Object Knowledge Under Visual Crowding
Our visual environments are often complex and cluttered, which can challenge the perception of objects. In particular, when objects are seen in the visual periphery and are surrounded by other objects, we experience a phenomenon known as visual crowding, which impairs target identification. The processing of manipulable objects recruits different types of knowledge about their use and interaction. Such knowledge has been shown to influence cognitive processes involved in object perception, including object categorization, but only in relatively simple visual settings. It remains unclear whether these representations can also influence lower-level processes involved in object identification, and whether they may therefore help us identify objects in visually complex environments, particularly under visual crowding.
Visual Characteristics and Appearance of Positive Afterimages in Human Vision
Positive afterimages are visual experiences that persist briefly after a bright stimulus has been removed. They can be induced by a high-intensity flash following dark adaptation, creating an achromatic representation of the visual scene that can last for several seconds. The appearance of positive afterimages may also be influenced by higher-order cognitive processes. In this project, we investigate the temporal dynamics and visual characteristics of rod-mediated positive afterimages, and how they are influenced by factors such as visual imagery, stimulus meaningfulness, perceptual grouping, semantic memory, and social context. Using both psychophysical and qualitative methods, we aim to capture and understand how positive afterimages are perceived and experienced, from retinal physiology to phenomenology.
Foveal Redundancy Masking and Alternative Measures Beyond Enumeration
Redundancy masking refers to a compression of visual information in displays containing repetitive items. It has so far been well characterized in peripheral vision; however, it remains unclear whether it also occurs in foveal vision. More recently, we have aimed to develop alternative ways of measuring redundancy masking beyond explicit number reports. We explore appearance-based and perceptual measures that can reveal information loss.
Spatial Constraints on Numerosity Perception
Humans can rapidly estimate how many objects are present in a scene without explicitly counting. In this project, we ask how interactions between nearby objects shape the number of items that we consciously perceive. Across our studies, we found that arrangements that produced stronger visual interference make displays appear less numerous, from small sets of only a few objects to much larger sets. In particular, numerosity perception shows a radial-tangential anisotropy: objects arranged along the radial direction relative to fixation are perceived as less numerous than objects arranged tangentially.
Relevant papers:
L-Miao, L., Reynvoet, B., & Sayim, B. (2022).
Anisotropic representations of visual space modulate visual numerosity estimation
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Vision Research, 201, 108130.
L-Miao, L., Reynvoet, B., & Sayim, B. (2024).
The radial–tangential anisotropy of numerosity perception
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Journal of Vision, 24(7), 15.
Sustainability: Knowledge, Perception, and Behavior
Sustainability means meeting our needs while causing as little harm to the environment as possible. People differ not only in what they know about sustainability, but also in how that knowledge can be accessed and used when making decisions. In this project, we investigate how people understand the environmental impact of everyday actions, and how these judgments relate to perceptual and cognitive processes. By combining methods from psychophysics with sustainability research, we aim to understand how knowledge about environmental impact is accessed and used to guide behavior.