underlying one judgment. However, in the context of beauty, effects of assimilation, contrast, and recall-memory might p...

Sensory cortical mechanisms combine auditory or visual features into perceived objects. This is difficult in noisy or cluttered environments. Knowing that individuals vary greatly in their susceptibility to clutter, we wondered whether there might be a relation between an individual’s auditory and visual susceptibilities to clutter. In auditory mas...

Population receptive field (pRF) models fit to fMRI data are used to non-invasively measure retinotopic maps in human visual cortex, and these maps are a fundamental component of visual neuroscience experiments. Here, we examined the reproducibility of retinotopic maps across two datasets: a newly acquired retinotopy dataset from New York Universit...

Many philosophers and psychologists have made claims about what is felt in an experience of beauty. Here, we test how well these claims match the feelings that people report while looking at an image, or listening to music, or recalling a personal experience of beauty. We conducted ten experiments (total n = 851) spanning three nations (US, UK, and...

Measuring intraindividual variability of beauty judgment is key to understanding the repeatability of beauty ratings within and between individuals. To calculate intraindividual variability using repeated measures, the repeated measures must be independent. Sequential dependencies, which occur when previous ratings influence following ones, threate...

Population receptive field (pRF) models fit to fMRI data are used to non-invasively measure retinotopic maps in human visual cortex, and these maps are a fundamental component of visual neuroscience experiments. Here, we examined the reproducibility of retinotopic maps across two datasets: a newly acquired retinotopy dataset from New York Universit...

The intrinsic variance of beauty judgment is key to modeling beauty ratings. However, in repeated measures of beauty, observers surely make use of what they remember. To test how memory contributes to repeated beauty ratings, we asked participants to rate 75 arbitrarily named images (e.g., Fred). Initially, participants rated (1 to 7) how much beau...

In noisy or cluttered environments, sensory cortical mechanisms help combine auditory or visual features into perceived objects. Knowing that individuals vary greatly in their ability to suppress unwanted sensory information, and knowing that the sizes of auditory and visual cortical regions are correlated, we wondered whether there might be a corr...

Crowding is the failure to recognize an object due to surrounding clutter. Its strength varies across the visual field and individuals. To characterize the statistics of crowding—ultimately to relate psychophysics of crowding to physiology—we measured radial crowding distance and acuity of 105 observers along the four cardinal meridians of the visu...

A Correction to this paper has been published: https://doi.org/10.3758/s13414-020-02218-5

Neural networks today often recognize objects as well as people do, and thus might serve as models of the human recognition process. However, most such networks provide their answer after a fixed computational effort, whereas human reaction time varies, e.g. from 0.2 to 10 s, depending on the properties of stimulus and task. To model the effect of...

Many philosophers and psychologists have made claims about the feelings in an experience of beauty. Here, we test how well these claims match the feelings that people report while looking at an image or listening to music that is beautiful to them, or recalling a personal experience of beauty. We conducted ten experiments (total n = 851) spanning t...

How many pleasures can you track? In a previous study, we showed that people can simultaneously track the pleasure they experience from two images. Here, we push further, probing the individual and combined pleasures felt from seeing four images in one glimpse. Participants (N = 25) viewed 36 images spanning the entire range of pleasure. Each trial...

For Bentham (1781), pleasure is the only value that matters. To test this, we used an auction task to measure the monetary value of three different kinds of object: postcards, snacks, and money lotteries. Undergraduate students bid up to $4.00 on each item. They also viewed each stimulus and rated how much pleasure they felt from it on a scale of 1...

Scene text recognition models have advanced greatly in recent years. Inspired by human reading we characterize two important scene text recognition models by measuring their domains i.e. the range of stimulus images that they can read. The domain specifies the ability of readers to generalize to different word lengths, fonts, and amounts of occlusi...

Choosing often demands that we assess the pleasures of multiple objects at once. Last year at VSS, we showed that people can keep track of at least two pleasures independently. Here, we probe this limit and ask whether they can also track four. Participants (N = 18) viewed 36 OASIS images that uniformly span the entire range of pleasure (from very...

Many philosophers, including Plato, Aristotle, Kant, and Hegel, gave normative definitions of beauty. But do these definitions match how people experience beauty today? And how similar are the felt beauties of music and images? We presented songs (N = 93) and art- and stock-images (N = 99). For each one, we asked participants to use 7-point scales...

The relation of morality to aesthetics matters in many fields, including social, perceptual, and cognitive psychology. Moral and aesthetic judgments mutually influence one another: People’s physical attractiveness influences how honest and trustworthy they appear, and people’s character influences how we judge their appearance. However, previous st...

