In visual perception, an optical illusion is an illusion caused by the visual system and characterized by a visual percept that arguably appears to differ from reality. Illusions come in a wide variety; their categorization is difficult because the underlying cause is often not clear but a classification proposed by Richard Gregory is useful as an orientation. According to that, there are three main classes: physical, physiological, and cognitive illusions, and in each class there are four kinds: Ambiguities, distortions, paradoxes, and fictions. A classical example for a physical distortion would be the apparent bending of a stick half immerged in water; an example for a physiological paradox is the motion aftereffect. An example for a physiological fiction is an afterimage. Three typical cognitive distortions are the Ponzo, Poggendorff, and Müller-Lyer illusion. Physical illusions are caused by the physical environment, e.g. by the optical properties of water. Physiological illusions arise in the eye or the visual pathway, e.g. from the effects of excessive stimulation of a specific receptor type. Cognitive visual illusions are the result of unconscious inferences and are perhaps those most widely known.
Lip reading, also known as speechreading, is a technique of understanding a limted range of speech by visually interpreting the movements of the lips, face and tongue without sound. Estimates of the range of lip reading vary, with some figures as low as 30% because lip reading relies on context, language knowledge, and any residual hearing. Although lip reading is used most extensively by deaf and hard-of-hearing people, most people with normal hearing process some speech information from sight of the moving mouth.
The McGurk effect is a perceptual phenomenon that demonstrates an interaction between hearing and vision in speech perception. The illusion occurs when the auditory component of one sound is paired with the visual component of another sound, leading to the perception of a third sound. The visual information a person gets from seeing a person speak changes the way they hear the sound. If a person is getting poor-quality auditory information but good-quality visual information, they may be more likely to experience the McGurk effect. Integration abilities for audio and visual information may also influence whether a person will experience the effect. People who are better at sensory integration have been shown to be more susceptible to the effect. Many people are affected differently by the McGurk effect based on many factors, including brain damage and other disorders.
Facial perception is an individual's understanding and interpretation of the face. Here, perception implies the presence of consciousness and hence excludes automated facial recognition systems. Although facial recognition is found in other species, this article focuses on facial perception in humans.
Michelle Dawson is a Canadian autism researcher who was diagnosed with autism in 1993–1994. Since 2004, she has worked as an autism researcher affiliated with the Autism Specialized Clinic of Hôpital Rivière-des-Prairies in Montreal, Quebec, Canada.
Sensory substitution is a change of the characteristics of one sensory modality into stimuli of another sensory modality.
David J. Heeger is an American neuroscientist, psychologist, computer scientist, data scientist, and entrepreneur. He is a professor at New York University, Chief Scientific Officer of Statespace Labs, and Chief Scientific Officer and co-founder of Epistemic AI.
Within computer technology, the gaze-contingency paradigm is a general term for techniques allowing a computer screen display to change in function depending on where the viewer is looking. Gaze-contingent techniques are part of the eye movement field of study in psychology.
In cognitive neuroscience, visual modularity is an organizational concept concerning how vision works. The way in which the primate visual system operates is currently under intense scientific scrutiny. One dominant thesis is that different properties of the visual world require different computational solutions which are implemented in anatomically/functionally distinct regions that operate independently – that is, in a modular fashion.
The greebles are artificial objects designed to be used as stimuli in psychological studies of object and face recognition. They were named by the American psychologist Robert Abelson. The greebles were created for Isabel Gauthier's dissertation work at Yale, so as to share constraints with faces: they have a small number of parts in a common configuration. Greebles have appeared in psychology textbooks, and in more than 25 scientific articles on perception. They are often used in mental rotation task experiments.
Visual perception is the ability to interpret the surrounding environment through photopic vision, color vision, scotopic vision, and mesopic vision, using light in the visible spectrum reflected by objects in the environment. This is different from visual acuity, which refers to how clearly a person sees. A person can have problems with visual perceptual processing even if they have 20/20 vision.
Perceptual learning is learning better perception skills such as differentiating two musical tones from one another or categorizations of spatial and temporal patterns relevant to real-world expertise. Examples of this may include reading, seeing relations among chess pieces, and knowing whether or not an X-ray image shows a tumor.
Philip Kellman is Distinguished Professor of Psychology and the current Cognitive Area Chair in the Department of Psychology at the University of California, Los Angeles. He is also Adjunct Professor of Surgery in the David Geffen UCLA School of Medicine, and the founder of Insight Learning Technology, Inc, a company that applies perceptual learning, adaptive learning technology, and principles from cognitive science research to improve education and training. His research interests involve perception and visual cognition, specifically visual perception of objects, shape, space, and motion, and perceptual development. He is also an expert in perceptual learning, adaptive learning, and their applications to skill acquisition and educational technology.
Object-based attention refers to the relationship between an ‘object’ representation and a person’s visually stimulated, selective attention, as opposed to a relationship involving either a spatial or a feature representation; although these types of selective attention are not necessarily mutually exclusive. Research into object-based attention suggests that attention improves the quality of the sensory representation of a selected object, and results in the enhanced processing of that object’s features.
Laurent Mottron, born June 13, 1952, in France, is a psychiatrist, researcher, and a professor at Montreal University. He is a specialist in cognitive neuroscience research in autism at the University of Montreal.
Spatial ability or visuo-spatial ability is the capacity to understand, reason, and remember the visual and spatial relations among objects or space.
Farley Norman is a professor of psychological sciences at Western Kentucky University. He is a co-director of the Gustav Fechner Perception Laboratory at Western Kentucky University, along with his wife, Hideko Norman.
In psychology and neuroscience, multiple object tracking (MOT) refers to the ability of humans and other animals to simultaneously monitor multiple objects as they move. It is also the term for certain laboratory techniques used to study this ability.
Lola L. Cuddy is a Canadian psychologist recognized for her contributions to the field of music psychology. She is a professor emerita in the Department of Psychology at Queen's University in Kingston, Ontario.
Michael Herzog is a German neuroscientist and psychophysicist. His interdisciplinary research draws on biology, neurosciences, mathematics, and philosophy with a focus on perception. Herzog is a professor for neuroscience at the School of Life Sciences at EPFL and head of the Laboratory of Psychophysics.