For Bentham (1781), pleasure is the only value that matters. To test this, we used an auction task to measure the monetary value of three different kinds of object: postcards, snacks, and money lotteries. Undergraduate students bid up to $4.00 on each item. They also viewed each stimulus and rated how much pleasure they felt from it on a scale of 1...

Can people track several pleasures? In everyday life, pleasing stimuli rarely appear in isolation. Yet, experiments on aesthetic pleasure usually present only one image at a time. Here, we ask whether people can reliably report the pleasure of either of two images seen in a single glimpse. Participants (N = 13 in the original; +25 in the preregiste...

At the beginning of psychology, Fechner (1876) claimed that beauty is immediate pleasure, and that an object’s pleasure determines its value. In our earlier work, we found that intense pleasure always results in intense beauty. Here, we focus on the inverse: Is intense pleasure necessary for intense beauty? If so, the inability to experience pleasu...

Many philosophers, including Plato, Kant, and Hegel, gave normative definitions of beauty. For instance, Kant claimed that beauty entails a disinterested pleasure that feels universal. But do these definitions match how people experience beauty today? To answer this question, we asked 100 participants to rate their experience of 15 images (pre-rate...

Since the beginning of psychology, researchers have tried to understand beauty. Here, we address two of the oldest questions about it. First, Fechner (1876) claimed that beauty is immediate pleasure, and that an object’s pleasure determines its value. Focusing on the first claim, if beauty is pleasure then inability to experience pleasure (anhedoni...

Neuroaesthetics is a rapidly developing interdisciplinary field of research that aims to understand the neural substrates of aesthetic experience: While understanding aesthetic experience has been an objective of philosophers for centuries, it has only more recently been embraced by neuroscientists. Recent work in neuroaesthetics has revealed that...

Abstract for poster at VSS2108. See forthcoming article in Neuroimage.

Philosophers claim that beauty is a kind of pleasure. Here, we empirically test a mathematical model that describes the beauty-pleasure relation. Participants (N=18) continuously rate pleasure while viewing images for 5 s and for another 10 s after. At the end of each trial, they rate their overall feeling of beauty on a four-point scale. First, we...

Philosophers, psychologists, and common sense agree that beauty is a kind of pleasure. Here, we assess the relationships between the intensity of beauty, valence (pleasure vs. displeasure), arousal (calm vs. excited), anhedonia, and depression. We use the 900 OASIS images and their normative valence and arousal scores. In this study, 757 participan...

Today many vision-science presentations employ machine learning, especially the version called “deep learning”. Many neuroscientists use machine learning to decode neural responses. Many perception scientists try to understand how living organisms recognize objects. To them, deep neural networks offer benchmark accuracies for recognition of learned...

Our everyday lives are full of aesthetic experiences. We wake up and frown at an overcast sky, or smile at the sight of the sun. Myriad decisions depend on the aesthetic appeal of the available options like which shirt to wear, which route to take to work, or where to eat. Even life-changing decisions, like where to live or who to live with, are pa...

Beauty is described as one of the goals of humankind, alongside truth and goodness. Values are the basis for decision making. In decision theory, a rational decision maker’s preferences will be transitive along the dimension of expected value. Is beauty a value? Are our beauty preferences transitive? If so, then beauty ratings must be one-dimension...

Can observers keep track of each pleasure, while enjoying several? In everyday life, pleasing images are rarely isolated. Yet, experiments on aesthetic pleasure usually present only one image at a time. Here we ask whether people can reliably report the pleasure of an image even if another image is presented simultaneously and both need to be atten...

Over time, how does beauty develop and decay? Common sense suggests that beauty is intensely felt only after prolonged experience of the object. Here, we present one of various stimuli for a variable duration (1-30 s), measure the observers' pleasure over time, and, finally, ask whether they felt beauty. On each trial, participants (N = 21) either...

In everyday life, pleasing images are rarely isolated. Yet, experiments on aesthetic pleasure usually present only one image at a time. Here we ask whether people can reliably report the pleasure of an image even if another image is presented simultaneously. Participants (N=14) viewed 36 OASIS-3-database images that uniformly span the entire range...

Philosophers claim that beauty is a kind of pleasure. We empirically investigate the perceptual processes underlying beauty experiences. In our experiments, participants continuously rate their pleasure while experiencing various stimuli (seeing images of various kinds, touching an unseen teddy bear, eating candy) and for another 60 s after. And, a...

The experience of beauty is a pleasure, but common sense and philosophy suggest that feeling beauty differs from sensuous pleasures such as eating or sex. Immanuel Kant [1, 2] claimed that experiencing beauty requires thought but that sensuous pleasure can be enjoyed without thought and cannot be beautiful. These venerable hypotheses persist in mod...

Visual agnosia is a neuropsychological impairment of visual object recognition despite near-normal acuity and visual fields. A century of research has provided only a rudimentary account of the functional damage underlying this deficit. We find that the object-recognition ability of agnosic patients viewing an object directly is like that of normal...

Imagine catching a glimpse of Monet's Water Lilies in an art museum. How long must one look at an image to experience beauty? We examined how exposure duration affects the experience of beauty. Before the experiment, we asked participants to, "pick images that are movingly beautiful to you" from Google images. We also selected moderately rated non-...

People readily distinguish beauty experiences from other mundane pleasures. This intuition is reflected in models of aesthetic experience and confirmed by fMRI evidence that prefrontal regions and the default mode network are selectively involved in experiencing beauty. This is consistent with Immanuel Kant's notion that "beauty requires thought" b...

We report a connection between effects of crowding and noise. In the periphery, it is impossible to identify a target in clutter, unless the clutter is at least a critical spacing away. The area enclosed by the critical spacing is the "combining field". Measuring thresholds in various levels of full-field white noise, we decompose threshold contras...

People spend incredible amounts of money for original artworks and live music. Why? Perfect copies and high-quality recordings are available for less than one percent the price. Newman and Bloom (2012) have shown that people assign a higher monetary value to art objects that have had direct contact with the artist, suggesting that authenticity is k...

People readily distinguish beauty experiences from other mundane pleasures. Immanuel Kant famously noted that “beauty requires thought”. Here we experimentally test Kant’s hypothesis. Participants were presented with beautiful images (self- or experimenter-selected), ordinary pleasures (pretty image or eating candy), or neutral images for 30 s. Dur...

People readily distinguish beauty experiences from other mundane pleasures. This intuition is confirmed by fMRI evidence that prefrontal regions involved in working memory and the default mode network are selectively involved in experiencing beauty. This suggests that Immanuel Kant’s notion that “beauty requires thought” may apply to neural process...

Crowding is a major limitation of visual perception. Because of crowding, a simple object, like a letter, can only be recognized if clutter is a certain critical spacing away. Crowding is only weakly associated with acuity. The critical spacing of crowding is lowest in the normal fovea, and grows with increasing eccentricity in peripheral vision. F...

The limits to human visual sensitivity can be factored into equivalent input noise, mostly due to unreliable communication, and efficiency, mostly due to suboptimal algorithms.

Grouping and crowding have each received much study, but, because they can be avoided, they have seemed marginal to the mystery of how people recognize objects. We begin by showing that the same image parameters that promote grouping also promote crowding. Joining grouping and crowding theories suggests a unified account in which grouping and crowd...

Visual agnosia is a neuropsychological impairment of visual object recognition. In spite of over a century of research, little is known about the nature of the functional damage underlying this deficit. We propose that the agnosic deficit is visual crowding: The central vision of agnosic patients is crowded, like the peripheral vision of normally s...

When you look at your beauty and I look at mine, do we have the same feeling? Kant (1764) and Santayana (1896) say that the experience of beauty is pleasure, with qualifications. So we measure pleasure. Observers use Google Images to find an image that is beautiful to them. The observer is asked to look at that image and rate pleasure by continuall...

Theinability to recognize a peripheral target among flankers is called crowding. For a foveal target, crowding can be distinguished from overlap masking by its sparing of detection, linear scaling with eccentricity, and invariance with target size.Crowding depends on the proximity and similarity of the flankers to the target. Flankers that are far...

CROWDING IS THE INABILITY TO IDENTIFY AN OBJECT AMONG FLANKERS IN THE PERIPHERY: It is due to inappropriate incorporation of features from flanking objects in perception of the target. Crowding is characterized by measuring critical spacing, the minimum distance needed between a target and flankers to allow recognition. The existing Bouma law state...

Background / Purpose: We have implemented two machine-learning models of object recognition by human observers. Both models capture three hallmarks of human performance that cannot be accounted for by template matching: spatial frequency channels, crowding, effects of letter complexity. One model is a Convolutional Neural Network (ConvNet), a...

Background / Purpose: We studied the duration of pleasure in the experience of beauty. Main conclusion: We found that high, long-lasting pleasure is a hallmark of the beauty response.

Here, we systematically explore the size and spacing requirements for identifying a letter among other letters. We measure acuity for flanked and unflanked letters, centrally and peripherally, in normals and amblyopes. We find that acuity, overlap masking, and crowding each demand a minimum size or spacing for readable text. Just measuring flanked...

We have implemented two machine-learning models of object recognition by human observers. Both models capture two hallmarks of human performance: (1) spatial frequency channels, (2) effects of font complexity. One model is a Convolutional Neural Network (ConvNet), and the other is a texture statistics model followed by a simple classifier. With app...